外源亚精胺对淹水条件下玉米物质积累和光合能力的影响

研究淹水对玉米物质积累和光合能力的影响及有效缓解措施,以期为玉米抗逆高产栽培提供依据。以两个耐涝性不同的玉米自交系为试验材料,研究了外源亚精胺对淹水条件下植株物质积累、叶面积、叶绿素含量、净光合速率和叶绿素荧光特性等指标的影响。结果表明,与对照相比,淹水处理显著降低玉米地下部干重、地上部干重、单株干重、相对干物质积累速率和叶面积;随淹水处理天数增加,叶片叶绿素含量、净光合速率和实际光化学效率逐渐降低,且敏感型Su95-1各指标降幅最大。淹水条件下外施亚精胺处理植株,干物质积累量和光合指标较对照显著降低,但较淹水处理有不同程度地提高,且Su95-1增幅更大。综上,在淹水条件下,外施亚精胺能提高叶片的光合能力并提高植株耐涝性,最终增加干物质积累。

Exogenous Spermidine: Effect on Biomass Accumulation and Photosynthetic Capacity of Maize Plants Under Waterlogging Stress

The effects of waterlogging on the biomass accumulation (BA) and photosynthetic capacity of maize and the effective relief measures were studied to provide a basis for the stress-resistant and high-yield cultivation of maize. Two maize inbred lines with different waterlogging tolerance were chosen to study the effect of exogenous spermidine on BA, leaf area, leaf chlorophyll content, net photosynthetic rate and chlorophyll fluorescence characteristics of maize under waterlogging stress. The results showed that compared to the control, the waterlogging treatment significantly reduced the maize biomass of root, shoot and plant, and leaf area, as well as the relative biomass accumulation rate. Along with the increase of waterlogging days, the chlorophyll content, net photosynthetic rate and actual photochemical efficiency gradually decreased, and the decline of Su95-1 (sensitive type) was the most obvious. Compared to those of the control, the BA and photosynthetic characteristics of the waterlogging treated plants with exogenous spermidine application significantly decreased, but they were higher than those in the waterlogging treatment, and the Su95-1 had a great increase. In summary, under waterlogging stress, exogenous spermidine can enhance the photosynthetic capacity and improve waterlogging tolerance of maize plants, and then increase the biomass accumulation.