芸豆花荚期不同层次叶片对产量的贡献

Effects of Kidney Bean Leaves in Different Positions on the Yield of Plant

芸豆花荚期,中层叶片对产量贡献最大,其次是上层叶片,再其次是下层叶片。不同层次叶片对产量贡献的差异与各层叶片光合速率相关,去叶后,剩余叶片的叶绿素含量变化不大,光合作用加强,具有一定的光合补偿作用,但这种补偿作用不能完全补偿去叶引起的损失,所以去叶总是导致减产,始荚期去全叶减产82.9%。

The yield of Kidney bean （Phaseolus vulgaris L. ） was most seriously affected by the defoliation at initial-pod stage compared with the defoliation at initial-bloom stage. When the leaves of middle positions was defoliated at initial-pod stage, the percentage of reduced yield was the greatest, followed by that of defoliated leaves of upper positions. Defoliation of lower positions had lowest affected on the grain yield. The differences of contribution of Kidney bean leaves in different positions to grain yield were related to the photosynthetic rate in different leaves. After defoliation, the chlorophyll content of remained leaves were not affected, but the photosynthesis were increased. There was not full compensation for losses caused by defoliation, so grain yield was decreased by all treatments. The full defoliation decreased yield by 82.9% in intial-pod stage.