Relationship Of Major Morphological Characteristics With Low Temperature Tolerance In Savoy

Savoy(Brassica campestris L. ssp. chinensis var. rosularis Tsen)is crucifer canola not knot ball a variety of the cabbage and likes cold cool down.The optimum temperature of seed germination is 20～25℃, the optimum growth temperature is 15～20℃ and ability of 8～10 ℃ low temperature below zero. In recent years, the cultivation area of savoy and open country winter savoy is gradually increasing. Due to lack of the research on its cold resistance system, therefore unable to meet its cultivation needs to winter low temperature regions.The cold resistance of 6 savoy varieties were test materials. The cold comprehensive evaluation of chilling tolerant coefficient (CTC) about the level of relative electric conductivity, semilethal temperature, MDA content, soluble sugar content, free proline content, chlorophyll content and the activities of SOD in leaves of savoy seedlings under low temperature stress (5d)while were evaluated by correlation analysis and cluster analysis. The rest of the seedlings grown in field, waiting for mature determines their 12 morphological characteristics, were evaluated by principal components analysis. Studied relationship of major morphological characteristics with low temperature tolerance in savoy to improve savoy cold resistance identification and screening efficiency, had the advantages of intuitive and convenient, provided reference for breeding and cultivation. The results showed that:1 Low temperature phase physiological and biochemical indexes in seedling stage of savoyThe range of semilethal temperature (LTso) was-0.30--2.17℃.With the reducing of the processing temperature index of the content of free proline content and chlorophyll content were not the extent of change.The change of MOD content each type with different stress time.The content of soluble sugar content, free proline content, chlorophyll content and the activities of SOD in’No. 1 Huiwu’ changed to a larger extent. During low temperature treatment, no significant correlation was found between pigments content with chilling tolerance of savoy various cultivars and soluble sugar content of each type was increased.2 Savoy cold resistance identification index is proposedThe correlation analysis showed that the six physiological indexes were relatively independent,so the cold resistance of savoy cultivars should by measured and evaluated by multiple indexes.By cluster analysis of indexes,relative electric conductivity and relative MDA content were suitable for evaluating cold tolerance.3 Has been clear about savoy main morphological characteristics of indicatorsBy principal component analysis, fallen leaves, leaf area, plant type, degree of compaction is the main reflect the main morphological characteristics of single parameter.4 Has been clear about relationship of major morphological characteristics with low temperature tolerance in savoyLow temperature treatment determination of seedlings, the physiological and biochemical indexes of cold resistance is strong "Huiwu 2", "Huiwu 1","Tadiwu 6", cold tolerance weaker variety is "Tadiwu 3", "Tadiwu 2", "Tadiwu 1". Leaf color depth, small size, small plant type. tight varieties of cold resistance is strong; Leaf color, leaf area, plant type, the variety of loose cold resistance is weak.