Ecology, Environment and Conservation Paper

GROWTH AND PRODUCTIVITY OF DIRECT SEEDED RICE AS INFLUENCED BY SEED RATES AND TIMING OF KNOCKDOWN OF DHAINCHA IN RICE-MAIZE SEQUENCE

Botha Prashanthi, P.V.N. Prasad, K. Srinivasulu, P. Venkata Subbaiah and S. Ratna Kumari

Abstract

A field experiment was conducted during the kharif seasons of 2020-21 and 2021-22 to evaluate the effect of seed rates and timing of knockdown of dhaincha on growth and productivity of direct seeded rice. The experiment was laid out in split-plot design. The main plot treatments consisted of brown manure species of Dhaincha (Sesbania aculeata) sown at three seed rates (20, 30 and 40 kg ha-1) and sub plot treatments comprising knockdown of dhaincha at four stages (20, 25, 30 and 35 DAS) using 2,4-D @ 0.5 kg ha-1 with three replications. Dhaincha seed rate @ 40 kg ha-1recorded significantly taller plants, higher number of tillers m-2, number of panicles m-2, test weight and grain yield and among the timing of knockdown days of dhaincha the highest values were observed with treatment of brown manuring at 30 DAS. However, BM at 25 DAS maintained parity with BM at 35 DAS treatment. Thus, brown manuring practice with dhaincha seed rate @ 40 kg ha-1 and knocking it down at 30 days has displayed profound effectiveness in realizing higher grain yield of direct seeded rice in rice-maize system.