Annual legumes as green manure crops

Abstract

There is a large number of annual legume species having an economic importance either on a world or local scale, such as pea (Pisum sativum L.), faba bean (Vicia faba L.), lentil (Lens culinaris Medik.), grass pea (Lathyrus sativus L.) and vetches (Vicia spp.). All these crops are multi-functional and are used for both human consumption and in animal feeding. Apart from these various food and feed uses, annual legumes may represent a quality green manure, playing one of the most significant roles in organic farming and sustainable agriculture. In addition to their ability to increase soil fertility by a symbiosis with nitrogen-fixation bacteria, annual legumes are able to produce a considerable amount of aboveground biomass, also rich in nitrogen. For instance, aboveground biomass nitrogen yield in grass pea may surpass 300 kg ha-1, while in lentil it is higher than 100 kg ha-1.