BACKGROUND Measuring genome size by flow cytometry assumes direct proportionality between nuclear DNA staining and DNA amount. By 1997 it was recognized that secondary metabolites may affect DNA staining, thereby causing inaccuracy. Here experiments are reported with poinsettia (Euphorbia pulcherrima) with green leaves and red bracts rich in phenolics. METHODS DNA content was estimated as flu...

Saururus chinensis is a core member of Saururaceae, a perianthless (lacking petals or sepals) family. Due to its basal phylogenetic position and unusual floral composition, study of this plant family is important for understanding the origin and evolution of perianthless flowers and petaloid bracts among angiosperm species. To isolate genes involved in S. chinensis flower development, subtracte...

Hitherto characters derived mostly from macromorphology were used to distinguish among the members of Acanthopsis Harv., a taxonomically difficult group plants endemic arid parts southern Africa. The taxonomic significance leaf and bract indumentum in was investigated using light, scanning electron microscopy. Five non-glandular three glandular trichome types distinguished on leaves floral brac...

This study looked at the best conditions for extracting bioactive compounds from globe artichoke (Cynara cardunculus var. scolymus), such as total phenolics, flavonoids, ascorbic acid, and inulin. The obtained results showed that optimum extraction of phenolics flavonoids receptacle bracts artichoke, when applying maceration room temperature, with 70% methanol 4 h. Genstin was major phenolic co...

Dysaster cajamarcensis is a spreading broad-leaved shrub named as a new genus and species of the tribe Astereae subtribe Hinterhuberinae collected in northern Peru. It has bisexual disc florets, disc style branches with strong stigmatic lines and hairy appendages, compressed achenes in both ray and disc florets, and papyraceous involucral bracts.

A new species of Moraceae is described, illustrated and compared to its close morphological relatives. Dorstenia triseriata presents similarities with Dorstenia turnerifolia but distinguished by size of peduncle, diameter of receptacle, number of bract rows, color of marginal bracts, and by an indistinct fringe on inflorescence. A conservation assessment based on IUCN criteria determines the ne...

Based on morphology and molecular data, a new species Semenovia gyirongensis Q.Y.Xiao & X.J.He, from Gyirong County, Xizang, China, is described and illustrated. It is morphologically most similar to S. malcolmii (Hemsley & Pearson) Pimenov, but differs in its cylindric much-branched root, intensively branching long underground caudex with distinct nodes, narrowly ovate to ovate terminal leaf l...

It is commonly assumed that the dead, hardened floral bracts of the dispersal unit of grasses have been evolved to protect seeds from predation and / or assist in fruit/caryopsis dispersal. While these structures have important agronomical and economical implications, their adaptive value has not been fully explored. We investigated the hypothesis that the maternally derived hardened floral bra...

Inflorescence development of the 'Hass' avocado (Persea americana Mill.) was investigated at the macro and microscopic level. Near the end of shoot extension, two secondary axis meristems were present in the axils of inflorescence bracts. The primary axis meristem changed shape from conical to flattened to conical followed by the initiation of additional bracts and associated secondary axis inf...

The bacterial content of specially treated cottons used by other investigators to test human pulmonary responses to cotton dust was examined. Cotton from Lubbock, Tex. and Stoneville, Miss. were either (i) harvested by machine and handled as commercial bale cotton, (ii) harvested as closed bolls with bracts intact and opened under special conditions, (iii) harvested as closed bolls, with bracts...