育种园里的果树开始结果以后,根据与区域规划品种相比较的主要经济性状来进行优良类型的选择;还要根据优良的经济特性和特征最大总和来进行优良类型的选择。 核桃对冬季低温的抗性程度取决于枝条旺盛生长的开始,从树冠不同部分的整个损害已看得出来。根据下面等级表的分级来评? After the fruit trees in the breeding garden start their results, good type selection is based on the main economic traits compared to the regional plan varieties; good type selection is also based on the finest economic characteristics and maximum sum of features. The degree of resistance of walnuts to low temperatures in winter depends on the beginning of the vigorous growth of shoots, as evidenced by the entire damage from different parts of the crown. According to the following rating scale to rating?