EFFECT OF WEED-CROP COMPETITION ON GROWTH AND YIELD OF GARDEN CRESS

A field experiment to evaluate the effect of weed-crop competition duration i.e. Zero competition and competition for 40, 50, 60, 70 and 80 days after emergence and throughout the growing season on the growth of weeds and yield of Lepidium sativum L. was conducted during 2005-06 at the Agronomic Research Area, University of Agriculture, Faisalabad, Pakistan. The dominant weeds were Phalaris minor, Anagallis arvensis, Chenopodium album, Convolvulus arvensis and Medicago denticulata. Maximum density and dry weight of weeds were recorded in plots with competition throughout the season and the minimum was observed in weed-crop competition for 40 days after emergence. Maximum seed yield was recorded in plots where weeds were not allowed to grow throughout the growing season. The increase in yield was mainly due to greater plant height, branches and seeds per plant. The minimum seed yield was recorded in plots where weeds were allowed to compete with the crop throughout the growth period of the crop. For obtaining higher yield of garden cress it is suggested to control weeds before 40 days after emergence.