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The head of cabbage is vulnerable to crack in the later stage of vegetative growth.Quality of appearance,yield and storability were seriously affected by this.The identification of resistance to head splitting in new germplasm resources and varieties has become a priority in cabbage breeding programs.36 spring and 38 autumn cultivars were investigated under natural conditions for their characters of splitting resistance,and 15 of them were identified with indoor head soak method.The head splitting resistance was assessed by rating the number of split layer and S(the proportion of split size on the whole surface area)on a scale of 0-5.Cracking grades were evaluated as follows: 0,no split; 1,1 split layer; 2,2 split layers and S﹤50; 3,3-5 split layers and S﹤50,or 2 split layers and S≥50; 4,6-10 split layers and S﹤50,or 3-5 split layers and S≥ 50; 5,more than 10 split layers or 6-10 split layers and S≥50.The head splitting index =(Σ(Each grade × Number of heads graded)/the total head number × 5)× 100.The results indicated that the head splitting index of postharvest-5 days for spring cabbage and 15 days for autumn after mature can be used to accurately identify the head-splitting resistance of cabbage,and the head splitting index after 4 hours by indoor soak method can also be used to identify head splitting resistance of cabbage.Cracking resistance evaluation was divided into 5 levels by head splitting index: High Resistance,Resistance,Middle Resistance,Susceptibility and High Susceptibility.The study developed a set of identification methods and standards for selection of splitting resistance cabbage,providing the theoretic basis for selection of splitting tolerant materials and development of new varieties.