摘要
构树Broussonetia papyrifera具有良好的抗逆性,在受到逆境时自身形态建成发生改变来应对环境。研究通过对一年生构树幼苗进行干旱胁迫和盐胁迫,测定叶型、光合气体参数、黄酮含量并采用计盒法分析构树叶片分形维数,结果表明干旱胁迫和盐胁迫都能显著减弱构树光合作用,相较于对照组,干旱胁迫与盐胁迫的构树叶片胞间CO_(2)浓度、气孔导度和净光合速率分别显著下降了23.41%与41.16%、62.50%与69.72%、16.43%与17.60%。盐胁迫导致构树深裂叶占比显著增大,较对照组增加了58.96%。两种胁迫都能增加构树正视图和俯视图的叶片分形维数,尤其是两种胁迫分别使正视图的分形维数显著提高了7.90%、11.58%。同时,盐胁迫使黄酮在老叶中显著降低了17.85%。因此,面临渗透胁迫时,构树通过改变叶片形状、增加叶片占据空间的有效性和减少黄酮在老叶中的积累来应对。
Broussonetia papyrifera has good resistance to adverse stresses and can adapt to the adverse stress by changing its morphogenesis. In this study, the one-year-old B. papyrifera seedlings were subjected to drought and salt stress, and then leaf shape, photosynthetic gas parameters, and flavonoid content were measured,and leaf distribution fractal dimension was analyzed using the box-counting method. The results showed that both drought and salt stress inhibited the photosynthesis of B. papyrifera significantly. Compared with the control group, intercellular CO_(2) concentration, stomatal conductance and photosynthetic rate of B. papyrifera leave under drought stress and salt stress decreased by 23.41% and 41.16%, 62.50% and 69.72 %, 16.43% and 17.60%, respectively. Salt stress led to a significant increase in the proportion of deeply lobed leaves, which was 58.96 % higher than that of the control group. Both drought stress and salt stress increased the leaf distribution fractal dimension of B. papyrifera at the front view and vertical view, and the two stresses increased the leaf distribution fractal dimension at the front view by 7.90% and 11.58% significantly and respectively. Meanwhile,salt stress reduced the accumulation of flavonoids in old leaves by 17.85% significantly. Therefore, our results suggest that B. papyrifera changed the leaf shape, increased the effectiveness of leaf space occupation and reduced the accumulation of total flavonoids in old leaves to cope with osmotic stress. Our results will contribute to the exploration of the response mechanism in B. papyrifera leaves under osmotic stress.
作者
龙硕
张欢欣
钱志良
姚靖泓
王洋文
刘禹含
孟森
胡文涛
LONG Shuo;ZHANG Huanxin;QIAN Zhiliang;YAO Jinghong;WANG Yangwen;LIU Yuhan;MENG Sen;HU Wentao(College of Forestry and Landscape Architecture,South China Agricultural University/Guangdong Provincial Key Laboratory of Forest Plant Germplasm Innovation and Utilization,Guangzhou,Guangdong510642,China;Key laboratory and Grassland Administration on Tropical Forestry,Chinese Academy of Forestry,Guangzhou,Guangdong510520,China)
出处
《林业与环境科学》
2022年第6期109-115,共7页
Forestry and Environmental Science
基金
国家自然科学基金青年科学基金项目(32001289)。
关键词
干旱胁迫
盐胁迫
叶型
分形维数
构树
water stress
salt stress
leaf type
fractal dimension
Broussonetia papyrifera
