1Mountain Research Centre for Field Crops, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Khudwani Campus, J&K-192102, India
2RARS-Rajouri, Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu, Main Campus, Chatha, J&K-180009, India
*Corresponding author: dr.narinderpanotra@gmail.com
Online published on 7 May, 2018.
Field experiment was conducted at Mountain Research Centre for Field Crops, SKUAST-Kashmir, Khudwani during Kharif 2012 and 2013 on slity clay loam soils. The soil of the experimental field was neutral in reaction, testing medium in available P, K and organic carbon content and low in available N. The treatments comprising of three irrigation schedules: alternate wetting and drying (AWD), saturation conditions and continuous flooding and seven weed management practices including four herbicidal treatments (pyrazosulfuron ethyl @ 20 ga.i./ha(3 DAT); cyhalofop butyl @ 80 ga.i.,/ha(15 DAT); pyrazosulfuron ethyl 20 ga.i. fb cyhalofop butyl 80 g a.i.,/ha(3 and 15 DAT); butachlor @ 1.5 kga.i./ha(3 DAT); three Cono weedings (15, 25 and 35 DAT); along with control and weed free treatment replicated thrice were tested in split plot design to ascertain the most effective herbicide for the control of weeds in rice (Oryza sativa L.) under SRI. The data revealed that significant increase in dry matter accumulation by the crop and grain yield was recorded due to the saturation water regime, which was superior to AWD and continuous flooding during both the years of experimentation. However, continuous flooding recorded lower weed densities, dry matter and weed control efficiency. Higher weed index was recorded with saturation water regime. The data on weed management practices revealed that among the herbicides tested, sequential application of pyrazosulfuron-ethyl @ 20 g a.i./ha(3 DAT) fb cyhalofop-butyl @ 80 g a.i./ha(15 DAT) produced significantly higher grain yield and dry matter accumulation by the crop comparable to other weed management measures and weedy check treatment. The same treatment also recorded lower weed densities, weed dry matter and weed index but recorded higher weed control efficiency over other weed management practices and control during both the years.
Pyrazosulfuron-ethyl @ 20 ga.i./ha fb cyhalofop-butyl @ 60 ga.i./ha in saturation water regime may be recommended for effective and economical weed management, as the combination proved to be instrumental in enhancing yield and weed control efficiency in the System of Rice Intensification.
Water regimes, weed density, weed control efficiency, weed index, SRI
