GENETIC-RESOURCES OF SALT TOLERANCE IN WILD HORDEUM SPECIES

Salt tolerance was evaluated in 340 accessions of Hordeum, consisting of 41 brittle-rachis forms of Hordeum vulgare L. subsp. vulgare (H. ag riocrithon) accessions, 154 H. vulgare L. subsp. spontaneum (H. sponta neum) accessions, and 145 accessions of ten other species or subspecie s of wild Hordeum. Germination was carried out at concentrations of 17 1, 257, and 342 mM NaCl. The levels of salt tolerance for seed germina tion in wild Hordeum species were generally lower than those found by Mane et al. (1996) in cultivated barley; the NaCl tolerance level of t he different species were as follows: H. agriocrithon > H. spontaneum > other wild Hordeum species. In addition, leaf injury index was used to assess tolerance at the seedling stage after treatment with 500 mM NaCl solution for four weeks. The levels of salt tolerance at the seed ling stage in wild Hordeum species were generally higher than those fo und by Mane & Takeda (1995) in cultivated barley. Most wild Hordeum sp ecies showed high NaCl tolerance at the seedling stage and are conside red good sources of germplasm for salt tolerance breeding.