水分胁迫对不同类型大豆光合特性的影响
Effects of Water Stress on Photosynthetic Characteristics of Different Phenotypic Soybeans

为明确干旱胁迫对不同类型大豆光合特性的影响，选用耐密植品种‘垦丰16’与常规栽培品种‘绥农14’为试材，采用盆栽试验，分别于盛花期（R2）和鼓粒期（R6）进行轻度干旱、重度干旱和常规水分管理（对照）3个水分处理试验，测定其光合指标。结果表明，随着干旱胁迫的增强，2个大豆品种单株叶面积、叶色值、净光合速率和单株粒质量均呈下降趋势，但不同品种之间的下降趋势存在差异。2个时期耐密植品种‘垦丰16’在轻度干旱和重度干旱条件下，叶面积下降与对照差异均为不显著和显著，而常规品种‘绥农14’叶面积下降为显著和极显著水平；耐密植品种‘垦丰16’在受到干旱胁迫后叶色值变化不明显，常规品种‘绥农14’在受到干旱胁迫下，叶色值与对照差异达显著或极显著水平；在重度干旱胁迫条件下，2个品种的净光合速率均极显著下降，在轻度干旱条件下，耐密植品种‘垦丰16’和常规品种‘绥农14’与对照差异分别达显著和极显著水平；R2期轻度和重度干旱条件下，耐密植品种‘垦丰16’单株粒质量下降与对照差异不显著和显著，而常规品种‘绥农14’则下降与对照差异显著和极显著，R6期‘垦丰16’单株粒质量下降与对照差异为显著和极显著，而常规品种‘绥农14’则均与对照差异达极显著水平。因此，从单株叶面积、叶色值、净光合速率和单株粒质量变化趋势可以看出，耐密植品种‘垦丰16’的抗旱能力强于常规品种‘绥农14’。
In order to confirm the influence of drought stress on photosynthetic characteristics of different soybeans. We took the density-tolerant soybean variety ‘Kenfeng 16’ and conventional cultivars ‘Suinong 14’ as materials, and analyzed their photosynthetic indexes under mild drought, severe drought and conventional water management (control) in the period of flowering period (R2) and filling period (R6).The results showed that the leaf area per plant, leaf color value, net photosynthetic rate and grain mass per plant of two different soybean varieties presented a decline trend under drought stresses, and differences were detected between varieties. Compared the effects of mild drought and severe drought in two period, the decline trend of the leaf area per plant of ‘Kenfeng 16’ reached no significant and significant level, and the ‘Suinong 14’ reached significant or extremely significant level. The leaf color of the ‘Kenfeng 16’ had no obvious changes and the ‘Suinong 14’ reached significant or extremely significant level with the control. The net photosynthetic of the two varieties reached extremely significant decline level under the severe drought and the changes of the ‘Kenfeng 16’ and ‘Suinong 14’ compare with the control reached significant or extremely significant level. The grain mass per plant of ‘Kenfeng 16’ decline reached no significant and significant level and the ‘Suinong 14’ reached significant and extremely significant level under the mild drought and severe drought in R2. The grain mass per plant of ‘Kenfeng 16’ decline reached significant and extremely significant level and the ‘Suinong 14’ reached extremely significant level under the mild drought and severe drought in R6. From the changes trend of the leaf area per plant, leaf color value, net photosynthetic rate and grain mass per plant we can conclusion that the drought resistance ability of dense planting soybean varieties ‘Kenfeng 16’ is stronger than conventional cultivars ‘Suinong 14’.