CROP WILD RELATIVES

The current global climate change results in shift and shrinkage of ranges of crop cultivation. The potential of crop wild relatives as an important source of genetic diversity for breeding is underestimated. Wild relatives of pea include the species P. fulvum and the subspecies P. sativum subsp. elatius, whereas wild representatives of P. abyssinicum are unknown. Wild peas are characterized by spontaneous dehiscence of pods and ballistic seed dispersal. The cultivated pea represents just a phyletic lineage within P. sativum. Pea crop wild relatives are promising with respect to: (1) resistance to pests and pathogens; (2) resistance to abiotic stress; (3) nutritional value; (4) agrotechnical advantages, e.g. branching, ability of hibernation etc.; (5) symbiotic nitrogen fixation; etc. P. fulvum is resistant to pea weevil, rust, powdery mildew and ascochyta blight. Some P. sativum subsp. elatius are resistant to nematodes, broomrape, powdery mildew, Fusarium wilt, root rot, ascochyta blight and white wilt. P. sativum subsp. elatius responds to weevil oviposition by neoplastic pustules of the pod wall controlled by the locus Np. Some P. sativum subsp. elatius accessions have lowered transpiration rates, and an accession from Italy survives at–20°C. Analyses of quantitative trait loci have been carried out for resistance of P. fulvum to pea weevil, powdery mildew and rust and for resistance of P. sativum subsp. elatius to broomrape, bacterial blight and ascochyta blight. Aryamanesh et al. (2012) obtained five introgression lines with pea weevil resistance transferred from P. fulvum to P. sativum. The practical use of wild peas is hampered by insufficient awareness of their diversity and differences from cultivated peas. Studies of useful traits of wild peas and their natural diversity, which is rapidly vanishing, should be intensified.