Browsing by Author "Prameela, P"

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Biosurfactants for sustainable soil management
(Department of Agronomy, College of Horticulture, Vellanikkara, 2020) Nengparmoi, Th; Prameela, P
Compatibility of multinutrient mix sampoorna with herbicides for rice
(Department of Agronomy, College of Agriculture , Vellanikkara, 2024) Akhila, P; Prameela, P
Tank mixing of agrochemicals is a common practise among farmers in order to save labour, time and application cost. However, mixing is done without having a scientific knowledge on effect of tank mixing. Tank mixing of agrochemicals may result in synergistic, antagonistic, or neutral effects on efficacies of chemicals involved. Herbicidal weed control is very common in rice as it is the economically viable and easy method. Usually post emergence herbicides are applied at 15-20 days of sowing or transplanting. There is a possibility of tank mixed spraying if the herbicides are compatible with Sampoorna. Hence a research programme entitled “Compatibility of multinutrient mix Sampoorna with herbicides for rice” was conducted during July to November 2022 to evaluate the weed control efficiency and compatibility of few post emergence herbicides with Sampoorna KAU multimix in transplanted wetland rice. Experiment consisted of thirteen treatments which included application of five herbicides at recommended rates (bispyribac sodium @ 0.03 kg/ ha, cyhalofop butyl @ 0.08 kg/ ha, 2,4-D @ 0.8 kg/ ha and premix herbicides AlmixⓇ (premix of metsulfuron methyl and chlorimuron ethyl) @ 0.004 kg/ ha and Vivaya Ⓡ (premix of cyhalofop butyl and penoxsulam) @ 0.15 kg/ ha. Respective tank mixed applications with Sampoorna KAU multimix @ 10 g/L were also included along with hand weeded plots with or without Sampoorna and unweeded check. The design was RBD replicated thrice and the variety was Uma. Spraying was given 50 days after transplanting. Phytotoxicity to crop was observed third and seventh day after spraying. Growth and yield attributes of crop were studied and weed parameters like weed count and weed dry matter production were also recorded. Phytotoxicity to rice was observed with tank mix application of 2,4- D+ Sampoorna. Brown spots on leaves and yellowing were noticed by third day itself. The symptoms reduced by 7 days after spraying as new leaves were free of toxicity. This also led to reduction in chlorophyll content at panicle initiation and heading stages. The chlorophyll content at PI stage in 2,4-D + Sampoorna was 2.94 mg/g fresh weight where s in 2,4-D alone spray it was 3.42 mg/. In all other treatments Sampoorna application resulted in slight increase in chlorophyll content. In the case of AlmixⓇ + Sampoorna though visual phytotoxicity symptoms were not present, reduction in plant height was noticed. Reduction in plant height in 2, 4-D+ Sampoorna was 17 % and 10 % at 30 and 60 days after transplanting respectively, compared to its sole application. While AlmixⓇ+ Sampoorna resulted in 13 % and 6 % reduction at 30 DAT and 60 DAT respectively. Individual application of herbicides resulted in comparable tiller counts with respect to their Sampoorna- tank mixed applications except in the case of 2, 4-D and AlmixⓇ at 60 DAT. Similar trend was noticed in number of productive tillers, grain yield and straw yield where all herbicides except 2, 4-D and AlmixⓇ registered higher values with tank mixed application with Sampoorna. Grain yield in 2,4-D+ Sampoorna was 15 percent lower than 2,4-D alone and corresponding reduction in AlmixⓇ+ Sampoorna was 8 percent. In the case of bispyribac sodium, cyhalofop butyl and premix cyhalofop+ penoxsulam, the sole application and tank mix registered comparable grain and straw yields and the grain yield ranged from 5444 to 5647 kg/ ha. Hand weeded plots registered the lowest weed dry matter at all stages. Sole application as well as tank mixed application of all herbicides were comparable in weed dry matter production and weed control efficiency. The weed dry matter in unweeded plot was 1373 kg/ ha whereas the values ranged from 150 kg/ha to 203 kg/ ha in all other treatments, indicating that tank mixing herbicides with Sampoorna has not adversely affected efficiency of herbicides. With respect to effect of Sampoorna application on grain yield of rice, the effect was not very conspicuous as the soil experimental field was not deficient with respect to micro nutrient status. The grain yields in hand weeded plots as well as well as hand weeded+ Sampoorna were comparable with grain yield of 5686 kg/ ha and 5722 kg/ ha respectively.2,4-D+ Sampoorna followed by AlmixⓇ with Sampoorna registered yield reduction of 21 percent and 14 percent compared to hand weeding+ Sampoorna spray which registered higher yield of 5722 kg/ ha. Among tank mixed combinations of herbicides and Sampoorna, 2, 4-D registered the lowest N and K uptake on tank mixing with Sampoorna followed by tank mix application of AlmixⓇ with Sampoorna. All other treatments registered comparable P uptake values except unweeded control, which was the inferior to others. It can be concluded that few post emergence herbicides for rice weed control ie; bispyribac sodium, cyhalofop butyl and VivayaⓇ (premix of cyhalofop butyl and penoxsulam) can be recommended for tank mix application with KAU Sampoorna as foliar spray at 15-20 days after sowing or transplanting. 2,4-D and AlmixⓇ are not compatible with Sampoorna and hence are not suitable for tank mix application.
Crop intensification and stress tolerance in hybrid napier
(Department of Agronomy, College of Agriculture ,Vellanikkara, 2024-03-07) Akhila, C Thampi.; Prameela, P
Hybrid Napier (Pennisetum glaucum X Pennisetum purpureum) is a popular fodder grass among dairy farmers of Kerala due to its high production potential. However, there is a significant gap between fodder demand and supply, given the limited land availability in the State. Expanding fodder cultivation through crop intensification with the inclusion of fodder legumes in the existing cropping system is a viable option to boost fodder production and quality. Understanding the salt and flood tolerance of hybrid napier can help the farmers select suitable cultivars for coastal and flood-prone areas, to ensure fodder availability. In this context, an investigation entitled ‘Crop intensification and stress tolerance in hybrid napier’ was conducted at the Agronomy Farm, Department of Agronomy, College of Agriculture, Vellanikkara, Kerala from 2019 to 2021. The objectives were to assess the suitability of intercropping legumes with hybrid napier, its effect on growth, yield, quality, as well as soil health, and to study the response of a few popular hybrid napier cultivars to salinity stress and short-term flooding. The investigation comprised of three experiments (i) the production potential of hybrid napier-based legume intercropping systems (ii) tolerance of high-yielding hybrid napier cultivars to salinity stress and (iii) tolerance of high-yielding hybrid napier cultivars to short-term flooding. The field experiment on hybrid napier-based legume intercropping systems (HN+legume) was conducted during the two-year period from 2019 to 2021. It was laid out in randomized block design with four replications. The treatments consisted of hybrid napier in normal rows (60cm x 60cm) (T1), hybrid napier in paired rows (45/90cm) (T2), HN in paired rows + fodder cowpea (T3), HN in paired rows + stylosanthes (T4) and HN in paired rows + horse gram (T5). Three additional treatments of sole crops of fodder cowpea (T6), stylosanthes (Stylosanthes guianensis) (T7), and horse gram (T8) were included for comparison of production efficiency in the intercropping system under study. The results of the study indicate the possibility of intercropping hybrid napier planted in paired rows with legumes, in Kerala. Among the legumes, stylosanthes were the most suitable in terms of yield, net profit, and B-C ratio. Varieties IGFRI-3 and CO-3 were found inherently tolerant to mild levels of salinity stress compared to CO-5 and Suguna. Considering fodder yield, varieties CO-5 was found better suited to areas amenable to shortterm flooding (3-4 cm water depth, up to 15 days), and flooding immediately after harvesting was identified as the susceptible stage.
Efficacy of new post-emergence herbicides for rice
(Department of Agronomy, College of Horticulture, Vellanikkara, 2012) Syama S Menon; Prameela, P
Weeds are the major problem in rice production. Manual removal of weeds is laborious and due to labour shortage and high cost of labour, farmers are resorting to chemical weed control. Many new molecules of selective herbicides are now coming in the market which are having broad spectrum activity or effectiveness against a group of weeds. The present study was conducted to evaluate the relative efficacy of some of these herbicides in wet land rice culture. The experiment was conducted at Alappad Kole in farmer’s field during October 2011 to February 2012. The treatments included application of graminicides alone ( metamifop, fenoxaprop p-ethyl, cyhalofop-butyl); graminicides with follow up application of herbicides to kill non grass weeds (cyhalofop-butyl fb Almix, metamifop fb carfentrazone ethyl, metamifop fb Almix, fenoxaprop p-ethyl fb Almix, fenoxaprop p-ethyl fb ethoxysulfuron) and herbicides with broad spectrum activity (bispyribac sodium, penoxsulam and azimsulfuron). Hand weeded and unweeded controls were also included for effective comparison. All herbicides in the study were post emergent in action and were sprayed at 20 DAS. Observations on weeds as well as crop were taken at 30 DAS, 60 DAS and at harvest. Visual phytotoxicity scoring on rice as well as on weeds was done at three and seven days after spraying. As revealed by the weed spectrum in unweeded control, grasses were the dominant weeds than sedges and broad leaved weeds. Among grasses, Echinochloa stagnina and Echinochloa crusgalli among sedges Fimbristylis miliacea, Cyperus iria and Cyperus difformis and in broad leaved weeds Lindernia crustacea and Ludwigia perennis were the dominant weed species. Sedges and broad leaved weeds were present in treatments applied with graminicides alone at 30 DAS. At 60 DAS and at harvest, higher weed population was observed compared to 30 DAS. Bispyribac sodium, cyhalofop-butyl+Almix and fenoxaprop p-ethyl+Almix continued to perform better in terms of weed control as evidenced by low weed dry matter production both at 60 DAS and at harvest. N, P and K uptake by weeds at different stages of crop followed the same trend as that of weed dry matter production. Among various herbicides or herbicide combinations only carfentrazone ethyl applied treatment showed phytotoxicity to rice. The variations in plant height among treatments were significant only at 30 DAS and the tallest plants with 54 cm height were observed in unweeded control. However, there was a slight reduction in the height of rice in plots applied with Almix, fenoxaprop p-ethyl and bispyribac sodium compared to hand weeded control, though visual phytotoxicity symptoms were not expressed. The highest number of panicles/m2, filled grains per panicle as well as grain yield was registered in hand weeded control. Cyhalofop-butyl+Almix and fenoxaprop p-ethyl+Almix were on par with respect to grain yield and recorded comparable yield with that of hand weeding. Cyhalofop-butyl+Almix and fenoxaprop p-ethyl+Almix also registered low weed index of 5.2 (for both) and high weed control efficiency of 88 and 90 percent, respectively. From this study it can be concluded that, cyhalofop-butyl followed by Almix or fenoxaprop p-ethyl followed by Almix or bispyribac sodium alone can be recommended for effective post emergence weed control and higher yield in wet seeded rice. If grasses are the predominant weeds, cyhalofop-butyl or fenoxaprop p-ethyl alone without follow up spray of Almix can also be recommended.
Efficacy of pre-emergence herbicides in weedy rice management
(Department of Agronomy, College of Agriculture, Vellanikkara, 2024-12-30) Hilal Mohamed; Prameela, P
Fertigation in sprinkler irrigated upland rice (Oryza sativa L.)
(Department of Agronomy, College of Horticulture, Vellanikkara, 2015) Shahanila, P P; Prameela, P
Herbicidal management of stem hemiparasite Dendrophthoe spp. in mango orchards
(Department of Agronomy, College of Agriculture, Vellanikkara, 2025) Revathi, C; Prameela, P
Dendrophthoe falcata (Loranthus), a stem hemiparasite of the Loranthaceae family, is a problematic weed in tree crops, including mango. Manual removal of this parasitic weed is the common practice, often involving cutting the infested tree branches. However, it is labour- intensive, often ineffective, and requires repeated intervention due to persistent sub-epidermal haustoria. Even herbicidal sprays for selective control are not available, and use of conventional spraying methods often results in toxicity to the host. Recent technologies such as air-assisted and electrostatic sprayers offer low-volume and target-specific applications with improved canopy penetration and more efficacy. Under this background a study entitled “Herbicidal management of stem hemi-parasite Dendrophthoe spp. in mango orchards” was carried out at the College of Agriculture, Vellanikkara, Thrissur, from October 2024 to September 2025 with the objectives, to assess the efficacy of various herbicides against Dendrophthoe spp. and to evaluate sprayers that can enhance the application efficiency of herbicides for effective management of loranthus. The experiment was carried out on 20-25-year-old mango trees in College Orchard that had been infested with Dendrophthoe falcata for 8-10 years. Treatments were 2,4-D Na salt 80% WP (5 g/L), 2,4-D amine 58% SL (10 mL/L), 2,4-D Na salt (5 g/L) + CuSO₄ (20 g/L), glufosinate ammonium 13.5% SL (10 mL/L), metribuzin 70% WP (5 g/L), ethrel 39% SL (25 mL/L), and metsulfuron methyl 20% WP (0.4 g/L) as targeted foliar sprays. Basal banding (padding) of 2,4-D Na salt (2%) and metribuzin (2%) was also included along with manual removal and unsprayed check. Phytotoxicity symptoms on the parasite and host were observed. In loranthus, changes in biochemical and physiological parameters, nutrient content of leaves, and regrowth up to one year after treatment were assessed. Four types of sprayers, i.e., battery-powered hydraulic, air-assisted, electrostatic, and air compression sprayers, were evaluated by comparing deposition efficiency, weed control efficacy, spray volume requirement, and cost of weed control in order to identify the most efficient technology for targeted herbicide delivery to loranthus clusters. Among the herbicides, though ethrel induced the fastest response through leaf abscission of parasitic weed by two days after spraying (DAS), total control was not obtained and regrowth started by 40 DAS. In metsulfuron methyl sprayed treatments regrowth started by 60 days, while metribuzin sprayed loranthus showed regrowth by 40 days. Foliar application of 2,4-D Na salt and 2,4-D amine provided the most effective and prolonged suppression without any regrowth even up to one year, which indicated complete drying of the parasite without any adverse effect on the host. Manual removal failed to suppress regrowth beyond 3 months. Herbicidal sprays markedly impaired leaf metabolism too. A drastic reduction in total soluble sugars (from 15.26 to 7.63 mg/g), protein (2.28 to 1.79 mg/g), relative leaf water content (50 to 11%), membrane stability (56 to 26%), and chlorophyll (1.64 to 0.92 mg/g) was observed. The NPK content in loranthus leaves also showed a sharp decline. These effects were linked to oxidative stress, disrupted carbohydrate translocation, and accelerated chlorophyll degradation. In contrast, padding with 2,4-D Na salt and metribuzin maintained higher physiological and biochemical values, indicating localized action with minimal systemic translocation and hence ineffectiveness. Significant variation was observed in droplet deposition efficiency among sprayer types, with electrostatic sprayers having the highest deposition (30.5 μL/cm²), followed by air- assisted (12.63 μL/cm²), battery-powered hydraulic (10.0 μL/cm²), and air-compression sprayers (7.23 μL/cm²). Advanced spraying technologies, particularly electrostatic and air- assisted sprayers, reduced spray volume requirement to nearly one-tenth of that used by conventional sprayers. Interestingly, a comparison between droplet deposition rate and weed control efficiency of battery-powered hydraulic and electrostatic sprayers revealed an inverse relationship, wherein higher deposition did not lead to enhanced herbicidal activity. This discrepancy is attributable to the parameters such as spray volume, droplet size, and lethal dose necessary for effective herbicide performance, ensuring adequate wetting, absorption, and translocation to facilitate metabolic action within the host-parasite system. It can be concluded that targeted foliar application of 2,4-D Na salt (80% WP) @5 g/L or 2,4-D amine (58% SL) @10 mL/L, using battery-powered hydraulic sprayer, is an effective method to manage Dendrophthoe infestation in mango orchards
High density planting and seed tuber size on productivity enhancement of lesser yam[Dioscorea esculenta (Lour.) Burkill)
(Department of Agronomy, College of Horticulture, Vellanikkara, 2019) Anasooya Sebastian; Prameela, P
Management of high temperature stress in aerobic rice(oryaza sativa L.)
(Department of Agronomy, College of Horticulture, Vellanikkara, 2020) Saravana Kumar, M; Prameela, P
Nutrient Management in arrowroot (Maranta arundinacea L.)
(Department of Agronomy, College of Agriculture, Vellanikkara, 2025-01-14) Mohsina, O V; Prameela, P
Nutrients and tillage interactions in rice fallow cowpea (Vigna unguiculata L. Walp.) production
(Department of Agronomy, College of Agriculture, 2020) Vandana G Pai; Prameela, P
Perfomance of high yielding varieties of finger millet [Eleusine coracana (L.)] (Gaertn)
(Department of Agronomy, College of Agriculture, Vellanikkara, 2020) Kishore, Neeruganti; Prameela, P
Potassium utilization efficiency and seasonal response in photosynthates partitioning of high yielding sweet potato varieties
(Department of Agronomy, College of Agriculture ,Vellanikkara, 2023-05-19) Jeena Mary; Prameela, P
Potassium-magnesium interaction in coleus [Solenostemon rotundifolius (Poir.) J.K. Morton] productivity
(Department of Agronomy, College of Agriculture, Vellanikkara, 2021) Aswani, S; Prameela, P
An experiment entitled ‘Potassium-magnesium interaction in coleus [Solenostemon rotundifolius (Poir.) J.K.Morton] productivity’ was conducted during the period from July to November 2020 at Agronomy Farm, College of Agriculture, Vellanikkara, Thrissur, with the objective to assess the effect of potassium and magnesium sulphate application on tuber yield of coleus. Potassium (K2O) was applied @ 60 kg/ha (soil test based), 100 kg/ha (PoP recommendation) and a check (no potassium). Magnesium sulphate doses tried were 0 kg/ha, 10 kg/ha, 20 kg/ha, 40 kg/ha. The treatments consisted of twelve different combinations of K2O and magnesium sulphate which was replicated thrice in RBD design. The soil of the experimental field was medium in potassium and low in magnesium status. Magnesium sulphate was soil applied at 30 days of planting and in the case of lower dose of 10 kg/ha, it was foliar applied (2 per cent spray). N and P2O5 were applied as per PoP recommendation of 60:60 kg/ha. Coleus variety Nidhi was used for the study. Growth parameters such as plant height, dry matter production of aerial portion, dry matter production of tubers as well as total dry matter production were significantly influenced by potassium application. However, LAI and root to shoot ratio at vegetative stage did not vary significantly with potassium dose. Taller plants were observed with potassium application @ 60 and 100 kg/ha at 60 DAP.But at 90 DAP lower value of plant height was registered at higher level of 100 kg/ha K2O. Magnesium sulphate application also influenced plant height at 90 DAP taller plants were observed in plants which received 40 kg/ha of MgSO4. Varied levels of potassium as well as magnesium sulphate did not bring about variation in chlorophyll content of coleus leaves. However, interaction of potassium and magnesium sulphate on leaf chlorophyll content was significant and higher values were observed when K2O was applied @ 60 kg/ha along with MgSO4 @ 20 or 40 kg/ha. Dry matter production (DMP) of aerial portion increased with increasing levels of K2O. At 60 DAP and at harvest plants which received 60 or 100 kg/ha potassium registered higher and comparable aerial DMP. Magnesium sulphate application did not show any significant influence on DMP at 90 DAP. However at harvest, aerial DMP with the application of 40 kg magnesium sulphate was superior to other levels which were at par statistically. Tuber yield showed significant increase with increase in rate of potassium applied and showed an increase of 19 per cent when 100 kg of K2O was applied compared to control (13.80, 14.94 and 16.46 t/ha, at 0, 60 & 100 kg/ha K2O, respectively). Various levels of magnesium sulphate applied did not show any influence on tuber yield. However interaction effect of K and Mg was significant and best combination was 60 K2O with 40 kg MgSO4, 100 kg K2O with 10 or 40 kg magnesium sulphate, which registered statistically comparable yields. Magnesium and potassium levels had no influence on yield of unmarketable tuber. Application of K2O @ 100 kg/ha recorded higher DMP of tuber and total DMP over 0 and 60 kg potassium. Effect of magnesium sulphate application on dry matter production of tuber and total dry matter production was non significant. However interaction effect of potassium and magnesium sulphate was significant with respect to tuber DMP. Higher and superior values were registered under 100 kg of K2O with 10 kg MgSO4 and 40 kg MgSO4. Higher K uptake was noticed when K2O was applied @ 60 kg/ha with 40 kg/ha MgSO4 which was on par with K2O at 100 kg/ha with MgSO4 at 10 kg/ha or 40 kg/ha. Potassium and magnesium sulphate application did not cause significant variation in N, P and secondary nutrient uptake by coleus. Net returns as well as B-C ratio were higher for K2O application @ 100 kg/ha along with MgSO4 @ 40 kg/ha or 10 kg/ha. The results of the study indicate that for better productivity in coleus, potassium may be applied at the rate of @ 100 kg/ha, even in soils with medium status of available K. Also, K- Mg balance is important and hence in soils deficient in magnesium and medium in potassium, soil application of magnesium sulphate @ 40 kg/ha or foliar spray @ 10 kg/ha at 30 DAP, together with K2O dose of 100 kg/ha can enhance the productivity of coleus.
Production potential of cereal fodder crops under various tillage practices in rice fallows.
(Department of Agronomy, College of Horticulture, Vellanikkara, 2011) Gintu George; Prameela, P
In order to test the feasibility of raising cereal fodders in rice fallows under various tillage systems an experiment entitled “Production potential of cereal fodder crops under various tillage practices in rice fallows” was conducted at the Department of Agronomy, College of Horticulture, Vellanikkara, Thrissur, Kerala. The experiment was laid out in split plot design with four replications during the period from November 2009 to February 2010. The main plots had tillage practices as treatments which included zero tillage with and without herbicide application (M1 and M2), minimum tillage (M3) and normal tillage (M4). The subplots had three treatments, viz., fodder cereals; maize (S1), sorghum (S2) and bajra (S3). Analysis of data on herbage yield of the three fodders under different tillage practices showed that the herbicide based zero tillage, minimum tillage and normal tillage practices resulted in comparable yields (20.72, 18.72 and 18.08 t/ha). Zero tillage without herbicide application resulted in significantly lower yield (11.69 t/ha). Growth parameters like plant height, leaf area index, leaf stem ratio, shoot root ratio etc. recorded at various growth stages also showed the favourable influence of minimum and herbicide based zero tillage on plant growth. Among the cereal fodders, maize recorded significantly higher yield of 20.19 t/ha followed by sorghum with 15.91 t/ha and bajra with 15.81 t/ha. Considering tillage practices and crops together, the highest B: C ratio of 3.31 was realized when maize was grown under herbicide based zero tillage closely followed by maize under minimum tillage with a B: C ratio of 3.24. Of the other two crops, bajra was found to be more profitable than sorghum. Like maize, herbicide based zero tillage resulted in a higher B: C ratio (3.0) for bajra than other tillage treatments. The yield reduction in zero tillage without herbicide application was mainly due to weeds. A study of weed spectrum showed that dicots were the major weed flora followed by grasses and sedges. The weed population and weed dry matter production were the highest in zero tillage without herbicide application followed by minimum and herbicide based tillage and the least was in normal tillage. Weed dry matter production in zero tilled without herbicide plot was 1545 kg/ha compared to a much lower dry matter accumulation of 193 kg/ha in normal tillage plot. The silage made from all the three cereal fodders was found to be of good quality with golden yellow colour, pleasant smell and a pH ranging from 3.8 to 4.2. In silage prepared without the addition of molasses, pH was found to be slightly higher (4.2) compared to silage prepared with molasses as additive (3.9). The study revealed that fodder maize under herbicide based zero tillage was the best with regard to yield and B: C ratio. However, for a herbicide free production system, maize grown under minimum tillage is preferred due to its equally good performance.
Response of high yielding varieties of pearl millet (Pennisetum glaucum (L.) R. Br.) to major nutrients
(Department of Agronomy, College of Agriculture, Vellanikkara, 2021) Murshida, S; Prameela, P
Pearl millet or bajra is a major millet grown in the tropics for both food and fodder. Many high yielding varieties of pearl millet are now available for cultivation. But, the performance of these varieties and the nutrient requirement of pearl millet were not assessed in Kerala. Hence, the study entitled “Response of high yielding varieties of pearl millet [Pennisetum glaucum (L.) R. Br.] to major nutrients” was carried out with the objective of assessing the performance of selected prominent high yielding varieties of pearl millet and their response to major nutrients. The experiment was carried out at Agronomy Farm, Department of Agronomy, College of Agriculture, Vellanikkara during the period from November, 2020 to February 2021. Treatments were the combinations of nutrient levels (N: P 2 O 5: K 2 O @ 60: 30: 30, 70: 35: 35, 90: 45: 45 kg/ha and absolute control) and four varieties released from various research institutes [Co (Cu) 9, Co 10, ABV 04 and Dhanashakthi]. The design was factorial RBD with 16 treatments and three replications. The biometric parameters like plant height, length and width of leaf blade, Leaf Area Index and dry matter production of pearl millet were significantly influenced by the application of different N: P 2 O 5: K 2 O levels. The plants which got higher fertilizer doses of 90: 45: 45 and 70: 35: 35 N: P 2 O 5: K 2 O kg/ha had taller plants and registered higher dry matter production. The variety Co (Cu) 9 was taller with more leaf area index and dry matter production whereas, Dhanashakthi was inferior. But, it had superior leaf width and leaf-stem ratio. The application of fertilizers had a significant influence on grain yield, yield parameters and straw yield of bajra. The highest grain weight per earhead (36.93 g) and grain yield (3360 kg/ha) were registered in plants that received 90: 45: 45 N: P 2 O 5: K 2 O kg/ha. The grain yield at fertilizer level of 90: 45: 45 N: P 2 O 5: K 2 O kg/ha showed only a marginal increase of 7.5 per cent compared to 70: 35: 35 N: P 2 O 5: K 2 O kg/ha (3107kg/ha). The straw yield at 90: 45: 45 and 70: 35: 35 N: P 2 O 5: K 2 O kg/ha were comparable (10391 and 10753 kg/ha, respectively). 1The varieties ABV 04, Co 10 and Dhanashakthi had superior and comparable grain yield ranging from 3026 to 3188kg/ha and the performance of Co (Cu) 9 was inferior with 2201kg/ha. Lower straw yield was noticed in variety Dhanashakthi (6430 kg/ha) that was comparable to Co 10 (8096kg/ha). The other two varieties ABV 04 and Co (Cu) 9 registered superior straw yield of 10191 and 11390 kg/ha, respectively. The longest earhead was for variety Co (Cu) 9 and the shortest was for variety Dhanashakthi (19.44 cm). The lowest weight of grains per earhead (29.27 g) and test weight (7.99 g) were recorded for variety Co (Cu) 9. The variety Dhanashakthi had higher test weight (13.35 g) as well as Harvest Index (0.34). The straw yield was comparable in varieties Co (Cu) 9 (11,390 kg/ha) and ABV 04 (10,191 kg/ha). The average crude protein content was 11.37 per cent and the varietal differences were non-significant. Crude fiber was comparable in ABV 04, Dhanashakthi and Co (Cu) 9 with an average content of 2.33 per cent. The crude fiber content at varied levels of primary nutrients were comparable. The highest and superior nitrogen uptake was recorded by the application of 90: 45: 45 N: P 2 O 5: K 2 O kg/ha (437 kg/ha) with 51 per cent increase compared to absolute control. P uptake at 90: 45: 45 N: P 2 O 5: K 2 O kg/ha (126 kg/ha) was on par to that at 70:35:35 N: P 2 O 5: K 2 O level. But, K uptake was comparable at three N: P 2 O 5: K 2 O levels with an average of 358 kg/ha. Significantly lower uptake of primary nutrients were registered in absolute control. The application of fertilizers enhanced the gross and net returns along with benefit- cost ratio in pearl millet cultivation. The highest B: C ratio (1.78) and net returns (Rs. 53,186 /ha) from bajra cultivation registered in N: P 2 O 5: K 2 O level of 70: 35: 35 N: P 2 O 5: K 2 O kg/ha, followed by the highest dose. Hence, it can be concluded that a fertilizer dose of 70: 35: 35 N: P 2 O 5: K 2 O kg/ha can be recommended for pearl millet cultivation in Kerala. The varieties ABV 04, Co 10 and Dhanashakthi can be recommended for grain purpose, whereas varieties Co (Cu) 9 and ABV 04 are ideal for straw and fresh herbage. ABV 04 is a good variety with respect to both grain and straw yield.
Response of sweet potato [Ipomoea batatas (L.) Lam.] to secondary nutrients
(Department of Agronomy, College of Horticulture, Vellanikkara, 2020) Nengparmoi, TH; Prameela, P
Screening of different morphotypes of colocasia for shade tolerance
(Department of Agronomy, College of Horticulture, Vellanikkara, 1990) Prameela, P; Vikraman Nair, R
The present study 'Screening of different morphotypes of colocasia for shade tolerance' was conducted during May 1989 to June 1990 at the College of Horticulture, Vellanikkara , Thrissur, Kerala, India . The experiment was laid out in a split plot design with four replications. Eleven morphotypes of colocasia were raised at shade levels of about 0, 25, 50 and 75 per cent. For providing shade, pandals were erected on wooden frames and covered with unplaited coconut fronds to provide required levels of shade. These were covered on all sides also leaving a clearance of 1 m from ground level. L I -190 SA Quantum Sensor and LI-191 SA Line Quantum Sensor were used for adjusting the shade intensities approximately to the desired levels. Most of the colocasia morphotypes recorded the highest yield at 25 per cent shade and hence this crop is to be classed as shade loving. However there were substantial differences in varietal responses to shade and in the morphotypes M1 , M7, M8, M9 , M10, M12 and Sree Rashmi yields were higher under shaded condition than in the open. In M2, M15, M16 and M17 yields were higher in the open and there was steady decline with increasing shade intensity. Harvest index and drymatter accumulation were found to be the highest under 25 per cent shade level in most of the morphotypes. But the highest starch and oxalic acid contents were in the tubers from the open. Six morphotypes M1, M2, M10, M15, M16 and M17 were selected as generally superior for all shade situations.
Tank mix application of cyhalofop-butyl with selected herbicides for weed control in wet seeded rice
(Department of Agronomy, College of Horticulture, Vellanikkara, 2016) Atheena, A; Prameela, P
Weed management in ash gourd (Benincasa hispida (Thunb.) Cogn.)
(Department of Agronomy, College of Horticulture, Vellanikkara, 2014) Sajeera C Chathoth; Prameela, P