Freitas Daiane M, Reis Ademir, Bortoluzzi Roseli L da Costa, Santos Marisa
Rev Biol Trop. 2014 Dec;62(4):1597-608. doi: 10.15517/rbt.v62i4.13012.
The genus Desmodium is represented in Santa Catarina State, Brazil, by 13 species, all with lomen- taceous fruits. Shape, size and isthmus margin of loments vary, while the surface is glabrous, or covered by trichomes of different types. Morphological diversity of trichomes becomes particularly relevant to taxonomic description. The trichome types present on the surface of Desmodium fruits provide data for the identification and classification of species in the State. To assess this, three fruits of each species were collected and deposited at two herbaria, HBR and FLOR, in Santa Catarina, Brazil. Some rehydrated samples were examined using light microscopy (LM); and some sections were exposed to the following histochemical reagents: Sudan III for oils and Thionine for mucilage. The structural aspects of trichomes can be classified into uni- or multicellular and may still be simple, i.e., nonglandular or glandular. Using scanning electron microscopy (SEM), five types of trichomes were identified and analyzed among the Desmodium species studied: uncinate, uniseriate, globose multicellular, globose unicellular and subulate. Characteristics, such as loment margin and article form, glabrescent or pillous indument, trichome type, with or without papillous epidermal cells and epicuticular striations, showed relevant diagnostic value. An identification key was developed for Desmodium species from Santa Catarina State, Brazil, based on macro and micromorphological characters of the fruit.
在巴西圣卡塔琳娜州，山蚂蝗属有13个物种，其果实均为节荚果。节荚果的形状、大小和节间边缘各不相同，表面无毛，或覆盖着不同类型的毛状体。毛状体的形态多样性对于分类描述尤为重要。山蚂蝗属果实表面的毛状体类型为该州物种的鉴定和分类提供了数据。为评估这一点，采集了每个物种的三个果实，并保存在巴西圣卡塔琳娜州的两个植物标本馆，即HBR和FLOR。一些复水后的样本用光学显微镜（LM）进行了检查；一些切片用以下组织化学试剂处理：用于检测油脂的苏丹III和用于检测黏液的硫堇。毛状体的结构特征可分为单细胞或多细胞，也可能是简单的，即非腺毛或腺毛。利用扫描电子显微镜（SEM），在研究的山蚂蝗属物种中鉴定并分析了五种毛状体类型：钩状、单列、球形多细胞、球形单细胞和钻形。节荚边缘和节荚形态、近无毛或具柔毛的被毛、毛状体类型、有无乳头状表皮细胞和表皮条纹等特征具有重要的诊断价值。基于果实的宏观和微观形态特征，为巴西圣卡塔琳娜州的山蚂蝗属物种编制了一份鉴定检索表。
