Role of Allelopathy and Transplanting Space in Reducing Herbicide Use under Transplanted Rice (Oryza sativa L.)

Abstract

Two field experiments were carried out at the farm of Sakha Agric., Res., Station, Kafrelsheikh, Egypt, through 2018 & 2019 seasons to study the role of allelopathy and transplanting space in reducing herbicide use under transplanted rice (Sakha 106 cv). Rice seedlings were manually transplanted under three spaces included 15x20cm, 20x20cm and 25x20cm. Four weed control treatments included pre-mixed herbicide Pindar 13.6% OD (triclopyr-butotyl 12 % + penoxsulam 1.6%) was used at recommended and ½ recommended dose compared with hand weeding and weedy check. Narrow transplanting space recorded the best in controlling E. crus-galli, C. difformis, Eclipta sp., as well as total weeds. Besides, achieved the highest dry weight of rice; panicles m-2; panicle weight and grain yield during both seasons. The highest dry weights of tested weeds and lowest values of rice characteristics were recorded under wider transplanting space throughout the tested seasons. Recommended rate of herbicide exceeded other weed control treatments in weeds control and produced highest dry matter and yield of Sakha 106 cv through both seasons. Recommended or half herbicide rate were the best in controlling weeds; dry weight of rice; grain yield and its attributes under 15 x 20 cm space without significant differences in the two seasons. It could be concluded that allelopathic rice cultivar Sakha 106 can be helpful in reducing herbicide use up to half dose when rice plants were transplanted on 15 x 20 cm.