Browsing by Author "Ameena, M"

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Agro techniques for container grown yardlong bean (Vigna unguiculata var. sesquipedalis (L.) Verdcourt)
(Department of Agronomy, College of Agriculture, Vellayani, 2017) Anjana, S; Ameena, M
Biology and management of goose weed (Sphenoclea zeylanica Gaertner) in wetland rice
(Department of Agronomy, College of Agriculture, Vellayani, 2020) Mallu Sai Sarath Kumar Reddy; Ameena, M
An investigation entitled ‘Biology and management of goose weed (Sphenoclea zeylanica Gaertner) in wetland rice’ was conducted at College of Agriculture, Vellayani during 2018-2020. The major objectives were to study the biology of the weed, its allelopathic effect on crop and also to develop an effective and economic management strategy using herbicides in wet seeded rice. The field experiment was undertaken at IFSRS, Karamana during kharif 2019. Weed biology was studied by observing randomly selected sample plants in weedy check plots starting from the emergence of the weed. The field experiment was laid out in randomized block design with eight treatments and three replications. The weed control treatments included T1: bensulfuron methyl + pretilachlor @ 60+600 g ha-1 at 5 days after sowing(DAS), T2: pyrazosulfuron ethyl @ 25g ha-1 at 5 DAS, T3: bispyribac sodium @ 25 g ha-1 at 15-20 DAS, T4 :penoxsulam + cyhalofop butyl 6% OD at 150 g ha-1 at 20 DAS, T5: metsulfuron methyl + chlorimuron ethyl @ 4g ha-1 at 20 DAS, T6: ethoxysulfuron @ 15 g ha-1 at 20 DAS, T7 : hand weeding at 20 and 40 DAS, T8 : weedy check ( unweeded control) and the treatments T1 to T6 were followed by hand weeding at 35-40 DAS. The lab experiment on allelopathic effect of goose weed on germination and growth of rice seedlings was evaluated with treatments T1: Fresh leaves aqueous extract 10%, T2: Dry leaves aqueous extract 10%, T3: Fresh stem aqueous extract 10%, T4: Dry stem aqueous extract 10%, T5: Fresh inflorescence aqueous extract 10%, T6: Dry inflorescence aqueous extract 10%, T7: Fresh whole plant aqueous extract before flowering 10%, T8: Fresh whole plant aqueous extract after flowering 10%, T9: Distilled water (control). The data on weed biology identified goose weed as an annual. The weed seeds took 3-7 days for germination, 15 days for flowering and 36 days for first spike maturity with an average duration of 69 days in wet seeded rice fields. The weed was observed to propagate by seeds with enormous seed production potential. The average dry matter produced per plant and total dry matter production were to the tune of 26.24 g per plant and 3.75 t ha-1 respectively in the weedy check. The weed was analysed to contain 1.306, 0.087 and 1.695 per cent N, P and K respectively. In the field experiment, Sphenoclea zeylanica was the dominant weed flora during all the growth stages of the crop. Initially, a lower weed density was recorded in T1, but taken over by T4 at 30, 45 and 60 DAS. The weed dry weight was the lowest in T1 at 15 and 30 DAS (0.08 and 6.41 g m-2), whereas at 45 and 60 DAS, T4 recorded the lowest values (1.35 and 4.61 g m-2). T1 registered lesser relative weed density of S. zeylanica up to one month and later by T4. Unweeded plot showed dominance of the weed over other flora with a relative density of 70.33 per cent. Though weed control efficiency was higher in T1 upto 30 DAS (99.28 and 96.22 per cent), T4 recorded higher values during critical stages of crop growth at 45 and 60 DAS (99.54 and 98.85 per cent). T4, T1 and T5 recorded minimum NPK removal and to be precise only one tenth of N removal registered in weedy check in comparison to others due to lower weed dry matter accumulation Among the weed management practices tested, T1 recorded higher plant height at 30, 60 DAS and at harvest. Both T1 and T4 recorded higher yield and yield attributes like number of panicles m-2(320 and 308.3), number of grains panicle-1 (173 and 177), grain yield (5461 and 5355 kg ha-1) and straw yield (7710 and 7646 kg ha-1). Bensulfuron methyl + pretilachlor @ 60+600 g ha-1 at 5 DAS followed by hand weeding at 35-40 DAS turned out to be the most economic weed management practice with a higher B: C ratio of 1.83. This was followed by penoxsulam + cyhalofop butyl 6% OD at 150 g ha-1 at 20 DAS followed by hand weeding at 35-40 DAS with a B: C ratio of 1.77. Higher nutrient uptake by the crop was noticed in bensulfuron methyl + pretilachlor (T1), T4 and T5 due to higher dry matter production. The extent of yield reduction due to presence of weeds in wet seeded rice was estimated to be 57 per cent. The study on allelopathic influence of goose weed revealed strong inhibitory influence for its dry leaves and dry inflorescence on germination percentage (92.67 and 80%) and dry weight (96.98 and 96.12%) of rice seedlings. Shoot length, root length, fresh weight, dry weight and vigour index were also recorded the lowest in T2 and T6. From the results of the study, it could be concluded that Sphenoclea zeylanica could become a serious weed in wetland rice fields being a prolific seed producer with high dry matter production. Application of bensulfuron methyl + pretilachlor @ 60+600 g ha-1at 5 DAS followed by hand weeding at 35-40 DAS was found to be the most effective and economic management strategy. The inference of allelopathic studies indicated that dry leaves and inflorescence of goose weed have strong inhibitory influence affecting germination and growth of rice.
Characterization and management of weedy rice (Oryza sativa f spontanea)
(Department of Agronomy, College of Agriculture, vellayani, 2016) Anjali, K; Ameena, M
Germination ecology and management of chinese sprangletop [Leptochloa chinensis (L.) Nees.] in wet seeded rice
(Department of Agronomy, College of Agriculture Vellayani, 2021) Lekshmi Sekhar; Ameena, M
An investigation entitled ‘Germination ecology and management of Chinese sprangletop [Leptochloa chinensis (L.) Nees.] in wet seeded rice’ was undertaken at the College of Agriculture, Vellayani during 2017-2020. The objectives were to study the habitat, germination ecology and distribution of Leptochloa chinensis in major rice growing tracts of Kerala; to test the efficacy of tank mix combinations of herbicides for the management of the weed; to test the sensitivity of the weed to herbicide combinations and to assess the mode of action of the herbicide combinations. The phytosociological survey was conducted to document the habitat, composition and distribution of L. chinensis in different rice tracts of Kerala viz., Palakkad, Kole and Kuttanad after selecting three severely infested padasekharams in each tract during 2018 and 2019. L. chinensis was found to occur in all the major rice growing tracts of Kerala and registered summed dominance ratio of 13.05, 12.40 and 17.49, respectively in Kuttanad, Kole and Palakkad (Kharif). Appraisal of weed vegetation analysis indices displayed the highest weed species richness (17) and Simpson’s diversity index in Kole and the lowest Shannon Wiener diversity index (2.09) in Palakkad. L. chinensis was the dominant weed in all these tracts with an abundance of 17.33, 17.0 and 16.36, respectively and the weed inhabited both upland and lowland situations, either in crop lands, field bunds, stream banks or waterways. Profuse growth of the weed was observed along the inner bunds separating individual fields. The weed was a prolific seed producer with seed production potential ranging from 7400-33,941 seeds per plant across the surveyed locations. Germination ecology experiments encompassed studies on weed phenology and germination of Chinese sprangletop. L. chinensis is an erect or creeping, annual or perennial grass that can grow upto a height of 120-150 cm, propagates both by seed and slips with very minute seeds (thousand seed weight of 0.10-0.18 g). The weed was noticed to develop through five phenological stages, viz., emergence, tillering, heading, flowering and maturity with an average duration of 10.6, 41.5, 73.5, 78.5 and 95 days, respectively. Investigations on germination ecology revealed that light was not an absolute requirement for germination of seeds of L. chinensis, but stimulated germination by 23 per cent. When exposed to alternating temperatures in light/dark, seeds germinated at 15°C to 35°C. The highest germination occurred at 25/15°C (87.2%), while at 35/25°C it was only 70.31 per cent. Germination of L. chinensis was significantly influenced by moisture regime; with zero germination under continuous flooding or with thin layer of water (3 cm) and 70 per cent germination on irrigating at alternate days. Seedling emergence was also significantly affected by seed burial depth. Seedling emergence was high (85%) for seeds placed on the soil surface, while no emergence was observed at burial depths of 2 cm or beyond. Slips placed at the surface recorded 100 per cent sprouting and the time taken for 50 per cent emergence increased with increase in burial depth. The seeds germinated upto nine months after harvest with the germination declining over time. The field experiments on management of L. chinensis were conducted during 2018 and 2019 Kharif at Integrated Farming System Research Station, Karamana. The experiment was laid out in randomized block design with 10 treatments and three replications. The treatments included T1: cyhalofop butyl @ 0.08 kg ha-1 , T2: penoxsulam + cyhalofop butyl (6% OD) @ 0.15 kg ha-1 , T3: cyhalofop butyl + carfentrazone ethyl @ 0.08 + 0.02 kg ha-1 , T4: bispyribac sodium @ 0.025 kg ha-1 , T5: bispyribac sodium + cyhalofop butyl @ 0.025 + 0.08 kg ha-1 , T6: bispyribac sodium + fenoxaprop-p-ethyl @ 0.025 + 0.06 kg ha-1 , T7: fenoxaprop-p-ethyl @ 0.06 kg ha-1 , T8: stale seedbed followed by (fb) glyphosate + oxyfluorfen @ 0.8 + 0.15 kg ha-1 at 15-20 days after land preparation fb cyhalofop butyl + carfentrazone ethyl @ 0.08 + 0.02 kg ha-1 , T9: unweeded control and T10: hand weeding twice at 20 and 45 days after sowing (DAS). The weed management practices had significant influence on L. chinensis count, dry matter production, control efficiency and nutrient removal at different stages of observation. Count of L. chinensis was zero in T6, T7, T8 and T10 at 15 days after treatment application (DATA) during both the years. The lowest count and dry matter production and the highest pooled control efficiency of L. chinensis (97.55 and 96.78 per cent, respectively at 30 and 45 DATA) was registered in T7. It was statistically on par with all other treatments except T4 and T9. Bispyribac sodium was not effective in controlling L. chinensis and resulted in lower control efficiency of 52.63, 38.68 and 42.43 per cent, respectively at 15, 30 and 45 DATA. However, its combination with fenoxaprop-p-ethyl (T6) or cyhalofop butyl (T5) resulted in higher control efficiency of L. chinensis at all stages of observation and recorded 100, 96.06 and 95.96 and 97.23, 92.37 and 94.55 per cent, respectively at 15, 30 and 45 DATA. Among the herbicide treatments, T6 registered the least total weed dry matter production at all stages and resulted in the highest pooled weed control efficiency of 98.20 and 89.70 per cent which was on par with T2 (96.61 and 83.86%) and T5 (95.40 and 84.81%) respectively at 30 and 45 DATA. The highest pooled grain yield (5.03 t ha-1 ) also was registered in T6 which was on par with T2 and T5 with 4.79 and 4.76 t ha-1 . Pooled data revealed that season long weed competition in wet seeded rice (WSR) with L. chinensis as a major weed caused a yield reduction of 59.95 per cent. Compared to the unweeded control, herbicidal treatments enhanced grain yield by 23.89-58.84 per cent, whereas herbicide combinations increased grain yield by 56-59 per cent in WSR. Pooled mean of the economics of cultivation registered maximum net returns per hectare (₹ 63,657 ha-1 ) and B:C ratio (1.81) in T6 followed by T2 (₹ 56,995 ha-1 and 1.73) and T5 (₹ 56,044 ha-1 and 1.72). The sensitivity of L. chinensis to herbicide combinations was tested at the field recommended dose and its lower doses using whole plant bioassay technique after identifying best combinations viz., bispyribac sodium + fenoxaprop-p-ethyl @ 0.025 + 0.06 kg ha-1 , bispyribac sodium + cyhalofop butyl @ 0.025 + 0.08 kg ha-1 , penoxsulam + cyhalofop butyl @ 0.15 kg ha-1 and cyhalofop butyl + carfentrazone ethyl @ 0.08 + 0.02 kg ha-1 . The experiment was laid out in completely randomized design (CRD) with eight treatments and three replications. Lower dose of bispyribac sodium + fenoxaprop-p-ethyl @ 0.020 + 0.04 kg ha-1 recorded the least survival (0%) of L. chinensis whereas, bispyribac sodium + cyhalofop butyl @ 0.020 + 0.06 kg ha-1 , cyhalofop butyl + carfentrazone ethyl @ 0.06 + 0.01 kg ha-1 and penoxsulam + cyhalofop butyl @ 0.10 kg ha-1 registered 26.66, 30.0 and 86.66 per cent survival, respectively. The experiment on mode of action of tank mix herbicide combination was laid out in CRD with four treatments and five replications. The treatments included T1: ALS inhibitor alone (bispyribac sodium @ 0.025 kg ha-1 ), T2: ACCase inhibitor alone (fenoxaprop-p-ethyl @ 0.06 kg ha-1 ), T3: ALS + ACCase inhibitor (bispyribac sodium @ 0.025 kg ha-1 + fenoxaprop-p-ethyl @ 0.06 kg ha-1 ) and T4: Control. Treatment T3 recorded lower amino acid content (0.1775 mg mL-1 ) than T1 (0.2904 mg mL-1 ) confirming that the combined application of an ALS + ACCase inhibitor could provide better control of L. chinensis compared to sole application of ALS inhibitor. The experiment on assessing the differential response of L. chinensis and Echinochloa colona to the broad-spectrum herbicide bispyribac sodium, revealed that amino acid content of L. chinensis was not influenced by the increasing concentration of bispyribac sodium. High content of amino acid was registered in L. chinensis (0.2904 and 0.3234 mg mL-1 ) compared to E. colona irrespective of the concentration of bispyribac sodium. However, in E. colona, the amino acid content (0.1520 and 0.0627 mg mL-1 ) was found to decrease with increasing concentration of bispyribac sodium. The present study identified L. chinensis as a major weed in all the major rice growing tracts of Kerala indicating its invasive potential under diverse environmental conditions owing to its prolific seed production, sprouting from weed slips on soil surface, extended period of seed viability and different mode of propagation. The results revealed that early and continuous flooding, deep tillage for burial of seeds and slips into the soil beyond 5 cm could suppress its emergence. The study identified fenoxaprop-p-ethyl @ 0.06 kg ha-1 as the most effective herbicide against L. chinensis to be sprayed at 15-18 DAS in WSR. In areas where L. chinensis is a dominant weed in the WSR, tank mix application of bispyribac sodium @ 0.025 kg ha-1 + fenoxapropp-ethyl @ 0.06 kg ha-1 at 15-18 DAS could be recommended for broad spectrum weed management. Whole plant bioassay of the above combination proved effective at its still lower dose and the differential response of L. chinensis to bispyribac sodium indicated herbicide combinations for managing the complex spectrum of weeds in wet seeded rice.
Herbicide based weed management for semi dry rice (Oryza sativa L.)
(Department of Agronomy, College of Agriculture, Vellayani, 2015) Arya, S R; Ameena, M
An investigation entitled “Herbicide based weed management for semi dry rice (Oryza sativa L.)” was conducted during the period May to September 2014 at farmer’s field in Nemom block, Thiruvanthapuram. The main objectives of the study were to evaluate the weed control efficiency of new generation herbicides in semi dry rice, to assess their selectivity and influence on growth and yield, to work out the economics and to develop a weed management strategy for semi dry rice.The field experiment comprised of eleven treatments replicated thrice (Variety: Uma) was laid out in randomised block design. The treatments were T1: bensulfuronmethyl + pretilachlor @ 60 + 600 g a.i. ha-1 (pre - emergence), T2: T1 + hand weeding at 40 DAS, T3: T1 + azimsulfuron @ 30 g a.i. ha-1 (post emergence), T4: pyrazosulfuron ethyl @ 25 g a.i. ha-1 (pre - emergence),T5: T4 + hand weeding at 40 DAS, T6 : T4 + azimsulfuron @ 30 g a.i. ha-1 (post emergence), T7 : oxyfluorfen @ 0.15 kg a.i. ha-1 (pre - emergence), T8 : T7 + hand weeding at 40 DAS, T9 : T7 + azimsulfuron @ 30 g a.i. ha-1 (post emergence) and two controls: T10: hand weeding at 20 and 40 DAS and T11: weedy check. Result of the study revealed substantial reduction in weed population and biomass in all the herbicide treated plots compared to weedy check. Weed composition of the experimental field indicated the dominance of broad leaved weeds followed by sedges and grasses with considerable variation in weed flora during dry and flooded condition.Hand weeding at 20 and 40 DAS (T10) recorded lowest weed density, weed dry weight and highest weed control efficiency. Absolute frequency (Af) for all weed species throughout the crop growth stages was also lower under hand weeding while higher values of importance value (IV) and summed dominance ratio (SDR) for sedges and broad leaved weeds were recorded in weedy check (T11). Pre-emergent herbicide application followed by either hand weeding at 40 DAS (T2 and T5) or application of post emergent herbicides (T3 and T6) recorded higher weed control efficiency and lower nutrient removal in comparison with hand weeding twice (20 and 40 DAS). None of the herbicides produced any phytotoxic symptoms on rice plant. However, crop density and growth was lower at the initial stages in oxyfluorfen treated plots. This indicated that bensulfuron methyl + pretilachlor and pyrazosulfuron can be treated as safe pre-emergent herbicides for dry sown (semi dry) system of rice cultivation. Result of the study also indicated the safety of the herbicides on microbial activity as evidenced by the increase in soil dehydrogenase activity in herbicides applied plots.The yield attributes of rice viz., number of productive tillers m-2 and filled grains panicle-1 were significantly influenced by the weed management practices T2, T3, T5, T6 and T10. Grain yield (4817.67 kg ha-1) and straw yield (7969.33 kg ha-1) were significantly higher in T2 (bensulfuronmethyl + pretilachlor @ 60 + 600 g a.i. ha-1 + hand weeding at 40 DAS) and remained on par with T3, T5, T6 and T10. Yield loss due to weeds was found to be 52.22 per cent. The most economically viable weed management practice was T6 (bensulfuronmethyl + pretilachlor fb azimsulfuron) with a B: C ratio of 1.76 which was on par with T3 (1.75). Grain yield, net income and B: C ratio were significantly lower in weedy check.It can be concluded that the most effective weed management practice for semi dry rice is pre-emergence application of either bensulfuron methyl + pretilachlor @ 60 + 600 g a.i. ha-1 or pyrazosulfuron ethyl @ 25 g a.i. ha-1 on the next day of sowing followed by post emergence application of azimsulfuron @ 30 g a.i. ha-1 at 25 DAS.
Integrated management of purple nutsedge
(Department of Agronomy, College of Horticulture, Vellayani, 2003) Ameena, M; Geetha Kumari, V L
An investigation entitled "Integrated management of purple nutsedge (Cyperus rotundus L.)" was conducted during 1999-2002 at College of Agriculture, Vellayani, Thiruvananthapuram. It comprised of one pot study, two field experiments and three laboratory experiments. Pot experiment was conducted to study the biology of purple nutsedge under various seasons and stage of tuberisation. Field experiments were conducted to evolve an integrated management strategy for purple nutsedge control in cropped area and a long-term control strategy in non- cropped area. Laboratory experiments were conducted to assess the allelopathic influence of purple nutsedge root exudates on early growth of crop seeds and nutsedge extracts on weed seeds. An attempt has been made to identify the allelochemicals present in tubers of nutsedge by employing HPLC (High Performance Liquid Chromatography) technique. In pot study, the growth and development of purple nutsedge was observed for a period of one year. Results of the study indicated that chain tuber took more time for sprouting compared to shoot tubers or bulb. The time required to sprout varied with seasons in the case of chain tuber and August and March planted tubers took lesser time for sprouting. March and May planting tecorded more tuber production compared to August and November planting. August planted tubers recorded very early tuberisation and November and May planted tubers took more or less double the time for tuberisation compared to August planted tubers. Field studies in cropped area indicated that the growth characters of okra were significantly influenced by the weed management practices. Flowering was early by about 7-10 days in mulched plots under both stale seed bed and soil exposure treatments compared to weedy check plots. Stale seed bed coupled with mulching registered maximum leaf area index during both the years. All the weed control treatments except where cowpea was raised as smother crop resulted in significantly more fruits per plant and fruit yield per hectare. Maximum productivity of 5.24 t ha" was realised by stale seed bed with eucalyptus mulched plots which was 171.5 and 11 per cent more than weedy check and weed free plots respectively. The treatments had no significant influence on quality attributes of okra like vitamin C, keeping 'quality, protein and fibre content of fruits. Regarding soil fertility status, minimum depletion of nutrients occurred in completely weed free and mulched plots. Stale seed bed with polythene mulching or pre and post emergent glyphosate application were identified as the best nutsedge control measure in cropped area. Post emergent glyphosate application after stale seed bed has found to show spectacular inhibitory effect on nutsedge multiplication and spread and this treatment recorded the highest percentage reduction values for nutsedge control. Lowest rate of regeneration was recorded by this treatment with lower viability of tubers. The most economical treatment was stale seed bed with glyphosate application integrated with eucalyptus mulching and it recorded the highest net returns (Rs.18,2701-) and B:C ratio (2.01). In non-cropped area. results of two seasons study indicated that the effective stage for glyphosate spraying was identified as before tuber initiation. The degree of inhibition exerted by glyphosate on regeneration of nutsedge tubers was higher thanthat of 2.4-0. Among the summer season treatments stale seed bed with irrigation followed by glyphosate application was the best in achieving higher level of control. In allelopathic studies. nutsedge root exudates collected at sprouting stage inhibited the germination and growth of all the crop seeds tested vi : .. rice. co wpea. sesamum. okra and brinjal. Also the nutsedge extracts collected at different stages inhibited the growth and development of Gomphrena de cumbe nse and Syne drell a nodij7ora. The allelochemicals present in tubers of purple nutsedge was identified by High Performance Liquid Chromatography (HPLC) and it indicated the presence of p-hydroxy benzoic acid, p-coumaric acid, m- coumaric acid, vanillic acid and gentisic acid.
Integrated management of purple nutsedge (Cyperus rotundus L.) in grain legumes
(Department of Agronomy, College of Agriculture,Vellayani, 2025-06-20) Mena Sai Rajeswari Kalyani; Ameena, M
The study entitled ‘Integrated management of purple nutsedge (Cyperus rotundus L.) in grain legumes’ was conducted at the College of Agriculture, Vellayani, Thiruvananthapuram, Kerala, during 2020-2025. The objectives of the study were to standardize land preparation methods to deplete the tuber reserves of nutsedge, formulate an integrated management strategy for Cyperus rotundus in grain cowpea, assess the residual effect of the herbicides on successive crop, and evaluate the in vitro sensitivity of beneficial organisms to these herbicides. The investigation comprised of five experiments. The first experiment was conducted was conducted at Instructional Farm, College of Agriculture, Vellayani to evaluate the efficacy of land preparation methods to exhaust tuber reserve and nutsedge regeneration. The experiment was laid out in randomized complete block design (RCBD) with eight treatments replicated thrice. The treatments were: T1 [stale seed bed method (SSB) with halosulfuron methyl at 60 g ha-1], T2 [SSB with halosulfuron methyl at 67.5 g ha-1], T3 [SSB with halosulfuron methyl at 75 g ha-1], T4 [SSB with chlorimuron ethyl at 9 g ha-1], T5 [SSB with chlorimuron ethyl at 12 g ha-1], T6 [SSB with glyphosate at 1.5 kg ha-1], T7 [SSB with mechanical destruction] and T8 [SSB alone]. The herbicides were applied when the nutsedge plants were at three to four leaf stage. Results revealed that T6 resulted in lower final population, shoot dry weight, tuber dry weight and tuber viability of nutsedge at 6 weeks after spraying of herbicide (WASP) and comparable with T3 and T2. The treatments, T6, T3 and T2 resulted in higher weed control efficiency (88.52, 82.28 and 82.27 %, respectively) and lower regeneration count at 6 WASP (11.11, 13.33 and 15.56 m-2). The study confirmed that halosulfuron methyl at 67.5 g ha-1 was equally effective as glyphosate at 1.5 kg ha-1 in depleting the tuber reserves and regeneration count of C. rotundus under SSB and hence, this treatment was selected as the most effective land preparation method for raising grain cowpea. The second experiment ‘Integrated management of purple nutsedge’ was conducted in the locations having severe nutsedge infestation at Instructional Farm, College of Agriculture, Vellayani during first (kharif) and second crop (rabi) seasons of 2022-23. The experiment was laid out in RCBD with nine treatments replicated thrice. The treatments comprised of T1 (pre-emergence diclosulam at 12.5g ha-1), T2 (post directed application of chlorimuron ethyl at 9 g ha-1 at 20 DAS), T3 (post emergence haloxyfop R methyl at 100 g ha-1 at 20 DAS), T4 (T1 followed by (fb) wheel hoe weeding (WH) at 25 DAS), T5 (T2 fb WH at 40 DAS), T6 (T3 fb WH at 40 DAS), T7 (pre-emergence pretilachlor at 0.75 kg ha-1), T8 (hand weeding twice at 20 and 40 DAS) and T9 (weedy check). The grain cowpea variety DC-15 was raised as per KAU POP recommendations. The growth parameters of grain cowpea were significantly influenced by the weed management practices. The treatment T4 resulted in taller plants, higher branches per plant, green leaves per plant, leaf area index and dry matter production per plant at harvest and was comparable with T8 and T1 during both the seasons. The yield attributes viz., number of pods per plant, pod weight per plant, seed yield and haulm yield per plant were found to be higher in T4 during both the seasons. Pooled analysis over both seasons revealed that the highest seed yield was recorded in T4 (1717 kg ha-1) while the lowest in T9 (871 kg ha-1). The yield reduction due to weeds in cowpea was estimated to be 46.66 per cent during kharif and 50.56 per cent during rabi. The treatment T4 resulted in lower total weed population and dry weight resulting in higher weed control efficiency at 15 and 30 DAS during both kharif (90.96 and 84.50 %, respectively) and rabi seasons (78.84 and 82.67 %, respectively). Lower regeneration counts of C. rotundus at 45 DAS was noted in T4 (13.33 and 11.10 m-2) during both seasons, respectively. The N, P and K removal by weeds was found to be lower at 15 and 30 DAS in T4 during both seasons. Further, at just before spraying, T6 showed higher microbial and enzyme activity, while T8 noted the highest microbial and enzyme activity at 15 and 30 days after spraying, across both the seasons. Pre emergence diclosulam (12.5 g ha-1) fb WH at 25 DAS turned out to be the most economic nutsedge management strategy in cowpea with higher net income (₹ 41,894 and ₹ 19,081 ha-1) and B: C ratio (1.69 and 1.32) during kharif and rabi seasons, respectively and was comparable with T1. The third experiment ‘Screening of indicator plants’ was conducted in a net house with two test crops (finger millet and cucumber) and three herbicides (diclosulam, halosulfuron methyl and haloxyfop R methyl) to identify the most sensitive indicator plant for each herbicide. The experiment was laid out in completely randomised design (CRD) with eight treatments replicated thrice. Treatments comprised of different concentrations of the test herbicides (ppm) viz., T1 (0.01), T2 (0.05), T3 (0.1), T4 (0.5), T5 (1.0), T6 (10), T7 (100) and T8 (control). Results revealed that all the three tested herbicides had a significant impact on the growth of both the crops tested. As herbicide concentration increased, there was a corresponding decline in shoot length, root length, shoot and root dry weights of both test crops. Finger millet exhibited greater sensitivity to diclosulam and halosulfuron methyl than cucumber, with the highest R² values recorded for all parameters using cubic polynomial regression equations and hence selected as the successive crop for assessing residual herbicide effects. The fourth experiment ‘Assessing the residual effect of herbicides on succeeding crop’ was carried out after the harvest of cowpea using the finger millet variety VR-847. Hundred per cent seedling emergence without significant grain yield reduction was observed indicating no residual impact of the herbicides on successive crop. The fifth experiment ‘in vitro sensitivity of beneficial organisms’ was conducted to assess in vitro sensitivity of Trichodermaasperellum and Rhizobium sp. (RH-15) to three herbicides (diclosulam, halosulfuron methyl and haloxyfop R methyl). The experiment was laid out in CRD with eight treatments replicated thrice. The treatments comprised of different concentrations (ppm) of diclosulam (T1-20, T2- 25, T3- 30, T4- 35, T5- 40, T6- 45, T7- 50 and T8-control); halosulfuron methyl (T1-100, T2 120, T3- 140, T4- 160, T5- 180, T6- 200, T7- 220 and T8-control) and haloxyfop R methyl (T1-180, T2-200, T3- 220, T4- 240, T5- 260, T6- 280, T7- 300 and T8-control). Results revealed that diclosulam and haloxyfop R methyl had no significant effect on the radial growth of Trichodermaasperellum, with all concentrations showing uniform colony diameter of 9 cm and zero inhibition. In contrast, halosulfuron methyl significantly inhibited T. asperellum growth, ranging from 38.55 to 76.67 per cent. Further, Rhizobium sp. showed no zone of inhibition for any of the three herbicides, indicating no adverse effect on its growth. The study identified stale seedbed with halosulfuron methyl (67.5 g ha-1) followed by pre-emergence diclosulam (12.5 g ha-1) along with wheel hoe weeding at 25 DAS as the most effective and economical integrated management strategy for purple nutsedge in grain cowpea. The tested herbicides (diclosulam, halosulfuron methyl, and haloxyfop R methyl) had no adverse effects on soil health, enzyme activity, or residual impact and were compatible with Rhizobium sp. However, Trichodermaasperellum showed sensitivity to halosulfuron methyl.
Integrated weed management in blackgram [Vigna mungo (L.) Hepper] with pre-mix herbicides.
(Department of Agronomy, College of Agriculture, Vellayani, 2025-05-05) Ameena, M
An investigation entitled ‘Integrated weed management in blackgram [Vigna mungo (L.) Hepper] with pre-mix herbicides’ was conducted at College of Agriculture, Vellayani during 2022-2024. The major objective was to formulate an integrated weed management strategy using pre-mix herbicides for black gram intercropped in coconut garden. The field experiment was conducted at the Instructional Farm, Vellayani during the summer season from February to April 2024 in a coconut garden with palms above 40 years of age. The experiment was laid out in randomized block design with nine treatments replicated thrice. The weed management practices tested were: T1- pre emergence (PE) pendimethalin + imazethapyr (premix 1) 800 g ha-1; T2 - T1 followed by (fb) hand weeding (HW) at 30 days after sowing (DAS); T3- post emergence (PoE) propaquizafop + imazethapyr (premix 2) 125 g ha-1; T4- T3 fb HW at 40 DAS; T5- PE pendimethalin 1kg ha-1 fb HW at 30 DAS; T6- PE pendimethalin 1kg ha-1fb PoE imazethapyr 50g ha-1; T7- PE pendimethalin 1kg ha-1 fb PoE propaquizafop 100g ha- 1; T8- HW at 15 and 30 DAS; T9- weedy check. The blackgram variety DBGV-5 treated with Bradyrhizobium inoculant BMBS 47 was dibbled in the interspaces of coconut and managed as per the KAU Package of Practices. Pre emergence herbicide was applied on the next day of sowing and post emergence applied at 15 DAS. Symptoms of phytotoxicity were observed in crop as mild stunting in plots sprayed with premix combination, pendimethalin + imazethapyr which persisted upto 10 days after herbicide application. The results of the study revealed that weed management practices had no significant influence on the growth attributes of blackgram. However, the yield and yield attributes were significantly influenced by the weed management practices. Higher pods per plant was recorded in T4 (36.00) and was comparable with T7 (35.83) while weedy check recorded the lowest number of pods (14.24). Hundred seed weight was recorded higher in T2 (5.33 g) and was on par with T4 (5.17 g) and T1 (5.13 g). The highest seed yield per plant was recorded in T4 (9.60 g) followed by T7 (9.23g), T6 (8.3g) and T5 (8.23g). Post emergence application of premix 2 fb HW at 40 DAS resulted in higher seed yield per ha (1793 kg) and was comparable with T7 (1731 kg). Higher haulm yield per ha was recorded in T5 (3658 kg) and was comparable with T4 (3616 kg), T6 (3581 kg) and T7 (3485 kg). The study observed that absence of weeding led to the highest yield reduction in blackgram, with a weed index of 54.44 per cent while yield reduction was lower in T4 (2.45%) and on par with T7 (5.35%). The predominant weed flora in the experimental field was grasses. However, more diversity was observed in the flora of broad leaf weeds. Pre emergence application of premix 1 fb HW at 30 DAS resulted in significantly lower weed density and weed dry weight and higher weed control efficiency at all stages of observation and was comparable with T7, T4 and T6. At 30 and 45 DAS, T1, T2, T5, T6 and T7 resulted in lower relative biomass of grasses that was comparable with T4 and the highest relative biomass of grasses was recorded in weedy check (85.92 %). Treatments involving both pre- and post-emergence herbicide applications (T7 and T6) resulted in higher dehydrogenase enzyme activity at 30 DAS, while their combination with hand weeding (T4, T5) showed increased activity at 45 DAS. Weed management practices significantly influenced nutrient uptake, with T7 and T1 exhibiting higher N, P and K uptake. The integration of premix herbicides with hand weeding and use of pre and post-emergence herbicides, significantly reduced N, P, and K removal by weeds throughout the growth period. The BC ratio varied significantly among the weed management practices with the highest in T4 (1.95), followed by T7 (1.94), with the lowest ratios in hand weeding twice (1.05) and weedy check (0.82). Weed management practices significantly influenced the population of Bradyrhizobium, fungi and actinomycetes in rhizospheric soil at 30 DAS with T2 showing higher count and on par with T1. However, no significant differences were noted in the population of phosphorus solubilising bacteria across all time points. The in vitro sensitivity test of Bradyrhizobium to premix 1 and 2 at concentrations of 800 to 2000 ppm and 175 to 325 ppm respectively showed positive growth with no inhibition zones around the sterile disc containing herbicide mixture placed on a lawn of Bradyrhizobium in the medium. The study identified application of propaquizafop + imazethapyr 125 g ha-1 at 15 DAS fb HW at 40 DAS; and application of pendimethalin 1kg ha-1 on the next day of sowing fb propaquizafop 100g ha-1 at 15 DAS as the most effective weed management strategies in terms of yield, weed control efficiency and gross return in blackgram. Considering economics, application of propaquizafop + imazethapyr at 15 DAS fb HW at 40 DAS could be adjudged as the most effective integrated weed management strategy for achieving higher seed yield in blackgram intercropped in coconut garden.
Integrating weed management with nano nitrogen in okra(Abelmoschus esculentus(L.) moench)
(Department of agronomy, college of agriculture, Vellayani, 2023-09-21) Navaneetha, C; Ameena, M
Integrating weed management with nano nitrogen in okra(Abelmoschus esculentus(L.) moench)
(Department of agronomy, collegeof agriculture ,Vellayani, 2023-09-21) Navaneetha, C; Ameena, M
Investigation on allelopathic influence and control of purple nuts edge
(Department of Agronomy, College of Agriculture, Vellayani, 1999) Ameena, M; Sansamma George
Lab and field experiments were conducted at the Instructional farm, College of Agriculture, Vellayani to study the allelopathic influence of Purple nutsedge (Cyperus rotund us L) on important field crops; to investigate the effectiveness of systemic herbicides for control of nutsedge and also to assess the effect of chemical weed control on growth and yield of subsequent field crops. In Ex. no. I, allelopathic influence of purple nutsedge on important field crops like rice, ragi, cowpea, green gram, bitter gourd and bhindi were studied. The treatments comprised of aqueous extracts and blended extracts of fresh and dry plant parts of nutsedge. The results revealed that aqueous extracts of nutsedge inhibited germination of rice, ragi, bitter gourd and bhindi while it had some stimulatory effect on germination of cowpea and green gram. The early growth characters of the field crops were found suppressed by the aqueous extract treatment while the blended extract showed no effect. In general, the dry plant parts showed greater effect than the fresh material. Under Ex.no.Il, field studies were made to investigate the effectiveness of systemic herbicides viz. Glyphosate and 2,4-D for control of nutsedge. The treatments included different doses of the herbicides with and without adjuvants and Glyphosate combined with sublethal dose of 2,4-D. The results revealed that lowest dose of the herbicides were sufficient for complete kill of the purple nutsedge plants in the experimental area and there was no regrowth upto 6 weeks. There was significant reduction in viability of tubers collected one month after herbicide application, but the tubers tested 45 days after spraying showed an increase in germinability over the record on 30th day. Tubers from treatments involving Glyphosate with sublethal dose of 2,4-D recorded the lowest sprouting percentage indicating the possibility for weed control for a longer period. In Ex. no. In, the persistence of the herbicides in soil were monitored and it was observed that early growth of cucumber sown on the same day of herbicide application was affected while that sown on soils collected 10 days after spraying recorded growth characters comparable to that of control. From Ex.no.IV, it could be inferred that chemical weed control did not show any deleterious effect on growth and yield characteristics of ragi and cucumber sown 15 days after the treatments. Application of 2,4-D for nutsedge control was found superior to other treatments in terms of net income and B:C ratio and the lower unit cost of the chemical was precisely the reason for its superiority.
Management of rock bulrush (schoenoplectus juncoides (roxb.) palla) in wet seeded rice
(Department of Agronomy, College of Agriculture, Vellayani, 2018) Fathima Umkhulzum, S; Ameena, M
An investigation entitled "Management of rock bulrush (Schoenoplectus juncoides (Roxb.)Palla) in wet seeded rice" was conducted at College of Agriculture, Vellayani during 2016 to 2018. The major objective were to study the biology of the weed rock bulrush (Schoenoplectus juncoides (Roxb.) Palla) and to develop an effecetive and economic method for its management in wet seeded rice. Field experiment was undertaken in farmer's field at Nemom block, Thiruvannathapuram during rabi season (November 2017 to march 2018). Weed biology was studied by observing sample plants in weedy check plots starting from the emergence of the weed. The experiment was laid out in Randomized Block Design with 8 treatments replicated thrice. The experiment was laid out in Randomized Block Design with 8 treatment replicated thrice. The weed management practices tested were:T1-bensulfuron methyl+ pretilachlor @ 60+600 g ha-1 at 4-7 days after sowing (DAS) followed by (fb) hand weeding (HW) at 35-40 DAS; T2-penoxsulam @ 22.5 g ha-1 at 15 DAS fb HW at 35-40 DAS;T3 - ethoxysulfuron @ 15 g ha-1 at 15 DAS fb HW at 35-40DAS;T4-carfentrazone-ethyl @20 g ha-1 at 15 DAS fb HW at 35-40 DAS;T5-metsulfuron methyl +cholimuron ethyl @ 4 g ha-1 at 20 DAS fb HW at 35-40 DAS;T7- HWtwice at 20 and 40 DAS and T8-weedy check. Pre-germinated seeds of var. Sreyas (M) 22) were broadcasted in the puddled soil following all cultural practices as per KAU PoP (KAU, 2011) except weed management. Study on weed biology revealed that the weed behaved as annual/perennial depending on field situation, with an average duration of 106 days in continuously cultivated fields. Phenology of rock bulrush revealed that the weed took 5 days for seed germination, 22 days for flowering, 33 days for spike maturity and 68 days for seed maturity after wet seedign of rice. The weed echibited a lodging behaviour after spike maturity . Seeds were observed to be the main propagule however, vegetative buds and rhizomes also helped in propagation. Lodging after spike maturity and spiny apex of seeds were found to facilitate seed dispersal. The weed was observed to be a prolific seed producer (862 seeds plant-1) with a biomass production of 0.96 t ha-1 as worked out from weedy check plots. The nutrient content of the weed was analyzed to be 0.90,0.33 and 1.14 per cent NPK respectively. Among th weed management practices tested, ethoxysullfuron @ 15 g ha-1 at 15 DAS fb HW at 35-40 DAS (T3) wa significabtly superior to all other treatments with respect to number of productive tillers m-2 (382), number of grains panicle-1 (134.27), filled grains panicle-1 (115.85), grain yield (5750 kg ha-1 and straw yield (9955 kg ha-1). Grain yield recorded in penoxsulam @ 22.5 hg ha-1 at 15 DAS fb HW at 35-40 DAS (5500.76 kg ha-1) was on par with T3. These treatments also recorded higher B: C ratios of 2.26 and 2.11 respectively. At 45 and 60 DAS, lower weed density (2.09 and 3.15 respectively) and weed dry weight (0.13 and 1.83 g m-2 ewspectively) were recorded for enthoxysulfuron @ 15 g ha-1 at DAS fb HW at 35-40 DAS. Higher weed control efficienceis of 99.82 and 98.07 per cent were obtained in plots treated wih ethoxysulfuron @ 15 g ha-1 at 15 DAS fb HW at 35-40 DAS during critical stages of crop weed competition (45 and 60 DAS). Penoxsulam @ 22.5 g ha-1 at 15 DAS fb HW at 35-40 DAS was on par with T3 at 45 and 60 DAS recording weed control efficeincies of 99.07 and97.90 per cent respectively. Uncontrolled weed growth in wet seeded broadcasted rice could cause a yield reduction of 52.18 percent. Higher crop uptake (kg ha-1 ) of N (219.01), P (39.32) ane K (228.55) were recorded in T3 and it was statistically on par with T2, T6 and T7. The weed removal of N, P and K (8.61, 3.13 and 10.95 kg ha -1 respeectively) were aslo lower with ethoxysulfuron @ 15 g ha-1 15 DAS fb HW at 35-40 DAS. Schoenoplectus juncoides was observed to be an emerging sedge weed in the cultivated wet lands with round upright culms having annual or perennial nature, reproducing by seeds or rhizhomes with a biomass production of 0.96 t ha -1, if uncontrolled. The weed could be effectively controlled by ethoxysulfuron @ 15g ha-1 or penoxsulam @ 22.5 g ha-1 both at 15 DAS fb HW at 35-40 DAS. Considering the economics, ethoxysulfuron @ 15 g ha -1 at 15 DAS followed by hand weeding at 35-40 DAS could be adjudged as the most effective strategy for the management of Schoenoplectus juincoides (Roxb.) Palla in wet seeded rice.
Mitigating water stress in summer rice using beneficial root endophytic fungus Piriformospora indica
(Department of Agronomy, College of Agriculture, Vellayani, 2021) Koya Madhuri, Mani; Ameena, M
The study entitled ‘Mitigating water stress in summer rice using beneficial root endophytic fungus Piriformospora indica’ was undertaken at College of Agriculture, Vellayani during 2019 - 2021. The objective of the study was to assess the performance of P. indica colonized rice under different levels of moisture stress during summer. The field experiment was laid out in randomized block design with 2 x 3 x 2 treatments, replicated thrice in the low land paddy fields during February to May 2021, using variety Prathyasa. The treatments included colonizing with P. indica [p1- P. indica colonized rice and p2- non-colonized rice(control)], three irrigation intervals[i1- 30 mm CPE (cumulative pan evaporation), i2- 35 mm CPE and i3- 40mm CPE] and two irrigation depths(d1- to a depth of 1.5 cm and d2- to a depth of 3 cm). P. indica colonized/ non-colonized rice seedlings raised in trays were transplanted at 14 days after sowing at 15 cm x 10 cm and uniformly irrigated till 10 days after transplanting (DAT). The crop was raised as per the KAU package of practices recommendation for short duration rice (KAU, 2016). The results of the study revealed that colonization and irrigation to 3 cm depth improved the growth and growth attributes viz., plant height, tiller number m-2 , leaf area index and dry matter production of summer rice. Colonization with P.indica significantly influenced the number of tillers m-2 with 10.64, 16 and 15.69 per cent increase in tiller production at 30, 45 and 60 DAT respectively, compared to non-colonized plants. Colonized plants irrigated at 30 mm CPE to a depth of 3 cm evinced the maximum leaf area index (4.54) at 60 DAT and dry matter production (4559.26 kg ha-1 ) at harvest. Yield attributes and yield of rice were significantly affected by P. indica colonization, irrigation interval and depth of irrigation. Superior number of productive tillers m-2 (222.84), filled grains per panicle (81.11) and the lowest sterility percentage (13.37) were recorded with colonization. Colonized plants irrigated at 30 mm CPE to a depth of 3 cm produced significantly superior productive tillers m-2 (275.00), filled grains per panicle (111.33) and the lowest sterility percentage (8.80). Among second order interactions, p1i1d2 produced significantly superior grain yield (2698.56 kg ha-1 ) and straw yield (2848.13kg ha-1 ). P. indica colonization, irrigation interval and depth of irrigation had significant effect on root parameters of rice at all stages of observation. P. indica colonized plants showed significantly superior rooting depth at all stages. Colonized rice plants irrigated at 35 mm CPE 157 to a depth of 3 cm revealed superior rooting depth viz., 19.4, 29.86 and 30.00 cm and average root length of 23.36, 34.87 and 36.20 cm at 30, 60 DAT and harvest respectively. Significantly superior root volume and root dry weight at 30, 45, 60 DAT and harvest respectively were recorded in colonized plants irrigated at 30 mm CPE to a depth of 3 cm. Among the physiological parameters studied, proline content declined in the order of decreasing CPE, 40 mm >35 mm > 30 mm. P. indica colonized plants irrigated at 40 mm CPE to a depth of 1.5 cm produced significantly greater proline (115.33 and 106.00 μmole g-1 at panicle initiation and flowering respectively). Colonized rice plants at 30 mm CPE to a depth of 3 cm observed the maximum relative leaf water content, cell membrane stability and chlorophyll stability index at panicle initiation and flowering respectively. P x I x D remained significant with the highest water use efficiency (WUE) of 3.47 kg ha-1mm-1 for P. indica colonized plants irrigated at 30 mm CPE to a depth of 3 cm. P. indica, irrigation interval and depth of irrigation could significantly influence the available nitrogen, phosphorus and potassium status of soil after experiment. Colonized plants irrigated at 40 mm CPE to a depth of 1.5 cm resulted in significantly superior available phosphorus (179.93 kg ha-1 ). Considering the economics, P. indica colonized plants irrigated at 30 mm CPE to a depth of 3 cm brought about the highest gross income (₹ 88951 ha-1 ), net income (₹ 30351 ha-1 ) and B: C ratio (1.51). Based on the above findings, it could be inferred that rice plants colonized with P. indica significantly enhanced the growth and yield attributes, root biomass, nutrient uptake and WUE, irrespective of interval and depth of irrigation.Yield and WUE of P. indica colonized plants subjected to severe stress, were observed to be equivalent to those of non-colonized plants under moderate stress. Colonization resulted in saving of 30 mm water or 3 irrigations and could help rice to combat drought stress by enhanced root biomass, nutrient uptake and water use efficiency during summer.
Molecular characterization of shattering in weedy rice (Oryza sative f. spontanea) biotypes of kerala
(Department of Plant Biotechnology, College of Agriculture, Vellayani, 2017) Shelvy, S; Ameena, M
The study entitled “Molecular characterization of shattering in weedy rice (Oryza sativa f. spontanea) biotypes of Kerala” was conducted at the Integrated Biotechnology Block, College of Agriculture, Vellayani, Thiruvananthapuram during 2015-2017. The objective of the study was isolation and sequencing of genes related to shattering viz. sh4 and qsh1 in weedy rice biotypes and characterization by expression profiling and phylogenetic analysis. Degenerate primers were designed for sh4 and qsh1 genes based on the gene sequences retrieved from NCBI database (sh4 and qsh1 forward and reverse primers) which were used to isolate and identify the genes. Both genomic DNA and Total RNA of weedy rice and cultivated rice Uma were isolated. PCR was done using both genomic DNA and cDNA. Amplification was obtained in two sets of designed primers i.e. sh4 (FW2 x RW2) and qsh1 (FW2 x RW2). When DNA was used as template for PCR, two of the sh4 primers and one of the qsh1 primers designed for shattering yielded amplicons at the expected size of 649bp, 696bp and 747bp respectively. PCR in cDNA samples of RNA amplicon of size ~690bp with the primer combination of sh4 (FW2 x RW2) in flag leaf was observed. Also, an amplicon of size ~750bp in flag leaf cDNA was produced using degenerate qsh1 FW2 x RW2 primers. None of these primers produced an amplification in any of the cDNA samples of cultivated rice Uma. The tBLASTx programme showed that the amplicon of size ~690bp was similar to shattering 4 (sh4) genes of Oryza populations, whereas the amplicon of size ~750bp belonged to qsh1 gene for putative transcription factor qsh1 of rice populations and mRNA of Oryza sativa japonica group. The result clearly revealed that the gene responsible for shattering viz., sh4 and qsh1 are present in both weedy rice and cultivated variety Uma as evidenced from the PCR amplification of genomic DNA. However, the genes responsible for shattering investigated in the present study viz., sh4 and qsh1 were not expressed in any of the growth stages in cultivated rice variety Uma. The NCBI conserved Domain Search programme, showed that the qsh1 FW2 x RW2 sequence of amplicon at ~750bp (obtained by reaction using weedy rice flag leaf cDNA) belonged to homeobox kn domain. The sequence of the amplicons of qsh1 obtained was the partial fragments of the first ever qsh1 gene for putative transcription factor qsh1 to be isolated from Oryza sativa f. spontanea. Phylogenetic tree constructed for sh4 FW2 x RW2 sequence, had highest similarity to shattering (sh4) gene of Oryza meridionalis voucher and also had relationship with Oryza rufipogon and Oryza sativa. However, the weedy rice qsh1 FW2 x RW2 query sequence was closely related to qsh1 gene of Oryza rufipogon, together with Oryza sativa indica group and Oryza sativa japonica group. Semi quantitative analysis with sh4 and qsh1 gene primers showed that the sh4 gene was expressed in flag leaf and grains and qsh1 gene was expressed only in the flag leaf. From this study it can be inferred that the gens responsible for shattering in weedy rice biotypes of Kerala viz. sh4 and qsh1 are present both in cultivated rice and weedy rice. However, the genes are expressed only in weedy rice during the flowering stage.
Performance evaluation of high yielding soybean varieties for summer rice fallows
(Department of agronomy, collegeof agriculture , Vellayani, 2023-12-01) Chinmaya Sahoo.; Ameena, M
The study entitled ‘Performance evaluation of high yielding soybean varieties for summer rice fallows’ was conducted at College of Agriculture, Vellayani during 2021-2023. The objective of the experiment was to assess the performance of high yielding soybean varieties under different land configurations in summer rice fallows. The field experiment was conducted at the Instructional Farm, Vellayani, during February to May 2023 in split plot design with three main plot treatments viz., broadbed and furrow (BBF) (l1), ridge and furrow (RAF) (l2) and flatbed method (l3); and six varieties viz., JS 9305 (v1), KDS 726 (v2), JS 2069 (v3), AISB 50 (v4), JS 335 (v5), Basara (v6) as sub plot treatments replicated four times. In BBF, raised beds were taken at a width of 120 cm with furrows of 15 cm width on both sides; in RAF, the ridges were made at a width of 30 cm with furrows in between and in the flatbed system, the land was levelled without any furrows on sides. Rhizobium inoculated seeds were dibbled at a spacing of 45 cm x 15 cm and the crop was managed as per the KAU Package of Practices. The results of the study revealed that the growth attributes were significantly influenced by land configuration methods and varieties. The BBF method and the variety JS 2069 produced taller plants throughout the growth stages. The highest leaf count was observed in BBF followed by RAF while KDS 726 and JS 2069 consistently produced higher leaf counts at all growth stages. Superior LAI was recorded by BBF up to 45 DAS. However, the values were comparable between l1(3.898, 3.579) and l2 (3.809, 3.434) at 60 DAS and at harvest respectively. The variety JS 2069 exhibited superior LAI (0.534, 1.810, 2.471, 4.284 respectively) at all the growth stages (15, 30, 45 DAS and at harvest) except at 60 DAS followed by KDS 726. The nodule count was higher for the variety AISB 50 (41.88) and was on par with JS 2069 (41.25), KDS 726 (40.52), and Basara (40), while JS 9305 had the lowest nodule count (35.78). Among the land configurations, BBF displayed the highest nodule fresh weight (0.850 g) while AISB 50 produced the highest nodule fresh weight (0.863 g) among the varieties tested. The varieties, AISB 50, JS 335, JS 9305, and Basara flowered early (37.73 to 40.65 days), while JS 2069 took the longest time (48.45 days), followed by KDS 726 (43.08 days). The BBF method yielded the highest pods per plant (53.36) and pod length (4.51 cm) followed by RAF (50.18 and 4.17 cm respectively). Among the varieties, JS 2069 produced the highest pod count (55.95 per plant) while JS 9305, KDS 726 and JS 2069 recorded higher pod length, pod weight and number of seeds per pod respectively. The variety JS 2069 recorded a higher pod yield per plant (31.71 g) and pod yield ha-1 (4932 kg) and was on par with KDS 726 (30.64 g, 4766 kg ha-1 ) and Basara (29.24 g, 4549 kg ha-1). AISB 50 had a lower pod count (42.95 per plant) and was on par with JS 9305 (44.98 per plant). The interaction between land configuration and varieties was found to be significant on pod weight where l3v5 recorded a higher pod weight (0.599 g). The BBF method produced the highest seed yield per plant (20.30 g) and seed yield ha-1 (2706 kg) with higher 100 seed weight (13.22 g), harvest index (HI) (0.404) and dry matter production per plant (DMP) (41.05 g). Among the varieties, JS 2069 recorded the highest seed yield per plant (24.61 g), seed yield ha-1 (3281 kg), HI (0.441) and DMP (48.94 g per plant). The haulm yield per plant and haulm yield ha-1 were found to be higher in KDS 726 (28.11 g, 4372 kg ha-1 respectively). Broad leaf weeds dominated the weed flora composition. The flatbed method had the highest weed density (19.12, 37.72, 40.72 m-2) and weed dry weight (17.74, 38.01, 53.16 g m-2) at all growth stages. Regarding quality parameters, the highest protein and oil contents were recorded for AISB 50 (41.97 %) and JS 9305 (20.10 %) respectively. The BBF method resulted in the highest N, P and K uptake (194.0, 10.55 and 123.41 kg ha-1 respectively), while the flatbed method had the lowest N, P and K uptake (150.33, 8.29, 93.04 kg ha-1 respectively). Among the varieties, JS 2069 recorded the highest N, P and K uptake (234.07, 13.43 and 156.40 kg ha-1 respectively). The BBF method resulted in a higher available N and K status while the highest available P (63.01 kg ha-1) was recorded in the flatbed method. Plants grown under the BBF method recorded a higher net income (₹82,913 ha-1) and B: C ratio (1.70) and were on par with the RAF method (₹74,579 ha-1). Among the varieties, JS 2069 registered the highest net income (₹1,11,171 ha-1) and B: C ratio (2.35). The study identified BBF as the most effective land configuration method and JS 2069 as the most suitable variety for soybean cultivation in summer rice fallows of Kerala based on growth and yield parameters. Considering the economics, either BBF or RAF method could be adopted as a suitable land configuration method for soybean cultivation in summer rice fallows. The variety JS 2069 under BBF could be identified as the most effective combination for realizing higher productivity for soybean cultivation in the summer rice fallows.
Performance of foxtail millet (Setaria italica L.) under varying shade levels
(Department of Agronomy, College of Agriculture, Vellayani, 2024-12-12) Shilpa, S; Ameena, M
An investigation entitled ‘Performance of foxtail millet (Setaria italica L.) under varying shade levels’ was undertaken at College of Agriculture, Vellayani, during 2022-2024. The major objectives were to identify foxtail millet (Setaria italica L.) varieties suitable for varying shade levels and to assess the effect of shade on growth, yield and quality of grains. The field experiment was carried out at the Instructional Farm, Vellayani, during the summer season spanning from January to April 2024. The experiment was laid out in split plot design with three shade levels (s1- 25 % shade, s2- 50 % shade and s3- open) as main plot treatments and seven foxtail millet varieties (v1- Renadu, v2 - Suryanandi, v3 – Garuda, v4 – Mahanandi, v5 - Narasimharaya, v6 - SiA 3156 and v7 - SiA 3085) as sub plot treatments with four replications. The recommended nutrient dose of 40:20:0 kg NPK ha-1 was applied as per ICAR IIMR recommendation. Among the growth attributes, shade levels had no significant influence on plant height, number of tillers per plant and number of leaves per tiller. Leaf area index (LAI) and dry matter production (DMP) enhanced under both the shade levels, and was found to be higher under 50 per cent shade level. Crop duration was shorter (78 days) under open condition compared to 25 per cent (78.81 days) and 50 per cent shade levels (80.66 days). Among the varieties, Garuda matured the earliest in 60.55 days. Mahanandi under 50 per cent shade level (s2v4) recorded taller plants, number of tillers per plant, number of leaves per tiller and LAI. DMP was found to be higher under 50 per cent shade with SiA 3156 (s2v6) on par with Renadu (s2v1) and Mahanandi (s2v4). The results of the study indicated a significant interaction between shade levels and varieties on the number of productive tillers per plant. SiA 3156 at 50 per cent shade produced higher productive tillers per plant (4.31) and was on par with Mahanandi at 25 per cent shade (3.61) and 50 per cent shade (3.26). Plants under 50 per cent shade produced the longest ear heads (17.68 cm) followed by open (16.88 cm) and 25 per cent (16.27cm). Grain yield per plant was found higher for SiA 3156 (11.93 g) and Mahanandi (11.53 g) at 50 per cent shade and Renadu at 25 per shade (11.20 g). Straw yield per plant was found higher for Renadu, SiA 3156 and Mahanandi at 50 per cent shade. Grain yield (2455.12 kg ha-1) and straw yield (3966.09 kg ha-1) showed significant increase under 50 per cent shade to the tune of 23 per cent and 20 per cent increase respectively, compared to grain yield (1997.41 kg ha-1) and straw yield (3280.79 kg ha-1) under open conditions. The quality parameters of foxtail millet grains were found to be significantly enhanced under 50 per cent shade, followed by 25 per cent. The content of crude protein (10.46%), total carbohydrate (61.68 mg 100g-1), crude fiber (3.79%), calcium (35.85 mg100g-1), zinc (3.24 mg100g-1), and iron (3.75 mg100g 1 ) were recorded higher at 50 per cent shade. Crude protein was significantly higher in Mahanandi and SiA 3156, while total carbohydrate levels were higher in Suryanandi, Mahanandi, SiA 3085, and SiA 3156, all under 50 per cent shade. The crude fibre was found to be superior in Mahanandi while Ca content was significantly higher in SiA 3085 both under 50 per cent shade. However, the Fe content was observed to be higher in SiA 3156 under 50 per cent shade level. The impact of shade levels on weed parameters was significant with lower weed dry weight under 50 per cent shade level at 60 DAS (5.05 g m-2) while the highest weed dry weight was noted under open conditions (11.26 g m-2). The total chlorophyll content was found to be enhanced under shaded situation. Total NPK content and NPK uptake by crop was influenced by the shade level with higher uptake under 50 per cent shade followed by 25 per cent shade. In contrast, the NPK removal by weeds was found to be lower under 50 per cent shade and comparable with 25 per cent shade. Among the interactions, the highest NPK uptake was noticed in SiA 3156 under 50 per cent shade level. Post- experiment soil analysis revealed higher electrical conductivity (0.18 dS mˉ¹) and organic carbon (0.54 %) in open condition. However, the available NP status was found to be superior in 25 per cent shade followed by 50 per cent shade. The net income and BCR was found to be higher for SiA 3156 and Mahanandi raised under 50 per cent shade and Renadu at 25 per cent shade level. The study identified SiA 3156 and Mahanandi as the most suitable foxtail millet varieties for cultivation under 50 per cent shade; Renadu for 25 per cent shade, while SiA 3085 and Suryanandi were ideal for open cultivation, based on growth, yield and quality parameters. Shaded conditions were found to enhance the growth, yield, and quality of foxtail millet grains during the summer season, in contrast to open field conditions.
Productivity enhancement of blackgram (Vigna mungo (L.) Hepper) intercropped in coconut gardens
(Department of Agronomy, College of Agriculture,Vellayani, 2021) Pooja, A P; Ameena, M
The research work entitled ‘Productivity enhancement of blackgram (Vigna mungo (L.) Hepper) intercropped in coconut gardens’ was undertaken at College of Agriculture, Vellayani during 2018-2021. The study aimed to identify shade tolerant blackgram varieties suitable for coconut gardens, to study the effect of foliar nutrition and plant growth regulators on growth and yield of the shade tolerant blackgram varieties intercropped in coconut garden and to work out the economics of cultivation. The investigation was carried out as two experiments: (i) screening of blackgram varieties for shade tolerance, and (ii) performance evaluation of shade tolerant varieties under foliar application of nutrients and growth regulators in rainfed coconut garden. The first experiment was conducted during Rabi 2019-20 in coconut garden having a light intensity equivalent to 50 per cent of that under open condition (56.25 klux), planted at a spacing of 7.6 m x 7.6 m. Seeds of 12 promising blackgram varieties collected from different research stations of south India (Sumanjana, DU 1, DBGV 5, VBN 5, VBN 6, VBN 8, Rashmi, CO 6, TAU 1, TAU 2, Blackgold and AKU 15) and three cultures (Culture 4.5.8, Culture 4.5.18 and Culture 4.6.1), were raised in micro plots laid out in randomized block design with three replications. The crop was raised as per KAU package of practices. The results of the study revealed significant variation in growth characters among the varieties screened for shade tolerance under partial shade in coconut garden. Plants of DBGV 5 were significantly taller (96.89 cm) with higher initial number of leaves at all the stages and was on par with Sumanjana and CO 6. Higher leaf area index (LAI) and leaf area duration were recorded in CO 6 (5.77, 65.66 days) and DBGV 5 (5.36, 58.40 days) followed by Sumanjana. Early flowering was observed in Sumanjana (34.33 days) and DBGV 5 (36.33 days). The variety DBGV 5 had the highest photosynthetic rate and resulted in significantly more pods per plant (23.67) which was on par with CO 6, VBN 5, VBN 6, Sumanjana and Rashmi. DBGV 5 produced the highest seed yield per plant (5.44 g) followed by VBN 5 and Sumanjana. Haulm yield per plant was higher for DBGV 5 (19 g) and was on par with VBN 5, Sumanjana and CO 6. The variety DBGV 5 produced the highest seed yield (1183 kg ha-1 ) followed by VBN 5, Sumanjana and CO 6. A higher harvest index of 0.24 was recorded by Sumanjana which was on par with DBGV 5 and VBN 6. Among the varieties screened, five varieties which performed better in terms of yield per unit area under the partial shade in coconut garden viz., DBGV 5, VBN 5, Sumanjana, CO 6 and VBN 6 were selected for experiment II undertaken in summer 2020 followed by the confirmatory trial during Rabi 2020 -21. The experiment was laid out in split plot design with five varieties (v1 - Sumanjana, v2 - DBGV 5,v3 - VBN 5,v4 - VBN 6,v5 - CO 6) as main plot treatments and six foliar sprays of nutrients and plant growth regulators as subplot treatments (f1: 19:19:19 (1%) at 45 and 60 DAS, f2: SOP (0.5%) at 45 and 60 DAS, f3: NAA 40 mg L-1 and salicylic acid 100 mg L-1 at pre-flowering (30-45 DAS) and 15 days later, f4: f3 + f1, f5: f3 + f2 and f6: Control - KAU POP). Among the varieties, Sumanjana (v1) grew taller during both the seasons and was comparable with CO 6 and DBGV 5 at harvest. Sumanjana produced higher number of branches with more number of leaves during both the seasons. At flowering, higher LAI, number and dry weight of nodules per plant were realized by Sumanjana and was on par with CO 6 (v5) in summer and DBGV 5 (v2) in Rabi. Sumanjana exhibited the highest crop growth rate (CGR) and relative growth rate (RGR) during both the seasons at 45-60 DAS. However, DBGV 5 recorded the highest net assimilation rate (NAR) between 30-45 DAS and 45-60 DAS during both the seasons. The highest chlorophyll content was recorded by DBGV 5 (1.96 mg g-1 fresh tissue) during summer and by Sumanjana (2.36 mg g-1 fresh tissue) during Rabi. The highest stomatal conductance (30.22 m moles m-2 s -1 and 28.34 m moles m-2 s -1 ) and lower stomatal index (15.16% and 13.34%) were recorded in Sumanjana during both the seasons. The variety Sumanjana flowered earlier compared to other varieties during both the seasons and produced the highest number of pods per plant (27.30 and 26.54). Hundred seed weight was significantly higher for DBGV 5 (5.01 g and 4.92 g) and remained at par with Sumanjana (4.99 g and 4.88 g) during both the seasons. Seed yield, haulm yield and total dry matter production (TDMP) were higher for Sumanjana and comparable with DBGV 5 during both the seasons. Sumanjana recorded higher NPK uptake during both the seasons followed by DBGV 5. The subplot factor foliar spray had significant effect on growth, physiological and yield attributes of blackgram varieties. Foliar spray of 19:19:19 (1%) at 45 and 60 DAS + foliar spray of NAA 40 mg L-1 and SA 100 mg L-1 at pre-flowering and 15 days later (f4) resulted in significantly taller plants, more number of branches and leaves. The highest CGR, RGR (at 45-60 DAS), LAI, number and dry weight of nodules per plant at flowering were recorded in f4 during both the seasons. During summer, f3, f4 and f5 recorded higher NAR between 45-60 DAS. Higher chlorophyll content and stomatal conductance were recorded by f4 during both the seasons. Plants supplied with f3 attained 50 per cent flowering earlier and was on par with f5 during both the seasons. Highest number of pods per plant, 100 seed weight, seed yield, haulm yield and TDMP were recorded by f4 during both seasons. The grain protein content was improved by f4 and was on par with f3, f1 and f5. The NPK uptake was higher in f4 and was on par with f3 and f5 during summer. Significantly higher organic carbon, available N and P was recorded in f4. Among the treatment combinations, Sumanjana (v1) with f4 produced taller plants at two months after sowing (MAS), higher number of branches and leaves per plant during summer and Rabi. Leaf area index, number of nodules and dry weight of nodules at flowering were higher for v1f4 followed by v2f4. Sumanjana in combination with f4 measured significantly higher CGR and RGR (at active growth stages), highest chlorophyll content, stomatal conductance and lower stomatal index during both the seasons. The variety Sumanjana with f4 produced superior number of pods per plant (30.24 and 29.40) and hundred seed weight during summer and Rabi. A higher seed yield was realized in v1f4 (1750 kg ha-1 ) which was on par with v2f4 (1713 kg ha-1 ) during summer. Seed yield was the highest (1700 kg ha-1 ) in v1f4 during Rabi. Haulm yield and TDMP recorded were higher for v1f4 and was on par with v2f4 during both the seasons. The available N status in soil was higher during both the seasons in v1f4 with the highest NPK uptake during Rabi. Sumanjana and DBGV 5 with f4 realized higher mean net income (₹ 70411 ha-1 and ₹ 61256 ha-1 ) and mean B: C ratio (2.04 and 1.95). The present study identified DBGV 5 and Sumanjana as shade tolerant blackgram varieties with superior growth and yield attributes under partial shade and could be recommended for intercropping in coconut garden. Further, the yield of the shade tolerant varieties could be enhanced by recommended dose of nutrients as per KAU package supplemented with foliar spray of 19:19:19 (1%) at 45 and 60 DAS + foliar spray of NAA 40 mg L-1 and SA 100 mg L-1 at preflowering (35 DAS) and 15 days later. Sumanjana and DBGV 5 raised under partial shade in coconut garden with recommended dose of nutrients supplemented with the above said foliar spray realized higher mean net income and mean B: C ratio.
Standardisation of growth media and organic nutrient schedule for container cultivation of spinach beet (Beta vulgaris var. bengalensis)
(Department of Agronomy, College of Agriculture, Vellayani, 2020) Aisha Majeed; Ameena, M