光照和温度对小叶章种子萌发及其幼苗生长的影响

Effects of light and temperature on seed germination and seedling growth of Deyeuxia angustifolia

采用2种光照和8种温度处理研究了光照和温度对小叶章种子萌发及其幼苗生长的影响.结果表明,除30℃外,其他温度处理光照和黑暗处理的种子萌芽率差异不显著,种子萌发表现为非光敏性.在10～35℃,小叶章种子都能萌发,但萌发适宜温度为20～30℃,最适温度为30℃,最大萌芽率为54%.高温度处理的种子一般比低温度处理的种子萌发早,如30℃处理的在第2天就开始萌发,而10℃处理的在第4天才开始萌发.在适宜的温度时光照能促进小叶章幼苗的生长,在25℃和30℃,光照处理的幼苗在第10天的生长高度和最大根长都大于黑暗处理.幼苗在不同温度下生长差异较大,其中20～30℃的最大根长无显著差异,但比其他处理的大,为小叶章幼苗生长的适宜温度.

Using two light and eight temperature treatments, the effects of light and temperature on seed germinauon and seedling growth of Deyeuxia angustifolia were investigated. The results showed that at the same temperature, the germination ratios between light and dark treatments had insignificant difference except at 30 ℃, indicating that the plant is light-insensitive. Deyeuxia angustifolia can germinate in a wide range of temperature, from 10 ℃ to 35 ℃, and the suitable temperature was 20 - 30 ℃. Germination ratios at 30 ℃ was 54%. The time for starting germination was earlier at high temperature treatment than at low temperature treatment. For example, germination was started on the second day at 30 ℃, but on the fourth day at 10 ℃. At 25 ℃ and 30 ℃, seedlings under light condition were highest with longest root in comparison with dark treatments. It was clear that light can promote seedling growth of Deyeuxia angustifolia at the suitable temperature. Seedling growth was also different with temperature. The suitable temperature for seedling growth was 20 - 30 ℃, under which roots were longest in comparison with other temperature treatments.