Screening of spring wheat (Triticum aestivum L.) germplasm against drought and heat stress

Drought and heat stress are major indicators of global climate change and yield-limiting factors in wheat. Moreover, simultaneous occurrence of both factors could increase the injuries and greater yield losses in wheat species. In this scenario, there is need to screen germplasm and develop breeding lines which may show better resistance under the targeted condition. A germplasm comprising of 17 advanced lines, 4 elite checks and 79 accessions was compared to determine their resistance under controlled osmotic (- 0.9 MPa) and heat stress (40 degrees C) on the basis of various seedling traits. Heat and drought resistance index showed significant positive relationship with root mass showing the importance of this trait for selection under stress condition. Germplasm accession such as NARC-11022 possessed the highest drought and heat resistance index while standard check such as FSD-08 had the highest drought resistance index. These accessions may be exploited in breeding cultivars for multiple stress condition. Some advanced lines such as SU-100, SU-159 showed promising results under both types of stress, and these lines may be recommended for stress-prone environment.