Genetic Characterization and Agronomic Evaluation of Drought Tolerance in Ten Egyptian Wheat (Triticum aestivum L.) Cultivars

Abstract

This investigation was carried out for genetic characterization and determination of drought tolerance of ten Egyptian cultivars of wheat (Triticum aestivum L.), namely Misr 1, Misr 2, Gemmiza 9, Gemmiza 10, Gemmiza 11, Gemmiza 12, Shandawel 1, Giza 168, Giza 171, and Sids 14. These cultivars were grown in two winter seasons: 2018/2019 and 2019/2020 at the experimental farm Fac. of Agric., Suez Canal Univ., Ismailia, Egypt, under two watering regimes: normal (100%) and stress (50% FC) conditions. Six agronomic traits and five tolerance indices, namely stress tolerance (TOL), mean productivity (MP), geometric mean productivity (GMP), yield stability index (YSI), and drought susceptibility index (DSI), were used to evaluate the impact of drought stress. The results reflected Giza 171, Misr 2, and Giza 168 as precious germplasm for breeding of high-yielding drought-tolerant wheat. A highly significant positive correlation was recorded between yield under normal and stress conditions on the one hand and each of MP and GMP on the other hand. In addition, YSI appeared engaged in a highly significant positive correlation with yield under drought conditions only. TOL and DSI appeared insignificantly correlated with yield. Therefore, MP and GMP were reflected as the first runners among indices suitable to distinguish the high-yielding cultivars under drought conditions. At the molecular level, five primers of Start Codon Targeted (SCoT) markers were able to resolve and characterize the studied cultivars, which reflected SCoT as a potent gene-targeting molecular marker, able to characterize and resolve genetic diversity in wheat at the cultivar level using few primers. Therefore, SCoT is a time-efficient molecular marker, and it can efficiently replace indices in characterization of drought-tolerant genotypes with a high confidence level and reasonable cost.

Genetic improvement for drought tolerance in rice using mutation induction

“…The amplification of unique SCoT bands in drought-tolerant genotypes was also recorded by Shaban et al (2022). In harmony with our results, Emam et al (2022) amplified unique SCoT bands with drought tolerance. Therefore, SCoT can be applied to differentiate between different drought stress tolerances according to markers associated with new alleles for this trait in given selected genotypes.…”

The role of endophytes and rhizobacteria to combat drought stress in wheat

“…Further research is required to elucidate the mechanisms by which PGPR regulate water and to optimize their application in agriculture. PGPR have been found to have a significant influence on the plants relative water content (El-Mageed et al, 2022). In conclusion, endophytic and rhizobacterial maintain the better root growth that can ensure the better water uptake to counter the toxic effects of drought.…”

“…Classical breeding programs can be utilized to identify and incorporate drought tolerance mechanisms in crops that are suitable for water-limited regions (Han et al, 2020). In a study conducted by Emam et al (2022) the consequence of drought and irrigation on productivity and yield-related traits of wheat cultivars was assessed. The findings indicated that wheat genotypes exhibiting favorable characteristics associated with grain production could be selected for both irrigated and water-stressed environments.…”

Assessment of drought tolerance of sesame germplasm with agronomic and quality traits

“…Sravanthi et al (2022) identified two drought-tolerant genotypes which had stable performance under both stress and irrigated conditions. Screening diverse genotypes for drought tolerance under different drought conditions was also conducted with the use of different crops such as cowpea (Fatokun et al, 2012), sorghum (Naoura et al, 2019), peanut (Abadya et al, 2021), and wheat (Emam et al, 2022), resulting in selection of higher yielding genetic resources. Therefore, assessment of diverse germplasm collections can be sourced for drought tolerance and agro-quality traits to select unique lines for breeding.…”