鲜穗烘干法下玉米杂交种桂单0810母本种子的最佳收获期

Research on Best Harvesting Time for Seeds of Gui39722,Female Parent of Maize Hybrid Gui-dan 0810 by Artificial Drying Fresh Cob Method

研究鲜穗烘干法下玉米杂交种桂单0810母本桂39722不同熟期种子的千粒重、发芽率及其种子发芽后3叶期幼苗各性状,为玉米单粒播种技术发展提供参考。结果表明:母本桂39722授粉后43 d(即第5期)种子的千粒重近于最大,发芽率最高;该期种子的幼苗的高度最高,简易活力指数最大,根干重和冠干重最大,发芽势最强;其根长、根数、根冠也较好,根冠生长协调,因此,鲜穗烘干法下桂39722的最佳收获时期为:从开始授粉日算起,有效积温达到780.7℃、穗位叶干枯时收获,可有效地保证桂单0810种子生产过程中的最佳产量及种子质量。实际生产中,6批裸种种子13次抽样发芽结果为正常苗89.00%~95.00%,平均为91.15%。

The seeds harvested at different maturity of Gui39722, the female parent of newly-developed maize hybrid Gui-dan 0810, were studied on their 1000-kernel weight, germination rate and traits expressed at 3 leaf seedling stage after germination of seeds to identify the best harvest time by the fresh cob dried method, and then to provide scientific basis for single-grain planting in maize production. The results showed that the seeds of Gui39722, the female parent of Gui-dan 0810, harvested at the time of 43 days after pollination （ fifth harvest time） performed almost heaviest 1000-kernel weight and highest germination rate, and also expressed tallest seedling, largest simple vigor index, heaviest dry weight of crown and root with strongest seed vigor at 3 leaf seedling stage after germination, while its root length, root number and crown to root ratio performed better with a more coordinated growing for root and crown part. Therefore, under the method of artificial dr- ying fresh cob, the best harvesting time of Gui39722 was when the effective accumulated temperature after pollination reached 780.7 ~C and the ear leaf beeame dry rot. Harvested at this time, high yield and best seed vigor can be effectively guaranteed for the seed production of Gui-dan 0810. In actual production, the normal seedling rate was tested for 13 times sampling from the 6 lots of naked bulk seeds produced by farmers. The normal seedling rate ranged from 89.00 % to 95.00 % , with an average of 91.15 % , which showed a very satisfactory re- sult for the seed field production of Gui-dan 0810.