Developing schemes for intercropping annual legumes

Abstract

We established four main principles for mutual intercropping annual legumes: same time of sowing; similar growing habit; similar cutting time; and one component has good standing ability (supporting crop) and another one poor (supported crop). There are three main intercropping groups: (1) ‘tall’ cool season legumes; (2) ‘short’ cool season legumes; (3) warm-season annual forage legumes. In the ‘tall’ cool season group, faba bean and white lupin are supporting crop, while the supported crops are normal-leafed pea common vetch, Hungarian vetch, hairy vetch and grass pea. This may be beneficial for both by weed reduction and preservation of photosynthetically active leaves. The ‘short’ cool season group comprises semi-leafless pea as supporting crop and normal-leafed, bitter vetch and lentil as supported crops. If intercropped, semi-leafless pea provides improved standing ability of the whole intercrop, while normal-leafed pea, bitter vetch or lentil fill the available space within the stand and contribute to better utilisation of sunlight, at the same time reducing weeds. In the warm-season group, soybean and pigeon pea are supporting crops, while mung bean, adzuki bean, black gram, cowpea and hyacinth bean are supported crops. Soybean may bear cowpea or hyacinth bean stems and thus assist in preserving their leaves and profit from significantly decreased weed infestation.