持续高温胁迫对茄子幼苗几个主要生理指标的影响

为了明确持续高温胁迫对不同耐热性茄子品种(系)主要生理指标影响的异同,特采用7份耐热性不同的茄子材料,分别进行2、4、6 d高温处理及6 d高温处理后恢复处理,未高温处理苗做对照,研究了高温胁迫对SOD和POD抗氧化酶活性、AsA和GSH含量,MDA和可溶性蛋白含量以及O.-2产生速率、H2O2含量的影响。结果表明:高温处理2 d和4 d时,SOD和POD抗氧化酶活性、AsA和GSH含量增加,相应的O.-2产生速率、H2O2含量下降;6 d时SOD活性、AsA和GSH含量有所降低,O.-2产生速率、H2O2含量上升,POD活性在热敏感品种(系)继续大幅增加。随高温胁迫时间延长MDA含量不断增加,可溶性蛋白含量变化不大。另外,对各生理指标与热害指数和膜相对电导率的相关性分析结果表明,热胁迫6 d时AsA含量及热胁迫2 d时的O.-2产生速率、H2O2含量与热害指数和相对电导率相关显著,可以作为鉴定不同品种耐热性的参考指标。

Effects of Continuous Heat Stress on Several Physiological Indexes of Eggplant Seedlings

Eggplant(Solanum melongena L.)is an important vegetable crop that belongs to the genus Solanum of the Solanaceae family. The aims of this study were to clarify the effects of continuous heat stress on the main physiological indices of eggplants with different heat-resistant and to screen physiological indicators for identification of heat-resistant. Under high temperature stress, seven accessions of eggplant with different heat-resistant were used to study the changes of the antioxidant enzymes SOD and POD, contents of AsA ,GSH, MDA and soluble protein , the production rate of O2 .- , , and content of H2O2. The materials were treated for 2 d, 4 d, 6 d with high temperature, respectively, and 6 d with high temperature then restoration cultivated at normal temperature, not heat-treated seedlings as control. The results showed that: when treated with high temperature for 2 d and 4 d, activities of SOD and POD, and contents of AsA and GSH increased, which corresponded with decreace of O2 .- production rate and H2O2 content. As for 6d the result was that activities of SOD and contents of AsA and GSH decreased, and O2 .- production rate and H2O2 content decreaced, and POD activity continue to increase significantly in heat-sensitive accessions . With the heat stress prolonging MDA content increased, while soluble protein content changed little. In addition, corelations of 8 physiological indicators with heat injury index and electrical conductivity were analysed, respectively. The results were showed that the AsA contents under 6d high temperature and O2 .- production rate and H2O2 contents under 2 d high temperature were significantly related with heat injury index and electrical conductivity, and these 3 physiological indicators could be used as the indicators of identifying heat tolerance of different eggplant materials.