关键词: 新疆杏品种; 花器官表型性状; 亲缘关系; 遗传多样性

Abstract: 【Objective】 To analyze the phenotypic characteristics of flower organs and pollen microscopic characteristics of apricot varieties and to discuss the genetic diversity and genetic relationship among apricot varieties in Xinjiang in the hope of providing a reference for the evaluation, identification and utilization of apricot resources in Xinjiang.【Methods】 The phenotypic characteristics of flower organs of 41 apricot varieties in three subpopulations (Kashi subgroup, Hetian subgroup, Kuche subgroup) were measured, field observation of phenotypic indicators of flower organs, and the microscopic morphological characteristics of pollen were observed by scanning electron microscope (SEM). The coefficients of average, standard, coefficient of variation, Simpson diversity index and Shannon-weaver diversity index of indicators related to genetic diversity of 21 phenotypic traits were calculated. The cluster analyses of phenotypic characters of flower organs and 11 pollen microcharacteristic traits of 41 apricot varieties were conducted.【Results】 The cluster analysis of flower organs showed that when the genetic distance was 15.0, the 41 varieties of the three subpopulations could be divided into four groups. There were 30 varieties in group I, including 10 varieties of Muzijianali in Hotan subgroup, 11 varieties of Xiheiyexing in Kashi subgroup and 8 varieties of Kabakeximixi in Kuche subgroup; there were 4 varieties in group II, including 2 varieties of Luopuhongdaike, Cuijianali in Hotan subgroup and 1 variety of Huangqiligan in Kuche subgroup; only in group III In Kuqa subgroup, there were 1 variety of Keziximixi and 8 varieties of rough black leaf apricot in group IV. The results of cluster analysis of micro morphological characteristics of pollen showed that when the genetic distance was 15.0, 41 varieties from three subgroups were grouped into two groups. There were 36 varieties in group I, including 13 varieties such as Gumuxing in Hetian subgroup, 12 varieties such as Qiaoerpang in Kashi subgroup, 11 varieties such as Kabakeximixi in Kuche subgroup, and 5 varieties such as Yechengheiyexing in group II species. Among the 41 apricot cultivars in Xinjiang, the genetic variation coefficient of pore frequency was the largest, the genetic variation coefficient of petal number was 1.85, the variation range of genetic variation coefficient was 1.85%-75.68%, the average value was 16.18%; the Shannon Weaver index range was 5.01-5.43, the average value was 5.33; the Simpson index range was 0.97-0.98, and the average value was 0.97. 【Conclusion】 The 41 apricot varieties tested in Xinjiang had close genetic relationship and rich genetic diversity, which were mainly reflected in five aspects: petal color, petal shape, single flower weight, aperture and pore frequency. Among the 21 phenotypic indexes, the variation of pore frequency was the most abundant, the variation of petal number was the least, and the genetic stability was good. Petal aspect ratio, single flower weight, petal color, petal shape, aperture and pore frequency were important indexes for phenotypic diversity observation.

Key words: Xinjiang apricot; flower organ; pollen micromorphology; genetic relationship