玉米不同自交系幼苗光合对UV-B辐射增强的响应

Responses of Maize Seedling Phoposynthesis in Different Inbreed Lines to Enhanced Ultraviolet-B Radiation

为了探讨玉米不同自交系对UV-B辐射增强的响应,在摸拟光照培养条件下,研究了增强UV-B辐射对玉米不同自交系气体交换参数的影响。结果表明,五叶期UV-B辐射处理6 d后,供试的48个自交系中近一半以上材料的幼苗叶片光合速率、气孔导度和蒸腾速率显著降低10%以上,其材料比例分别为64.6%,47.9%,54.2%;而有62.5%的材料胞间CO2浓度表现为显著增加;相关分析发现,气孔导度与蒸腾速率对UV-B辐射增强的响应值间存在极显著正相关关系;根据气体交换参数对UV-B辐射增强的响应程度将48个材料分成6类,其中对增强UV-B辐射反应比较敏感的材料和能够忍耐UV-B辐射增强的材料均占12.5%。说明玉米不同自交系幼苗叶片气体交换参数对UV-B辐射增强反应敏感程度具有显著的基因型差异,从中能够筛选出对UV-B辐射增强反应敏感和有忍耐能力的材料。

To explore responses of maize seedlings in different inbreed lines to enhanced ultraviolet-B radiation,48 inbreed lines were planted in artificial culturing room with 2 treatment groups.One group is the control and another group was treated with enhanced UV-B dose in 57.8 μW/cm2 after 5 leaf stage.Using a portable TPS-2 photosynthetic analysis system,the photosynthetic rate（A）,stomatal conductance（G）,intercellular CO2 concentration（Ci） and transpiration rate（E） were recorded after six days of treatment.Results indicated that in most of test material,the leaf A,G,and E were increased above 10% under UV-B treatment and their percentage in 48 lines were 64.6%,47.9% and 54.2%,respectively.However,leaf E in 62.5% lines was reduced above 10% under UV-B treatment.There is significant correlation between the responses of G and E.The test inbreed lines was divided into six categories based on their performances to UV-B treatment.There were 12.5% inbreed lines with high sensitive and tolerance to enhanced UV-B radiation,respectively.It can be concluded that there is significant genotype difference for the sensitivity of maize inbreed line to enhanced UV-B radiation and the materials with high sensitive or tolerance to enhanced UV-B radiation could be obtained.