Salt tolerance polymorfism in seadlings of wheat-wheat grass hybrids

Wheat is a glycophyte that cannot grow under saline conditions. One of the approaches to increase efficiency of land suffering from high salinity is to develop salt tolerant cultivars. This implies the search for gene donors among wild relatives of wheat including wheatgrass (Thinopyrum). Salt tolerance of ten lines of wheat-wheatgrass hybrids were estimated by measuring root and leaf growth rate on the 3d and 7th day of germination in control (water) and sodium chloride solution (100, 150 or 200 мM). As a result, the lines with stable high, medium and low growth depression have been revealed as well as the lines with varying response to salinity depending on salt concentration, day of estimation or organ. Genetic distances between the investigated lines were measured using PCR-markers iPBS, RAPD and ISSR. The clusters formed according to the experimental results are as follows: 2087 and М-3202 (stable high tolerance of root); 2087, 4082 and 548 (stable medium tolerance of leaf); 4082 and М-12 (stable low tolerance of root; different genetic systems conferring similar salt stress response of leaf or root might be assumed); ZP-26 and 4044 (tolerance varies from low to high; the lines are supposed to have similar mechanisms of salt tolerance and gene controlling them).