Study On The Overwintering Ability Of The New Grape Strain ’Lonzibao’

Grape is a kind of common fruit tree with high economic benefit in north ofChina. However, due to the lower temperature in the North, soil buring winterprotection measures need to be done for most varieties, which increase the cost.Hence, it is necessary to breed a new variety with cold resistance, which is beneficialfor the development of grape industry and germplasm resources. In this study,overwintering performance identification, anatomical observation and physiologicalindexes test was performance within six varieties of grape. The conclusions we havedrawn as following:1.‘Longzibao’ had the best cold resistance and drought resistance, and it couldoverwintering without soil buring winter protection.2. Semilethal temperature caculated by electrolyte osmotic rate and LogisticEquation could effectively evaluated the cold resistance of grape, the resultof which was stable reliable.3. Cold hardiness was affected by the root number, root length and rootdistribution depth. Grape variety with stronger overwintering performancehad developed root system.4. The water retaining capacity of branch in stronger cold hardiness grapevariety was significantly greater than the weaker one, which resulted thatstrong overwintering ability grape variety could overwintering without soilburing winter protection.5. In the grape variety with stronger overwintering performance, branch androot cells were arranged densely, big ratio of bast/xylem,vessel elementswere have low density and big-inch.6. With the temperature decreasing, the content of soluble sugar, soluble protein,free proline and MDA in the branches and roots of different grape varietiesincreased with different extent. Cold hardiness positively correlated with theontent of soluble sugar, soluble protein and free proline, and negativelycorrelated with the content of MDA.