Etermination And Comprehensive Evaluation On Cold Resistance Of Flower Bud Of Almond

The Amygdalus ledebouriana Schlech as a control, the US introduced4varieties (’Nonpareil’、’Mission’、’Butte’、’Thompson’) and4local variety (’yingzui’、’shuangguo’’zhipi’、’shuangruan’)as the test material for the study of flower buds in Xinjiang.In front of the natural overwintering and after overwintering were collected fruiting branches back to the laboratory.Determination on the changes of leakage ratio of electrolyte of the flower buds which were treated under different artificial simulated(-15～-35℃) low temperature.There were the leakage ratio of electrolyte and leaves physiological and indexes. Such as soluble sugar content,soluble protein content,the proline content,MDA content,SOD activity,POD activity and CAT activity. There detected or measured under the cold resistance.Regression model was established by using logistieequation and determination on the semi-lethal temperature.Fally,the application of the subordinate function and principal component analysis method to evaluate the flower bud on cold resistance of almond.The main results were as follows:1. The leakage ratio of electrolyte increased like"S"curve concomitant with temperature reducing.The Amygdalus ledebouriana Schlech was determined that semi-lethal temperature (LT50) was-26.95℃and the US introduced4varieties LT50was (-17.34～-21.3)℃,4local variety (-13.32～-18.44)℃before overwintering. The Amygdalus ledebouriana Schlech was determined that semi-lethal temperature(LT5o) was-26.95℃and the U.S. introduced4varieties LT50was (-15.91～-18.64)℃, five local variety (-11.4～-15.45℃)℃after overwmtenng.2. The result of anova showed:In the front of owerwintering of flower bud, the leakage ratio of electrolyte was highly significant differences under different low-temperature treatment,MDA content,POD activity, CAT activity under different low-temperature treatment of the Amygdalus ledebouriana Schlech and the remaining8varieties were highly significant differences.Proline content,SOD activity and soluble protein content under different low-temperature treatment of the Amygdalus ledebouriana Schlech and the remaining8varieties were no significant differences.Soluble sugar content under different low-temperature treatment of the Amygdalus ledebouriana Schlech and the local4varieties were no significant differences. In the after of owerwintering of flower bud, the leakage ratio of electrolyte was highly significant differences under different low-temperature treatment. MD A content, POD activity, proline content under different low-temperature treatment of the Amygdalus ledebouriana Schlech and the remaining8varieties were highly significant differences.SOD activity,CAT activity under different low-temperature treatment of the Amygdalus ledebouriana Schlech and the local4varieties were no significant differences. Soluble sugar content under different low-temperature treatment of the Amygdalus ledebouriana Schlechand and the’yingzui’、’shuangguo’varieties were highly significant differences.Soluble protein content under different low-temperature treatment of the Amygdalus ledebouriana Schlech and the local4varieties were highly significant differences.3. According to the application of subordinate function method shows that Amygdalus ledebouriana Schlech subordinate function value of0.653, US introduced variety average value of0.501and the local variety averahe value of0.299before owerwintering of flowe bud under different low-temperature treatment.Amygdalus ledebouriana Schlech subordinate function value of0.624. US introduced variety value of0.389and the local variety value of0.313after owerwintering of flowe bud under different low-temperature treatment. Comprehensive evaluation the strength of the cold resistance was:Amygdalus ledebouriana Schlech> US introduced variety>local variety.4. Based on principal component analysis shows that Amygdalus ledebouriana Schlech subordinate function value of1. US introduced variety average value of0.313and the local variety averahe value of-0.419before owerwintering of flowe bud under different low-ternperature treatment. Amygdalus ledebouriana Schlech subordinate function value of1.001、US introduced variety value of0.339and the local variety value of-0.316after owerwintering of flowe bud under different low-temperature treatment. Comprehensive evaluation the strength of the cold resistance was:Amygdalus ledebouriana Schlech> US introduced variety>local variety.