玉米花粒期群体光合性能与高产潜力研究

Study of Canopy Photosynthesis Property and High Yield Potential after Anthesis in Maize

对两个高产潜力不同的玉米品种,在两种肥力条件下的研究表明:高产潜力大的玉米品种和高肥处理的植株,花粒期(开花—成熟)群体光合速率下降慢,高值持续期长。高产品种群体呼吸速率亦高,但群体呼吸占群体光合的百分数低,群体干物质净积累率高。花粒期冠层气孔导度和蒸腾速率以及根伤流量、叶绿素含量等主要生理指标,高产品种和高肥处理显著优于低产品种和低肥处理。高产潜力大的品种开花30天后,籽粒生长率高,有效灌浆期长。延长灌浆期的群体光合速率高值持续期和籽粒有效灌浆期是玉米高产的潜力所在。

Two maize varieties with different yield potentials were studied under conditions with two different levels of soil fertility. The results indicated that, during the period between anthesis, the CAP of variety with higher yield potential and under higher soil fertility decreased slower than that of variety with lower yield potential, the higher value remained longer. The respiration rate of the higher-yielding variety was also higher, but the CP/CAP was lower, the accumulation of dry matter was also higher with physiological characters such as canopy stomatal conductance, transpiration rate, quantity of root flowing and chlorophyll content, the higher-yielding variety performed obviorisly better than the lower yield one so did the higher soil fertility treatment hut the 30th day after anthesis, the growth rate of seed development of the variety with higher yield potential was higher, and the effective grain-filling duration longer. It was suggested, therefore, that the prolongation of the high-value duration of the CAP and the effective grainfilling duration might be the underlying canse of higher yield potential in maize.