Critical period of crop-weed competition in sugarcane ratoon

摘要

Ratooning is an integral part of sugarcane cultivation. It occupies almost 50 percent of total sugarcane acreage, however, productivity of ratoon is only 45 t ha~(-1) against the plant crop productivity of 791 ha~(-1). Negligent attitude of farmerstowards ratoon in general and its heavy infestation with weeds in particular is the main reason for poor productivity of ratoon in India. The ratoon crop faces tough competition with weeds during establishment stage of the crop, which results in 30 to 45percent loss in cane yield. In order to minimize the loss in yield due to weeds, their efficient management is imperative. To achieve this, the information about most critical period of crop-weed competition is required as presence of weeds during thisperiod inflicts maximum loss to the crop yield and it is the shortest span of time in the ontogeny of crop growth when weeding results in higher economic returns (Bhan and Mishra, 1993). Information on the critical period of crop-weed competition in plant cane is available in plenty; however, as far as ratoon is concerned only meager information is available. Since nature of weed problem is different in ratoon the present work was carried out to delineate the critical period of cropweed competition.