Genetic Diversity of Fruit Phenotypic Traits of Wild Pyrus ussuriensisMaxim
Objective The genetic variation and diversity of morphological traits, volatile components, sugars and organic acids of wildPyrus ussueiensisifruits were investigated to provide a scientific basis for resource protection and utilization.[Method] Using 35 seedlings of wildP. ussuriensis collected from the germplasm resources nursery and 3 cultivars (Xiaoxiangshui, Nanguo, Jingbai), the ripened fruit vertical length, transverse length, shape index and weight, and the sugars, organic acids were measured by using the Head space-solid phase microextraction, gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC).[Result] The variation coefficients (CV) of fruit size, content of total volatile compound, numbers and contents of volatile compounds, the segregation ratios and contents of main volatile components, contents of sugars and organic acids, and contents of total sugars and organic acids were over 17%, which revealed significant differences and extremely abundant genetic diversity in 35 seedlings of wild P. ussueiensisi. The further comparison with three cultivars indicated that fruit vertical length, transverse length and weight of wildP. ussuriensisare smaller than that of the fruit of cultivars but have the similar fruit shape indexes. On average, 41 fragrance components were detected in wildP. ussuriensis, being obviously higher than the amount of fragrance components in the fruits of cultivars which contain 25 fragrant components. The average amount of aromas reached 9.44μg·g-1, which is significantly higher than that of 3 cultivars (5.71 μg·g-1). The wildP. ussuriensis contains organic acid and hydrocarbon derivatives, the 2 special compounds in wild pears, and it also contains other 111 special components which include esters and were categorized into 9 classes. In all, 16 characteristic fragrant components were detected in wildP. ussuriensisand three cultivars. Among them, 1-hexanol, hexanal and other 8 fragrant components commonly exist in both wildP. ussuriensis and three cultivars, serving as the characteristic aromas for both. And hexyl acetate, pentyl acetate and other 6 compounds were unique fragrant aromas for the fruit of wildP. ussuriensis. Three sugars (fructose, glucose and sucrose) and 6 organic acids (malic acid, tartaric acid, citric acid, oxalic acid, lactic acid and succinic acid) almost could be detected in 35 wild seedlings and 3 cultivars with fructose and malic acid showing the highest amount. The contents of tartaric acid and sucrose in the wild seedlings and the content of total sugars and organic acids in some wild seedlings were significantly higher than those of 3 cultivars.[Conclusion] There were extensive genetic variation in fruit morphological traits, aroma components, sugars and organic acids components in wildP. ussueiensisi, and 35 seedlings presented significant differences. The genetic diversity of wildP. ussueiensisiwas extremely abundant, 111 volatile compounds were unique components in wildP. ussueiensisi, and acids, hydrocarbon derivates were not found in the cultivars. It indicated that the wildP. ussueiensisi has a large potential for further selection.
国家科技期刊平台
NSTL
万方数据
维普
