DCPTA和DTA-6对大豆叶片光合及叶绿素荧光特性的调控

Regulation of DCPTA and DTA-6 on Photosynthesis and Chlorophyll Fluorescence Parameters of Soybean Leaves

叔胺类活性物质是一类具有高生物活性和低分子量特性的生物活性物质,其中DCPTA和DTA-6是该类化合物的典型代表。目前有关叔胺类活性物质的研究仅在生理效应上,未能揭示叔胺类活性物质对作物生长发育的调控,特别是对光合作用的调控,从而限制了叔胺类活性物质进一步推广应用。以大豆中黄13为材料,在温室和盆栽条件下,研究叶面喷施叔胺类活物质DCPTA和DTA-6对大豆苗期叶片光合特性、光合关键酶以及叶绿素荧光特性的调控机制。结果表明:DCPTA和DTA-6处理提高了大豆叶片光合速率、蒸腾速率、气孔导度和叶绿素含量,降低了细胞间隙CO2浓度和叶绿素a/b值;提高了PEPC羧化酶和RuBP羧化酶活性;提高了大豆叶片PSⅡ最大光化学效率(Fv/Fm)、PSⅡ有效电子产量(ΦPSⅡ)和光化学淬灭(qP),降低了非光化学淬灭系数(qN);提高了大豆株高和生物量;DCPTA和DTA-6处理的适宜浓度分别为20 mg.L-1和10 mg.L-1。

Tertiary Amines substance is a kind of high bioactive regulators with low molecular weight. DTA-6 and DCPTA are the two representative tertiary compounds,which has various influences on physiological process in plants. Up to now, most work were focused the physiological effect and little has been known about the mechanism of the promotive effect of DTA-6 on plant photosynthesis, which prevent them into practical application. The objective of this work was to find the photosynthetic responses of corn and soybean to foliar application of DTA-6. The effect of DCPTA and DTA-6 on photosynthesis, photosynthetic key enzyme and chlorophyll fluorescence parameters of soybean （cv. Zhonghuang 13） leaves, was studied in pots under greenhouse. DCPTA and DTA-6 were sprayed on leaves at seedling about the first fully explanted leaves, and with water spraying as control. The results mdicated the height and biomass were significantly increased by DCPTA and DTA-6. The photosynthetic rate, transpiration rate, stomatal conductance and chlorophyn content were increased, and the intercellular CO2 concentration and chlorophyll a/b were decreased by the application of DCPTA and DTA-6. The activities of PEPCase and RuBPcase, maximal photochemical efficiency of PS Ⅱ （Fv/Fm）, effective quantum yield of PS Ⅱ （ ФPS Ⅱ ）, photochemical quenching coefficient （qP） were significantly promoted by the application of DCPTA and DTA-6, but non-photochemical quenching coefficient（qN） was declined. The optimum concentration for soybean was 20 mg·L^-1 DCPTA and 10 mg·L^-1 DTA - 6.