Integrated nutrient management for enhancing productivity and profitability of long-duration pigeonpea (Cajanus cajan) under rainfed condition

摘要

A field experiment was carried out during rainy (kharif) season for 4 consecutive years 2008 to 2012 at Dholi, Bihar to assess the effect of integrated nutrient management on productivity and profitability of pigeonpea [Cajanus cajan (L.) Millsp.] under rainfed condition. Plant height, yield indices, viz. branches/plant, pods/plant, 100-seed weight, leaf area index, fruiting efficiency (15.6%), grain (2.01 tonnes/ha.) and stalk yields, harvest index, protein content, water-use-efficiency (2.9 kg grain/ha/mm), production efficiency (8.3 kg/ha/day), NPK uptake, net returns (67.55 x 10~3 /ha) and benefit: cost ratio (2.9) were significantly higher at recommended dose of fertilizer (RDF) than 50% RDF. Application of farmyard manure (FYM) 5.0 tonnes/ha besides increasing these indices significantly also enhanced nodules number and dry-weight/plant, Rhizobium and phosphate-solubilizing bacteria (PSB) count, phosphorus-solubilizing efficiency and acetylene reduction activity than no FYM. Seed inoculationwith Rhizobium + PSB and Rhizobium + PSB + plant-growth promoting rhizobacteria (PGPR) were found equally effective and significantly enhanced branches/plant and pods/plant, fruiting efficiency, grain and stalk yields, harvest index, production efficiency, NPK uptake, number and dry- weight of nodules/plant, Rhizobium and PSB count, phosphorus-solublizing and acetylene reduction activity, net return and benefit: cost ratio than uninoculated condition. Application of FYM 5.0 tonnes/ha together with 50% RDF resulted in significantly higher grain yield of pigeonpea (2.08 tonnes/ha) than RDF alone (1.90 tonnes/ha). Likewise, seed inoculation with Rhizobium + PSB (1.95 tonnes/ha) and Rhizobium + PSB + PGPR (2.02 tonnes/ha) fertilized with 50% RDF recorded similar grain yield to that of RDF alone (2.01 tonnes/ha). Application of RDF, FYM 5.0 tonnes/ha and seed Inoculation with biofertilizers, Increased organic carbon, available N, P and K contents and reduced the bulk density of the soil over compared withinitial soil value.