5种北美栎树秋冬季叶色变化机理分析

Leaf Color Transformation of 5 America Introduced Quercus spp. in Autumn and Winter

  • 摘要: 以栽植于苗圃的4年生水栎、纳塔栎、舒玛栎、沼生栎、柳叶栎为研究对象,在秋冬转色期对其叶片的叶绿素、类胡萝卜素和花青素3种色素及可溶性糖含量进行定期测定,同时记录转色期气温变化,研究转色期叶片色素含量变化与环境影响因子的关系。结果表明:随着气温的下降,5种栎树叶片叶绿素a和叶绿素b均呈先快后慢的下降趋势,而花青素含量呈波动上升趋势。其中叶绿素a含量从大到小依次为沼生栎>水栎>舒玛栎>纳塔栎>柳叶栎;10月12日至11月5日,纳塔栎、舒玛栎和柳叶栎中的叶绿素b降幅最大。类胡萝卜素含量变化呈波动状态,除柳叶栎在试验后期有较为明显的上升趋势外,其他4种栎树在整个试验期变化不大。5个树种花青素含量与日平均温度呈极显著负相关(P<0.01),水栎和柳叶栎叶中的花青素与可溶性糖含量呈显著正相关。由此得出,秋冬季日平均气温的下降促进了5种栎树叶片花青素的积累,直接影响了叶色的变化。

     

    Abstract: Five introduced species of 4-year oak seedlings including Quercus nigra, Q. nuttallii, Q. shumardii, Q. uercus palustris, Q. phellos were used to measure the contents of chlorophyll, carotenoids, anthocyanin and soluble sugar in leaves. The air temperature and humidity changes during the experiment were recorded synchronously. The relationship between the change of pigment content in leaves and environmental factors was studied. The results showed that with the decreasing of air temperature, contents of chlorophyll a and b in leaves of 5 oak species decreased significantly first and then slowly, and the content of anthocyanin presented a trend of fluctuant rise. The chlorophyll a content in descending order was as follows: Q. palustris > Q. nigra > Q. shumardii > Q. nuttallii > Q. phellos. During the test period from October 12 to November 5, the chlorophyll b of Q. nuttallii, Q. shumardii and Q. phellos decreased the most. Variations of carotenoid contents exhibited significant increase in Q. phellos, while fluctuated in the other 4 species. The average temperature had a significantly negative correlation with anthocyanin in 5 oak species(P<0.01), and there was a significant positive correlation between anthocyanin and soluble sugar content in Q. nigra and Q. phellos. This concluded that lower temperature accelerated the accumulation of anthocyanin in leaves of 5 oak species in autumn and winter and directly affected the change of leaf color.

     

/

返回文章
返回