Study On The Introduction And Growth Adaptability Of Two Cultivars Of Raspberry In Tianjin

The subjects of this study are‘Quping’and‘Heritage’,two varieties of red raspberry,which were planted in three kinds of soil in Tianjin.By studying their phenology,growth,photosynthetic characteristics,and stress resistance（mainly referring to salt-alkali stress）,fruit quality and active substances of the leaf,we can evaluate their adaptability to provide theoretical basis for scientific cultivation and promotion under different environments in Tianjin.The following are our conclusions:1.Most of the information of‘Qiuping’and‘Heritage’was similar,but there were some slight differences with their own characteristics.Their growing periods were close,at least235 days,up to 256 days.The germination stages of all the experimental field were similar,but the resting stages of the experimental site Xiqing2 and Jizhou were earlier than that of site Xiqing1.2.In the three experimental fields,‘Qiuping’and‘Heritage’could adapt to different environments and grow normally.But their phenological periods varied with the experimental field with a strong adaptability.Of the three test sites,those planted in site Xiqing1germinated earliest,on 25 March.While,those in the other two germinated several days later differently.The phenological periods of‘Qiuping’in different sites enjoyed a higher similarity than those of‘Heritage’,and their reproductive phenological periods lasted 30 days.Under good growth conditions,the number of the flowers on the base growing branch of‘Qiuping’and‘Heritage’varied greatly,which was one of their inherent characteristics.The average number of flowers on each branch of‘Qiuping’was 52-70,and that of‘Heritage’was 108-180.The fruit-bearing rates of these two cultivars were higher than 90%,with no physiological fruit drop.In terms of the weight and the horizontal and vertical diameter of the single fruit,while to compare these two cultivars,‘Qiuping’was larger.The yield of each primocane‘Qiuping’was 111-164g,‘Heritage’reaching 154-393g,3.In the aspect of photosynthetic characteristics,the photosynthesis of the 2 varieties was mainly in the morning,but the performances were different.The monthly changes of’Qiuping’showed that the changes in site Xiqing1 and Jizhou were close,but the waterlogging in site Xiqing1 in September caused the decrease of net photosynthetic rate,intercellular carbon dioxide concentration and stomatal conductance,and they recovered in October after the stress was relieved.Inheritance’showed similar changes in March,with July and September as the two peak periods of net photosynthetic rate,and the net photosynthetic rate in site Xiqing2 was the highest from June to September,which could confirm the large growth of’Heritage’in the second half of the year.The diurnal variation of’Qiuping’in July was different from that in site Xiqing1 and site Jizhou,which was limited by soil moisture.In August,the net photosynthetic rate of three plots changed in the same way,but it was obviously restricted by stomatal at 14 o’clock in the afternoon of site Xiqing1;The changes of net photosynthetic rate in site Xiqing2 and Jizhou were similar in September,and the net photosynthetic rate in site Xiqing1 was the lowest in each period.Inheritance’had the highest average value of all-day net photosynthetic rate from July to September,and the daily change analysis showed that obvious stomatal limitation appeared in site Xiqing1 from July to August14,and the intercellular carbon dioxide concentration in site Xiqing2 was the lowest throughout the day,indicating that site Xiqing2 had the most vigorous photosynthesis.The diurnal variation of net photosynthetic rate was consistent among the three plots in September.The stomatal conductance degree days in site Xiqing1 were the lowest,and the daily average value of intercellular carbon dioxide concentration was the highest,which also proved the existence of waterlogging damage.4.Under the single salt stress of NaCl and NaHCO₃,the number of leaves shedding first decreased and then increased with the increase of concentration.In terms of photosynthetic characteristics,low concentration promoted high inhibition.In terms of physiological indexes,’Qiuping’mainly had CAT activity,soluble protein and proline concentration significantly increased to resist damage.When NaHCO₃concentration reached more than 120mmol/L,the soluble sugar content also significantly increased.The activities of SOD and POD were not significantly changed,and malondialdehyde was intermittent accumulated.These three indexes were not suitable to evaluate the stress degree of’Qiuping’.Death occurred when the concentration of NaCl reached 180mmol/L,but no death occurred under NaHCO₃stress,indicating that the resistance to NaCl was not as strong as the resistance to NaHCO₃.5.In terms of the active substances of the leaf,the content of total phenolic,total flavonoid and ellagic acid in leaves of two varieties was the highest in the site Jizhou,’Qiu Ping’reached 76.34mg/g,10.34mg/g,and 1.49mg/g,and’Heritage’reached 78.21mg/g,9.68mg/g,and 1.80mg/g.The collection amount of leaves in each area was determined by the growth amount.Therefore,the two varieties tested in site Xiqing1 had high growth amount and were more suitable for leaf collection.6.In the aspect of fruit quality,in terms of single fruit weight,the fruit in autumn was larger than that in summer,and the soluble solid content of’Qiuping’was higher in summer and soluble solid content of’Heritage’was higher in autumn.The total phenols and total flavonoids of’Qiuping’reached 3.09mg/g and 0.32mg/g in autumn fruit in experimental site Jizhou,which were significantly higher than those in other plots and seasons.The total phenol content of’Heritage’in autumn fruits of site Xiqing2 was the highest,reaching 7.32 mg/g.The average total flavonoids content in site Jizhou was the highest,which was positively correlated with the elevation increase.The Vc content of’Qiuping’was 625–745μg/g and that of’Heritage’was 629–847μg/g,so the total antioxidant activity of’Qiuping’was better than that of’Heritage’.The content of ellagic acid in autumn fruits of the two varieties was higher,the average content of’Qiuping’was higher as 157.8mg/g,and the content of’Heritage’had a significant difference between seasons.