Oats are an important grain-feeding crop with strong saline–alkali tolerance; however, the genetic mechanism of this tolerance is not clear, which hinders the development of oat varieties adapted to saline soils. In this study, the saline–alkali tolerance of 524 oat germplasm resources was comprehensively evaluated using culture-dish germination and field identification methods. During the germination period, saline–alkali stress significantly inhibited the germination potential, germination rate, and shoot and root lengths of oat germplasm. The indicators decreased by 71.15%, 49.32%, 59.03%, and 63.90%, respectively. The relative value of each trait was used as the evaluation metric. The 524 oat germplasm resources were classified into five groups by cluster analysis, and 174 oat germplasm resources with saline-alkali tolerance at the germination stage were screened. A regression equation for the identification of germinated saline-alkali-tolerant oat germplasm resources under the same conditions was also established. The field experiment showed that the coefficients of variation of oat germplasm resources were 4.03–54.12% and 6.97–38.50% in the two locations, which was rich in genetic variation; the correlation analysis showed that the biological yield was positively correlated with the D-value, and 18 high–quality and high-yielding saline–alkali-tolerant oat germplasm resources were identified by combining the saline–alkali-tolerant and weak germplasm resources of the two locations. Based on the multidimensional evaluation of germination and field performance, the 18 saline–alkali–tolerant germplasms screened in this study provide high–quality germplasm resources and a theoretical basis for saline oat cultivation and saline-tolerant breeding.

Background: pre-harvest sprouting (PHS) is a significant cause of yield loss in cereal crops, and is an important topic of study for the improvement of wheat quality. Many studies have focused on PHS in wheat during the last 10 years, especially on the involvement of abscisic acid (ABA) in PHS, however, a lot remained unknown about this topic.Results: In this study, a PHS resistant line was isolated from an ethylmethane sulfonate (EMS) mutant population derived from the wheat cultivar ‘Long 13-3778’, namely ‘LQ18’. The mutant line LQ18 showed highly significant resistance to PHS compared with the wild-type. Transcriptome sequencing was conducted to determine the differences between the LQ18 mutant and the wild-type at the level of gene expression. The results showed no conclusive evidence that the ABA biosynthesis and signaling pathways contribute to the differences in PHS between the mutant and the wild-type, and some genes and their alleles associated with PHS tolerance showed differential expression between the mutant and wild-type lines. The most interesting result of this study was that the expression levels of the chitinase family genes showed significant differences between the mutant and the wild-type as determined by GO enrichment analysis, and a subsequent analysis of differential expression profiling of the chitinase genes led to the same conclusion.Conclusions: Transcriptomic analysis in this study have revealed the global transcriptome profiles of the PHS sensitive wheat cultivar ‘Long 13-3778’ and its PHS resistant mutants. Furthermore, this study has proposed a possible explanation of the connection between PHS and the chitinase family for the first time, which added to our understanding of PHS and seed dormancy in common wheat.

Seed shattering is a key cause of yield loss in naked oat (Avena nuda) production, yet research specifically targeting this issue remains limited. This study phenotyped 316 diverse naked oat accessions for 14 floret morphological traits and shattering rate across six environments. Principal component analysis (PCA), K-Means clustering, and path analysis were employed for data mining. PCA identified three principal components representing morphological size, thickness-length trade-off, and differential thickness distribution between lemma and palea. K-Means clustering divided the accessions into two clusters differing significantly in morphological size and seed shattering resistance. Path analysis revealed that palea width showed the strongest negative direct effect on shattering, followed by lemma basal thickness and lemma basal ridge thickness, while seed area exhibited a significant positive direct effect. Indirect pathway decomposition further demonstrated that palea width and lemma basal thickness served as key negative indirect contributors, whereas seed area played a dual role with opposing direct and indirect contributions. The model explained 32.80% of shattering variation, with palea width contributing the largest relative share. These findings suggest that floret morphology is associated with naked oat seed shattering and may inform resistance breeding efforts.