[Objective] This study aimed to investigate the influences of UV-C irradiation on seed germination and seedling growth of winter wheat. [Method] Winter wheat cul- tivar Liaoda 02 was selected as the experimental material and irradiated with UV-C for 1 h,to compare the dynamic changes of seed germination rate under different treatment time and the changes of gibberellin （GA） content and a-amylase activity during the germination process after UV-C irradiation. Wheat seeds irradiated with UV-C for 1 h were sown, the emergence number, growth speed, fluorescence param- eter, reflectance spectrum, relative conductivity and other related physiological indica- tors of seedlings were determined. [Result] The results showed that the germination rate of dry and wet winter wheat seeds irradiated with UV-C for 1 h was improved, compared with the untreated seeds. After soaked for 6, 8, 10 and 12 h, dry seeds irradiated with UV-C for 1 h showed higher GA content and higher a-amylase activity than the control. In addition, UV-C-irradiated dry seeds also showed faster emergence speed and plant growth speed within the first six days after emergence and greater plant height than the control. The flavonoid content in leaves of the treatment group was also increased compared with the control, while the maximal photochemical effi- ciency （Fv/Fm）, photo-chemical reflectance index （PRI）, chlorophyll and carotenoid content were rarely influenced. In conclusion, UV-C irradiation could improve the ger- mination rate of dry seeds and wet seeds soaked for a certain time, especially for wet seeds soaked for 1 h. Furthermore, UV-C-irradiated seeds showed improved ger- mination speed and plant growth. [Conclusion] This study laid the foundation for ex- ploring the effect mechanism of ultraviolet rays on seed generation.
In this study, wild rice chromosome segment substitution lines bred by Yuanjiang common wild rice and elite indica rice variety Teqing were used as ex-perimental materials to detect aluminum tolerancerelated QTLs based on the phe-notypic data of indoor and outdoor plant height inhibition rate and dry weight inhibi-tion rate at seedling stage. According to experimental results, 11, 18, 14 and 5 QTLs related with aluminum tolerance were detected respectively on different chro-mosomes. Analysis of phenotypic data of indoor and outdoor plant height inhibition rate indicated that QTLs around RM38 on chromosome 8 and RM277 chromosome 12 exhibited the highest contribution rates （12% and 11%）, belonging to major QTLs. Analysis of phenotypic data of indoor and outdoor dry weight inhibition rate indicated that the highest contribution rate was only 9% and 8%; therefore, no major QTL was detected. QTLs detected repeatedly were located on chromosomes 7, 8, 9, 11 and 12, respectively. Two QTLs were located on chromosome 8. QTLs around RM310 were detected three times and other QTLs were detected twice, which were identified as stable QTLs.
Drought stress is one of the major factors affecting in wheat yield and grain quality. In order to investigate how drought stress might influence wheat quality during grain filling, three wheat cultivars Gaocheng 8901, Jagger and Nongda 3406 were subjected to drought stress during the grain filling stage. Neither globulin and glutenin, nor the relative percentage ofamylose significantly changed following drought treatments, whereas albumin and gliadin concentrations did. The SDS-sedimentation, which has a strong linear correlation with wheat baking quality was markedly decreased following drought stress. These results indicated that drought had an adverse effect on wheat qualit3,. In order to investigate the protein complexes in the wheat flour, the data from native PAGE and SDS-PAGE were combined and a total of 14 spots were successfully identified, and of these eight protein types were determined to be potential complex forming proteins.
With the increase in consumer demand,wheat grain quality improvement has become a focus in China and worldwide.Transcriptome analysis is a powerful approach to research grain traits and elucidate their genetic regulation.In this study,two cDNA libraries from the developing grain and leaf-stem components of bread wheat cultivar,Nongda211,were sequenced using Roche/454 technology.There were 1061274 and 1516564 clean reads generated from grain and leaf-stem,respectively.A total of 61393 high-quality unigenes were obtained with an average length of 1456 bp after de novo assembly.The analysis of the 61393 unigenes involved in the biological processes of the grain showed that there were 7355 differentially expressed genes upregulated in the grain library.Gene ontology enrichment and the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis showed that many transcription products and transcription factors associated with carbohydrate and protein metabolism were abundantly expressed in the grain.These results contribute to excavate genes associated with wheat quality and further study how they interact.
Liu WEIZhihui WUYufeng ZHANGDandan GUOYuzhou XUWeixia CHENHaiying ZHOUMingshan YOUBaoyun LI
