【目的】为突出海棠(Malus spp.)的观果价值,系统开展‘小甜甜’(M. ‘Sweet Sugartyme’)等观果海棠自由授粉子代试验,探索半同胞家系子代表型特征及育种成效。【方法】在重点明确子代果色及果期物候特征的基础上,基于加权的层次分析法(AHP),从果实、花朵、树形、叶片4个表型维度构建海棠子代观赏性综合评价体系。【结果】①根据成熟期果色,100个子代单株可分为3个大类及9个子类,不同色系/子色系海棠子代成熟期果实色彩观赏性差异显著。②自由授粉后,子代群体比母本的挂果期有所延长,成熟期较晚与极晚的类型占比显著升高。根据挂果期长短和成熟期早晚,分别将子代群体划分为5个品种群。③AHP综合评价模型显示,子代单株从Ⅰ级到Ⅳ级,综合观赏性逐渐减弱,G45、G71、G70等Ⅰ级优株果色鲜艳、着果量大且挂果期长;G16和G85虽然综合得分不高,但是其成熟期极晚,挂果期长达258 d,单一性状突出,观赏效果佳。【结论】自由授粉可有效扩大半同胞家系子代群体遗传基础,显著提高种质多样性;以AHP构建的评价体系,评价结果更为准确,能够用于观赏海棠的新品种选育及拓展观赏应用。

【Objective】For a long time, the breeding goal of crabapple has mainly centered on the flower traits, while its fruit ornamental value has been overlooked. To emphasize the fruit ornamental value of crabapple, we conducted experimental studies on the fruit Malus offspring like ‘Sweet Sugartyme’ and other crabapples. The aim was to explore the phenotypic characteristics of half-sib offspring and the effectiveness of breeding.【Method】Based on the weighted hierarchical analysis method(AHP), a comprehensive evaluation system for the ornamental value of crabapple offspring was established from four phenotypic dimensions, namely fruit, flower, tree form and leaf. The focus was on clarifying the characteristics of the offspring in terms of fruit color and phenology.【Result】(1) According to the fruit color at the ripening stage, the fruit colors of 100 single plants of the offspring at maturity can be divided into three categories and nine sub-categories.There are significant differences in the ornamental value of fruit colors at maturity among crabapple offspring of different colors/sub-colors series. (2) Compared with the mother population plants, the fruit fruiting period of the offspring population was relatively longer, and the proportion of late and very late-ripening type was significantly increased. According to the length of the fruiting period and the early and late ripening period of the fruit, the progeny population can be divided into five cultivar groups. (3) Based on the AHP comprehensive evaluation model, the progeny plants were classified into four grades. From grade Ⅰ to Ⅳ, the comprehensive ornamental properties of the progeny plants gradually weakened, superior individuals of grade Ⅰ, such as G45, G71, G70, etc., had bright fruit colors, a large fruit set, and a long fruiting period; although the two, G16 and G85, had relatively low comprehensive scores were very late-ripening, with a long fruiting period of 258 days and prominent single character traits, which made them exhibiting good for ornamental effects.【Conclusion】Through free pollination, the genetic base of the offspring population of half-sibling family lines can be effectively expanded, and the germplasm diversity can be significantly improved.The evaluation system constructed by AHP is more accurate, and can be used for the selection of new varieties of ornamental crabapple and the broadening of the ornamental value of crabapple.