Morphology and anatomy of leaf miners in two species of Commelinaceae (Commelina diffusa Burm. f. and Floscopa glabrata (Kunth) Hassk)

Abstract

RESUMO -(Morfologia e anatomia de minas foliares em duas espécies de Commelinaceae Commelina diffusa Burm. f. e Floscopa glabrata (Kunth) Hassk)). Existem poucos relatos na literatura sobre anatomia de plantas parasitadas por agentes minadores, os quais promovem escavações ou caminhos através do consumo dos tecidos internos das plantas por larvas de diversos insetos. A proposta deste trabalho foi analisar anatomicamente a ocorrência de minas foliares em Commelina diffusa (planta cosmopolita) e Floscopa glabrata (planta anfíbia) causadas por espécies de larvas endofi tófagas de dípteros, pertencentes a duas famílias: Agromyzidae e Chironomidae. O local onde as plantas foram coletas está sujeito a inundações sazonais, e as duas espécies foram submetidas às mesmas condições climáticas. Em Commelina diffusa foram encontradas larvas da família Agromyzidae e, em Floscopa glabrata observaram-se três exuvias cefálicas de Chironomidae. Os dados anatômicos revelaram que os minadores se alimentaram apenas dos tecidos parenquimáticos do mesofi lo, formando minas lineares. Além disso, notou-se que a epiderme e as unidades vasculares de porte médio foram mantidos intactos em ambas as espécies, não apresentando alterações estruturais, como a neoformação de tecidos. Palavras-chave: anatomia vegetal, minadores, planta anfíbia, Chironomidae, Agromyzidae ABSTRACT -(Morphology and anatomy of leaf miners in two species of Commelinaceae (Commelina diffusa Burm. f. and Floscopa glabrata (Kunth) Hassk)). In specialized literature, reports on anatomy of miners in host plants are few in number. These agents trigger excavations, or paths, by consumption of plant inner tissues by larvae of several insects. The aim of this work was to investigate leaf miner occurrence in Commelina diffusa (a cosmopolitan plant) and Floscopa glabrata (an amphibious plant) using anatomical techniques. The place where the plants were collected is subjected to seasonal fl oods, consequently both the species were exposed to the same weather conditions and seasonal fl oods. This study showed that members of Agromyzidae and Chironomidae families, which are Diptera endophytophagous larvae types, were responsible for the tunnels. Moreover, in Commelina diffusa Agromyzidae larvae were found, while in Floscopa glabrata three Chironomidae cephalic exuviae were found. The miners, as can be seen from anatomical studies, used only mesophyll parenchyma tissues for feeding, causing the formation of linear mines. In addition, in both the species, the epidermis and the medium-sized vascular units were kept intact, showing no structural modifi cation, such as neoformation of tissues.

Importancia de la anatomía foliar en la caracterización de Commelinaceae medicinales en la región rioplatense (Argentina).

“…These species are mesophytic, this condition is corroborated by the stomata located at the same level of epidermal cells. It coincides with observation reported by Elb et al (2010).…”

“…The distribution of stomata on both surfaces in C. erecta var. erecta f. erecta, and only on the abaxial epidermis in T. fluminensis and both Tripogandra species are in agreement with data reported for Commelina by Elb et al (2010), and in Tradescantia by Croxdale (1998). Concerning the stomata pattern we found tetraperigenous and hexaperigenous types.…”

Oldest leaf mine trace fossil from East Asia provides insight into ancient nutritional flow in a plant–herbivore interaction

“…In the mined pinnules, boundaries between mined and unmined areas are obscure because the frass trails frequently cut across the secondary leaf veins without distorting them. This can be interpreted in two ways: the larvae might mine only epidermal cells and they did not consume mesophylls, as in the case of Phyllocnistis Zeller (Lepidoptera: Gracillariidae) 54 , 55 ; otherwise, the larvae could mine mesophyll avoiding vascular tissues (e.g., some agromyzid flies 56 ). The latter strategy is possible because the mesophyll of ferns is anatomically well-differentiated into palisade and spongy tissues 57 .…”

Anatomía foliar de hierbas terrestres medicinales que crecen en la región rioplatense (Buenos Aires, Argentina)

“…De las Commelinaceae se estudiaron dos especies, se encontraron estomas de tipo tetracíticos o tetraperígenos en Tripogandra y hexacíticos o hexaperígenos en Commelina, característicos de la familia de acuerdo con Metcalfe & Chalk (1950) y Fryns-Claessens & Van Cotthem (1973. La estructura de la lámina de Commelina, coincide con lo descripto e ilustrado por Elb et al (2010). En Euphorbia serpens (Euphorbiaceae), se hallaron estomas Fig.…”