锌对青花菜叶片光合特性的影响

Effects of Zinc on photosynthetic characteristics in leaves of Brassica oleracea L.Vat Italicap

采用砂培的方法,利用气体交换测定技术,研究适量施锌对青花菜叶片光合特性的影响,揭示锌提高青花菜光合能力的生理机制.结果表明:适量施锌较不施锌叶片的叶绿素a和叶绿素b质量分数分别提高8.72%,10.17%,碳酸酐酶(CA)活性提高152.94%;净光合速率(P_n)提高14.32@,气孔导度(G_s)增大41.55@,胞间CO_2浓度(C_i)增加26.17%;表观量子效率(AQY)提高12.14%,羧化效率(CE)提高7.59%.锌通过增大叶片的气孔导度,增加胞间CO_2浓度,降低气孔限制来提高净光合速率;通过提高CA活性来提高叶片的羧化能力和光合能力.

The effects of zinc on photosynthetic characteristics in leaves of Brassica oleracea L. Vat Italicap were studied with the gas exchange technique, in order to understand the mechanism of improvement of photosynthetic capacity with the application of zinc. The results showed that, compared with the control plants, the content of ehla and chlb increased by 8.72%, 10.17% respectively, and CA （carbonic anhydrase） activity increased by 152.94% in Brassica deracea L. Vat Italicap leaves treated by adding 0.5 mg/L Zn^2＋. The Pn, Gs and Ci were higher in leaves treated by adding 0.5 mg/L Zn^2＋ than in leaves of control plants. AQY（apparent quantmn yield） increased by 12.14%, CE（carboxylation efficiency） by 7.05% in leaves treated by adding 0.5 mg/L Zn^2＋, compared with that in control leaves. It was proposed that zinc could decrease stomatal limitation of photosynthesis in Brassica oleracea L. Vat Italicap leaves and improve the photosynthetic capacity by increasing CA activity.