Tripartite Symbiotic System of pea (Pisum sativum L.): Applications in Sustainable Agriculture

The striking increase in the use of nitrogen (N) and phosphorus (P) fertilizers between 1960 and 2000 by intensive agricultural practices has led to degradation of air and water quality (Tilman et al., 2001). However, the existence of common legume plant genes that are implicated in both nitrogen-fixing and arbuscular mycorrhizal symbioses — the two associations that improve mineral nutrition, water supply and tolerance to biotic and abiotic stresses of plants — poses the question of how such a tripartite symbiosis (legume plant + arbuscular mycorrhizal fungi + nodule bacteria) can be exploited in sustainable agriculture (Borisov et al., 2004). The great genetic variability shown in the effectiveness of such a system for pea (and, obviously, for other legumes) clearly demonstrates that we can and should breed legumes to increase the symbiotic potential of the tripartite symbioses (Jacobi et al., 2000).