Frost Tolerance in Winter Wheat Germplasm of Diverse Origin in Central Asia.

Wheat production is directly linked to food security in Central Asia. There are several abiotic constraints to successful winter wheat cultivation in the region. Frost, an important abiotic stress to winter wheat, can occur in many parts of Central Asia any time between late autumn and early spring. During winter frost occurs due a lack of snow cover on wheat fields when temperatures could be below -20¢ªC.   A set of 147 winter wheat genotypes from diverse origin, which was planted in replicated yield trials in Uzbekistan and Turkmenistan, experienced frost during mid December 2012. This resulted in up to 100% damage to many wheat genotypes. There were arrays of variations among the wheat genotypes for tolerance measured as percent crop stand. Nine of the 147 genotypes had >80% crop stand at the end of the winter. More than 50% of the experimental genotypes had severe frost damage as shown by their <20% crops stand. This shows that there is only limited frost tolerance among the elite germplasm adapted to Central Asia. The genotypes showing tolerance to frost conditions could be valuable as potential new varieties in the region. These frost tolerant genotypes could also be used as parents in the crossing programs for developing frost tolerant winter wheat varieties.  The results of this study have important implications for national winter wheat breeding programs in Central Asia as well for International Winter Wheat Improvement Programs involved in germplasm exchange in the region.