Simultaneous selection of high-yielding and drought-tolerant barley landraces using GT, GYT and GYSI methodologies

Locally adapted landraces are the major barley varieties welcomed in the desert climate regions of Iran. These germplasms have potentials in terms of yield and drought tolerance which makes their evaluation worthwhile. To this end, fifty barley landraces along with six check varieties (Nosrat, Yoused, Nimroz, Goharan, Mehr and Khatam) were evaluated under well-watered and drought conditions during 2019-2020 and 2020-2021 growing seasons. The data were analyzed by GT (genotype by trait) biplot and GYT (Genotype by yield*trait) biplot method. Additionally, drought stress tolerant and susceptibility indices, including TOL, SSI, YSI, HM, GMP, MP and STI, were calculated and utilized in the GYT biplot which denominated as GYSI (Genotype by yield*stress index) biplot in this paper. Referring to ATC view and SI ranking of GYT data, 27 genotypes under well-watered and 27 genotypes under drought stress were selected which all were above average with the positive SI values. Likewise, 25 above average drought-tolerant genotypes were identified based on GYSI methodology. Based on the results, plant height and YSI were defined as ideal trait and stress index in combination with grain yield to identify superior genotypes, respectively. Overall, our study determined 12 genotypes which meet all the criteria to achieve high yield and drought tolerance. It could be concluded that combination of GT, GYT and GYSI methodologies led us to simultaneous selection of high-yielding and drought-tolerant genotypes accurately among locally adapted barley landraces of Iran.