Study On Charcteristics Of Drought Tolerance And Evaluation Methods Of Flax In Key Growth Stage

In order to ascertain change rules of flax’s ecological physiology indexes underdrought stress, and build up drought resistance index evaluation system, with15flaxvarieties as experimental material,under normal irrigation and culture condition ofnatural rainfall, the study puts drought stress to flax at different periods and contributerules of ecological indexes and drought resistance identiication indexes. This searchcan provide scietific theoretical basis and practical reference to drought resistancebreeding and identification of flax,also screening indicators.1. Under the treatment condition of natural rainfall, it has different changes incomparing with plant height, root length, leaf area index, fresh and dry weight ofshoot and root. Variance analysis shows that between the15varieties of flax differsignificantly in plant height, and highly significantly in fresh and dry weight of shootand root, and the difference of root length and leaf area index were not significant.2. Under the treatment condition of natural rainfall, it has different changes incomparing with physiobiochemic of flax’s chlorophylla, chlorophyllb, totalchlorophyll, malonaldehyde, membrane permeability, CAT, SOD, POD and irrigationtreatment. Variance analysis shows that between the15varieties of flax differsignificantly in chlorophyll a, chlorophyll b, total chlorophyll, malonaldehyde,membrane permeability, CAT, SOD and POD.3. Using correlation analysis、 drought-resistant coefficient and drought indexevaluation method to analyze the relationship of flax’s agronomic trait and droughtresistance and to estimate the experimental varieties’ drought resistance. The resultshows that: flax’s agronomic trait has differences in performance under the conditionof natural rainfall irrigation and cultivation, between the two treatment room havesignificant difference on traits t escept effective branch order.4, the drought resistant in all15varieties were divided in5groups which are:2varieties belonging to the "good",4varieties belonging to the "acceptable",6varietiesbelonging to the "moderate" and the other3varieties belonging to the "poor" or "verypoor". According the result, we suggest that selecting higher yield and good qualityflax varieties should improved the production of single plant and1000-grain weightthat as the main appeals, and also pay attention to the traits of more fruit and higherplant.5. The flax area parameter, chlorophylla, chlorophyllb, total chlorophyll, plant height, root length, membrane permeability, POD et al., could serve as the criteria ofdrought resisting for the flax. By treating the flax drought resisting parameter asdependent variable and the absolute value of every individual index as independentvariable, stepwise regression analysis could be used to define the The optimalregression equation as y=1.394+0.016X1+0.303X2-0.881X3-0.286X4. In which, theX1、X2、X3、X4stand for CAT, chlorophyll a, plant height, relative value of plant dryweitht, equation defining parameter R2=0.856. The equation shows a nice mathing.