Identification Of Alkali Tolerance Of Grape Stock Varieties (Lines)

Grape is one of the most important economic fruit trees.At present,China's grape cultivation area has ranked second in the world.Northwest China is the largest grape producing area.However,soil salinization is very serious in this area,which hinders the development of grape industry.China's grape grafting culture started late,and the research on grape rootstock is relatively weak,and it is mainly focused on the breeding and application of cold-resistant rootstock.There is no systematic research on the salinity tolerance of rootstock.In order to meet the needs of the sustainable development of China's grape industry,selecting saline-alkali resistant rootstock and grafting cultivation are of great importance to effectively deal with soil salinization.In this study,the alkali resistance of 26 potted grape rootstock varieties or lines were preliminarily evaluated by irrigating different concentrations of lime water and investigating the yellowing degree of grape leaves.Meantime,the changes of available Ca²⁺,Mg²⁺and Fe²⁺content as well as pH value in soil were determined.On this basis,using the same concentration of 20%lime water to irrigate the plants,the alkali injury index,the content of chlorophyll,MDA and free proline,as well as relative conductivity were determined.Finally,the alkali resistance of 26 grape materials was comprehensively evaluated by the membership function method.The results obtained were as follows:1.Under the alkali stress of lime water irrigation with different concentration,the alkali injury degree of each rootstock variety or lines was quite different.In the same treatment group,there was a significant difference in the leavl of alkali resistance.The yellowing degree of leaves and the beginning time of leave yellowing were different.Among the test meterials,5BB,YT32,YT48,YH39,YH58,SO4 and 110R showed stronger alkali resistance,and Beta,Beichun and Yanshan-1 showed distinct susceptible.For other grape varieties or lines,they presented middle resistance to alkali.2.Under the conditions of lime watering,the contents of available ions of calcium,magnesium and iron in the soil are disordered,and they are not simply increased or decreased but fluctuate.On 42 days after alkali stress,comparison with the control?without alkali stress?,the content of effective calcium ions in soil increased,the content of effective magnesium changed little,the content of effective iron decreased in four alkali concentration?15%,18%,20%,22%?stress but increased with 0.05mg/kg in 10%alkali concentration.3.At the same concentration of 20%lime water stress,the relative?REC?conductivity,the contents of malondialdehyde?MDA?and free proline?PRO?increased in grape leaves;the contents of chlorophyll?Chl?in grape leaves were divided into two different trends,some varieties or strains increased first and then decreased,the remaining varieties or strains were opposite.The different changes of physiological indexes reflect the difference of alkali resistance in grapevines.4.The result of comprehensive evaluation shows that the alkali-resistant level of tested materials can be divided into five types:5BB,YT32,YT48,YH58 belong to High resistance;3309,SO4,225Ru,5C,V.Riparia???,1103P,188-08,V.riparia Mcadams,00-1-5,00-1-10,6-12-4,6-12-6,Heshan-1,YH39 belong to general resistance;110R,101-14,Kangzhen 3,6-12-1 belong to Middle resistance;Beta,Beichun,Red Globe belong to Susceptible;Yanshan-1 belong to High susceptible.