不同收获期玉米杂交种种子活力研究

Vigor Traits of Maize Seed Harvested in Different Filling Periods

选择硬粒型先玉335、马齿型郑单958和吉祥1号3个杂交种,研究河西制种基地玉米杂交种种子成熟度与种子活力的关系。研究结果表明,不同玉米杂交种授粉后不同采收期对种子活力影响影响很大,灌浆前期种子成熟度低,具有一定的发芽率,但种子抗逆能力差,低温冷害后的冷浸发芽率大幅度降低,田间出苗率更低;随着灌浆时期的延后,种子成熟度提高,抗逆能力逐渐增强,授粉后52 d采收3个品种冷浸发芽率达到标准发芽率的96.1%-97.6%,田间出苗率达到标准发芽率的80.4%-82.6%。授粉后57 d采收3个品种冷浸发芽率超过86%,达到标准发芽率的91%;田间出苗率达到最高（91%）,是标准发芽率的95%。甘肃武威制种基地先玉335授粉后52 d以后（9月15日）收获,郑单958和吉祥1号授粉后57 d以后收获种子活力达到最高,比目前生产上收获期提前10-15 d,可有效避免早霜对玉米种子冻害的影响。

Three genotypes（hybrid XY335 and ZD958 and JX1） were used to study the relationslalp between harvesting time and vigor of the maize seeds. The results of the experiment showed that, seed maturity and vigor at different days after pollination had a great difference. In the early filling stage, there was a certain germination rate, and seed maturity was low, but the ability to withstand adversity of the seed was poor. After chilling damage, cold soak germination rate was significantly reduced, and the rate of field emergence was lower. With grain filling moving forwards, seed vigor, maturity and resistance increased. At 52 d after pollination, germination value at cold test was 96.1%-97.6% of GS and field emergency value was 80.4%-82.6% of GS for the three genotypes. At 57 d after polli- nation, germination value at cold test was above 86% and up to 91% of GS, and field emergency value was up to 95% of GS. Suitable harvesting started from 52 DAP onwards for XY335, and 57 DAP for ZD958 and JX1, 10 to 15 days before usually harvesting, to prevent frost damage on seed quality in Wuwei Gansu.