CR 17-1-34, Cercospora Leaf Spot Resistant Southernpea Germplasm1

Abstract Cercospora leaf spot, a disease incited by Cercospora cruenta Sacc., is one of the major foliage diseases of southernpeas ( Vigna unguiculata (L.) Walp.) in several important U.S. production areas3. The disease is frequently a problem on fall crops where severe losses are occasionally observed. Cercospora leaf spot spreads very rapidly on susceptible cultivars, resulting in premature defoliation and reduced yields. Schneider4 reported that C. cruenta caused yield reductions of 42% in Nigeria. Accessions of V. unguiculata resistant to C. cruenta have been reported by Verma and Patel (3) and Vakin4. Schneider (3) used resistant cultivars in his work. The lack of information about the inheritance of resistance and the agronomic or exotic nature of many of these lines limit their value as sources of Cercospora leaf spot resistances in horticultural breeding programs. The breeding line CR 17-1-34 has been released for use as a resistant parent in such programs. It is a horticultural type that carries one of the genes reported by Fery et al. (2) to condition a high level of resistance to Cercospora leaf spot.