不同密度网罩对甘蓝型油菜隔离制种效果比较

旨在考察网罩密度对油菜制种的影响。以甘蓝型油菜Polima和萝卜2种胞质雄性不育系为试验材料,研究网罩对光照、温度、湿度、菌核病发病率以及制种产量的影响。结果表明：（1）网罩内光照强度随密度增加而显著下降。（2）罩内温度普遍上升,但是差异并不都显著。（3）网罩内湿度总体上是随网罩密度增加而升高。但是,也存在例外。（4）随着密度的增加,网罩内菌核病发病率升高。（5）试验中即使最大密度的网罩（160目）,也不能完全阻隔外来花粉。（6）对于Polima和萝卜胞质雄性不育系,相同密度的网罩造成杂交制种产量的下降幅度相近。因此,网罩对Polima和萝卜胞质雄性不育系存在相似影响,现在常用的网罩密度不能达到完全阻隔外来花粉的目的。

Hybrid Seed Production of Brassica napus L.: Isolation Effect Comparisons of Different-density Nets

The objective of this study is to investigate the effect of nylon net density on seed production of Brassica napus L. Polima cytoplasmic male sterile (Polima CMS) line and a radish cytoplasmic male sterile (Ogu CMS) line of Brassica napus L. were used as materials. The effects of nets on the light, temperature, humidity, the incidence of Scleritinia sclerotiorum and seed-production yield were investigated. The results were as following. (1) Light intensities in the nets decreased significantly along with the increase of net densities. (2) The temperature in all nets raised, but some of the temperature increase did not reach a significant level. (3) Humidity in most nets increased with the increase of net density, but there were some exceptions. (4) The incidence of Scleritinia sclerotiorum increased with the increase of net density. (5) Even the densest net (160 net mesh number per square inch (NMNPSI)) could not prevent outside pollens entering into the nets. (6) Of the same density nets, the decrease rate of hybrid yield of Polima CMS lines was similar to that of Ogu CMS lines. Consequently, the effects of net density on both Polima CMS and Ogu CMS are similar, the present popular densities of nets are not enough to prevent outside pollens entering into nets.