Vol. 17 No. 2
Influence of weed management practices on weed flora, crop yield and nutrient uptake in direct seeded rainfed lowland rice
Author(s): M. S. S. K. REDDY AND M. AMEENA
Abstract: An investigation was conducted at IFSRS, Karamana, Thiruvananthapuram during kharif 2019 to study the influence of weed management options on crop nutrient uptake and weed nutrient removal in direct seeded rainfed lowland rice. The investigation was conducted in randomized block design with eight treatments comprising of application of pre, early-post and post-emergent herbicides followed by (fb) hand weeding (HW) along with two controls (weed-free check and unweeded control) evaluated in three replications. Amongst the weed management options tested, the least weed dry weight during the critical growth stages and nutrient removal was recorded by penoxsulam+cyhalofop butyl 6% OD at 150 g ha-1 at 20 days after sowing (DAS) fb HW at 40DAS and at par with bensulfuronmethyl+pretilachlor @ 60+600 g ha-1 at 3DAS fb HW at 40DAS. Use of bensulfuronmethyl+pretilachlor @60+600 g ha-1 at 3 DAS fb HW at 40DAS maintained higher weed control efficiency allthrough the growth period and the NPK removal by weeds was limited to only one tenth of that registered in unweeded control. The ready-mix herbicides bensulfuronmethyl+pretilachlor (at 3 DAS) and penoxsulam+cyhalofop butyl (at 20DAS) each fb HW at 40DAS provided a minimal weed presence at the critical period and resulted in superior grain yields (5461and 5355 kg ha-1, respectively), dry matter production (13.17 and 13t ha-1,respectively,) crop NPK uptake and weed NPK removal in direct seeded rainfed lowland rice.
Download Full Article: Click Here