60Co-γ辐照对高州油茶光合特性的影响

摘要

In order to provide some technical references for germplasm resource innovation and irradiation mutation breeding inCamellia gauchowensis, changes of photosynthetic characteristics and related cell structure were investigated under different doses of60Co-γ ray irradiation. The results showed that the thickness of leaf tissue structure treated within 10-70 Gy had a trend of thickening, but that in 80 Gy treatment didn’t change, even decreased. ThePn value ofC. gauchowensis leaves showed different regulations in different irradiation dose treatments. Irradiation at 10-80 Gy could promote the photosynthesis ofC. gauchowensis, in which it had the strongest ability to use weak light in 20 Gy treatment, and had the strongest ability to use strong light in 60 Gy treatment. Light response curves ofC. gauchowensiswere different in the different irradiation dose treatments, and irradiation signiifcantly inlfuenced light compensation point and dark respiration rate. Irradiation also signiifcantly inlfuence net photosynthetic rate, water use efifciency, photosynthetic utilization efifciency, intercellular CO2 concentration, and the impacts were different in different seasons.%为给高州油茶种质资源创新及辐射诱变育种提供技术参考，研究了在不同剂量60Co-γ射线照射条件下高州油茶的光合特性及与其相关的细胞结构等指标的变化情况。结果表明：经10～70 Gy辐照处理后的高州油茶叶片各组织结构厚度都有增厚的趋势，而以80 Gy辐照处理的叶片各组织结构的厚度均未改变甚至有减小的趋势；不同剂量的辐照处理后高州油茶叶片的Pn值呈现出不同的变化规律，剂量在10～80 Gy内的辐照处理均能促进高州油茶的光合作用，其中以20 Gy辐照处理的高州油茶其利用弱光的能力最强，以60 Gy处理的油茶其利用强光的能力最强；不同剂量辐照处理下高州油茶的光响应曲线之间存在差异，辐照对其光补偿点、暗呼吸速率的影响均显著；不同剂量的辐照处理对高州油茶净光合速率、水分利用效率、光合利用效率、胞间二氧化碳浓度等光合指标均有显著影响，且在不同的季节其影响的程度不同。