Symbiotic characters, thermal requirement, growth, yield and economics of pigeonpea (Cajanus cajan) genotypes sown at different dates under Punjab conditions

Abstract

A field experiment was conducted during kharif (rainy season) 2008 and 2009 at research farm of the Punjab Agricultural University, Ludhiana, to study the effect of four/three sowing dates (1 May, 15 May, 1 June and 15 June in 2008 and 15 May, 1 June and 15 June in 2009) on the symbiotic characters, thermal requirement, growth, productivity and economics of four pigeonpea genotypes (AL 201, AL 1507, AL 1578 and AL 1593). Days taken to 50% flowering, physiological maturity, and various agroclimatic indices i.e. AGDD, AHTU, APTU and HUE decreased with delay in sowing. The crop sown on 15 May recorded the highest nodule dry weight plant -1. The grain yield was significantly higher for the 15 May sowing compared to the 15 June sowing. During the two years, the crop sown on 15 May registered on average 6.7 and 48.0 percent higher grain yield than the1 June and 15 June sowings, respectively. The crop sown on 15 May gave the maximum gross returns, net returns and benefit-cost (B:C) ratio. Among the genotypes, AL 1507 recorded the highest nodule number plant-1 and AL 1578 recorded the maximum nodule dry weight plant-1.Genotypes AL 1507, AL 1578 and AL 1593 registered on average 19.4, 19.2 and 20.0 percent higher grain yield relative to AL 201, respectively. The genotype AL 1507 in 2008 and AL 1593 in 2009 performed better in terms of heat use efficiency for grain yield.