Superfície da lâmina foliar de Psychotria nuda (Cham. & Schltdl.) Wawra, P. leiocarpa Cham. & Schltdl., P. stenocalyx Müll. Arg. e P. tenuinervis Müll. Arg. (Rubiaceae)

Abstract

São apresentados dados relativos à micromorfologia da superfície foliar de quatro espécies de Psychotria. O estudo foi realizado em indivíduos que ocorrem na Floresta Pluvial Tropical (Mata Atlântica). Atenção especial é dada ao tipo de cera epicuticular e da escultura da superfície dos estômatos, papilas e demais células epidérmicas.

Comparison of leaf anatomy and essential oils from Drimys brasiliensis Miers in a montane cloud forest in Itamonte, MG, Brazil

“…leaves; however, the authors did not present any differences in the occurrence of these epidermal structures in relation to biotic and abiotic factors. Vieira and Gomes ([ 1995 ]) attributed the function to converge light stimuli for the mesophyll to the papillae of the abaxial epidermis from Psychotria leiocarpa Cham. and Schltdl., P. stenocalyx Müll.…”

Comparison of leaf morphoanatomy of <i>Diodella radula</i> (Willd. &amp; Hoffmanns. Ex Roem. &amp; Schult.) Delprete and <i>D</i><i>iodella teres</i> (Walter) Small (Rubiaceae)

“…However, according to [14] shady plants present sinuous anticlinal walls. But [15] [7], on sunny plants of a dry environment, the epidermal cells, specially on adaxial side, present straight wall and on shady plants, the occurrence of cells with sinuous walls on both sides of the leaf is commonly observed. Although, in front of the revealing, it is verified that variation on cells shape is common, but since both species are sunny plants, it is believed that other factors may influence on this characteristic, such as altitude [16], hydric stress [17] and CO 2 concentration [18]; [19].…”

“…However, as observed on Table 2, papilla size differs significantly on both species; bigger in D. radula The epidermis is papillose on both species, with papilla arranged on the two sides. The papilla presence on abaxial side is uncommon on Rubiaceae family [22], but nevertheless, this was also registered by [23] for P. longepedunculata, [24] for Rustia formosa Klotzsch, [25] for Psychotria tenuinervis and P. stenocalix and [15] for P. leiocarpa, indicating it is a common characteristic for Spermacoceae group. Diodella radula and D. teres presented a significant difference on the papillae size, which may be considered as a diagnostic characteristic so important to separate the two species.…”