Weed Problems, Ecology, and Management Options in Conservation Agriculture: Issues and Perspectives

Abstract

Abstract The unsustainable exploitation of the inelastic resources for farming has led to a widespread degradation of soil resources, which has forced us to rethink our food production strategies into conservation agriculture (CA). It would be difficult to slow down the intensive-production process keeping in view, the demographic pressure. The present-day systems are posing challenges to land, water, and atmosphere, besides the biodiversity. CA involves minimal disturbance of the land, coupled with good agronomic principles such as crop residue management and crop rotation, with the application of chemicals for weed management. With a view to sustainable development in agriculture, CA is a concept trying to reconcile ecology, economy, and performance. Tillage is practiced since ages, for the preparation of field and making weed-free conditions and is an integral component of traditional agricultural systems. However, soil erosion was inevitable. The focal theme of CA revolves around reducing tillage operations. From a weed management point of view, soil tillage brought buried seeds to the upper layer and stimulated their germination and the maintenance of crop residues hampered the herbicide efficacy. However, there are reports of shift in weed population due to the adoption of CA as compared to the conventional agricultural practices posing a formidable challenge to the CA concept. The interaction of weed–crop system becomes too complex. Reduced tillage and zero tillage allowed seed to stay on the surface so that they become prey to the predators. The crop/cover crop residue may also release some chemicals, which may also reduce weed seed germination process. Understanding the weed seed ecology and weed ecology could aid in devising appropriate management options for successful implementation of CA. An integrated management encompassing selection of appropriate crop cultivar and cropping system coupled with CA principles would aid in the management of weeds. Understanding weed seed predation would add value to the management issues. Herbicide resistance need to be given due attention for chemical weed management.