Alteration of drought tolerance of winter wheat caused by translocation of rye chromosome segment 1RS

In Hungary 53% of wheat (Triticum aestivum L.) cultivars registered during the last twenty years carry the 1RS translocation, the short arm of rye (Secale cereale L.) chromosome 1. Wheat production in Hungary is limited primarily by drought. Despite the widespread use of this translocation there is no information about its effect on stress tolerance. The objective of this study was to investigate the effect of 1BL. 1RS on drought tolerance. 'Mv5791-1B. 1R' and the sister line 'Mv5791-1B.IB' were examined among other cultivars in greenhouse under well-watered and drought conditions. Data were obtained for anthesis- and maturity date, plant height, root/shoot ratio, components of grain yield, Harvest Index (HI) and Water Use Efficiency (WUE). The translocation line had higher root- and shoot dry weight in both treatments and an increased root/shoot ratio, which was more than the sister line in dry treatment (69 and 38%, respectively). The larger root biomass of the 1RS translocation line could contribute to the increased HI and WUE under drought that resulted in less yield decrease (23 and 32%, respectively) compared with the non-translocation counterpart.