Residual effect of organic and inorganic sources of nitrogen applied to cotton (Gossypium hirsutum) on succeeding wheat (Triticum aestivum)

The experiment conducted during rainy (kharif) and winter (rabi) seasons of 2001–2002 and 2002–03 under irrigated condition revealed that combined application of 30 kg N and FYM @ 12 tonnes/ha along with Azotobacter (M₄) recorded significantly higher NPK uptake, seed-cotton yield and total dry-matter production of cotton (Gossypium hirsutum L.) compared to individual application of 30 kg N/ha, FYM @ 12 tonnes/ha as well as Azotobacter (M₄ or W₅, but remained at par with 60 kg N/ha alone. Maximum residual effect was observed with combined application of 30 kg N and FYM @ 12 tonnes/ha along with Az. M₄ or W₅ in terms of higher available N, P and K at harvest, that resulted in the marked improvement in the N uptake, yield attributes and yield of succeeding wheat (Triticum aestivum L. emend. Fiori & Paol.) crop. Similarly, higher yield attributes and yield of wheat was recorded with each increment of N up to 120 kg/ha to wheat.