Soil Incorporated Plant Residues and Nemacur affected Weed Population and Soil Nitrogen Dynamics in Asclepia Field

Abstract

Field trials were conducted for two seasons in 2006 and 2007 to test the effect of Tagetes patula, Lantana camara, Tephrosia vogelii, Azadirachta indica and Nemacur on the growth of asclepiad, soil pH, and soil nitrogen as well as weed population dynamics. The experiment was replicated three times under complete randomized block design. Chopped plant materials were applied singly or in combination with nemacur. T. patula was applied at 300 g/m2 , A. indica at 150 g/m2 , L. camara at 10% w/w, and T. vogelii at 10% w/w. Organic plant materials were applied at half rate in combination with nemacur at 20 g/m2 . Nemacur treatment alone was applied at a full rate of 40 g/m2 . Tagetes patula with nemacur reduced weed biomass between 33.6% and 36.6% while L. camara alone decreased the population density of Oxalis cornulata weed between 14% and 17% compared to the untreated control. The improvement of nutrient status of the soil and the control of weeds could have led to an improvement of yield characteristic of asclepias. A combination of L. camara with nemacur may be used instead of synthetic nematicides alone to control weeds and improve soil nutrient levels.