Salt Tolerance Comparison Of Different Strawberry Varieties And Effects Of Saline-Alkali Soil On Their Growth And Quality

Soil salinization is a global problem,which seriously threatens the growth and development of plants,and also restricts the development of strawberry industry.The strawberry germplasm resources are abundant in China,and the salt tolerance of the varieties is significantly different.It is very important to identify the salt tolerance of strawberry varieties and to screen salt-tolerant varieties,which is especially important for the development of strawberry industry.Ten strawberry varieties including “Benihoppe”,“Akihime”,“Sachinoka”,“White Strawberry”,“Jing Chunxiang”,“Sweet Charlie”,“Frandy”,“Jiuxiang”,“Space 2008” and “Miaoxiang No.7” were used as test materials to study the effects of NaCl stress(CK,0.2%,0.4% and 0.6%)on the growth,physiological and biochemical indexes of strawberry seedlings;Besides,the growth and fruit quality traits of these different strawberry varieties in saline-alkali soil(soil salinity is 0.36%,pH=8.25)were studied.The purpose of this study is to screen out strawberry varieties that are highly salt tolerant and suitable for saline-alkali cultivation.It provides a theoretical basis for the breeding of strawberry salt-tolerant varieties.The main results are as follows:1.From the characteristics,the salt damage in leaves of “Akihime”,“Sachinoka”,“White Strawberry” and “Benihoppe” strawberries appeared late,and there was no symptoms of salt damage under 0.2%NaCl stress.The degree of salt damage under high salt concentration and long-term stress was also relatively small.The leaves of “Miaoxiang No.7” and “Space 2008” strawberries appeared the earliest and most severely damaged by salt,while other varieties were in the middle.NaCl stress inhibited the growth of plant height,leaf area and biomass accumulation of different strawberry varieties.The increment of plant height,leaf area and biomass of “Miaoxiang No.7” and “Space 2008” were mostly inhibited by salt damage,while those of “Akihime”,“Benihoppe”,“White Strawberry” and “Sachinoka” were slightly inhibited,others were in the middle.2.Under salt stress,“Benihoppe”,“Akihime”,“White Strawberry” and “Sachinoka” had the smallest decrease in relative water content,followed by “Frandy” and “Sweet Charlie”,while “Jiuxiang”,“Space 2008” and “Miaoxiang No.7” had the greatest decline.The relative conductivity and malondialdehyde(MDA)content of “Space 2008” and “Miaoxiang No.7” were higher,and the membrane system was damaged seriously.The membrane system of “Benihoppe”,“Akihime” and “Sachinoka” was the least damaged,and other varieties were in the middle.The content of osmotic adjustment substances such as free proline,soluble sugar and soluble protein increased first and then decreased with the increase of NaCl concentration and the stress time.“Akihime”,“White Strawberry”,“Benihoppe” and “Sachinoka” had the highest accumulation of free proline,soluble sugar and soluble protein under salt stress,whereas “Space 2008”,“Miaoxiang No.7” and “Jing Chunxiang” were the least,and other varieties were in between.The chlorophyll content of “Benihoppe”,“Akihime” and “Sachinoka” decreased the least,while “Space 2008” and “Miaoxiang No.7” decreased the most,and other varieties were in the middle.The activities of SOD and POD in leaves first increased and then decreased with the increase of stress time.Among them,“Benihoppe”,“Akihime” and “White Strawberry” were significantly higher than other varieties,while “Space 2008” and “Miaoxiang No.7” were the lowest.3.Principal component analysis was used to analyze the growth,physiological and biochemica indexes of different strawberry varieties under salt stress.The results showed that the salt-tolerant ability was comprehensively sorted as: “Akihime”>“White Strawberry”>“Sachinoka”>“Benihoppe”>“Frandy”>“Sweet Charlie”>“Jiuxiang”>“Jing Chunxiang”>“Space 2008”>“Miaoxiang No.7”.4.The results of comprehensive analysis on the growth status of these different strawberry varieties in saline-alkali soil showed that the four strawberry varieties of “Benihoppe”,“Akihime”,“White Strawberry” and “Sachinoka” grew well in saline-alkali soil,while “Miaoxiang No.7” and “Space 2008” performed poorly,and other varieties showed moderate performance.5.Under the condition of saline-alkali soil,there were significant differences in yield and fruit quality of different strawberry varieties.The four strawberry varieties of “White Strawberry”,“Akihime”,“Benihoppe” and “Sachinoka” had excellent fruit quality and high yield in saline-alkali soil,while “Space 2008”,“Jing Chunxiang” and “Sweet Charlie” had low yield and poor quality traits,and other varieties were in the middle.Comprehensive analysis shows that four strawberry varieties of “Benihoppe”,“Akihime”,“White Strawberry” and “Sachinoka”,have strong salt tolerance,good growth performance,excellent fruit quality and high yield,are suitable for planting and promoting in saline-alkali soil.“Space 2008” and “Miaoxiang No.7” have poor salt tolerance,poor growth performance and low yield,are not recommended for planting in saline-alkali soil.