Stress tolerance in hexaploid spring triticale under Mediterranean environment

The development of triticale (X Triticosecale Wittmack) cultivars which are tolerant to drought and heat stress is an objective in many breeding progr ammes, but so far success has been limited. This study was conducted to det ermine the susceptibility index (S) of triticale under stress conditions. T wenty genotypes were grown in replicated trials and evaluated for heat and drought tolerance under natural conditions at Adana, Turkey, from 1992 to 1 996. Among the advanced lines of triticale, genetic variation for adaptatio n to heat and drought conditions-typical features of the Mediterranean envi ronment - was determined. The best yielding lines under stress, hence havin g a low susceptibility index, were Lynx/Yogui and Zebra 31. The implication s of these findings for triticale breeding in stress environments are discu ssed.