Fusarium head blight (FHB) is a devastating disease lowering the yield and quality of wheat. Intensive use of limited allelic pools critically affects wheat resistance, while advancing pathogenic alleles. This study presents new alleles raised from moderate rather than elite crosses. ‘Parshall’ has indigenous moderate resistance that was crossed with the moderate susceptible ‘Reeder’ and developed the 110 RIL population (noted as PR) that was tested across three states and years in the USA, under open-field and greenhouse conditions. Heading- and FHB-related traits of incidence, severity, and index were assessed. A genetic map (1417 cM) of SNP/DArT markers was generated. Composite interval mapping produced 45 QTL. Permutated LOD assessment identified two consistent QTL (4AL and 4BL) of type I and II resistance. Significant markers at the 4A QTL showed correlation with previous FHB resistance, while at the 4B QTL with pathogen responsive regions. The 1- and 2-D genome scans identified 16 QTL and six pairs of interacting markers for resistance, with additive effects between 0.17% and 2.19%; respectively. Additionally, additive × environment interaction was between 0.04% and 3.18% confirming the high environmental effect. Three pairs of QTL with additive × additive effects between 0.15% and 0.30% were revealed by FHB epistasis. However, the additive × additive environmental interaction at these three loci varied between 0.03% and 1%, confirming the G × E effect on FHB resistance. Hidden heritable epistasis was discovered in PR-population for FHB resistance. PR-alleles will help breeders develop lines mitigating epidemic environments and changeable climates, to boost yield facing hanger, food scarce, and secure worldwide penurious economies.

The rebaudioside-A/stevioside (R/S) ratio influences the breeding and commercial values of stevia genotypes. Three stevia genotypes, “High Sugar,” “Levan,” and “ShouA3-2,” with respectively high, medium, and low steviol glycoside (SG) contents were investigated to answer the following questions: how do SG contents change when NaCl induces gene expression? Is SG-content positively correlated with NaCl tolerance? Does the genotype, with a high R/S ratio, exhibit higher expression of SG genes; compared to the genotype, with a low R/S ratio? Growth parameters, through our results, were decreased in “High Sugar” and “ShouA3-2” relative to “Levan” who showed better performance under the severe 200 mM NaCl treatment. Extendedly, “High Sugar” decreased the expression of SG-genes (cpps, ks, kh, and ugt74) under the low 50 NaCl treatments, while the “ShouA3-2” has upregulated all the genes (except ks) under the moderate (100 mM) NaCl treatments. Overall, the antioxidant sod1 gene was upregulated, similarly, the “Levan” has upregulated the cpps, while differentially expressed ks and kh across the NaCl treatments. In conclusion, high R/S ratio does not necessarily mean enhancement in responses to abiotic stresses in stevia. The R/S ratio in stevia does not solely rely on the expression of SG-pathway genes thus; other ancestral genetic elements may independently regulate them. Under salinity, the rooting characteristics improved when R/S ratio was low, while when moderate the shooting characteristics were superior. We recommend breeding for moderate R/S ratios to assure probable resilience to challenging climates (such as salinity) and potent higher agronomic traits.

Fusarium head blight (FHB) is a devastating disease lowering yield and quality of wheat. Intensive use of limited allelic pools critically affects wheat resistance, while advances pathogenic alleles. This study presents new alleles raised from moderate rather than elite crosses. ‘Parshall’ has indigenous moderate resistance that was crossed with the moderate susceptible ‘Reeder’ and developed the 110 RIL population (noted as PR) that was tested across three states and years under field and greenhouse conditions. Heading- and FHB-related traits of incidence, severity, and index were assessed. A genetic map (1417cM) of SNP/DArT markers was generated. Composite interval mapping produced 45 QTL. Permutated LOD assessment identified two consistent QTL (4AL and 4BL) of type I and II resistance. Significant markers at the 4A QTL showed correlation with previous FHB resistance, while at the 4B QTL with pathogen responsive regions. The 1- and 2-D genome scan identified 16 QTL and six pairs of interacting resistance markers; respectively, with additive effects between 0.17% and 2.19%. Additionally, additive×environment interaction was between 0.04% and 3.18% confirming the high environmental effect. Three pairs of QTL with additive×additive effects between 0.15% and 0.30% were revealed by FHB epistasis. However, the additive×additive environmental interaction at these three loci was varied between 0.03% and 1%, confirming the G×E effect on FHB resistance. Our results have broadened the allelic pool of wheat resistance. PR-alleles can help breeders to develop lines mitigating epidemic environments and changeable climates, to boost yield facing hanger, food scarce, and unsecure worldwide penurious economies.