耐高土壤pH值蓝莓的生长评价与种质筛选

[Objective]Blueberry,the"king of berries",is born in acidic soil(pH 4.5-5.5),and most of the agricultural soils in China have a higher pH than that required for the growth of blueberries,so soil pH is a key factor limiting the growth of cultivated blueberries.By exploring the growth and physi ological characteristics of seedlings of different blueberry varieties under high soil pH environment,we s creened out the blueberry germplasm with high soil pH growth potential,and provided theoretical referen ces and technical services for the selection and breeding of new blueberry varieties with high soil pH to lerance and blueberry cultivation and production.[Method]One year old seedlings of 15 blueberry cultiv ars/lines,including rabbiteye blueberry('Powderblue','Gardenblue','Britewell','Baldwin','Briteblue','Pl olific'),southern highbush blueberry('Zhaixuan 7','Zhaixuan 9','Primadonna','Anna','Sharpblue')and northern highbush blueberry('Legacy','Emerald','Bluegold','Chandler'),which were independently sele cted and bred by our research group and popularized in Jiangsu,were used as test materials,and five so il pH environments[5.0(CK),6.0,6.5,7.0 and 7.5]were set up for potting comparative experiments thr ough external application of CaCO3.The growth and physiological indexes of different blueberry cultivars/lines were observed and measured under each treatment to evaluate their ability to tolerate high soil pH,and key evaluation and identification indexes were screened out.[Result]It was found that high soil p H inhibited the phenotypic growth of blueberry plants,and most of the blueberry cultivars/lines showed"green deficiency"in leaves at soil pH higher than 6.5,and the relative chlorophyll content(SPAD),net photosynthetic rate(Pn),transpiration rate(E),and stomatal conductance(Gs)of 15 blueberry cultivars/li nes were significantly reduced in the pH 7.5 treatment compared with the CK treatment;meanwhile,the plant height and crown width of the 15 blueberry cultivars/lines decreased with the increase of soil pH,and their changes were greatly affected by soil pH,while the changes in the number of ground stems a nd branching were smaller under different soil pH treatments;moreover,the contents of MDA,soluble s ugars(SS)and soluble proteins(SP)were significantly elevated,the activity of antioxidant enzyme CAT was enhanced,and the activity of SOD was decreased in the leaves of the different blueberry cultivars/li nes under the high soil pH treatments,and the relative expression of the relevant enzyme genes,SOD a nd CAT,also showed similar changes.[Conclusion]Among the 15 blueberry cultivars/lines,'Briteblue','Zhaixuan 9','Zhaixuan 7'and'Emerald'showed good adaptability to high soil pH;plant height,SS,le af length,SPAD,E and SOD can be used as indicators for screening the ability of blueberries to tolerat e high soil pH.