NaHSO3对苹果光合作用和叶绿素荧光的影响
Effects of NaHSO3 on Photosynthesis and Chlorophyll Fluorescence in Apple

以2 a生嘎啦苹果植株为试材，研究叶面喷施不同浓度（0、0.5、1.0、2.0、5.0、10.0 mmol·L-1）NaHSO3后植株的光合作用。结果表明，浓度为0.5～10.0 mmol·L-1的NaHSO3对植株有光合促进作用，浓度为1.0 mmol·L-1效果最好，并可维持12 d。与对照（H2O）相比，经浓度1.0 mmol·L-1 NaHSO3处理后，叶片光系统Ⅱ的最大光化学效率（Fv/Fm）、光适应下光化学效率（Fv′/Fm′）及实际量子产量（ΦPSⅡ）均显著升高。光响应曲线初始斜率（a）、半饱和光强（Ik）及最大电子传递速率（ETRmax）显著升高，光系统Ⅰ的相对含量和活性也明显增大。综合分析认为，低浓度NaHSO3可通过增强电子传递和光系统Ⅰ环式光合磷酸化来促进叶片的光合效能，减轻光合机构在高光强下的光损伤。
Taking two-year-old Gala apple trees (Malus pumila) as material， we studied its photosynthesis after spraying different concentration of NaHSO3 solutions on the leaves .The results showed that concentration of 0.5-10.0 mmol·L-1 NaHSO3 enhanced net photosynthetic rate of which treatment of 1.0 mmol·L-1 NaHSO3 solution had the best effectiveness for 12 days. Under treatment of 1.0 mmol·L-1 NaHSO3 solution, potential photochemical efficiency of photosystem II (Fv/Fm), photochemical efficiency of photosystem Ⅱ under light (Fv′/Fm′) and quantum yield of PSⅡ (ΦPSⅡ) were significantly increased compared with CK. Meanwhile a (initial slope rate, reflecting efficiency of light utilization of leaves) of light response curve,IK(reflecting tolerant ability under strong light), and ETRmax(most electron transport rate) markedly increased. The values of ΔVIP (reflecting the content and activity of PSⅠ) from chlorophyll a fluorescence increased. Based on analysis of the results, low concentration of NaHSO3 solutions can promote photosynthetic efficiency in apple leaves by increasing stimulation of electron transport and cyclic photophosphorylation of photosystem Ⅰ (PSⅠ)of Pn,photodamage of photosynthetic apparatus was substantially alleviated by the application of low concentration NaHSO3 in apple plants under strong light condition.