Carneiro Renê G S, Isaias Rosy M S, Moreira Ana S F P, Oliveira Denis C
Laboratório de Anatomia Vegetal, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil.
Laboratório de Anatomia Vegetal, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
Front Plant Sci. 2017 Sep 27;8:1622. doi: 10.3389/fpls.2017.01622. eCollection 2017.
The development of gall shapes has been attributed to the feeding behavior of the galling insects and how the host tissues react to galling stimuli, which ultimately culminate in a variable set of structural responses. A superhost of galling herbivores, , hosts a bizarre "horn-shaped" leaflet gall morphotype induced by an unidentified species of Diptera: Cecidomyiidae. By studying the development of this gall morphotype under the anatomical and physiological perspectives, we demonstrate the symptoms of the Cecidomyiidae manipulation over plant tissues, toward the cell redifferentiation and tissue neoformation. The most prominent feature of this gall is the shifting in shape from growth and development phase toward maturation, which imply in metabolites accumulation detected by histochemical tests in meristem-like group of cells within gall structure. We hypothesize that the development of complex galls, such as the horn-shaped demands the reacquisition of cell meristematic competence. Also, as mature galls are green, their photosynthetic activity should be sufficient for their oxygenation, thus compensating the low gas diffusion through the compacted gall parenchyma. We currently conclude that the galling Cecidomyiidae triggers the establishment of new sites of meristematic tissues, which are ultimately responsible for shifting from the young conical to the mature horn-shaped gall morphotype. Accordingly, the conservative photosynthesis activity in gall site maintains tissue homeostasis by avoiding hypoxia and hipercarbia in the highly compacted gall tissues.
瘿形状的形成归因于造瘿昆虫的取食行为以及宿主组织对造瘿刺激的反应，最终导致一系列可变的结构反应。作为造瘿食草动物的超级宿主，[具体植物名称未给出]宿主一种由未鉴定的双翅目物种：瘿蚊科诱导形成的奇异“角状”小叶瘿形态型。通过从解剖学和生理学角度研究这种瘿形态型的发育，我们展示了瘿蚊科对植物组织的操控症状，即朝着细胞再分化和组织新形成的方向。这种瘿最显著的特征是从生长发育阶段到成熟阶段形状的变化，这意味着在瘿结构内类似分生组织的细胞群中通过组织化学测试检测到代谢物的积累。我们假设复杂瘿的发育，如角状瘿，需要重新获得细胞分生能力。此外，由于成熟的瘿是绿色的，它们的光合作用活性应该足以满足其氧化需求，从而补偿通过紧密的瘿薄壁组织的低气体扩散。我们目前得出结论，造瘿瘿蚊科触发了分生组织新位点的建立，这些位点最终负责从年轻的圆锥形瘿形态型转变为成熟的角状瘿形态型。因此，瘿部位保守的光合作用活性通过避免高度紧密的瘿组织中的缺氧和高碳酸血症来维持组织稳态。
