Present Situation Of Apple-pear And Studied On Its Resistance Physiology In Yanbian

The experiment determined the cold resistance of pear cultivars' shoots with the method of electric conductance, which based on the biologic membrane theory. The changes in water stadus, cell membrane permeability, the relationship between bound water:free water ratio and cold resistance , the soluble sugar and proline content on five pear species with different cold resistance during the dormancy period were studied. The result showed that the relative electric conductance and injury ratio with temperature represented linearity correlation, the coefficient of correlation represented highest significance; the bound water:free water ratio in some hardier species was beyond 1.0,whereas that in the less hardy species was below 1.0. the contents of soluble sugar and proline increase gradually as the temperature reduces. The soluble sugar content is more in the variety, which has high hardiness and obviously positive correlation with hardiness, but the proline content has no obvious correlation with hardiness.