Weed seed bank studies under different cropping systems of Indo-Gangetic plains

Abstract

Weed infestations are the major constraints and its control is a major hurdle in conservation agriculture (CA) based systems since weed ecology and management are entirely different in CA systems. Weeds pose serious threat to the companion crop through its competition for nutrients, water, sunlight and space, which cause considerable reduction in yield. The sources of these huge economic losses and weed infestations in crops is primarily due to weed seed bank (WSB) which describes the reservoir of viable weed seeds or fruits found in soil or at its surface. To deplete the weed seed bank, weed seed􀀐set should be avoided by all means and needs to be addressed in a holistic way. Keeping in view the above facts, the present investigation was undertaken to study the “weed seed bank studies under different cropping systems of indo-gangetic plains” at ICAR-Indian Institute of Maize Research, Ludhiana, Punjab. During the course of study it was observed that lower weed density (No./8 kg soil) of 88.67 and 118.33 was observed in Rice-Wheat-Moong system (conventional agriculture) at both 0-5 cm and 5-15 cm soil depths. At 5-15 cm soil depths, Maize-Wheat-Moong in both the systems (conventional and conservation agriculture) recorded more number of weeds than Rice-Wheat-Moong system (conventional agriculture). Weed density (No./8 kg soil) was highest at 0-5 cm soil depth in conservation agriculture than 0-5 cm in conventional agriculture. Highest total and average weed density (No./8 kg soil) of 508.33, 254.16 was observed in Maize-Wheat-Moong system (conservation agriculture) followed by 433.33, 216.66 and 207, 103.5 in Maize-Wheat-Moong system (conventional agriculture) and Rice-Wheat-Moong system (conventional agriculture) respectively. Therefore it can be concluded that weed seeds and weed growth is highest in conservation agriculture than conventional agriculture and needs more focus for weed management for increasing productivity and profitability of cropping systems in Indo-Gangetic plains of India.