CROP BREEDING, GENETICS & CYTOLOGY Genetics of Winter Hardiness in 10 Lentil Recombinant Inbred Line Populations

use of available moisture and by avoiding heat stress. Fall planting is desirable because drier soil conditions Available winter hardy lentil (Lens culinaris Medik.) germplasm allow for planting the crop without the excessive soil has prompted interest in the development and use of cultivars that compaction that is common with spring planting in cold can be fall planted in cold highland areas. This change in production of lentil from normally spring sown to fall sown is environmentally wet soils. Spring planted lentil crops often experience sound and increases yield potential. Understanding the mode of inheriheat stress and terminal drought in the latter part of tance of winter hardiness in lentil would assist breeding efforts. The the growing season that reduces yields. Crops planted objectives of this study were to determine the inheritance and heritain the fall may develop and mature sufficiently early to bility of winter hardiness in lentil. Ten F6 derived recombinant inbred avoid the most severe heat and drought stresses. line (RIL) populations from crosses of winter hardy germplasm lines In cold highland areas, winter lentils are not grown with nonhardy germplasm were planted in a randomized complete because cultivars with sufficient winter hardiness and block design with three replications at Haymana, and Sivas, Turkey, acceptable quality traits are not available. Much of the and at Pullman, WA, USA, between 1997 and 2001. Meaningful data work on lentil winter hardiness has been related to agrofor an analysis of the inheritance of winter hardiness were available nomic, physiologic, and germplasm screening (Kusmenonly at Haymana in 1997-1998 and at Pullman in 1998-1999, indicating oglu and Aydin, 1995; Eyupoglu et al., 1995; Summerinfrequent occurrences of sufficiently cold winters to provide differenfield et al., 1985; Erskine et al., 1981). On the basis of tial killing. Percent survival was calculated on the basis of plant stand available germplasm, however, it should be possible to counts recorded after establishment in the fall and regrowth in the spring. Parental line WA8649041 was the most winter hardy followed develop lentil cultivars with improved winter hardiness by WA8649090, ILL-1878, and ILL-669. General combining ability and acceptable quality (Erskine et al., 1981; Spaeth and (GCA) and specific combining ability (SCA) effects were significant Muehlbauer, 1991). at both locations. Heritability estimates among the 10 RIL populations Genetic studies of winter hardiness in lentil are limranged from 15.9 to 90.7%. Inheritance patterns of winterhardiness ited. A recent study (Ali and Johnson, 2000) indicated appeared to be quantitative on the basis of frequency distributions that winter hardiness had low to moderate heritability and the lack of discrete segregation classes. Since winter hardiness (32–71%). Genetic studies of winter hardiness in other in lentil appears to be a quantitative trait, accumulation of genes food legumes have been investigated in more detail. responsible for winter survival will probably require stringent field Winter hardiness in pea (Pisum sativum L.) is controlled testing or marker assisted selection. by dominant (Cousin et al., 1985) and additive genes (Auld et al., 1983) and by as many as three or four genes (Liesenfeld et al., 1986). Cold tolerance in chickL is an annual self-pollinated diploid (2x 2n pea (Cicer arietinum L.) is controlled by at least five 14 chromosomes) species, and a highly valued food genes with tolerance dominant over susceptibility (Mallegume grown extensively in the Middle East, North hotra and Singh, 1990). Africa, North America, Australia, and South Asia. In Breeding for winter hardiness is considered a longthe Palouse region of the U.S. Pacific Northwest, the term objective because field tests required for differencrop is usually sown in early spring and harvested in tial killing of segregating material are unpredictable and late July or early August. However, winter hardy germinfrequent, occurring perhaps only once every 8 to 10 plasm is available and may be used to develop higher yr (Lewitt, 1980). Winter hardiness is affected not only yielding types that can be planted in the fall. With fall by tolerance to cold but by tolerance to factors such as or early winter planting, lentil yields can be increased frost heaving, water logging, freeze–thaw cycles, and up to 50% (Sakar et al., 1988) by making more efficient diseases as well (Steponkus, 1978). Cultural practices including planting date, plant density, and depth of A. Kahraman, Harran Universitesi Ziraat Fakultesi Tarla Bitkileri planting, also affect winter survival (Kusmenoglu and Bolumu, Sanliurfa, Turkey 63040; I. Kusmenoglu, Ihracatci Birlikleri Aydin, 1995). However, among all these factors, cold Tohumculuk ve Arastirma San. Ve Tic. A.S. Ergazi Mah. Koyici temperature tolerance is the major component of winter Serpmeleri No. 4 Batikent/Ankara, Turkey; N. Aydin, A. Aydogan, hardiness. Selection for winter hardiness on the basis Ankara Tarla Bitkileri Merkezi Arastirma Ens. Mud. PK 226 Ulus, of artificial cold tolerance tests can be considered an Ankara, Turkey; W. Erskine, ICARDA, International Center for Agricultural Research in the Dry Areas, P.O. Box 5466, Aleppo, indirect selection criterion. However, associations beSyria; F.J. Muehlbauer, U.S. Department of Agriculture, Agricultural tween winter hardiness and cold tolerance are not stable Research Service, and the Department of Crop and Soil Sciences, and vary among experiments, perhaps because of exper303W Johnson Hall, Washington State University, Pullman, Washingimental design and artificial conditions (Gullord et al., ton 99164-6434 USA. Received 15 Oct. 2002. *Corresponding author