Anatomia foliar e trocas gasosas de Trembleya parviflora(D. Don) Cogn. (Melastomataceae) em ambientes de cerrado e campo rupestre no Parque Ecológico Quedas do Rio Bonito

Abstract

The objective of this work was to analyze and describe the anatomical and foliar gas exchange characteristics of Trembleya parviflora in Cerrado and rupestrian environments in the Eucalyptus Park of Rio Bonito in Lavras -MG. The samples were collected in September 2017. The infrared gas analyzer (IRGA) was used for the gas exchange characteristics. In order to analyze the leaf anatomy, leaves were collected and sections for dermal and transverse were performed, using usual microtechnical procedures. The plants of the cerrado environment differed in relation to the plants in the field environment because they had a higher transpiratory rate (E), as well as the internal carbon concentration (Ci), and a higher internal carbon concentration was also observed in relation to the external one ( Ci / Ca). The leaf anatomy of Trembleya parviflora was different among the environments, where the thickness of the paliçadic and spongy parenchyma, adaxial and abaxial epidermis, and the area of the intercellular spaces are larger in the field environment. The species presented xeromorphic characteristics in the two environments, such as: isobilateral mesophyll, thick cuticle, support tissues (sclerenchyma), high density of trichomes and idioblasts with solid inclusions (drusen)