Identification of Durum Wheat Cultivars and Their Tetraploid Relatives with Low Cadmium Content

U ovom su radu okarakterizirani genotipovi 71 kultivara tvrde pšenice (Triticum durum Desf.), 22 kultivara dvozrnca (Triticum dicoccum L.) i 11 kultivara divlje dvozrne pšenice (Triticum dicoccoides L.) u svrhu pronalaska alela povezanih s većim udjelom kadmija. Nakon toga je uzgojem u posudi ispitan fenotip 14 odabranih kultivara s malim i velikim udjelom kadmija, radi potvrde genotipskih podataka. Identificirana su 32 genotipa tvrde (durum) pšenice, jedan kultivar dvozrnca i četiri kultivara divlje dvozrne pšenice koji sadržavaju alele povezane s velikim udjelom kadmija, te 68 genotipova koji sadržavaju alele povezane s malim udjelom kadmija, i to 39 kultivara durum pšenice, 21 dvozrnca i 7 divlje dvozrne pšenice. Povrh toga, fenotipske karakteristike uočene nakon uzgoja u posudama potvrdile su rezultate molekularne analize. Marker je uspješno upotrijebljen za klasifikaciju kultivara durum pšenice u one s velikim ili malim udjelom kadmija, pa je zaključeno da se može upotrijebiti u programu uzgoja novih kultivara durum pšenice koja sadržava alele povezane s malim udjelom kadmija. Zbog rutinske primjene fosfornih gnojiva na poljoprivrednim površinama i utjecaja ostalih antropogenih čimbenika što dovode do akumulacije toksičnog kadmija, treba čim prije razviti nove kultivare durum pšenice s malim udjelom kadmija za sigurnu proizvodnju makarona i ostalih tipova pšeničnih proizvoda za prehranu ljudi i ishranu stoke.In this study, 71 durum wheat cultivars (Triticum durum Desf.), 22 emmer wheat (Triticum dicoccum L.) and 11 wild emmer (Triticum dicoccoides L.) genotypes were genetically characterized to determine the alleles associated with high cadmium (Cd) content. After genotypic characterization, 14 cultivars selected among all genotypes with low and high Cd content were phenotyped by a pot experiment to verify the genotypic data. Identification of 32 durum wheat, one emmer wheat and four wild emmer genotypes showed that they have alleles associated with high Cd content, while 68 genotypes of which 39 durum wheat, 21 emmer wheat and 7 wild emmer cultivars had alleles associated with low Cd content. Moreover, phenotypic data obtained from pot experiment were similar to the molecular data. To sum up, the marker successfully classified durum wheat cultivars into either high or low accumulators and these results can be safely used in breeding programs to improve new durum wheat cultivars with alleles associated with low Cd content. Due to routine use of phosphorus fertilizers in agricultural areas and other anthropogenic factors related to Cd toxicity, new durum wheat cultivars with low Cd content should be urgently developed for safe production of macaroni or other types of wheat products for human and animal consumption

Evaluation of resistance of Turkish bread wheat (Triticum aestivum) varieties to recently emerged Puccinia striiformis f. sp. tritici races

Using genetic diversity has made significant contribution to stripe rust resistance to improve wheat production. However, rapid evolution of the Puccinia striiformis f. sp. tritici (Pst), and emergence of virulent races can negatively affect the wheat genotypes with race-specific resistance gene(s). In this study, reactions of 130 bread wheat varieties, released from 1931 to 2014, were evaluated to recently emerged Pst races in Turkey, PSTr-6 and PSTr-23, at seedling and adult-plant stages. 65.4% and 67.7% of wheat varieties showed susceptible reaction to PSTr-6 and PSTr-23 at seedling stage, respectively. Moreover, coefficient of infection (CI) values generated by infection type (IT) and disease severity (DS) data demonstrated that PSTr-23 (59.78) was more virulent than PSTr-6 (57.93) at adult-plant stage. In addition to these, the presence of important yellow rust (Yr) genes in these varieties was investigated at molecular level. It was determined that the frequencies of three Yr genes, Yr5, Yr10 and Yr15, among these varieties were 1.5, 6.2 and 3.8%, respectively. However, none of them had Yr36 and only one variety had Yr5+Yr10 combination with frequency of 0.7%. In conclusion, most varieties have not these Yr genes and possess a moderately resistance/susceptible reaction to both races in general. © 2022 Elsevier Lt

Resistance to stripe rust in Turkish durum wheat varieties and wild emmer genotypes

Stripe or yellow rust caused by Puccinia striiformis f. sp. tritici (Pst) is the most important disease of wheat causing significant yield losses. Growing resistant varieties is the most efficient and sustainable way to control this disease. The aim of this study was to investigate molecularly the presence or absence of the major resistance genes Yr5, Yr10 and Yr15 to stripe rust in 54 Turkish durum wheat (Triticum turgidum var. durum) varieties and 11 wild emmer (Triticum turgidum var. dicoccoides) genotypes. In addition, field trials were conducted during 2019–2020 under natural epidemic conditions in Antalya to determine phenotypic reactions of these genotypes against stripe rust. As a result of molecular analyses, none of the 54 durum wheat varieties had Yr5 resistance gene; however, the resistance genes Yr10 and Yr15 were determined in 12 and 17 varieties, respectively. Moreover, 7 of these varieties had both Yr10 and Yr15 genes. None of 11 wild emmer accessions had resistance genes examined. It was also determined that 28 varieties had resistant reaction to Pst race(s) under natural infection conditions whereas all wild emmer accessions were highly susceptible. This is the first study to identify major Yr-genes in Turkish durum wheat varieties and, therefore, these findings can be beneficial in wheat breeding programs to be conducted for resistance to stripe rust