Author(s):

Santosh Kumar Dubey, Arun Kumar, Mahendra Singh, Ashok Kumar Singh, Shashank Tyagi and Vinod Kumar

Abstract: The use of herbicides in direct-seeded rice may affect the biological equilibrium of the soil and thus influence the nutrient status, health and productivity of the soil. To study the effect of herbicides on soil microbial population of direct-seeded rice, a field experiment was conducted with fourteen treatments at Agriculture Research Farm, Bihar Agricultural University, Sabour, Bhagalpur, Bihar, India during Kharif 2016 and 2017. The results revealed that viable microbial population was influenced to varying degrees with different weed control treatments during both the years. The application of treatment (T₉) Bispyribac-Na 30 g <em>a.i.</em> ha^-1PoE, significantly increased by 121.71% and 134.08% actinomycetes population when compared with the treatment weed free and weedy check, respectively at 90 days after sowing. Similarly, the application of herbicides treatment (T₁) Pendimethalin 1000 g.a.i ha^-1 (PE) also significantly increased actinomycetes count by 74.59% and 91.33% when compared with the treatment weed free and weedy check, respectively at 90 days after sowing. Application of treatment (T₁₀) Bispyribac-Na 15 g <em>a.i.</em> ha^-1<em>fb </em>one hand weeding at 40 days statistically influenced the grain and straw yields and harvest index over all othertreatments. Highest grain (66.67 q ha^-1) and straw (97.77 q ha^-1) yields and harvest index (40.54%) was observed under (T₁₀) Bispyribac-Na 15 g <em>a.i.</em> ha^-1<em>fb </em>one hand weeding at 40 daysand was statistically at par with Azimsulfuron 17.5 g <em>a.i.</em> ha^-1<em>fb</em> one hand weeding at 40 days after sowing (T₁₂). The herbicides, viz. Pendimethalinand Pyrazosulfuronas pre-emergence and Almix, Ethoxysulfuron, Bispyribac-Naand Azimsulfuron as post-emergence were safe for soil microbial populations at recommended rate.

Pages: 83-87  |  1645 Views  572 Downloads

Download (446KB)