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[Objective] The present paper aimed to look for a new way for collecting germplasm resources of wheat resistant to pre-harvest sprouting ( PHS). [Method ] The I, II and Ill batches of the seedlings of wheat grain left in the field from July 1 to July 31, August 1 to August 31 and September 1 to October 10 were collected, which were transplanted into observation nursery and in the middle of October, respectively.[Result] Through the observation of growth consistency, it was found that 93 % of the seedlings of wheat grain left in field in the I batch had the same direct agronomic traits as the wheat varieties planted in the previous crop, while the direct agronomic traits in the II and Ill batches were different. It was found that 94. 1 % of the I batch of the seedling of wheat grain left in the field were susceptible to sprouting, and only 3 . 6% and 2 . 3 % of the seedlings were moderately resistant and resistant, all of the II and Ill batches of the seedling of wheat grain left in the field showed higher resistance to PHS than the middle level, and the later the collection batch was, the higher the proportion of high resistance PHS single ear was; Through the analysis of growth environment factors of wheat seedling with resistance to PHS, then artificial distant hybridization was carried out, it was found that the seed setting rate of artificial distant hybridization between Aegilops tauschii Coss grown in the same field as the wheat seedlings and common wheat was 5 %, which fully proved the possibility of natural cross between A. tauschii and Triticum aestivum in the field; Detecting and analyzing the genomic DNA of ten wheat seedlings with the highest resistance to PHS, A. tauschii Coss, wheat varieties which were mainly cultivated near 10 years in the same field, the primers Xgdm33 and Xgwm52 not only detected a large number of DNA fragments from A. tauschii Coss, but also detected DNA fragments homologous to the previously planted wheat varieties, it was proved that the seedling of wheat grain left in the field was the offspring of natural hybridization between A. tauschii Coss growing in the field and previously planted wheat. [Conclusion] Using the method collecting the seedling of wheat grain left in the field, the wheat germ plasm resources with high resistance to PHSit could be obtained. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to clarify the genetic background of strawberry hybrids and their parents. [Method] 10 ISSR primers were selected for genetic background analysis of strawberry hybrids and parents. We used the 10 ISSR primers to analyze 12 strawberry cultivars with complex genetic background. [Result] Between the parents, parents and their hybrids, parent and its tissue cultivating variants, the average genetic distances were 0. 3258,0. 2607 and 0. 1981 respectively, and the average genetic similarity coefficient were 0.6551, 0.7478 and 0.7672, respectively. The clustering analysis and multidimensional scaling analysis confirmed that strawberry cultivars had a relatively narrow genetic background between the tested materials, indicating that the selected 10 lSSR primers can be a powerful tool for strawberry genetic background analysis. [Conclusion] The genetic background analysis of strawberry will lay a foundation for germplasm innovation. [ABSTRACT FROM AUTHOR]

It has great significance for screening pepper germplasm or breeding new cultivars to identify accurately the resistance levels of peppers. In this paper, the resistance levels of pepper seedlings to Phytophthora root rot at different growth stages were investigated by irrigating inoculation with zoospore suspension of Phytophthora capsici isolates that belonged to prevalent race 3 from Yunnan. The results showed that resistance, moderate resistance and susceptible pepper seedlings against Phytophthora capsici had significant differentiation under 20 - 25 °C when inoculated at 20 d ( cotyledon stage ), 40 d ( 3 - 4 leaf stage ), 60 d ( 5 - 6 leaf stage ) and 90 d ( early squaring ). That is, resistance levels from strong to weak at different growth stages of pepper seedlings were 90 d > 60 d > 40 d > 20 d, which suggested that resistance levels of peppers were positively correlated with seedling ages. The pepper seedlings inoculated by irrigation at 60 d ( 5 - 6 leaf stage ) could reflect the true resistance of different pepper cultivars. This study defined the suitable growth stage for resistance evaluation of Phytophthora root rot disease on pepper and also provided a scientific basis for screening and identification of the pepper germplasms or resistance cultivars. [ABSTRACT FROM AUTHOR]