《植物生理学报》 2012, 48(10): 986-992

我国两种特有苏铁的生态环境及叶片结构

韦丽君^1,2, 陈金湘¹, 黄玉源^3,4,*, 黄良美⁵

1湖南农业大学农学院, 长沙410128; 2广西壮族自治区亚热带作物研究所, 南宁530001; 3仲恺农业工程学院生命科学学院,广州510225; 4广西大学农学院, 南宁530005; 5广西壮族自治区环境监测中心站, 南宁530028

通信作者：黄玉源；E-mail: lqxhyy@yahoo.com.cn；Tel: 13322817462

摘　要：

考查广西百色西林县叉孢苏铁和广西百色田东县锈毛苏铁的生态环境, 结合观测其叶片的内部结构来探讨其与生境 的适应性。结果表明叉孢苏铁群落乔木和灌木均9种, 藤本8种, 草本18种, 蕨类2种, 空间格局明显; 锈毛苏铁群落乔木和灌 木均5种, 草本6种, 蕨类4种, 空间格局不明显。两种苏铁的羽片均由表皮、栅栏组织、海绵组织和副转输组织构成; 叶轴 均由表皮、厚壁组织、薄壁组织和维管组织构成。不同之处在于, 锈毛苏铁的羽片、角质层、栅栏组织和叶轴的厚壁组 织均较叉孢苏铁的厚, 分别是叉孢苏铁的1.82倍、2.32倍、1.79倍和2.45倍左右; 锈毛苏铁叶片的表皮之下有下皮层、各组 织中有丰富的异细胞, 而叉孢苏铁的无或较少; 锈毛苏铁的羽片中有黏液道, 而叉孢苏铁的无。叉孢苏铁的叶片表现为弱 旱生异面叶, 锈毛苏铁的则表现为强旱生异面叶。

关键词：叉孢苏铁; 锈毛苏铁; 生境; 叶片结构; 适应性; 养护管理

收稿：2012-08-10   修定：2012-09-19

资助：国家自然科学基金(30260007)。

Ecological Environment and Leaf Structure of Two Species of Cycas Only in China

WEI Li-Jun^{1, 2}, CHEN Jin-Xiang¹, HUANG Yu-Yuan^{3, 4, *}, HUANG Liang-Mei⁵

¹College of Agriculture, Hunan Agricultural University, Changsha 410128, China; ²Guangxi Zhuang Autonomous Region Institute of Subtropical Crop, Nanning 530001, China; ³College of Life Sciences, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; ⁴Agricultural College, Guangxi University, Nanning 530005, China; ⁵Guangxi Zhuang Autonomous Region Environmental Monitoring Center, Nanning 530028, China

Corresponding author: SHAO Ling; E-mail: lqxhyy@yahoo.com.cn; Tel: 13322817462

Abstract:

The present study investigated ecological environment and leaf structure of Cycas segmentifida in Xilin county of Guangxi and Cycas ferruginea in Tiandong county of Guangxi, their adaptability was also discussed. The main results showed that C. segmentifida community included 9 arbors, 9 shrubs, 8 vines and 18 herbs and 2 ferns, and spatial structure was obvious. C. ferruginea community included 5 arbors, 5 shrubs, 6 herbs and 4 ferns, while spatial structure was not obvious. The leaf of two Cycas composed of epidermis, palisade tissue, sponge tissue and accessory transfusion tissue. The rachi composed of epidermis, sclerenchyma, parenchym tissue and vascular tissue. The differences was that the pinna, cuticle, palisade tissues, and the sclerenchyma in rachi of C. ferruginea was very thicker than that of C. segmentifida and the thickness in C. ferruginea was about 1.82-, 2.32-, 1.79-, and 2.45-time thicher than in C. segmentifida, respectively. There was hypodermis under the epidermis and abundant idioblasts in every tissue of C. ferrugine, but few or a few in C. segmentifida. Three mucilage canals distributed in the pinna of C. ferrugine, but no mucilage canal distributed in pinna of C. segmentifida. The leaf of C. segmentifida appeared weakly xeriophytic bifacial leaf, but the leaf of C. ferruginea appeared bifacial leaf with strong drought tolerance.

Key words: Cycas segmentifida; Cycas ferruginea; habitat; leaf structure; adaptability; conservation management