Description: High temperature and drought are the most important abiotic stress factors which influence the wheat production in major parts of the wheat grown areas in Iran. This study was conducted to identify the proper criteria (morphological or physiological markers) for screening the heat and drought tolerant wheat genotypes under field conditions as well as to find out the sources of terminal heat and drought tolerance for utilization in the breeding programs. Under dryland, supplemental and full irrigation (exposed to high temperatures after anthesis), nine bread wheat genotypes were evaluated in three separate experiments at Gachsaran agricultural research station which is located in southwest of Iran in 2010-2011