Studies on Weed Control : Part 1. Rotation system and weed control

[摘要] To elucidate the effects of crop rotation upon weed control, observations were made of occurrence of weeds in thirty one experimental plots of field, twenty-six of those being under rotation and the others under continuous cropping. The dominant species of weeds accompanying a crop were found to vary according to the kind of the crop, and were affected by its cultivation practices, e.g. seeding time of the crop, culture management, etc. or also by the growth habit of the crop. On the continuous cropping fields, the characteristic effects of the crop upon weeds were found remarkably cumulative, while on the rotation fields, the diversity of weed species changed according to the cropping system. Among the cropping systems examined in this study, the three year rotation with a course of "potato-wheat-Chinese cabbage-corn" and the two-year rotation with "potato-wheat-buckwheat" were found to bring about comparatively sparse occurrence of weeds ; on the other hand, the three-year rotation with "potato-rape-green fodder soybean-wheat-seed soybean", the two-ear rotation with "barnyard millet-wheat-soybean" and the two-year rotation with "potato-wheat-soybean" generally tended to court heavier infestation with weeds.

[学科分类] 农业科学（综合）