Dioscorea bulbifera L. is widely distributed in pantropical regions along the equator. The taxonomic treatment of this species is ambiguous due to its extreme polymorphic morphological characters. In order to provide tools to facilitate the study of genetic diversity, population structure, patterns of gene flow, and the mating system of this species, and to assess intraspecific variability and ...

The Dioscoreabuchananii complex is shown to comprise three species, one of which is divided into two subspecies, based on morphological data. Two species, Dioscorearupicola Kunth and Dioscoreamultiloba Kunth, are endemic or subendemic to South Africa and of widespread occurrence in KwaZulu Natal. They differ markedly from each other in inflorescence and floral morphology and appear to be ecolog...

Two new dihydrostemofoline alkaloids, 11(S),12(R)-dihydrostemofoline (3) and stemoburkilline (4), along with stemofoline (1) and 2'-hydroxystemofoline (2) have been isolated from a root extract of Stemona burkillii Prain. The structure and relative configuration of 3 have been determined via spectroscopic data and from comparison with synthetic 11(S),12(S)-dihydrostemofoline (5). The configurat...

When Guinea yam, Dioscorea rotundata Poir, was inoculated with Pratylenchus coffeae and Scutellonema bradys together, there was a 53% suppression of top growth, but when plants were inoculated separately there was a 29% suppression with P. coffeae and a 21% suppression with S. bradys. The reproduction of S. bradys was greatly inhibited when both nematode species were together on the same plant ...

Here we report the whole-genome sequences of three endophytic bacteria, Enterobacter sp. strain DC1, Enterobacter sp. strain DC3, and Enterobacter sp. strain DC4, from root tubers of the yellow yam plant, Dioscorea cayenensis. Preliminary analyses suggest that the genomes of the three bacteria contain genes involved in acetoin and indole-3-acetic acid metabolism.

Yams (Dioscorea spp) in Ghana are important food staples and the most non-traditional export crop contributing to foreign exchange incomes of smallholder producers. Research development over years produced release three improved Dioscorea rotundata varieties 2005. However, adoptions these have been very low. Using cross-sectional data from 544 randomly selected yam farmers employing logit model...

A soil and nematode survey of tomato and yam crops was made in Martinique (French West Indies). Each sample was divided into two parts, one for the nematode study and one for the soil analysis. The coupling of the data was made using the coinertia analysis. For tomato plants, which were grown from seeds, the nematode-soil relationships were very strong. For the two varieties of yams, Dioscorea ...

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Evidence for the microbial degradation of plant saponins is limited to few investigations. Rothrock et al. (1955) have reported that the saponins from Dioscorea tubers can be cleaved into their component parts, diosgenin and the sugar moiety, by Aspergillus terreus. Among the bacteria, yeast, and molds examined, only strains of Penicillium, Aspergillus, and Fusarium were capable of hydrolyzing ...