Influence of Sowing Time and Weed Management Practices on the Performance and Weed Dynamics of Direct Drum Seeded Rice

Direct drum seeding has emerged as a viable and alternatesubstituteto the current transplanted rice to address constraints of labor andwater scarcity as well as rising cultivation costs. However, heavyweed infestation is the main biological factor leading to immenseyield loss, which requires immediate attention. Therefore, adoptionof efficient weed management practice is critical for the successand widespread adoption of direct seeded rice. In this regard, anexperiment was laid out at the Faculty of Agriculture, Wadura, SKUASTof Kashmir, India, in Kharif seasons of 2018 and 2019 to assess theefficiency of direct seeded rice (DSR) under two sowing dates (D-1: 10th May and D-2: 3rd June) and six weed managementstrategies (W-1: weedy check (untreated check), W-2: four mechanized conoweedings at 15, 30, 45, and 60 DAS (days aftersowing), equivalent to weed free (four conoweedings, equivalent toweed free), W-3: bensulfuron-methyl + pretilachlor @ 60and 600 g a.i. ha(-1) as pre-emergence (BSM + pretilachlor,PE), W-4: oxyfluorfen @ 750 g a.i. ha(-1) as pre-emergence (oxyfluorfen, PE), W-5: bensulfuron-methyl+ pretilachlor @ 60 and 600 g a.i. ha(-1) as pre-emergencefollowed by 2,4-D @ 0.75 kg a.i. ha(-1) as post-emergence(30-35 DAS) (BSM + pretilachlor PE fb 2,4-DPoE), and W-6: oxyfluorfen @ 750 g a.i. ha(-1) as pre-emergence followed by 2,4-D @ 0.75 kg a.i. ha(-1) as post-emergence (30-35 DAS) (oxyfluorfen PE fb 2,4-D PoE) on growth characteristics, productivity, weed infestation,and nutrient dynamics. The pooled results showed that 10th May sowingrecorded significantly higher values of growth characteristics viz.plant height, dry matter production, tiller count, and yield characteristics,including panicle weight, panicle length, filled grains per panicle,and test weight, as compared to delayed sowing (3rd June). Earliersowing (10th May) produced significantly higher grain yield (7.33t ha(-1)) and straw yield (8.99 t ha(-1)) when compared to the delayed sowing (3rd June) which produced agrain yield of 6.08 t ha(-1) and straw yield of 7.93t ha(-1). Among weed management strategies, four mechanizedconoweeding at 15, 30, 45, and 60 DAS resulted in enhanced growth,yield characteristics, and yield but was statistically similar tobensulfuron-methyl (BSM) + pretilachlor PE fb 2,4-Dpost-emergence (PoE). Delayed sowing (3rd June; D-2) recordedsignificantly higher weed density and dry-weed biomass as comparedto earlier sowing (10th May; D-1). Among the herbicidestested, sequential application of BSM + pretilachlor PE fb 2,4-D PoE proved an efficient weed management practice with a significantlyreduced population and dry weight of weeds. Therefore, it was concludedthat 10th May sowing with four mechanized conoweedings or sequentialapplication of BSM + pretilachlor PE fb 2,4-D PoEis promising for improving productivity and efficient weed controlin direct drum seeded rice under temperate Kashmir conditions.