硼对油菜花器官发育和结实性的影响

EFFECT OF BORON ON FLORAL ORGANSDEVELOPMENT AND SEED-SETTINGOF RAPESEED (Brassica napus L.)

在缺硼和正常供硼条件下，油菜花器官的含硼量明显高于叶片，尤其是雌蕊和雄蕊中的含量可达同期叶片的两倍左右；硼过量时则以叶片含硼量最高。缺硼导致雄蕊长度、干重下降，花药绒毡层异常，花粉囊分化受阻。缺硼和硼过量均使油菜单株有效角果数，每角果籽粒数及结角率、结籽率、油菜籽产量下降。硼对角果的胚珠数没有影响。与宁油７号相比，宁油８号油菜品种更易受缺硼和过量硼的影响。

ot experiments were conducted to study the effects of boron on floral organsdevelopment and seed-setting of rapeseed (Brassica napus L.).The results are asfollows:In boron-free(B_0)and boron-normal (B_1) plants, boron concentrations offloral organs were greater than those of leaves, especially with boron in pistil andstamen twice as high as that in leaves. But leaves had the greatest boron concentra-tion when boron was excess (B_2). Boron deficiency led in reduction of the lengthand weight of stamen and in abnorniality of anther tapetum development.Diffe-rentiation of pollen sac was inhibited. It was found that both boron deficiencyand excess reduced the numbers of effective siliques per plant and seeds per silique,rate of siliques,rate of seed-setting, and rape seed yield. The effect of boron onthe number of ovules per silique was not significant. Compared with Ningyou No.7 (a high erucic acid type),Ningyou No. 8 (a low erucic acid type) was moresensitive to boron-deficiency and boron-excess.