Threats to several of the world’s great animal migrations necessitate a research agenda focused on identifying drivers of their population dynamics. The monarch butterfly is an iconic species whose continental migratory population in eastern North America has been declining precipitously. Recent analyses have linked the monarch decline to reduced abundance of milkweed host plants in the USA cau...

The macroscopic and microscopic characters, physical constant values, extractive values, ash values the behaviour of the powerdered drug on treatment with different chemical reagents, microchemical ad histochemical analyses were conducted to characterize some pharmacognostical parameters of Hemidesmus indicus (Linn) R,Br. (Asclepiadaceae).

To determine the degree of compatibility between poly(lactic acid) (PLA) and different biomaterials, PLA was compounded with milkweed fiber, a new crop oil seed. After oil extraction, milkweed remaining cake retained approximately 10% residual oil, 47% protein, and 10% moisture. The fiber (300 lm) was added at 85 : 15 and 70 : 30 PLA : Fiber and blended by extrusion (EX) followed by injection m...

Phenotypic variability results from interactions between genotype and environment is a major driver of ecological evolutionary interactions. Measuring the relative contributions genetic variation, environment, their interaction to phenotypic variation remains fundamental goal ecology.In this study, we assess question: How do local environmental conditions interact influence phenotype within sin...

Theory predicts that plants will increase their defenses against herbivores over time; however, several milkweed defenses have declined as the genus Asclepias has diversified. We review the evolutionary history of milkweed defense and provide new findings from an experiment on 53 Asclepias species. As predicted, monarch performance increased on more recently evolved species, and latex was prima...

The density of corn pollen on leaves of milkweed plants inside and outside of cornfields was measured in several studies from different localities. The purpose was to obtain a representative picture of naturally occurring pollen densities to provide a perspective for laboratory and field studies of monarch larvae feeding on milkweed leaves with Bt corn pollen. Pollen density was highest (averag...

Two stereoisomeric cardenolides, uscharin (1) and a new compound, 2'-epi-uscharin (2), were isolated from the latex of Calotropis gigantea (Asclepiadaceae). Their structures were fully elucidated based on their spectroscopic data, X-ray crystallographic data and chemical evidences. Both epimers (1 and 2) exhibited strong inhibitory effects on HIF-1 activity with different magnitudes. Compound 1...

Asclepias syriaca L. (ASCSY, fam. Apocynaceae) is a weed originating from the northern parts of central, northeastern and southeastern America, as well vicinal areas Canada. The common milkweed was introduced to Europe at beginning 19th century honey, ornamental fiber/silk plant. Today, it occurs in many countries western Central (France, Austria, Czech Republic, Belgium, Germany, Lithuania, Sl...