观赏海棠杂交后代萌芽期观察及花期预测的灰色关联度分析

以‘国光’苹果（Malus domestica‘Rails’）为母本，以10个观赏海棠品种（Malus spp．）为父本进行杂交育种，对杂交后代实生群体的萌芽期进行了观察，并根据9株2年即开花单株的童期性状对观赏海棠的花期进行了灰色关联度分析。结果显示，所有观赏海棠杂交后代的萌芽期（3月12日以后）均晚于父本，93．89％的杂交后代萌芽期（3月下旬至4月上旬）与母本相近或稍晚于母本。在观赏海棠杂交后代花期的叶片叶绿素含量、可溶性蛋白质含量、叶面积、株高、地径等指标以及童期的萌芽期和展叶期等7个性状中，萌芽期和展叶期与花期的灰色关联度最大。因此，在童期利用叶片萌芽期对观赏海棠的花期进行预测极具可行性。

Observation of sprouting stage and grey relational degree analysis on flowering stage forecast of hybrid progenies of crabapple (Malus spp.)

The cross breeding of crabapple （Malus spp.） was carried out with Malus domestica ＇Ralls＇ as female parent and ten cultivars of crabapple as male parent. The sprouting stage of hybrid progenies was observed and the grey relational degree analysis on flowering stage and juvenile phase was conducted based on some characters of nine flowering individuals （2 years old） in juvenile phase. The result shows that the sprouting stage （later than 12th March） of all hybrid progenies is later than that of the male parents, and the sprouting stage of 93.89% hybrid progenies （from the last ten days of March to the first ten days of April） is closed to or a little later than that of the female parent. Among the characters of leaf chlorophyll content, soluble protein content in leaf, leaf area, height, ground diameter in flowering stage, and sprouting date and leaf-expansion date in juvenile phase, the relational degree of sprouting date and leaf-expansion date to flowering date is the biggest. Therefore, it is feasibility to use the sprouting date in juvenile phase to predict flowering date of crabapple.