Nutrient economy through seed coating with vermicompost in cowpea

Abstract

An investigation was carried out at the Instructional Farm, attached to the College of Agriculture, Vellayani to evaluate "Nutrient economy through seed coating with vermicompost in cowpea". The experiment was laid out in Completely Randomised Design with nine treatments and three replications. The variety used was Kanakamoni. The treatments include coating of seeds with Rhizobium, vermicompost and a combination of both and also uncoated seeds supplied with either farmyard manure or vermicompost as organic source. Biometric observations like height of plant, number of leaves, seedling girth and number of fruiting branches were not significantly influenced by any of the treatments. However, root characters like root length, root spread and number of effective nodules were found to be significantly influenced by the different treatments. Coating of seeds with vermicompost significantly influenced the grain yield of cowpea and also the number of pods plant-l. Coating seeds with vermicompost combined with the application of full inorganic fertilizers and farmyard manure as organic source recorded the highest grain yield. From the analysis of grain samples, it is inferred that only K and Ca content of grain was significantly influenced by the different treatments.

Phosphorus solubilisation capacity of soil was not significantly influenced by any of the treatments. N fixing capacity of soil was significantly influenced by the vermicompost coating of seeds during 30 DAS and 45 DAS. Soil analysis for available nutrients revealed that the different treatments had significant influence on the Ca, Mg, Zn, Cu and Mn content in soil. Use of vermicompost coated seeds produced the maximum uptake of N, P and K at maximum flowering stage and at harvest. Soil application of vermicompost recorded the highest uptake of Ca, Mg, Cu and Mn during maximum flowering stage. Plant analysis for nutrient content indicated that the content of all the nutrients except P was significantly influenced by the different treatments during maximum flowering stage. Yield was positively and significantly correlated with the height of plant, root characters and availability and uptake of nutrients. In the present study, a superiority is shown by vermicompost inoculated plants where farmyard manure was given as the organic source indicating that at times of scarcity of vermicompost, seed treatment could serve the purpose.