Arquitetura foliar comparativa de Miconia sellowiana (DC.) Naudin (Melastomataceae) em diferentes fitofisionomias no Estado do Paraná, Brasil

Abstract

RESUMO -(Arquitetura foliar comparativa de Miconia sellowiana (DC.) Naudin (Melastomataceae) em diferentes fitofisionomias no Estado do Paraná, Brasil). Estudos prévios sobre M. sellowiana, em quatro fitofisionomias no Estado do Paraná, Brasil, mostraram que suas folhas apresentaram uma grande plasticidade morfológica. Este trabalho objetivou dar continuidade ao estudo sobre a plasticidade da espécie, utilizando como indicadores as seguintes características foliares: área e massa, massa específica, espessura, ângulo, comprimento, diâmetro, porcentagem do tecido mecânico e volume do pecíolo, distâncias entre veias e densidade de venação. A análise dos componentes principais (ACP) mostrou que os dois primeiros componentes explicaram 78% da variância total. O componente principal 1 (CP1), representado pelos ângulo foliar, distância da veia principal até a margem, comprimento do pecíolo, densidade de venação, massa específica e massa seca foliar, explicou 56,06% da variância total, enquanto que o componente principal 2 (CP2), representado pela área foliar, explicou 12,62% da variância total. O CP1 mostrou dois agrupamentos: um entre os indivíduos da Floresta Ombrófila Mista e Floresta Ombrófila Densa Montana e outro entre os indivíduos da Estepe Gramíneo-Lenhosa e Floresta Ombrófila Alto-Montana. Para o CP2, a distribuição é mais homogênea entre as quatro fitofisionomias estudadas. A ACP sugere o mesmo gradiente mesomórfico-xeromórfico encontrado nos estudos anteriores para M. sellowiana, mostrando que os atributos morfológicos aqui estudados são também plásticos, respondendo as condições ambientais diferenciadas entreas quatro fitofisionomias. Palavras-chave: densidade de venação, formações florestais, morfologia foliar ABSTRACT -(Comparative leaf architecture of Miconia sellowiana (DC.) Naudin (Melastomataceae) from different plant physiognomies in Paraná State, Brazil). Previous studies on M. sellowiana from four different plant physiognomies in Paraná state, Brazil, have shown that the leaves of this species have great morphological plasticity. This work continues the study on the morphological plasticity of the species, using the following characteristics of leaf architecture as indicators: area, dry weight, specific dry weight, thickness, angle, length, diameter, percent mechanical tissue, and petiole volume, venation density, and distance between veins. Principal component analysis (PCA) showed that the first two components explained 78% of total variance. Principal component 1 (PC1), represented by leaf angle, petiole length, dry weight, specific dry weight, venation density, and the ratio of the distance of the midrib to the second vein/leaf area, explained 56.06%, while principal component 2 (PC2), mainly represented by leaf area, explained 12.62% of total variance. PC1 showed two distinct groups, one formed by plants from Araucaria Forest and Dense Montane Forest, and the other by plants from Dense Upper-Montane Forest and Grassland. For PC2, the distribution is more homogenous among the plants of the fou...

Leaf Morphoanatomy of Diploon Cronquist (Sapotaceae Juss.)

“…The leaf vein system may vary in response to the environmental conditions of the different biomes. (Boeger et al 2009, Sack & Scoffoni 2013. Despite this, the leaf venation pattern is an important character used for taxonomic distinction (Ellis et al 2009, Borrero et al 2016, Coutinho 2016.…”

Allometric Relations in Leaves of Erythroxylum pauferrense: Endemic Species of Alto-Montana Forest in the Northeast Region, Brazil

“…(Souza & Amaral, 2015), Psidium cattleianum and Psychotria suterella (Moraes et al, 2013); but some studies found lower coefficient of determination for the relation between leaf and L × W for the species Crotalaria juncea L. (Cardozo et al, 2014). The results show the efficiency of the model with the product of the length and width as the predictor variable for the determination of leaf area, which may be related to a higher amount of information provided through the two dimensions (Boeger et al, 2009;Monteiro et al, 2005).…”

Functional composition of subtropical highland forests in different successional stages in southern Brazil

“…According to Cornelissen et al (2003), low values of SLA indicate that plants are investing more in structural components, which increase their resistance against desiccation and herbivory and, in the case of the present study, against frosting. Boeger et al (2009), when studying leaves of Miconia sellowiana (DC.) Naudim in communities at different stages of succession in Paraná State, Brazil, verified that in the early succession stage leaves are usually thicker and with smaller specific leaf area -a pattern similar to that found in this study.…”