Identification of pea accessions with combined resistance to Fusarium wilt and drought

Abstract

Pea, Pisum sativum L. is one of the major legume crops worldwide. However, its yield remains relatively low mainly due to its high susceptibility to stresses. Pea is particularly susceptible to drought and to Fusarium wilt caused by the soilborne fungal pathogen Fusarium oxysporum, whose damage is favored by by warm temperatures and dry weather. Loses caused by this pathogens are thus expected to be more severe and widespread in future due to climate changes that also predicted an increase of drought prone areas. The use of resistant cultivars is currently the most efficient control approach. However, the existing resistance level introduced in legume cultivar is still insufficient to control the disease. It is thus crucial to identify and exploit new sources of resistance to F. oxysporum and drought. In the frame of the EU project, ABSTRESS, we initially established an optimum inoculation method suitable to study legume response to fusarium wilt and its interaction with drought stress using the model legume Medicago truncatula. This methodology was then applied to screen a large Pisum collection to identify pea accessions resistant to F. oxysporum. Twenty pea accessions were found highly resistant to F. oxysporum. The response of these resistant sources to combined fusarium wilt and drought stresses were then tested under controlled condition allowing identification of several accessions with high level of resistance to fusarium wilt and tolerant to drought. These sources of resistance would be very valuable to introgress resistance to both stresses in pea cultivar.