Effect of Sowing Dates and Weed Control on Growth and Yield of Broadcasted-seeded Rice (Giza 179 cv)

Abstract

A field study was conducted during 2015 and 2016 seasons in Sakha experimental farm, Kafrelsheikh, Egypt to study the effect of sowing dates and weed control on growth and yield of broadcasted-seeded rice (Giza 179 cv). Three sowing dates viz., May 20 th , May 30 th and June 10 th in individual experiments. Seven weed control treatments i.e., weedy check, Penoxsulam (2.5% OD) at 24 g.ai ha -1 , Bispyribac-sodium (2% SL) at 38 g.ai ha -1 , Fenoxaprop-p-ethyl (7.5% EW) at 63 g.ai ha -1 , Penoxsulam (2.5% OD) plus Azimsulfuron (50% WG) at 14 g.ai ha -1 , Bispyribac-sodium plus Azimsulfuron (50% WG) and Fenoxaprop-pethyl (7.5% EW) plus Azimsulfuron (50% WG), companied analysis was done for the three sowing dates. The results showed that rice sowing on May 20 th reduced the highest number of tillers m -2 and total weeds dry weight while increased dry weight for rice, number of panicles m -2 , panicle weight, number of filled grains panicle -1 and rice grain yield as compared to rice sowing on May 30 th and June 10 th . The application of Penoxsulam (2.5% OD) or Bispyribac-sodium (2% SL) mixed with Azimsulfuron (50 %WG) at recommended doses recorded the lowest number of weed tillers m -2 , total weeds dry weight and highest rice yields as compared to weedy check. The interaction between sowing date and weed control treatment was significant for number of tillers m -2 , total weeds dry weight, rice yield and its components. Sowing date May 20 th with The mixture of Penoxsulam (2.5% OD) or Bispyribac-sodium (2% SL) mixed with Azimsulfuron (50% WG) recorded the lowest total weed characters, highest dry weight, number of panicles m -2 panicle weight, number of filled grain panicle -1 and yield of broadcasted-seeded rice under this study conditions. ai= active ingredient ha. = Hectar