A PRELIMINARY STUDY OF THE COMPETITION BETWEEN KALE AND THREE WEED SPECIES OF THE GENUS POLYGONUM

摘要

Summary.The results of a pot experiment on the mutual interference between kale and three weed species are reported. The puts were sunk in soil and surrounded by kale plants so as to provide illumination conditions similar to those likely to be found in a field crop of kale. Of the three weed species,Polygonum lapathifoliumappeared to be the most, andP. avicularethe least, competitive towards kale.P. persicariawas slightly less competitive thanP. lapathifolium. The two latter species were much higher in dry‐matter production thanP. aviculareand showed greater responses to changes in the number of kale or weed plants per po