Topic
Brunsvigia
About: Brunsvigia is a(n) research topic. Over the lifetime, 17 publication(s) have been published within this topic receiving 129 citation(s).
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44 citations
TL;DR: Although B. litoralis plants are long lived, the absence of pollinators in these urban fragments might place populations at an extinction risk.
Abstract: The impacts of habitat fragmentation and reduced population sizes on ecological processes deserve more attention. In this study we examine pollination in rural and urban populations of Brunsvigia litoralis (Amaryllidaceae), an endangered endemic and a flagship species for plant conservation in South Africa. B. litoralis has flowers conforming to the bird-pollination syndrome, but the only flower visitor at the urban sites, the Greater Double-collared Sunbird (Cinnyris afra) (1.6 visits/flower/hour), is unable to access the nectar in the usual way due to a long perianth tube (38.8 mm) and resorts to robbing. Supplemental hand pollination was used to test for pollen limitation of seed set at the urban sites flowers were pollen-supplemented. Seed set in supplemented plants increased by more than an order of magnitude relative to controls. The longer-billed Malachite Sunbird (Nectarinia famosa) was observed as the sole pollinator of B. litoralis at the rural site where seed set was significantly higher. Although B. litoralis plants are long lived, the absence of pollinators in these urban fragments might place populations at an extinction risk.
21 citations
15 citations
TL;DR: Screening for alkaloids produced in four indigenous South African Amaryllidaceae plants, namely, Crinum buphanoides Welw.
Abstract: Screening for alkaloids produced in four indigenous South African Amaryllidaceae plants, namely, Crinum buphanoides Welw. ex Baker, Crinum graminicola I. Verd., Cyrtanthus mackenii Hook. f and Brunsvigia grandiflora Lindl, leads to the isolation of lycorine as the one metabolite produced by all the species studied. C. graminicola produced lycorine in the best yield (2.1 g/kg). Moreover, 1-O-acetyl- and 2-O-acetyl-lycorine, pratorimine, hippadine and tazettine were isolated from C. buphanoides. Haemanthidine, haemanthamine and criwelline were isolated from C. graminicola, while tazettine and 11-hydroxyvittatine were produced by C. mackenii. Finally, crinamine and 11-hydroxyvittatine were isolated from B. grandiflora. This is the very first report on the isolation of these alkaloids from the four South African Amaryllidaceae. Furthermore, some interesting chemosystematic evaluations are reported.
8 citations