川西高原12种风毛菊属植物瘦果形态和发芽特征  

Morphology and Germination Features of Achenes of 12 Species of the Genus Saussurea (Asteraceae) in Western Sichuan Plateau

作　　者：张大才[1] 李双智[1] 候雄辉[1] 张明启[1] 

机构地区：[1]西南林业大学林学院,云南昆明650224

出　　处：《植物分类与资源学报》2013年第3期273-279,共7页Plant Diversity

基　　金：科技部科技基础性工作专项重点项目(2007FY110100);国家自然科学基金(31160044)

摘　　要：分析了12种风毛菊属植物瘦果形态、果皮微形态和发芽特征,并探讨了瘦果形态和发芽特征与植物地理分布范围之间的关系。瘦果形状包括倒披针形、圆柱形和圆柱状倒三角形3种类型。瘦果长度、宽度和厚度变幅较大,平均变幅达10%。瘦果果皮微形态可区分为条纹型、网纹型和孔纹型,以条纹型最为普遍。种内瘦果微形态特征十分稳定,是很好的分类学依据。种子(瘦果)发芽率差异较大,最高达98%,而最低仅为40%。风毛菊属植物地理分布范围与瘦果冠毛长度和百粒瘦果重量显著相关,与瘦果饱满率、冠毛比重、发芽率之间均为正相关,但相关性不显著。本文涉及的风毛菊属植物瘦果冠毛比重较高,有利于远距离传播,且高发芽率和百粒瘦果重量为幼苗的成功定居提供了保障,在青藏高原有更广的潜在分布区。This paper analyzed the shapes of achenes of 12 species in the genus Saussurea DC., and their mieromor- phological features and germination, and discussed the relationship between achene shapes and germination character- istics with geographical distribution. The mainly achene shapes included three types, namely oblanceolate, cylindrical and eylindrical-obtriangular. The amplitude of achene length, width and thickness was large, and the mean value was over 10%. The surface of achenes can be divided into 3 types based on micromorphological characters, namely striate ornamentation, reticulate ornamentation and pitted ornamentation, and the stripe type was the most common. The mi- cromorphological features of aehenes are stable, and it was an ideal taxonomic character. The percentage of germina- tion differed greatly among species, and the highest was 98%, but the lowest was just 40%. The geographical distri- bution of species of Saussurea was significantly correlated with their length of achene pappus and 100-grain weight. It also positively correlated with achene plumpness, and the proportion of pappus weight to achene, but the correlation was insignificant. These species of Saussurea in this paper had a high proportion of pappus weight to achene, which was good for long-distance dispersal, and their high germination rate and lO0-grain weight provided security for the growth of seedling, therefore, these species potentially had a wide distribution in the Qinghai-Tibet Plateau.

关 键 词：微形态 地理分布 冠毛 风毛菊属 瘦果 

分 类 号：Q944[生物学—植物学]