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2011 - 20152
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Subject: Soil Science and Agriculture Chemistry × Author: KAU × Author: Mariya Dainy, M S × End date: 2016 × Start date: 2011 × Type: Thesis ×
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    ThesisItemOpen Access
    Nitrogen and sulphur interaction on their release pattern and use efficiency in ferralitic soils.
    (Department of Soil Science and Agricultural Chemistry,College of Agriculture, Vellayani, 2011) Mariya Dainy, M S; KAU; Usha, P B
    An experiment was carried out at College of Agriculture, Vellayani to investigate the interactive effect of nitrogen and sulphur on their release pattern and use efficiency in ferralitic soils with bhindi as the test crop. The experiment consisted of an incubation study and a field experiment. The incubation study was carried out to understand the release pattern of N and S from their sources viz. urea and gypsum in the soil at different sampling stages (30 and 100 days of incubation) using ferralitic soil kept at field capacity. The treatments consisted of M1N1S1, MINIS2 , M1N1S3 , M1N2S1 , M1N2S2 ,M1N2S3 ,M1N3S1 , M1N3S2 , M1N3S3 , M2N1S1 , M2N1S2 , M2N1S3 , M2N2S1 , M2N2S2 , M2N2S3 , M2N3S1 , M2N3S2 and M2N3S3 and M0N0S0 . Levels of N include N1 (50 kg ha-1), N2 (80 kg ha-1) and N3 (110 kg ha-1). M1 include P2O5 @ 8 kg ha-1+ K2O @ 25kg ha-1 (current POP) and M2 include P2O5 @ 35 kgha-1 + K2O @ 70 kg ha-1(modified POP). Different levels of S are S1 (10 kg ha-1), S2 (15 kg ha-1) and S3 (20 kg ha-1). Soil samples were collected and analyzed for pH, available N and available S content. There was increase in pH value to the neutral range at fifty per cent flowering stage (30 Days of Incubation) and all the treatments showed a decreasing trend in the pH value at 100 Days of Incubation. Available N and available S content increased to some extent at fifty per cent flowering and decreased at the final harvest stage. Application of N up to 110 kg ha-1 significantly increased the available N status of soil and S application up to 20 kg ha-1 increased the soil S status during incubation. The field experiment was laid out in 2×3×3+1 factorial RBD having three replications using bhindi variety Varsha Uphar as the test crop. The treatments were similar to that of the incubation study. S application @15 kg ha-1 significantly reduced the internodal length. N and S interaction N @ 80 kg ha-1 and S @ 15 kg ha-1 showed significant influence on fruit length. The maximum number of fruits and highest yield was obtained when the nutrients were applied @ 80 kg N ha-1 + 8 kg P2O5 ha-1 + 25 kg K2O ha-1 + 15 kg S ha-1. Considering the N and S interaction effects, combined application of N @ 80 kg ha-1 and S @ 20 kg ha-1 increased the number of fruits and yield. Application of N up to 80 kg ha-1 increased the crop yield and above this level, there was reduction in yield. The increase in number of fruits per plant by the application of N and S may be due to the highest uptake and efficient utilization of nutrients. N @ 110 kg ha-1 and S @ 20 kg ha-1 recorded the highest dry matter content. S application @ 15 kg ha-1 showed significant influence on N Use Efficiency (NUE) in bhindi. Application of 80 kg N ha-1 + 8 kg P2O5 ha-1 + 25 kg K2O ha-1 + 15 kg S ha-1 resulted in highest NUE. By the application of urea and gypsum, there was slight increase in the soil pH. After N and S application, there was increase in organic carbon content of the soil. At fifty per cent flowering all the nutrients showed an increase in availability and there was a decrease at the final harvest stage because of crop uptake and various losses. N application @ 110 kg ha-1 significantly increased the available N status in the soil. S application up to 20 kg ha-1 significantly increased the available P K and S content in soil. As the levels S increased, there was increase in the exchangeable calcium in soil. Higher levels of application of N recorded higher N content in both plant and fruit. Application of P and K at M2 (35 kg P2O5 ha-1 + 70 kg K2O ha-1) level significantly increased the content of P, K and Ca in plant and fruit. Increased S application increased the Ca content in plant since gypsum was used as the source of S. S application up to 20 kg ha-1 had significant influence on the fruit Ca and Mg concentration. The interactive effect of N and S was not significant in the case of S content in plant. But, N2S3 (N @ 80 kg ha-1 and S @ 20 kg ha-1) recorded the superior value. N application had got positive influence on the content of P, K, Ca, Mg and S in plant and fruit. By progressive increase in S application up to 20 kg ha-1and N application up to 80 kg ha-1, there was significant reduction in N: S ratio. N and S fertilization had significant influence on leaf chlorophyll content and application of 80 kg N ha-1, 35 kg P2O5 ha-1, 70 kg K2O ha-1 and 15 kg S ha-1 showed the superior value for chlorophyll content. An increasing trend was noticed with higher levels of N up to 80 kg ha-1 and S up to 20 kg ha-1. N and S application significantly enhanced the uptake of nutrients. Uptake of phosphorus, potassium, calcium, magnesium and S were highest when N, P, K and S were applied @ 80 kg N ha-1+ 35 kg P2O5 ha-1+ 70 kg K2O ha-1+ 20 kg S ha-1. N application @ 80 kg ha-1 significantly influenced the B: C ratio. Among the treatments M1N2S2 (80 kg N ha-1 + 8 kg P2O5 ha-1 + 25 kg K2O ha-1 + 15 kg S ha-1) which gave the highest yield showed the highest B: C ratio. Maximum B: C ratio was obtained when N and S were applied @ 80 kg ha-1 and 15 kg ha-1 respectively. As the levels of S increased, B: C ratio also increased. Fertilization of N, P, K and S @ 80 kg ha-1, 35 kg ha-1, 70 kg ha-1 and 15 kg ha-1 respectively recorded the minimum Percentage Disease Incidence (yellow vein mosaic). Among the treatments, yield, number of fruits per plant, N Use Efficiency and B: C ratio were highest for M1N2S2 (80 kg N ha-1 + 8 kg P2O5 ha-1 + 25 kg K2O ha-1 + 15 kg S ha-1) and it can be considered as the best treatment combination. Application of N significantly increased the yield and the yield was highest at N2 level (80 kg N ha-1). There was reduction in yield if we apply N @ 110 kg ha-1. By the application of S along with N increased the NUE and we can reduce the dose of N to 80 kg ha-1 instead of 110 kg N ha-1 for bhindi.
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    ThesisItemOpen Access
    Investigations on the efficacy of biochar from tender coconut husk for enhanced crop production
    (Department of soil science and agricultural chemistry, College of agriculture, Vellayani, 2015) Mariya Dainy, M S; KAU; Usha, P B
    An investigation was carried out at College of Agriculture, Vellayani to characterize biochar from tender coconut husk and to assess its effects on soil properties, growth and yield of yard long bean (Vigna unguiculata subsp. sesquipedalis). The experiment consisted of production and characterization of biochar, laboratory experiments on nutrient sorption- desorption studies, carbon dioxide emission studies and a field experiment. Biochar was produced from tender coconut husk by the process of pyrolysis and it was crushed, sieved and the 2 mm sieved samples were used for further studies. The produced biochar had an alkaline pH (9.13), high CEC (15.26 cmol kg-1) and C: N ratio (68.86). Electrical Conductivity, total C, N, P, K, Ca, Mg and S contents in the prepared biochar were 1.73 dS m-1, 72.3 per cent, 1.05 per cent, 0.38 per cent, 2.27 per cent, 0.40 per cent, 0.20 per cent and 0.27 per cent respectively. The produced biochar recorded very high water holding capacity (226 per cent), low bulk density (0.14 Mg m-3) and high Brunauer Emmett Teller surface area (157.93 m² g-1) A laboratory experiment was conducted to study the desorption and sorption of nutrients like N, P, K, Ca, Mg, S, Fe, Mn, Zn and Cu using biochar. 32.35 per cent NH4+, 75.65 per cent PO42-, 45.14 per cent K+, 46.00 per cent Ca2+, 23.45 per cent Mg2+, 74.38 per cent SO42-, 36.80 per cent Fe2+, 30.20 per cent Mn2+, 26.75 per cent Zn2+ and 26.72 per cent Cu2+ were found to be desorbed from biochar after 7 rinses using de-ionized water in 1:100 ratio. The highest per cent of nutrient desorbed was P (75.65 per cent), followed by S (74.38 per cent) and the lowest per cent of nutrients desorbed were Zn (26.75 per cent) and Cu (26.72 per cent) within 72 hours. Sorption experiments were performed using rinsed biochar at different concentrations of nutrients and at different time intervals in 1:100 ratio. The results of the study indicated that biochar could sorb 100 per cent NH4+, 90.70 per cent PO42-, 92.00 per cent K+, 87.00 per cent Ca2+, 86.15 per cent Mg2+ and 91.82 per cent SO42- when it was equilibrated with 100ppm solutions within 24hours. For micronutrients, when 50 mg l-1 Fe2+, Mn2+, Zn2+ and Cu2+ solutions were given, biochar could sorb 99.67 per cent, 100 per cent, 99.12 per cent and 99.12 per cent respectively. Biochar from tender coconut husk is a good sorber and slow releaser of nutrients. An incubation study was carried out to estimate and study the pattern of carbon dioxide emission by the application of biochar into soil and it was compared with that of common organic amendments viz. FYM and vermicompost. The experiment consisted of 7 treatments with 3 replications and the study revealed that the cumulative amount of carbon dioxide emitted was highest for FYM @ 2 per cent (1014.05 mg CO2 100 g-1) and biochar @ 2 per cent registered an emission of 87.17 mg CO2 100 g-1 after 6months of incubation. There observed 91.40 per cent reduction in CO2 emission when soil was incubated with biochar @ 2 per cent compared to 2 per cent FYM. A field experiment was carried out with biochar and other commonly used organic manures at different doses using yard long bean variety Vellayani Jyothika as the test crop during January 2013 to April 2013, at the Instructional farm, College of Agriculture, Vellayani. Yield (1358 g plant-1) and yield attributes like pod length (54.50 cm), pod girth (3.90 cm), number of pods per plant (51), nutrient uptake and B: C ratio were significantly superior for the treatment T8 which received biochar @ 20 t ha-1 with 2 per cent PGPR and NPK as per POP. Physical properties chemical properties of the soil were significantly improved by the application of biochar @ 30 t ha-1. Biochar application reduced the bulk density, increased water holding capacity, water stable aggregates, pH, Cation Exchange Capacity, organic carbon status and nutrient availability. From the investigations, it can be concluded that application of biochar @ 20 t ha-1 along with 2 per cent PGPR and NPK as per POP which resulted in the yield of 1358 g plant-1 (20.12 t ha-1) can be considered as the economically viable and the best treatment. Biochar from tender coconut husk can be used as a good soil amendment which can improve soil health and enhance crop production.