Summer green-manuring crops and zinc fertilization on productivity and economics of basmati rice (Oryza sativa L.)

Field experiments were conducted to study the effects of summer green-manuring crops and zinc (Zn) fertilization on the productivity and economics of Basmati rice. Sesbania aculeata summer green-manuring crop residue incorporation (SGMI) gave highest values of all the growth and yield attributes, grain and straw yield, viz. 3.58, 3.69 t ha(-1) and 16.14, 16.25 t ha(-1) of Basmati rice in 2008 and 2009. Among the Zn fertilization treatments, application of 2.0% Zn-enriched urea (ZEU) as ZnSO4 center dot H2O significantly influenced yield attributes and yield of Basmati rice during both years, and the increase in grain yield was 38.5 and 40.0% over absolute control (no N and no Zn) and 11.9 and 13.6% over control (only N) in both years of study. However, 2.0% ZEU (ZnO) was very close in terms of yield attributes and grain, straw yields of Basmati rice. As regards to the economics of Basmati rice, SGMI and 2.0% ZEU (ZnSO4 center dot H2O) Zn fertilization treatments gave the highest gross (SGMI, 85,985 and 91,582 INR ha(-1); 2.0% ZEU, 89,837 and 59,851 INR ha(-1)) and net (SGMI, 56,997 and 61,445 INR ha(-1); 2.0% ZEU, 59,851 and 64,442 INR ha(-1)) returns, respectively, compared with incorporation of the remaining summer green manuring residue and Zn fertilization treatments in 2008 and 2009. A significantly higher benefit: cost ratio was recorded with SGMI and 2.0% ZEU (ZnSO4 center dot H2O). Overall, Sesbania aculeata green manuring and 2.0% ZEU (ZnSO4 center dot H2O) are excellent sources of N and Zn for improved productivity of Basmati rice.