Growth and phenology of eight common weed species

The relative growth rate (RGR), resource allocation and phenological behaviour were determined for eight common weed species growing in the field crops of Beni-Suef governorate, Egypt. The RGR decreases with age. The increased RGR together with high dry matter investment into vegetative parts during seedling and juvenile stages, promote the competitive ability required for the weedy species. The investigated species mostly exhibit a decrease in dry matter allocation to roots with age. Most of the studied species invest relatively large proportions of phytomass into the reproductive parts. The phenological pattern of the weedy species seems to be affected by the sowing time of the crop and the crop longevity in addition to differences in light conditions resulting from differences in the cropping systems.