Effect of weed management practices on growth and yield of cassava (Manihot esculenta Crantz)

Abstract

Weed interference is a major constraint to cassava (Manihot esculenta Crantz) productivity, especially during early crop establishment. A three-year field experiment (2020–23) was conducted at the Tapioca and Castor Research Station, Yethapur, Tamil Nadu, to evaluate the efficacy of eight integrated weed management practices under irrigated conditions in a randomised block design (RBD). Treatments included chemical, mechanical, cultural, manual and physical (mulching) approaches. Significant differences were observed among treatments for weed suppression, crop growth, tuber yield, starch content and economic returns. Black polythene mulch (30 µm) consistently achieved the highest weed control efficiency (WCE) (95.8 %), plant height (254.1 cm), tuber yield (37.4 t ha-1) and starch content (29.7 %). This treatment also recorded the highest net return (₹269200 ha-1) and benefit-cost ratio (B : C) (3.56), with tuber yield exceeding that of the unweeded control by more than threefold. Among non-plastic options, intercropping with sunnhemp (Crotalaria juncea L.) combined with mechanical weeding provided effective weed suppression and a high B : C (2.88). The findings demonstrate that integrating physical mulching and cultural-mechanical methods can enhance weed control, increase cassava yield and improve economic sustainability in irrigated tropical production systems.