Nutrient uptake by rice and weeds as influenced by different weed management practices in dry-seeded rice

摘要

Rice cultivation by direct-seeding is viewed as both cost and labor saving practice and becoming popular alternative to transplanting in some regions of Asia. Compared to transplanted rice, under direct-seeding, weeds have been found to be the biggestbiological constraint because they emerge simultaneously with rice seedlings (Rao and Nagamani 2013). Ninty per cent loss in grain yield due to weeds in direct-seeded rice was reported by Zahoor et al. (2014). The yield losses in direct-seeded rice mayrange from 10 to 100% depending on type of weed flora, their density and duration of competition (Rao et al. 2007). In this context, the present investigation was carried out to study the effect of weed management practices on nutrient uptake of weeds and crop.