Browsing by Author "John, P S"

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Ammonium and nitrate release pattern from residue incorporated rice soils
(Kerala Agricultural University, 1999) Beena Jacob; Mercy George; John, P S
Biomass production of green ganure crops and mineralization of organic nitrogen in coconut basins
(Department of Agronomy, College of Horticulture, Vellanikkara, 1995) Tanie Thomas; John, P S
An investigation on biomass accumulation of green manure crops and mineralization of organic nitrogen in coconut basins was conducted at the College of Horticulture, Vellanikkara during 1993-94. The experiment was aimed at evaluating the performance of various green manures and cover crops grown in coconut basins based on their biomass accumulation, nutrient accretion and nitrogen dynamics in the soil after incorporation. The mineralization pattern of green manure in red and laterite soils was studied in a laboratory incubation study using 15N labelled green manure. The salient results of the investigation are abstracted below. Crotolaria striata which represented the neglected green manures and pueraria phaseoloides which represented the cover crops produces the maximum dry matter in coconut basins. The popular green manure Crotolaria junecea failed to grew and put forth good biomass accumulation under coconut. The highest N content was found to be with Pueraria. Cassia tora was found to be the richest source of P. The maximum K content was reported in Cassia tora and Sesbania aculeata. Pueraria phaseoloides and Crotolaria striata released the maximum quality of nitrogen to the soil. The ammonium-N accumulation was found to be high in the upper layer of 0 to 15 cm soil when compared to the 0 to 30 cm soil layer. Crotolaria striata and Pueraria released the highest amounts of ammonium-N. In the release of nitrate-N, Pueraria was found to be the most efficient closely followed by Crotolaria striata. In the case of total mineral N (ammonium+nitrate) content the highest quantity was extracted with Crotolaria striata followed by Pueraria. In the incubation experiment to study the pattern of mineralization green manure N, the N release in terms of 15NH4 extracted during different periods of incubation was the highest for Crotolaria striata followed by Sesbania aculeata. The mineralization of green manure 15N took place at a lower rate in laterite soil when compared to red soil.
Combined application of granular preparations of pre-emergent herbicides and fertilizers in rice
(Department of Agronomy, College of Horticulture, Vellanikkara, 1995) Bindu, N K; John, P S
A field experiment was conducted at the Agricultural Research Station, Mannuthy under the Kerala Agricultural University during the first crop season of 1994 to find out the effect of pre-emergent herbicides and fertilizers in rice. The experiment was laid out in a randomized block design and consisted of fourteen treatments with three replications. Broadleaved weeds and sedges dominated the field. Among broadleaved weeds, Mono choria vaginalis and sphenocleazeylanica were predomint. Shoenoplectus lateriflorus and Cyperus difformis were the prominent sedges present in the field and Echinochloa colonum,saccolepis interrrupta and Isachne miliacea were the important grasses present. Butachlor, anilofos and oxyflourfen under different methods of application reduced the weed Population. Though oxyflourfen recorded high weed control efficiency, it was highly phytotoxic to the rice crop and resulted in poor crop stand. Butachlor and anilofos applied as homemade granular (GP) preparation or as spray alone, or in combination with fertilizer was safe to the crop. The available nutrient in the soil was not affected by the different methods of application of butachlor and anilofos, alone or when combined with fertilizer. Butachlor and anilofos as spray or as GP applied alone, or in combination with fertilizer recorded similar crop growth characteristics, yield and yield attributes. Nutrient up taken by weeds was lower in butachlor and anilofos treatment. Lower weed index values were recorded in butachlor and anilofos treatment. The highest return per rupee was obtained from anilofos treatments. The highest return per rupees was obtained from anilofos treatments. In general, combined application of anilofos or butachlor GP with fertilizer gave efficient control of weed, produced higher grain yields and high return per rupee invested. It also reduced cost, energy and time of weed control operation.
Combined application of green manure and amophos on P nutrition and yield of rice
(Kerala Agricultural University, 1999) Pushpa Joseph; Mercy George; John, P S
Effect of application of 2,4-Dd mixed with urea in low-land direct sown rice
(Kerala Agricultural University, 1989) John, P S; Sadanandan, N
Effect of calcium peroxide coating of rice seeds and water regimes on germination of rice seeds and weed growth
(Kerala Agricultural University, 1986) Nair, M S; Sasidharan, N K; John, P S
Effect of joint application of 2,4-D and urea on weed control in rice
(Kerala Agricultural University, 1995) John, P S; Sadanandan, N
In a field experiment to study the efficiency of joint broadcast application of herbicide 2,4-D and fertilizer urea as compared to spraying 2,4-D and broadcasting urea in two separate operations, it was observed that both these methods are similar in weed control and rice yield. However, in the joint application the sprayer is not needed and the spraying cost, human energy and time spent for spraying are saved.
Effect of potash nutrition on infestation by the yellow borer Tryporyza Incertulas
(Kerala Agricultural University, 1980) John, P S; Thomas, M J
Efficiency of foliar and soil applied nutrients in irrigated rice
(Department of Agronomy, College of Horticulture, Vellanikkara, 2015) Sreedhu P Preman; John, P S
Growth and yield of cashew in relation to foliar and soil nutrient levels
(Department of Agronomy, College of Horticulture, Vellanikkara, 1992) Latha, A; John, P S
An experiment on the growth and yield of cashew in relation to foliar and soil nutrient levels was conducted during 1990-'92 by making use of seedling progenies of BLA-39-4 with three levels each of N (250, 500 and 1000 g /tree /year), P (125, 250 and 500 g P205 /tree /year) and K (250, 500 and 1000 g K2O /tree /year) and one absolute control (with out NPK application ). Significant response in increasing height and number of flushes was observed only for N (500 g /tree /year) and P (250 g P205 /tree / year). Leaf N and K content at flushing , flowering and fruiting were enhanced by application on of a ll the three nutrients with maximum values at flowering . Leaf P content was enhanced by N, P and K application only at flushing and fruiting . N, P and K application also increased the chlorophyll ‘ b 1 and total chlorophyll. There was increase In N and P content of soil by N, P and K application , while K content of s oil was increased only with higher levels of K. 2 The number of panicles/m and test weight of nuts and yield were increased by the application of N, P and K. A positive significant relationship was obtained between leaf N and P contents at flowering and fruiting stages and yield . There was progressive increase in nut volume , protein content of kernels and fruit characters such as fruit weight, fruit volume and TSS of apple by N, P and K application .
Nutritional constraints of rice -legume system in laterite soils of humid tropics
(Department of Agronomy, College of Horticulture, Vellanikkara, 2002) Gracy Mathew; John, P S
A research programme entitled "Nutritional constraints of rice- legume system in laterite soils of humid tropics" was carried out from 1997-'98 to'1999- '00 at Regional Agricultural Research Station, Pattambi. The objectives of the programme were to study the effect of crop residue recycling, nutrient management practices and tillage and water management practices on soil and plant elemental status and productivity of rice- rice-legume cropping system There were two experiments in the programme. The first experiment entitled, "Soil- plant elemental status and productivity as influenced by crop residue recycling and nutrient supply in the rice-legume cropping system" was taken up to study the impact of nutrient management practices as well as crop residue recycling on soil productivity and crop growth. The crop residues added in the system involved harvested left overs of grain cowpea crop during summer as well as addition of two-third portion of straw of kharif crop to rabi season crop. Silica at 250 kg ha", higher K dose of 70 kg ha-I and soiVfoliar supply of Mg, Zn, Cu, B and Mo were also included in various treatment combinations. The treatments exhibited significant influence on grain and straw yield. The treatment which did not receive any inorganic fertilizers registered the lowest yield during all the seasons. Straw addition did not' bring about yield advantage in kharif, but in rabi there was steady and significant increase over the seasons. Silica application was not beneficial in initial seasons, but from fourth rice crop onwards, significant increase was noticed. Though there was an improvement in organic carbon of soil during some seasons, summer cowpea raising did not bring about specific yield improvement. The absence of response to addition of summer cowpea residues revealed that either lack of N or a lower level of organic carbon may not be the limiting factors for low yield in these laterite soils. Potassium application even at the higher dose of 70 kg ha-I was "found to have no appreciable effect on growth and yield of paddy. Foliar application of boron and molybdenum and soil as well as foliar spray of Mg, Zn and CLl continuously for five seasons did not bring about any significant influence on growth and yield of paddy The second experiment, " Effect of tillage and water management practices on soil-plant, elemental status and productivity of rice in rice- rice legume cropping system" was aimed to study the influence of deep ploughing and intermittent drainage. Deep ploughing during kharif season had no significant influence during the current season or for the following rabi crop indicating that in puddled soil condition deep ploughing will not be of much advantage. The two water management practices did not produce any appreciable difference in growth or yield of the crops during the kharif seasons; 'but it adversely affected the performance of rabi 1999-'00 crop which could be due to , the dry atmospheric condition during the season. During rabi 1998-'99, the desiccating effect was considerably low and hence the drainage did not affect the growth of the crop. Hence the effect of intermittent drainage depends on season as well as the current weather situation. The elemental composition of the plant showed that there was no deficiency of any of the elements analysed in the plant system and hence the general low yield obtained from these soils could be due to nutritional constraints owing to excesses, imbalances or metabolic unavailability of elements. The plant had high content of non-applied elements particularly Fe. This excess absorption -of iron might be due to the high content of available iron in the soil. The absorbed nutrients, particularly N was not effectively utilized for grain production as evidenced by the relatively high content of 0.9 per cent N in straw as against 1.1 per cent in grain. Management practices like addition of cowpea residues, supply of nutrients, adoption of deep tillage or intermittent drainage did not show any advantage. Recycling of paddy straw as well as continuous addition of silica were effective in improving yield.
Nutritional resource use efficiency in rice production
(Department of Agronomy, College of Horticulture, Vellanikkara, 2004) Vallal Kannan, S; John, P S
The chemical constraints for higher yields in laterite soils are identified as low cation exchange capacity and organic matter content, high acidity, iron and aluminium toxicity, high phosphorous fixation and poor nutrient status. Investigations carried out to identify the limiting factors and their mode of action in laterite soil revealed direct effect of excess iron absorption, their metabolic interference, unfavourable Ca + Mg / K ratio, and deficiency of certain elements manifested as negative effects of some others. Management of organic manuring modified by amelioration with suitable amendments was reported to be an ideal remedial measure for reducing the above chemical constraints. An experiment was conducted at Agricultural Research Station, Mannuthy during 2001-2002, to characterize and quantify the effect of organic sources on nutrient supply, amelioration and inactivation of the deleterious factors in rice , culture and to study the supplementary requirements of inputs and complementary effects on yield improvement. It was also intended to develop a technology by integrating various inputs and their levels to ensure high resource use efficiency and consequently higher productivity. The plant height and tiller production was highest in the treatment green manure + lime + ash at active t.illering, panicle initiation and 50 per cent flowering. The total dry matter production was highest in the green manuring + lime and green manuring + lime + ash treatment. All the growth parameters such as plant height, tiller count and total dry matter production showed a stepwise improvement with doubling of K, doubling of K along with addition of lime and ash and doubling of K with addition of lime, ash and sulphur over the treatment where K was given at normal rate and without any ameliorants. The highest chlorophyll content both 'a' and ob' was found as resulted in the fallow - green leaf manure treatment, however, this was not reflected in the process of yield formation since the highest yield was observed for the treatment, green manure + lime + ash. The favourable cell sap pH around 6.21 was observed in the treatment green manure + lime + ash which resulted in the highest grain and straw yield. The highest grain and straw yield of 6.64 and 6.75 t ha-I, respectively was observed in the treatment combination green manure + lime + ash x N as NH4S04 + half P + lime + ash + double dose of K which indicate the importance of addition of lime, ash and sulphur as ammonium sulphate in the fertilizer package of rice in laterite soil. The following conclusionsare drawn from the results of the experiment. In the mundakan - summer - virippu rice cropping system in laterite soil leaving the land fallow' during summer may considerably reduce the yield during virippu if not supplemented with adequate organic manure and ameliorants like lime and ash. If the summer season is kept fallow, green leaf manu ring could be a better substitute for addition of organic matter to the laterite soil. Paddy straw incorporation at 15 days before the virippu cropping in laterite soil was found to reduce the yield of virippu rice probably due to high rate of immobilization ofN. The increase in acidity and consequent higher solubilization and uptake of Fe in virippu crop was evidently due to summer fallow which favour natural oxidation of Fe and Mn. Ameliorants like lime and ash added both during summer green manuring and virippu rice crop enhanced the rice growth and yield through modification of pH, supplementation of potash and calcium. Enhancement ofN:K ratio to 1: 1 was found to enhance rice productivity in laterite soil. Addition of K application did not increase the K content in the plant but reduced Fe uptake. Changing the N source to ammomum sulphate and thereby sulphur I fertilization was found to increase growth and yield of rice. Ammonium sulphate treatment helped mainly to increase plant height but not tiller production. Among yield attributes spikelet production was very much influenced by sulphur fertilization. The physiological and uptake efficiency of the N derived from green manuring was higher compared to other organic sources and consequently resulted in better agronomic efficiency. This indicates the need for a green manure - rice system in laterite soil to enhance soil and crop productivity. The green manured rice with ameliorants such as lime and ash, and ammonium sulphate as N and S source resulted in the highest net return and B:C ratio of2.25.
Phosphate and potash fertilisation of rice in the clay loam soils of Kuttanad
(Kerala Agricultural University, 1979) Ittyavirah, P J; Nair, S S; Sankara Panicker, K; John, P S
A field experiment was conducted at the Rice Research Station, Moncompu to assess whether rice crop can be raised without continuous application of phosphorus and potash in the clay loam soils of Kuttanad. The variety used wasTriveni. Results revealed that skipping of potash during the alternate seasons is not affecting the yield, end hence csn be adopted for economising ihe expenditure. Skipping of phosphorus is having depressing effect on yieid. Application of nitrogen alone without phosphorus and potash has shown significant reduction in yield, and the crop exhibited typical symptoms of phosphate deficiency.
Productivity of cashew as influenced by chlorophyll and leaf nitrogen content
(Kerala Agricultural University, 1994) Latha, A; John, P S; Mercy George; Krishnan, S
Productivity of rice in laterite soil in relation to nitrogen-sulphur interaction
(Department of Agronomy, College of Horticulture, Vellanikkara, 2010) Rathish, S T; John, P S
The research programme entitled “Productivity of rice in laterite soil in relation to nitrogen - sulphur interaction” was conducted mainly to study the nitrogen and sulphur availability and their interaction as influenced by organic manure sources, particularly straw incorporation in rice cultivation. The “Mineralization pattern of nitrogen and sulphur” was studied in pot culture experiment at College of Horticulture, Vellanikkara during the rabi season (Mundakan) Sep 2007 – Feb 08. “Response of rice to nitrogen and sulphur mineralization from organic matter with varying C:N ratios” was studied in farmers field, Pudhunagaram, Palakkad during the rabi seasons (Mundakan) Sep 2006 – Feb 07 and Sep 2007 – Feb 08. The mineralization of nitrogen and sulphur from the organic materials was influenced by time after application. The straw incorporated treatment released noticeably lower amount of nitrogen and sulphur in the initial stages than no manure application. The early growth characters of rice such as plant height, tiller production and dry matter production were significantly lower in straw incorporated treatments. Straw incorporation followed by application of nitrogen and sulphur or both, did not make any significant change in growth pattern probably due to inadequacy or improper timing. Increasing levels of nitrogen and sulphur positively influenced the vegetative growth and yield. The interactive effects of manures × N/S were significant for several characters. Beneficial effects of higher nitrogen and sulphur with straw incorporation were less evident in the early stages and was pronounced in the later stages. Nitrogen application with cow dung showed better performance during vegetative stage, but declined towards harvest. The tiller decline was lower in the straw incorporated treatments than either cow dung applied or unmanured treatments. Yield attributing characters were significantly influenced by incorporation of straw and cow dung along with nitrogen and sulphur. Grain yield increased from 3432 kg ha-1 in the absolute control to 7085 kg in the straw + N90 + S30 treatment in first year and from 3657 kg to 7116 kg in the cow dung + N90 + S30 treatment in second year. The interaction effects of manures × N/S were more pronounced than N × S. Combined application of organic manures and nitrogen noticeably increased protein nitrogen and protein sulphur content. Most of the plant nutrients were positively correlated with each other and positively correlated with grain yield. N × Fe and S × Fe have showed significant negative correlation. Agronomic efficiency of nitrogen or sulphur (kg grain/kg nutrient applied) was not influenced by organic manure application. Apparent recovery of nitrogen as well as physiological efficiency of nitrogen was the highest in combination of organic manures with 45 kg nitrogen and 30 kg sulphur. The utilization or physiological efficiency was also highest (kg grain/kg nutrient taken up) for the above combination. Straw incorporation resulted in long term maintenance of soil fertility as evidenced by higher mineral nitrogen and sulphur in soil upto a period of 110 days. In sulphur deficient soil, sulphur fertilizers could increase the rice yield and the use efficiency of nitrogen. The finding of the study points to beneficial effects of rice straw left in the field after harvesting using combine harvesters. However 37 to 52 kg ha-1 less mineral N was observed in the straw incorporated soil during the 30 days after incorporation and 20 days after rice planting compared to cow dung, both incorporated at 10 t ha-1. If this deficit could be compensated by N added at appropriate time, the straw will be a better and cheaper source of organic matter than cow dung.
Productivity of rice in relation to nitrogen management
(Kerala Agricultural University, 1994) John, P S; Mercy George; Latha, A
Productivity of rice in relation to nitrogen management
(Kerala Agricultural University, 1994) John, P S; Mercy George; Latha, A
Relative efficiency of ameliorants on rice productivity in lateritic soils of Kerala
(Department of Agronomy, College of Horticulture, Vellanikkara, 2014) Anila, M A; John, P S
The correction of soil pH, reduction of toxic accumulation of native elements and supplementation of secondary nutrients may enhance the growth and productivity of rice grown in lateritic lowlands. A field study was conducted during January to May, 2013 at the rice field of College of Horticulture, Vellanikkara to evaluate the response of soil ameliorants on growth and yield of rice. The experimental design was RBD with 3 replications.Transplanted Jyothi was grown at 15 cm x 10 cm spacing in 5.0 m x 4.0 m plots. The soil was having an initial pH of 5.3. The treatments were amelioration of soil with different amendments such as CaO, dolomite, and ‘Mangalasetright’, which is a commercial product. The ameliorants were applied with or without fertilizer. The package of practices recommendation for low land rice, an absolute control treatment and fertilizer only treatment were also included for effective comparison. Nitrogen and potassium were applied in three equal split doses, first as basal dressing, second at tillering stage and the third at panicle initiation stage. The full dose of phosphorus was applied as basal dressing. CaO @ 377 kg ha -1 together with FYM and NPK, and ‘Mangalasetright’ @ 375 to 774 kg ha -1 constantly maintained a pH of more than 6, which is considered good for rice.Soil amelioration significantly increased the growth characters of rice such as height and tiller count in the presence or absence of fertilizers.Higher doses of ‘Mangalasetright’ resulted in significantly higher LAI than its lower doses.Application of CaO @ 377 kg ha -1 or ‘Mangalasetright’ @ 500 to 774 kg ha-1 together with fertilizer application also resulted in significantly higher improvement in root weight, root spread and leaf chlorophyll content.The leaf chlorophyll content was improved due to the combined effect of soil amelioration, organic manure addition and fertilizer application.The treatment which received the recommended POP for rice cultivation resulted in the constant improvement in rice dry matter production at all the growth stages, which was significantly highest.‘Mangalasetright’ at all the doses and CaO @ 377 kg ha -1 with fertilizer application have produced similar dry matter at 60 DAT and harvest than non application of ameliorants. Ameliorants other than dolomite created a favorable soil environment with an optimum pH and nutrient content which resulted in greater nutrient uptake by crop and consequent development of chlorophyll, enhanced photosynthesis and ultimately higher dry matter production. Amelioration improved all the yield attributes and consequently the yield. Among different ameliorants ‘Mangalasetright performed better than CaO and the lowest effect was observed for dolomite.The highest dose of ‘Mangalasetright’ and the treatment which received POP recommendation resulted in the highest and similar yield of 6.7 t ha-1. The superiority of ‘Mangalasetright’ even in the absence of organic manure addition is attributed to its Mg and S contents. The enhanced growth and yield characters of rice observed in the ameliorated treatments are due to the favorable nutritional rhizosphere environment in the soil and consequent nutrient availability and uptake. While CaO did the ameliorative function ‘Mangalasetright’ did both soil amelioration and secondary nutrient supplementation.
Response of cashew to nutrient application in laterite soil
(Kerala Agricultural University, 1996) Latha, R A; Mercy George; John, P S
The response of cashew grown in laterite soil to long term application of nutrients at different levels was studied in terms of yield attributing characters and yield. The quadratic response in yield observed with increasing levels of individual primary nutrients necessitated the estimation of optimum economic dose and were worked out to be 748 g N, 329 g P,O5 and 765 g K,O per tree per year.
Seasonal variation in elemental composition of cocoa litter under shaded and open conditions
(Kerala Agricultural University, Vellanikara, 2001) Sreekala, N V; Mercy, George; John, P S; Vikraman Nair, R