Residual effect of cluster bean herbicides on succeeding wheat crop

摘要

Cluster bean (Cyamopsis tetragonoloba (L.) Taub.), popularly known as 'Guar', is grown during rainy season in semi-arid and arid regions of India. Cluster bean is grown for different purposes from very ancient time. A seed of cluster bean contains 28-33% gum which is used in almost all types of industries, viz. textiles, paper, petroleum, pharmaceuticals, food processing, cosmetics, mining explosives, oil drilling etc. Cluster bean adds to the fertility of soil by fixing considerable amount of atmospheric nitrogen (Naagar and Meena 2004). As per past 10 years average, guar is being cultivated in India on about 3 million ha with a production of about 1.2 million tons with year to year variation especially in the years of drought as well as on high market demand. Rajasthan contributes 83% to the area and 65% to the production. In 2012, worldwide, about 0.45 million tons of guar products were traded with export value of US$ 4,623 million out of which share of Indian export was 80.8% (0.37 million tonnes) worth US$ 3,916 million. Among all the agricultural export commodities, cluster bean has become the highest foreign exchange earner of 212.87 billions followed by Basmati rice in the recent year of 2012-13 (NRAA 2014).