Study On Cold Resistance And Selecting Indexes Evaluation System Of Winter Turnip Rape (Brassica Campestris L.)

The research was about the ecological adaptation and cold resistance mechanism of winterturnip rape winter turnip rape（Brassica campestris L.）in Northwest China from some indexes,including over-wintering rate, botanical characteristics, physiological and biochemicalcharacteristics, growth and development characteristics and agronomic traits of winter turnip rapevarieties planting in different eco-regions. The relation was studied between Apps and cold resistance ofwinter turnip rape,established the evaluation model on cold resistance. The results were as follows;1.The results showed, with winter turnip rape ecological adaptation from Tian shui to Yongdeng, the over-wintering rate of winter turnip rape reduced, the root collar diameter and root lengthof strong cold varieties were significantly higher than the weak cold varieties, most ofphotosynthetic products were assigned to the roots to supply the growth and storage of winter turniprape in order to survive safely the winter. The growth and development period of winter turnip rapedelay, the time used to vegetative growth is considerably reduced, over-wintering time was doubled,the plant height and branch length were shortened, and the dry matter weight of northern-extendedwinter turnip rape was also decreased, the1000-grain weight and the seeds pee riliqua were higher atYongdeng than at Tianshui.2.The results showed, the cold resistance and the winterness species of winter turnip rape wereclosely related, the winterness species and the vernalization rate of winter turnip rape were closelyrelated, the vernalization rate of Strong winterness varieties is far lower than the weak winterness varietiesplanting in spring significant,.the significant correlation was presented between vernalization rate andmajor climatic and environmental factors. the plant heigh, branch length and main inflorescence lengthwere increased, siliques number was reduced, the1000-grain weight and the seeds pee riliqua werelower. the related indicators of strong winter turnip rape varieties reduced amplitude, the stems andleaves of winter turnip rape varieties planting in spring grew well, the nutrients were allocated toleaves and growthreproductive growth. leaf photosynthetic rate of planting in spring is lower thanplanting in autumn, with the advancement of reproductive growth, the photosynthetic rateincreased.3.The paper was to study the cold resistance of winter brassica rapeseed by botanicalcharacteristics, photosynthetic properties, physiological characteristics, growth and developmentet.al, then evaluated the relationship between the indexes and cold resistance, established the evaluation model on cold resistance, According to indexes, classified the cold resistance of brassicawinter turnip rape. To analyze the cold resistance build the evaluation model and achieveclassification results of cold resistance by variance analysis, regression analysis and cluster analysis.To sow11different cold resistant winter turnip rapes sowing in autumn and in spring, in foureco-regions. the paper observed botanical characteristics during seeding, determined photosyntheticproperties of leaves and physiologic index, root diameter and root fresh weight. calculated overwintering rate comparison of11winter turnip rapes sowing in autumn and the status of growth anddevelopment sowing in spring, in different eco-regions. There are many Significant differences fordifferent varieties in over wintering rate,growth habit,Pore morphology, photosynthetic properties,physiological characteristics, growth and development sowing in spring. A positive correlation waspresented between over wintering rate of winter turnip rapes (y) and increase fo root diameter (x1)，increase of root fresh weight（x2), changes of CAT activity (X3)., changes of POD activity (X4),changes of SP content (x5). A negative correlation was presented between over wintering rate ofwinter turnip rapes (y) and vernalization rate of winter turnip rape sowing in spring (x6),6indexeswere chose by regression analysis to build mathematical evaluation model. I.e.,to built the standardized ridge regression equation,y=0.0084x1+0.1183x2+0.1139x3+0.2041x4+0.1798x5-0.2647x6,achieve no standardized ridge regression equation,y=31.8325+0.2019x1+1.7336x2+2.5561x3+0.8897x4+1.5617x5-0.2864x6(R2=0.8776).the11different cold resistant winter turnip rapes varieties were divided into five kinds bycluster analysis, ultra strong,strong,good,weak,no4.The results showed, low exercise and stress were the main way of the winter turnip rape adopt tothe environment the cold and arid region in northwest China, with low temperature induction, the apoplastproteins appeared APPs, and APPs content increased greatly, after recover some days, APPs contentdecreased or even disappeared,. APPs had ice modification and recrystallization inhibition effect, sothat the hardiness improved of winter turnip rape.