Anatomy of the Dicotyledons.
About: This article is published in American Midland Naturalist.The article was published on 1950-11-01. It has received 2511 citations till now.
Citations
More filters
TL;DR: Morphological and anatomical evidence is presented for recognizing the generic status of the two American species of Juglandaceae with winged fruits E. mexicana and Alfaroa costaricensis.
Abstract: Morphological and anatomical evidence is presented for recognizing the generic status of the two American species of Juglandaceae with winged fruits. Oreomunnea pterocarpa is endemic to Costa Rica, while 0. mexicana ranges from Mexico to Costa Rica. Enlgelhardia nicaraguensis Molina is reduced to synonymy under 0. nmexicana subsp. mexicana, and 0. mexicana subsp. costaricensis is described as new. Information is provided on the geographic range, general ecology, morphology, and taxonomy of the American taxa. The somatic count of 2n = 32 for 0. mexicana subsp. mexicana is the first report for the genus. The New World species of Juglandaceae with winged fruits form an alliance that is recognized by some as the genus Oreomunnea (Hjelmqvist, 1948; Leroy, 1951, 1955) and by others as a section of the predominantly Old World genus Engelhardia (Candolle, 1914; Nagel, 1914; Standley, 1927a; Manning, 1949, 1959). While four Central American species have been described to date, the paucity of collections, particularly fertile ones, has handicapped critical taxonomic evaluations. Oreomunnea pterocarpa Oersted (1856), for example, is represented today by fewer than fifteen flowering and fruiting specimens. And until recently no fruits of Engelhardia mexicana Standley (1927a) had been collected since Rovirosa roamed Chiapas, Mexico, in 1891. Engelhardia nicaraguensis Molina (1968) is based on two fruiting specimens, but again no information was made available on the important floral characteristics. The fourth species was described by Standley (1940) as E. guatemalensis on the basis of several sterile collections, but as Manning (1959) has since pointed out some of the specimens have proved to be E. mexicana and Alfaroa costaricensis. The residue of Standley's E. guatemalensis is by no means well understood. According to Manning (1959) it ... . might not be distinct from Alfaroa manningii, A. hondurensis, or Engelhardtia pterocarpa." Fortunately, this puzzle now seems to have been resolved by the discovery of fruiting material at the type locality. Engelhardtia guatemalensis Standley is in reality an Alfaroa, apparently related most closely to A. hondurensis (Williams &
33 citations
TL;DR: This work investigated another approach to infect Theobroma cacao with a greater-than-unit length copy of the CSSV DNA genome cloned into the Agrobacterium binary vector pBin19 and was transferred into young plants via Agrobacteria tumefaciens.
Abstract: Cacao swollen shoot virus (CSSV) is a small non-enveloped bacilliform virus with a double-stranded DNA genome. A very restricted host range and difficulties in transmitting the virus, either mechanically or via its natural vector, have hindered the study of cacao swollen shoot disease. As an alternative to the particle-bombardment method previously reported, we investigated another approach to infect Theobroma cacao. A greater-than-unit length copy (1.2) of the CSSV DNA genome was cloned into the Agrobacterium binary vector pBin19 and was transferred into young plants via Agrobacterium tumefaciens. Typical leaf symptoms and stem swelling were observed seven and eleven weeks post inoculation, respectively. Viral DNA, CSSV coat protein and virions were detected in leaves with symptoms. Agroinfected plants were used to study the in situ localization of CSSV and its histopathologic effects in planta. In both leaves and petioles, virions were only seen in the cytoplasm of phloem companion cells and of a few xylem parenchyma cells. Light microscopy showed that stem swelling results from a proliferation of the xylem, phloem and cortex cells.
33 citations
TL;DR: The findings of this study show that BnCLIP1 encodes a lipase, localizes at the MCSs and involves in chloroplast development.
Abstract: Background
Fatty acids synthesized in chloroplast are transported to endoplasmic reticulum (ER) for triacylglycerols (TAGs) resembling. The development of chloroplast also requires lipids trafficking from ER to chloroplast. The membrane contact sites (MCSs) between ER and chloroplast has been demonstrated to be involved for the trafficking of lipids and proteins. Lipids trafficking between ER and chloroplast is often accompanied by lipids interconversion. However, it is rarely known how lipids interconversion happens during their trafficking.
33 citations
Cites background from "Anatomy of the Dicotyledons."
...Lipid bodies were considered to be located in the mesophyll tissue of leaves [10,11] until the middle of the last century....
[...]
TL;DR: A total of 27 taxa from the families Adoxaceae s.lat.
32 citations
TL;DR: In this paper, a morphologically based phylogenetic analysis of Gunnera is presented, with Saxifragaceae s.I.str.str as the closest sister group.
Abstract: I. Abstract Cladistic and phenetic analyses of leaf and other morphological characters of Gunnera strongly support monophyly of the genus, with the Saxifragaceae s.str. as the closest sister group. This morphologically based phylogeny provides a more coherent understanding of the evolutionary history of Gunnera than do recent phylogenetic hypotheses based on genetic data sets with Myrothamnaceae as the sister group. Simple, crenate, palinactinodromously veined leaves lacking freely ending veinlets and tricolpate, tectate-perforate pollen with a reticulate exine indicate a shared ancestry. Within the genus Gunnera all six traditionally recognized subgenera are monophyletic, as supported by leaf architectural apomorphies. The monotypic subgenus Ostenigunnera is the sister group to the other five subgenera, which can be divided into two principal lineages. One lineage includes the subgenera Milligania and Misandra, characterized by a prostate stoloniferous habit with small, low-rank leaves and exclusively un...
32 citations