春小麦结实特性对穗粒数的影响

试验以19个春麦品种为材料,试图探讨影响春麦穗粒数的生育阶段。结果表明,小花数多是穗粒数多的必要不充分条件;受精前的退化小花数相对来说要少于受精败育数和成胚后籽粒的退化数,也即受精前的退化小花数并不是限制穗粒数的主要因子;增加小花数同时减少小花的退化、减少受精败育数和成胚退化数是现阶段提高春麦穗粒数的关键。对于穗粒数多于40粒的品种减少小花数的退化提高可育小花数是增加穗粒数的关键;对于穗粒数在30￣40粒之间的品种减少成胚后籽粒的退化是提高穗粒数的关键;对于穗粒数低于30粒的品种,要增加受精前的小花数,同时要针对不同的品种,采取措施减少受精败育数或成胚后籽粒的退化数才能有效地提高穗粒数。

Influence of bearing characteristics on grains of a spike in spring wheat

The growing stages determining grains of an ear in spring wheat were studied in 19 spring wheat cuhivars. The results showed that more florets were only necessary factor for more grains in a spike, but not sufficient. The aborted florets before fertilization were generally fewer than that after fertilization and the aborted seeds after embryo formation, or the aborted florets before fertilization were not the main factor restricting the seeds in a spike of wheat. The key approach for more grains of a spike in wheat was to increase florets and to reduce degenerated florets and aborted seeds in fertilization as well as in embryo formation. The main step of increasing grains of a spike should be to reduce aborted florets for the cuhivars with over 40 grains and to reduce degenerated seed after embryo for those with 30-40 grains and to increase florets before fertilization for ones with below 30 grains. Meanwhile, the methods for lower aborting seeds both in fertilization and in embryo formation stages should be accepted to increase seeds of a spike efficiently.