Effect of High Temperature Stress on Some Physiological Indexes of Potato Seedlings with Different Maturity

PurposeTo study the heat-resistant mechanism of potato and provide reference for the selection of heat-resistant varieties.

MethodUnder high temperature stress, the phenotypes, some physiological indexes and protective enzyme contents of three potato varieties Yunshu901 (early maturing), Yunshu305 (middle late maturing), Hezuo88 (late maturing) were measured.

ResultThe growth phenotype, SOD activity, POD activity and MDA content of potato seedlings were affected by high temperature stress. The growth phenotype of Yunshu901 was better than that of other varieties; at 37 ℃, the SOD activity of Yunshu901 showed a downward trend with the increase of stress time, while the other varieties showed an increase and then decreased; at 30 ℃, the POD activity of Yunshu901 showed a downward trend with the increase of stress time, and other varieties showed an upward trend; at 23 ℃ and 30 ℃, the MDA content of Yunshu901 decreased significantly at 5^th day, while other varieties did not appear. These results showed that the heat resistance performance of Yunshu901 was better than that of other varieties with later maturity.

ConclusionContinuous high temperature stress affected the growth phenotype, antioxidant enzyme activity and membrane quality of potato seedlings, and the later maturing varieties were greatly affected. The maturing period may be one of the factors for selecting heat-resistant potato varieties.