Study On Cold Resistance Of Different Varieties(strains) Of Chinese White Olives

Chinese white Olive[Canarium album(Lour.)Raeusch.]is a characteristic fruit which can bring economic profit in Fujian.It has a unique taste,and can use in medicine and for eating.Chinese white Olive can grows well in warm environment,if the temperature goes down,it will lead Chinese white Olive to freezing damage or even to death.Because of that the low temperature has become an environmen-tal factor that restricts the introduction and cultivation which also limits the industrialization development of Chinese white Olive.This research used’Sanlenglan’,’Changying’,’Meiputianlan’ and other Chinese white Olives as test materials to study the resistance to low temperature of Chinese white Olive by measuring the ratio of relative electrolyte leakage under the treatment of different temperatures and durative time,and then combining with Logistic equation to get the semi-lethal temperature(LT50)of Chinese white Olive.In order to study the difference and changes of varieties(strains)of Chinese white Olive’s cold resistance in overwinter-ing period,physiological indexes were measured,such as the content of soluble sugar,hydrogen peroxide,ascorbic acid,the ratio of relative electrolyte leakage and the ratio of bound water to free water,etc.At last,the content of abscisic acid,soluble protein,and related cold resistance indicators of’Yixilan’ ’Makengtianlan’,’Sichuantangyuan’,’Dianbaiertou-jianlan’,’Zilaiyuan’,’Minqing No.2’ and other Chinese white Olives which were introduced from Guangdong,Sichuan,Zhejiang were obtained.Through correlation analysis,principal component analysis,membership function and combined comprehensive evaluation with field survey results,screening out the cold resistance varieties(strains).The above provide theoretical and practical basis for the introduction,cultivation and the expansion of Chinese white Olives cultivated areas.The research results are as follows:1.Under low temperature stress(treatment temperature:CK,1,-1,-3,-5,-7 ℃)obtained the ratio of relative electrolyte leakage in Chinese white Olive leaves.The results were indicated that different duration of low temperature had an effect on the cold resistance of Chinese white Olive.The Chinese white Olive leaves treated at CK,1,-1℃,the ratio of relative electrolyte leakage changed unobviously with the passage of time,at-3,-5,-7℃,the ratio of relative electrolyte leakage was increasing obviously.The another research shows that Chinese white Olive leaves were treated at different temperatures for 12 h,the ratio of relative electrolyte leakage of Chinese white Olive under 1 ℃ treatment changed little compared with CK;and under-3 ℃ treatment,the ratio of relative electrolyte leakage of ’Beixitanxiang’,’Sanlenglan’,’Huiyuan’,’Changying’and ’Meiputianlan’ were 1.62,1.32,1.90,1.35 and 1.43 times as high as the treatment at-1 ℃,compared to-3 ℃.The ratio of relative electrolyte leakage among ’Changying’,’ Meiputianlan ’ and ’Sanlenglan ’ increased largely under-5 ℃ treatment,increasing by 24.47,29.22,19.57%,respectively.And then the ratio of relative electrolyte leakage was fitted to the Logistic equation to obtain the Semilethal temperature(LT50):-2～-4 ℃。2.During over-wintering period,the indexs about cold resistance of Chinese white Olive were changed with the temperature.The activity of protective enzyme(superoxide dismutase,peroxidase,catalase),the content of protective substances(ascorbic acid,glutathione)increased initially and then declined with the decrease of temperature,the order of protective enzyme and protective substances from high to low were’Changying’,’Sanlenglan’,’Huiyuan’,’Meiputianlan’,’Beixi tanxiang’.The content of osmotic adjustment substances(soluble sugar,soluble protein)increased to different degrees during the wintering,and reached the maximum on February 9,2018.Among them,the content of osmotic adjustment substances of ’Beixitanxiang’ and ’Meiputianlan’ were less than ’Huiyuan’,’Sanlinglan’,and ’Changying’ was always higher than others.During wintering the changes of the ratio of bound water to free water was similar to the content of osmotic adjustment substance.The ratio of relative electrolyte leakage and content of malondialdehyde increased continuously and reached the maximum in the later period.The difference and tendency of content of hydrogen peroxide among Chinese white Olives were consistent with the ratio of relative electrolyte leakage.The results showed that as the temperature declined,membrane permeability of plant cells began to increase,the content of membrane lipid peroxide and hydrogen peroxide began to accumulate.The activity of protective enzymes and the content of protective substances increased in plant to protect cells by removing excessive reactive oxygen.However,as the temperature continued to decrease,a large amount of active oxygen produced which inhibited the activity of protective enzymes and the content of protective substances,leading to the decreases in activity of protective enzyme and content of protective substances after overwinter-ing period.The accumulation of osmotic adjustment substances can maintain cell osmotic balance,thereby adapting to the temperature reduction during wintering.3.The related physiological indicators of 23 varieties(strains)of Chinese white Olives were measured.Correlation analysis showed that the content of soluble protein and soluble sugar were significant positive correlation,and had a significant negative correlation with the rate of relative electrolyte leakage.Besides that the content of soluble protein,soluble sugar and the rate of relative electrolyte leakage could be used as the indicators to identify the cold resistance of Chinese white Olive.Though the method of cold resistance comprehensive evaluation,23 varieties(strains)of Chinese white Olives were divided into two categories,the results shows that 7 varieties of Chinese white Olives are the most cold-resistant and the remaining 16 varieties of Chinese white Olives are moderate resistance to cold.The result is consistent with the field survey results.The specific classification results are as follows:The most cold-resistant varieties(strains):’Baishatanxiang’,’Zhejiang-pingyang No.1’,’Jiexixianglan’,’Makengtianlan’,’Lanshan No.1’,’Chang-ying’,’Sanlenglan’;Moderate cold-resistant varieties(strains):’Zilaiyuan’,’Yixilan’,’Hong-yunlan’,’Dianbaiertoujianlan’,’Baishatianlan’,’Huiyuan’,’Meiputianlan’,’Bei xitanxiang’,’Zhenxiang’,’Yongdingxianshiwutian No.3’,’Qilichi’,’Minqing No.2’,’Yongdinghuleishangbei No.1’,’Baiyuanlan’,’DianBaiqingpilan’,’Si-chuantangyuan’.