光对烟草叶片不定芽发生和生长的影响

EFFECTS OF DIFFERENT LIGHT INTENSITY AND SPECTRAL QUALITY ON BUD FORMATION AND GROWTH IN TOBACCO LEAF CULTURES

测定了不同强度(0～4.2 mW/cm^2)的红光、蓝光和白光对烟草叶片不定芽发生及生长的影响。结果发现,蓝光在低强度(0.4 mW/cm^2左右)时,对芽发生的诱导作用最强,随着光强的增加或减弱,芽的发生率均有所下降。红光在辐照度为0～4.2 mW/cm^2的范围内,随着强度的增加,对芽的诱导作用也增大。白光的影响类似红光。就芽的生长来说,随着光强的增加抑制作用也增大。在光照条件下的芽发生和生长情况都较无光照的好。

Isolated leaves of Nicotiana tabacum were cultured in lights with varying wave-length and intensity and the dark, with 0.5 mg/L BA and 0.05 mg/L NAA inthe MS medium. Adventitious buds were initiated. Blue light with low intensity(about 0.4 mW/cm^2) could increase the bud formation, but the formation of budswas reduced when either higher or lower intensity was used. Red and white light(up to 4.2 mW/cm^2) apparently increased the bud formation with increasing in-tensity. With the growth of explant, high intensity of light was unfavourable.Both bud formation and growth were inhibited in the dark. The results suggestthat light plays different roles In differentiation and growth of plants, and itseffects may be exerted through phytochrome and other photoreceptor.