外源6-BA对低温胁迫下茄子幼苗光合作用、叶绿素荧光参数及光能分配的影响

Effects of Exogenous 6-BA on Photosynthesis, Chlorophyll Fluorescence Characteristics and the Allocation of Absorbed Light in Eggplant Seedlings under Low Temperature Stress

本文研究了外源6-BA对低温胁迫下茄子幼苗光合作用、叶绿素荧光参数和能量分配的影响。结果表明,外源6-BA显著增加了低温胁迫下茄子叶绿素含量、净光合速率(P n)、蒸腾速率(T r)、气孔导度(G s)和胞间CO2浓度(C i);同时外源6-BA明显提高了低温胁迫下茄子幼苗叶片的PSII最大光化学效率(F v/F m)、PSII潜在活性(F v/F o)、PSII天线转化效率(F v′F m′)、实际光化学效率(ΦPSII)、光化学猝灭系数(q P)和光化学反应能量(P),降低了非光化学猝灭系数(NPQ)、天线热耗散能量(D),对非光化学反应耗散能量(E)无明显影响。表明外源6-BA处理通过促进低温胁迫下茄子幼苗光合作用,提高光合电子传递效率,从而保护光合系统,降低低温胁迫对植物的损伤。

The effects of exogenous 6-BA on photosynthesis, chlorophyll fluorescence characteristics and the allocation of absorbed light in eggplant seedlings under low temperature stress were investigated. The results showed that 6-BA significantly induced contents of chlorophyll, net photosynthetic rate （Pn）, transpiration rate （Tr）, stomatal conductance （G＋）, and the intercellular CO2 concentration （Ci）. And 6-BA significantly increased photochemical efficiency of photosystem II （Fv/Fm）, potential photochemical efficiency （Fv/Fo）, excitation capture efficiency of open centers （Fv＇Fm＇）, actual photochemical efficiency （vsxt）, photochemical quenching coefficient （qp） and the fraction of photochemical efficiency （P）. However, 6-BA decreased non-photochemical quenching coefficient （NPQ）, the fraction of antenna heat dissipation （D）, while 6-BA had no remarkable effects on excess energy （E）. This then suggests that 6-BA increases photosynthesis, improves photochemical electron transport efficiency, and thereby protected eggplant seedlings against low temperature-induced damages.