Sequential application of pre-and post-emergence herbicides to contnmixed weed flora in maize

摘要

Maize (Zea mays L.) is the most versatile food crop of global importance. In India, maize is cultivated in an area of 9.18 million hectares with a production of 24.17 million tonnes and average productivity of 2.63 t/ha. The low yield of maize under Indian conditions is attributed due to a number of factors, among which weeds rank as prime one. Weed infestation in maize was reported to reduce the yield to the extent of 70.27 per cent (Malaviya and Singh 2007). Among the weeds associated with maize, Cyperus rotundus is the dominant weed in Southern Agro-climatic Zone of Andhra Pradesh, India. The recommended pre-emergence herbicides i.e. atrazine is less effective against certain weeds associated with maize especially, Cyperus rotundus. Hence, the present investigation was undertaken to determine the bioefficacy of sequential application of herbicides either alone or in combination to suppress the weed growth in rainy season maize.