Long-term effect, tillage, herbicide, soil properties, weed dynamics

A field experiment was conducted at Jabalpur during winter seasons of 2001-02, 2002-03, 2003- 04 and 2004-05 to study the influence of tillage and herbicides on weed dynamics, yield and soil properties under rice-wheat system in vertisols. Irrespective of the tillage, population of Phalaris minor and Chenopodium album decreased and that of Avena ludoviciana and Medicago hispida increased over time. Zero tillage reduced the population of P. minor and C. album but increased the population of A. ludoviciana as compared to conventional tillage. Application of clodinafop at 0.06 kg/ha fb 2, 4-D ethyl ester at 0.50 kg/ha effectively controlled both grassy and broad-leaved weeds and produced 77.8% higher grain yield than that of isoproturon 1.0 kg + 2,4-D 0.50 kg/ha. Under moisture stress, zero tillage retained more soil moisture than conventional tillage. Tillage and weed control did not affect the physicochemical properties of soil.