Genetic Contribution of Emmer Wheat (Triticum dicoccon Schrank) to Heat Tolerance of Bread Wheat

Abstract

Rising global temperatures cause substantial yield losses in many wheat growing environments. Emmer wheat (Triticum dicoccon Schrank), one of the first wheat species domesticated, carries significant variation for tolerance to abiotic stresses. This study identified new genetic variability for high-temperature tolerance in hexaploid progeny derived from crosses with emmer wheat. Eight hexaploid and 11 tetraploid parents were recombined in 43 backcross combinations using the hexaploid as the recurrent parent. A total of 537 emmer-based hexaploid lines were developed by producing approximately 10 doubled haploids on hexaploid like BC1F1 progeny and subsequent selection for hexaploid morphology. These materials and 17 commercial cultivars and hexaploid recurrent parents were evaluated under two times of sowing in the field, in 2014–2016. The materials were genotyped using a 90K SNP platform and these data were used to estimate the contribution of emmer wheat to the progeny. Significant phenotypic and genetic variation for key agronomical traits including grain yield, TKW and screenings was observed. Many of the emmer derived lines showed improved performance under heat stress (delayed sowing) compared with parents and commercial cultivars. Emmer derived lines were the highest yielding material in both sowing dates. The emmer wheat parent contributed between 1 and 44% of the genome of the derived lines. Emmer derived lines with superior kernel weight and yield generally had a greater genetic contribution from the emmer parent compared to those with lower trait values. The study showed that new genetic variation for key traits such as yield, kernel weight and screenings can be introduced to hexaploid wheat from emmer wheat. These genetic resources should be explored more systematically to stabilize grain yield and quality in a changing climate.

A strategy of ideotype development for heat‐tolerant wheat

“…High temperature significantly affected trait expression in late sown environment particularly at grain‐filling stage. Further details of climate data are presented in Ullah et al ().…”

“…Details of the experimental site, genetic materials and the experimental design can be found in Ullah et al (). Briefly, a diverse population of 554 hexaploid genotypes was evaluated for heat stress under field conditions.…”

Assessment of morphological and anatomical variability in Triticum species, Aegilops species, interspecific and intergeneric hybrids

“…Ancient wheat species, landraces, wheat wild relatives, and wheat hybrids offer biotic and abiotic stress tolerance, high biochemical and micronutrient contents, and quality in the improvement of new cultivars (Mathre et al, 1985;Cakmak et al, 2010;Arzani and Ashraf, 2017;Li et al, 2018;Ullah et al, 2018;Kishii, 2019). Wild wheat relatives and different wheat species have also been used as donors of drought tolerance in water deficit conditions (Peng et al, 2013;Ikanović et al, 2014;Suneja et al, 2019).…”

Root-based characterization of intergeneric hybrids with Triticum and Aegilops species in early vegetative and stem elongation growth stages

“…The oldest cultivated and hulled wheat genotypes, spelt wheat (T. spelta), einkorn wheat (T. monococcum), emmer wheat (T. dicoccum), and Vavilov wheat (T. vavilovii), are found among the wild and modern wheats (Adu et al, 2011). Different cultivated and wild species of wheat, landraces, and wheat hybrids offer biotic and abiotic stress tolerance, high biochemical contents, and quality in the improvement of new cultivars (Mathre et al, 1985;Arzani and Ashraf, 2017;Li et al, 2018;Ullah et al, 2018;Kishii, 2019).…”