Microsatellites have currently become the markers of choice for molecular mapping and marker-assisted selection for key traits such as disease resistance in many crop species. We report here on the mapping of microsatellites which had been identified from a genomic library of lentil (Lens culinaris Medik.). The majority of microsatellite-bearing clones contained imperfect di-nucleotide repeats. A total of 41 microsatellite and 45 amplified fragment length polymorphism (AFLP) markers were mapped on 86 recombinant inbred lines derived from the cross ILL 5588 x L 692-16-1(s), which had been previously used for the construction of a random amplified polymorphic DNA and AFLP linkage map. Since ILL 5588 was resistant to fusarium vascular wilt caused by the fungus Fusarium oxysporum Shlecht. Emend. Snyder & Hansen f.sp. lentis Vasud. & Srini., the recombinant inbreds were segregating for this character. The resulting map contained 283 markers covering about 751 cM, with an average marker distance of 2.6 cM. The fusarium vascular wilt resistance was localized on linkage group 6, and this resistance gene was flanked by microsatellite marker SSR59-2B and AFLP marker p17m30710 at distances of 8.0 cM and 3.5 cM, respectively. These markers are the most closely linked ones known to date for this agronomically important Fw gene. Using the information obtained in this investigation, the development and mapping of microsatellite markers in the existing map of lentil could be substantially increased, thereby providing the possibility for the future localization of various loci of agronomic interest.

The adaptability and productivity of cool-season food legumes (chickpea, faba bean, lentil, pea) are limited by major abiotic stresses including drought, heat, frost, chilling, waterlogging, salinity and mineral toxicities. The severity of these stresses is unpredictable in field experiments, so field trials are increasingly supplemented with controlledenvironment testing and physiological screening. For drought testing, irrigation is used in dry fields and rain-out shelters in damp ones. Carbon isotope discrimination ( 13 C) is a well-established screen for drought tolerance in C3 cereal crops which is now being validated for use in grain legumes, but it is relatively expensive per sample and more economical methods include stomatal conductance and canopy temperature. Chickpea lines ICC4958 and FLIP87-59C and faba bean line ILB938 have demonstrated good drought tolerance parameters in different experiments. For frost tolerance, an efficient controlled-environment procedure involves exposing hardened pot-grown plants to subzero temperatures. Faba beans Cote d'Or and BPL4628 as well as lentil ILL5865 have demonstrated good freezing tolerance in such tests. Chilling-tolerance tests are more commonly conducted in the field and lentil line ILL1878 as well as derivatives of interspecific crosses between chickpea and its wild relatives have repeatedly shown good results. The timing of chilling is particularly important as temperatures which are not lethal to the plant can greatly disrupt fertilization of flowers. Salinity response can be determined using hydroponic methods with a sand or gravel substrate and rapid, efficient scoring is based on leaf symptoms. Many lines of chickpea, faba bean and lentil have shown good salinity tolerance in a single article but none has become a benchmark. Waterlogging tolerance can be evaluated using paired hydroponic systems, one oxygenated and the other de-oxygenated. The development of lysigenous cavities or aerenchyma in roots, common in warm-season legumes, is reported in pea and lentil but is not well established in chickpea or faba bean. Many stresses are associated with oxidative damage leading to changes in chlorophyll fluorescence, membrane stability and peroxidase levels. An additional factor relevant to the legumes is the response of the symbiotic nitrogen-fixing bacteria to the stress.

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Micronutrient malnutrition, the hidden hunger, affects more than 40% of the world's population, and a majority of them are in South and South East Asia and Africa. This study was carried out to determine the potential for iron (Fe) and zinc (Zn) biofortification of lentils ( Lens culinaris Medikus subsp. culinaris ) to improve human nutrition. Lentils are a common and quick-cooking nutritious staple pulse in many developing countries. We analyzed the total Fe and Zn concentrations of 19 lentil genotypes grown at eight locations for 2 years in Saskatchewan, Canada. It was observed that some genetic variation exists for Fe and Zn concentrations among the lentil lines tested. The total Fe and Zn concentrations ranged from 73 to 90 mg of Fe kg(-1) and from 44 to 54 mg of Zn kg(-1). The calculated percentages of the recommended daily allowance (RDA) for Fe and Zn were within the RDA ranges from a 100 g serving of dry lentils. Broad-sense heritability estimates for Fe and Zn concentrations in lentil seed were 64 and 68%, respectively. It was concluded that lentils have great potential as a whole food source of Fe and Zn for people affected by these nutrient deficiencies. This is the first report on the genetic basis for Fe and Zn micronutrient content in lentils. These results provide some understanding of the genetic basis of Fe and Zn concentrations and will allow for the development of potential strategies for genetic biofortification.

Lentil anthracnose (Colletotrichum truncatum (Schwein.) Andrus et W.D. Moore is a potential threat in many lentil (Lens culinaris Medik.) production regions of North America. In the lentil germplasm maintained in Germany and North America, 16 lines were reported to have resistance to race Ct1, but none has resistance reported to race Ct0. The objective of this study was to examine accessions of wild Lens species for their resistance to races Ct1 and Ct0 of lentil anthracnose. Five hundred and seventy-four wild accessions of six species and control lines were screened in two replications under both field and greenhouse conditions using a 1-9 scoring scale (1, highly resistant; 2-3, resistant; 4-5, moderately resistant; 6-7, susceptible; and 8-9, highly susceptible). Indianhead and PI 320937 were resistant while Eston and Pardina were susceptible to race Ct1 as expected. However, none of the check lines were resistant to race Ct0. Among the six Lens wild species tested, accessions of Lens ervoides (Brign.) Grande had the highest level of resistance, 3-5 to race Ct1 and Ct0 followed by L. lamottei Czefr. in the field and greenhouse. Lens orientalis (Boiss.), L. odemensis L., L. nigricans (M. Bieb.) Godron and L. tomentosus L. were highly susceptible, 8-9 to race Ct0 in the greenhouse. The highest frequency of resistance, especially in L. ervoides (Brign.) Grande, was found in accessions originating from Syria and Turkey. The usefulness of these L. ervoides (Brign.) Grande accessions as sources of resistance to the more virulent race of anthracnose in a lentil breeding program is discussed.