Assessing weed competitive abilities of rice genotypes in direct-seeded rice using purple rice as model weed Bansal Tanu1, Dhillon Buta Singh2,*, Kumar Virender3, Sagwal Pardeep4, Bhatia Dharminder2 1Department of Agronomy, Punjab Agricultural University, Ludhiana, Punjab, India 2Department of Plant Breeding & Genetics, Punjab Agricultural University, Ludhiana, Punjab, India 3International Rice Research Institute (IRRI), Los Banos, Laguna, Philippines 4International Rice Research Institute, South Asia Regional Centre, Varanasi, India *Corresponding author email: bsdhillon@pau.edu
Online Published on 24 April, 2024. Abstract Studies were undertaken to evaluate the influence of crop-weed competition period and genotypes on crop emergence, vigour, growth, yield attributes, yield and weed growth in direct-seeded rice during rainy season (Kharif) 2020 at Punjab Agricultural University, Ludhiana, India. The experiment comprising four crop-weed competition period viz; Weedy throughout (WT), Weed free up to 15 days (WF15), Weed free up to 30 days (WF30) and weed free throughout (WF-Th) in main plots; and eight genotypes (RYT 4004, RYT 4005, RYT 4079, RYT 4080, RYT 4081, PR 120, PR 126 and SAVA 134) in sub-plots with 3 replications was laid out in split plot design. The competition to the crop was imposed through purple rice. It is evident that keeping the crop weed free up to 30 days recorded crop emergence, vigour, yield attributes and yield similar to that of weed free throughout treatment. Among genotypes, SAVA 134, PR 120 and PR 126 were found to be weed suppressive and high yielding genotypes. Although RYT 4081 was also weed suppressive but gave the least grain yield. Among various traits, grain yield (-1.5437) exerted very high negative direct effect fb leaf area index (LAI) at 7 DAS (-0.9185) fb plant tillers at physiological maturity (-0.8908) on DMA by surrogate weed at physiological maturity. All the parameters namely; root length (7 DAS), plant height (30 DAS), plant tillers (60, 90 DAS and physiological maturity), flag leaf area, number of leaves/plant (60 DAS), DMA (30 DAS), dry matter partitioning to panicles (at anthesis), panicles/m22and straw yield exerted high negative indirect effect through grain yield as well as LAI (7 DAS) on surrogate weed DMA at physiological maturity. Top Keywords Crop-weed competition period, Flag leaf area (FLA), Genotypes, Physiological maturity (PM), Purple rice. Top |