Sustainable Weed Management in Maize (Zea mays L.) Production: A Review in Perspective of Southern Asia

Weed species and maize crop strongly compete for nutrients, water, space and light for their growth and development. There is a strong correlation between weed population and maize yield. Weeds crop association, critical period of crop-weed competition, methods of weeds control, herbicide tolerant maize cultivars and losses due to weeds and economics of weed control in maize are discussed in this review. The output of different research works clearly indicated that weed infestation led 20-80% reduction in maize yield. The critical period of crop weed competition varies from 2 to 7 weeks after crop sowing, with the most critical competition between 4-7 weeks after sowing. Weed control measures should be taken during this period to minimize the yield loss of maize and increase the water and nutrient use efficiency. Herbicides are popular and widely used measures to control weeds in maize production systems, but several studies have shown their negative environmental consequences. Single approach-based weed management system becomes inefficient against maize weeds. The integrated weed management (IWM) system is recommended to reduce the use of herbicides for its sustainable production.