Development of pea breeding lines with resistance to orobanche crenata derived from pea landraces and wild Pisum spp.

Abstract

Pea (Pisum sativum) is an important grain legume worldwide whose cultivation is severely constrained by the root parasitic weed crenate broomrape (Orobanche crenata), which is widespread in the Mediterranean Basin and Middle East. No resistance is available in commercialized cultivars but some levels of incomplete resistance has been reported in pea landraces and Pisum spp. relatives. In this paper we report the development of a number of advanced pea breeding lines with resistance derived from wide crosses with resistant P. fulvum, P. sativum ssp. elatius, P. sativum ssp. syriacum, and with pea landraces, and critically discuss current progress and future perspectives on pea breeding for broomrape resistance. Resistance of breeding lines was confirmed over five field trials, showing markedly reduced broomrape over ground emergence, and in rhizotron experiments, showing either reduced tubercle formation or, in some of the lines, also hampered tubercle development that might grow slower or even become necrotic and die. Breeding lines performed well agronomically, having similar or mostly higher yields than the parental pea cv. Messire in environments with high broomrape incidence.