Taxonomic value of histochemical features of the style in early lineages of Asteraceae

In this paper we examine lipophilic substances, tannins, proteins, reducing carbohydrates, starch, and oxalate salts in early lineages of Asteraceae to test if they are a useful complement to classification studies. Styles of mature flowers of 44 species were processed according to plant histochemical techniques and observed by means of a light microscope. Lipophilic compounds were always present in the cuticle and cell walls, and in some species were located inside the cells. Proteins were located in the style cell walls and cell interior of most of the analyzed species. No tannins were found. In general, there is a correlation in the presence of reducing sugars and proteins. Starch granules and oxalate salts were found in the style parenchyma of a few species. Cytoplasmic content of lipophilic compounds, proteins, and reducing sugars predominates in Barnadesioideae and Nassauvieae (Mutisioideae), and histochemical similarities were found among members of Gochnatioideae

本研究针对菊科（Asteraceae）早期分支类群中的脂溶性物质、单宁、蛋白质、还原糖类、淀粉及草酸盐开展检测，以探究上述成分能否作为分类学研究的有效补充手段。研究选取44个物种的成熟花花柱，采用植物组织化学技术进行处理，并借助光学显微镜完成观察。结果显示，脂溶性化合物始终存在于角质层与细胞壁中，部分物种的该类化合物还可在细胞内部检出。在多数供试物种中，蛋白质可在花柱细胞壁及细胞内部被检测到。未发现单宁成分。总体而言，还原糖与蛋白质的检出情况存在相关性。少数物种的花柱薄壁组织中可检测到淀粉粒与草酸盐。巴纳德菊亚科（Barnadesioideae）与纳骚族（Nassauvieae，隶属于Mutisioideae）的胞质中，脂溶性化合物、蛋白质及还原糖的含量占据优势；而戈氏菊亚科（Gochnatioideae）的类群间则呈现出组织化学特征的相似性。