防虫网隔离对玉米花粉扩散的影响

Effect of Fly Net Separating on Pollen Dispersal of Maize

以玉米品种K玉8号为材料,研究防虫网隔离对玉米花粉扩散的影响,以期为生产上玉米小面积制种或育种过程中防虫网孔径及高度的选择提供理论依据和技术支持。结果表明:花粉扩散观察区的异交结实率随着离花粉供体区距离的增大而逐渐减小,相同距离不同方位的玉米异交结实率差异较大,主流风下风向玉米异交结实率显著高于主流风上风向。分别采用孔径为0.106、0.058、0.042 mm的防虫网隔离明显降低了玉米花粉的扩散频率,孔径为0.058、0.042 mm的防虫网隔离效果差异较小,但均好于孔径为0.106 mm的防虫网。3.5 m和4.0 m高的防虫网隔离效果相近,但均好于3.0 m高的防虫网。因此,在生产上推荐使用3.5 m高、孔径为0.058 mm的防虫网。

The effect of fly net on the dispersal frequency of maize pollen was studied with the variety Kyu No. 8 as the subject,so as to provide theoretical basis and technical support for the choice of fitness aperture and height of the fly net during small area production of seed or breeding of maize. The results showed that the outcrossing rate of the observation area decreased steadily with the increase of distance from the pollen donor zone,there were great differences in outcrossing rate for different orientation at the same distance,and the outcrossing rate of plants downwind was significantly higher than that of those upwind. Isolation with the aperture of 0. 106 mm,0. 058 mm,0. 042 mm screens significantly reduced the pollen dispersal frequency. There was a small difference in the aperture effect between 0. 058 mm and 0. 042 mm,but all were better than the 0. 106 mm. The study also found that screens with height of 3. 5 m and 4. 0 m had better isolation effect than 3. 0 m screen. Thus,the fly net with height of 3. 5 m and aperture of 0. 058 mm was recommended for agricultural production.