Effects Of Different Rootstocks On Saline-alkali Resistance And Fruit Quality Of ‘Shine Muscat’ Grapes

Objective:To analyze the effects of different rootstocks on the saline-alkali resistance and fruit quality of‘Shine Muscat’grape,and provide theoretical basis for the saline-alkali resistance cultivation and the use of excellent rootstocks of‘Shine Muscat’grape in saline-alkali soil.Methods:In the aspect of saline-alkali resistance,select 1 year old‘3309C’,‘5BB’and‘Summer Black’as rootstocks for grafting with‘Shine Muscat’（SM）,and take‘SM’self-rooted seedlings as control.After 60days of seedling cultivation,irrigate 100 mmol·L^-1Na Cl+Na HCO₃（1:1 mixture according to the amount of substances）complex saline solution（p H8.2）,and irrigate it with a concentration of 50 mmol·L^-1every day,and reach the set concentration after two days,Start to calculate the stress time,and take samples on the 0th,10th,20th and 30th days of stress treatment to measure the plant growth,leaf water content,relative chlorophyll content,photosynthetic parameters,chlorophyll fluorescence parameters,POD activity,SOD activity and MDA content.The principal component analysis,correlation analysis and membership function analysis are used for comprehensive evaluation.In terms of fruit quality,the 3-year-old‘3309C’,‘Kangzhen No.3’and‘Summer Black’were selected as rootstocks and grafted with‘Shine Muscat’（SM）,and the self-rooted seedlings of‘Shine Muscat’were used as the control.The indexes such as ear weight,grain weight,vertical and horizontal diameter,color,soluble solids content,titratable acid content,hardness,Vc content,aroma substance type and relative content of fruit were measured,The effect of different rootstocks on the fruit quality of‘Shine Muscat’grape was comprehensively evaluated with the method of membership function.Results:1.Under 100 mmol·L^-1Na Cl+Na HCO₃compound saline-alkali treatment,with the extension of stress time,the stem diameter growth,internode length growth,leaf water content,relative chlorophyll content,Pn,Gs,Tr,Fv/Fm,Y（Ⅱ）,q P of different rootstocks of‘Shine Muscat’grape showed a downward trend;Ci,NPQ,POD activity,SOD activity and MDA content showed an upward trend;Among them,the variation range of‘SM/Summer Black’was smaller than that of other rootstock and panicle combinations.Under the same stress time,the multiple indicators of‘SM/Summer Black’are better or similar to those of‘Shine Muscat’self-rooted seedlings.Compared with the multiple indexes of‘SM/3309C’and‘SM/5BB’,the self-rooted seedlings of‘Shine Muscat’are worse.2.Different rootstocks have a great impact on the fruit quality of‘Shine Muscat’grape.The ear weight,fruit grain weight and vertical and horizontal diameter of‘SM/Kangzhen No.3’and‘SM/Summer Black’grape are better than those of‘Shine Muscat’self-rooted fruit.Rootstock‘3309C’and‘Summer Black’can significantly improve the fruit color of‘Shine Muscat’grape‘SM/3309C’grape has the largest fruit hardness,which can improve the storage capacity of fruit.There are the most kinds of aroma substances in the fruit of‘Shine Muscat’self-rooted seedlings.The relative content of terpenes in‘SM/Summer Black’fruit is significantly higher than that in self-rooted seedlings.Grafting‘Shine Muscat’grape with‘Summer Black’as rootstock can significantly increase the rose aroma of grapes and improve fruit quality.Conclusion:1.According to the comprehensive score and ranking,the order of saline-alkali resistance of different rootstocks‘Shine Muscat’grape is‘SM/Summer Black’>SM>‘SM/3309C’>‘SM/5BB’.Compared with the self-rooted seedlings of‘Shine Muscat’,‘SM/Summer Black’has stronger saline-alkali resistance,and has certain adaptability to the complex saline-alkali stress of 100 mmol·L^-1Na Cl+Na HCO₃,which can improve the saline-alkali resistance of‘Shine Muscat’grapes and ensure the normal growth and development of grapes.2.The fruit quality of‘Shine Muscat’grape with different rootstocks ranked from best to good as‘SM/Summer Black’>‘SM/Kangzhen No.3’>‘SM/3309C’>SM.Using‘Summer Black’as rootstock in Zhengzhou can significantly improve the fruit quality of‘Shine Muscat’grape.