Structure and development of fruits and seeds of weed species of Euphorbiaceae

Abstract

ABSTRACT(Structure and development of fruits and seeds of weed species of Euphorbiaceae). Euphorbiaceae s.l. presents several morphological types of fruits, of which the schizocarp is the most common. Th e fruits of weed species of Euphorbia graminea Jacq., Euphorbia heterophylla L., Euphorbia hirta L. (= Chamaesyce hirta (L.) Millsp.) and Euphorbia prostrata Aiton (= Chamaesyce prostrata (Aiton) Small) are objects of this study. Infl orescences and fruits in development were collected on the campus of the State University of Maringa (UEM), Brazil, fi xed in FAA 50 and glutaraldehyde, dehydrated and sectioned with a rotary microtome according to standard morphology and anatomy techniques. Th e species present several anatomical similarities, though there are some diff erences related to the outer epidermis of the ovaries, which is glabrous in E. graminea and hairy in the other species. Th e ripe fruits present a papilose exocarp and lack trichomes, except for E. hirta. Th e ovules are anatropous, bitegmic and crassinucellate; the seeds are exotegmic and the embryos are straight.

Floral morphology and anatomy of Dalechampia alata Klotzsch ex Baill. (Euphorbiaceae), with emphasis on secretory structures

“…This same pattern was observed in D. stipulacea (Silva and Souza, 2009;Souza et al, 2010) and Euphorbia species (Gagliardi et al, 2012). According to Roth (1977) the inner epidermis of the carpel is able to keep its meristematic activity for a long time resulting in a conspicuous multilayered epidermis.…”

“…Besides Dalechampia and Euphorbia, this process has been reported within Euphorbiaceae in Manihot (Oliveira and Oliveira, 2009), in which it results in the formation of subadaxial and adaxial meristems that produces the mesocarp and the endocarp, respectively. Meristematic activity of the inner epidermis of the ovary is also reported in Rutaceae and Fabaceae, however, instead of two meristems as in Euphorbiaceae, they present only one, either in subepidermal layers or in the inner epidermis itself (Roth, 1977;Souza et al, 2003;Gagliardi et al, 2012).…”

Anatomical Characteristics of Stem and Leaf in <i>Euphorbia hirta</i> L.

“…The epidermis, the stomata and the venation patterns have been investigated in E. hirta [2]. Structure and development of fruits and seeds of weed species E. hirta have been stated [7]. The presence of lignified xylem vessel, anomocytic type of stomata was observed in leaf [1].…”

Embriologia de Pera glabrata (Schott) Poepp. ex Baill. (Peraceae, Malpighiales)

“…Em Pera glabrata, a porção mais interna do mesocarpo possui dois conjuntos de esquerênquima dispostos perpendicularmente entre si. Em Euphorbiaceae, são observados três conjuntos de esclerênquima dispostos em três sentidos diferentes (Toledo 1936, Oliveira e Oliveira 2009, Silva e Souza 2009, Gagliardi et al 2012, Gagliardi et al 2014. Não há divisão da epiderme interna do ovário durante a formação do fruto de Pera glabrata e o endocarpo é composto por uma camada de células não lignificadas.…”