关键词: 观赏海棠, 自然杂交后代, 遗传多样性, AFLP分析

Abstract: Based on morphological characters and AFLP molecular markers，genetic variations were investigated in 50 natural hybrid progenies of ornamental crabapple，Malus‘Royalty’. The results showed that there were significant plentiful morphological traits within the seedlings. The coefficient of variation ranged from 3.44% to 42.68% in the 18 morphological parameters of leaf and flower. Among them the parameter including stipule length and width，leaf area，leaf fresh weight，petal width or flower stalk length had a coefficient of variation above 20%，showing a significant morphological diversity. Based on AFLP markers，9 primers were amplified into 349 bands and 86.8%（303 bands）of them were polymorphic. The Nei’s genetic diversity indices and the Shannon information indices were observed at the range of 0.24–0.36 and 0.36–0.53 respectively. The analysis indicated that there are large genetic variations in molecular level and，especially，in morphology characters of the natural hybrid progenies. These variations may provide advisable materials for the selection breeding of ornamental crabapple.

Key words: ornamental crabapple, natural hybrid progeny, genetic diversity, AFLP