Appezzato-da-Glória Beatriz, Cury Graziela
Departamento de Ciências Biológicas, Escola Superior de Agricultura 'Luiz de Queiroz', Universidade de São Paulo, Piracicaba, SP, Brasil.
An Acad Bras Cienc. 2011 Sep;83(3):981-92. doi: 10.1590/s0001-37652011005000018. Epub 2011 Jul 15.
In the Brazilian Cerrado (neotropical savanna), the development of bud-bearing underground systems as adaptive structures to fire and dry periods can comprise an important source of buds for this ecosystem, as already demonstrated in the Brazilian Campos grasslands and North American prairies. Asteraceae species from both woody and herbaceous strata have subterranean organs that accumulate carbohydrates, reinforcing the adaptive strategy of these plants to different environmental conditions. This study aims to analyse the morpho-anatomy of underground systems of six species of Asteraceae (Mikania cordifolia L.f. Willd., Mikania sessilifolia DC, Trixis nobilis (Vell.) Katinas, Pterocaulon alopecuroides (Lam.) DC., Vernonia elegans Gardner and Vernonia megapotamica Spreng.), to describe these structures and to verify the occurrence and origin of shoot buds, and to analyse the presence of reserve substances. Individuals sampled in Cerrado areas in São Paulo State showed thick underground bud-bearing organs, with adventitious or lateral roots and presence of fructans. Xylopodium was found in all studied species, except for Trixis nobilis, which had stem tuber. The presence of fructans as reserve, and the capacity of structures in the formation of buds indicate the potential of herbaceous species of Asteraceae in forming a viable bud bank for vegetation regeneration in the Brazilian Cerrado.
在巴西塞拉多（新热带稀树草原），作为适应火灾和干旱期的结构，带芽地下系统的发育可能是该生态系统芽的一个重要来源，巴西坎普斯草原和北美草原已有相关证明。来自木本和草本层的菊科物种都有积累碳水化合物的地下器官，强化了这些植物对不同环境条件的适应策略。本研究旨在分析六种菊科植物（心叶乳菀Mikania cordifolia L.f. Willd.、无柄乳菀Mikania sessilifolia DC、高贵三肋果Trixis nobilis (Vell.) Katinas、看麦娘翼茎草Pterocaulon alopecuroides (Lam.) DC.、雅致斑鸠菊Vernonia elegans Gardner和大果斑鸠菊Vernonia megapotamica Spreng.）地下系统的形态解剖结构，描述这些结构并验证茎芽的出现和起源，分析储备物质的存在情况。在圣保罗州塞拉多地区采集的个体显示出厚实的带芽地下器官，有不定根或侧根以及果聚糖的存在。除高贵三肋果外，所有研究物种中均发现了木质根状茎，高贵三肋果有茎块茎。果聚糖作为储备物质的存在以及结构形成芽的能力表明，菊科草本物种在为巴西塞拉多植被再生形成可行的芽库方面具有潜力。
