DOG MUSTARD (ERUCASTRUM-GALLICUM) RESPONSE TO CROP COMPETITION

Greenhouse studies suggested that dog mustard was less competitive tha n wheat, but of similar competitiveness to flax. In field studies, dog mustard growth and development were markedly affected by crop competi tion. Competition from flax and wheat reduced dog mustard leaf area, s hoot dry weight, plant height, and seed production compared with the w eed grown on summer-fallow. Dog mustard was a prolific seed producer w hen grown in the absence of interspecific competition. On summer-fallo w, dog mustard produced as many as 79,100 seeds plant(-1) when moistur e was not a limiting factor. However, average seed production was 19,4 00 and 8000 seeds plant(-1) in 1994 and 1995, respectively.