Cotton leaf, bract, fibre from opened bolls, and soil samples were collected weekly during two growing seasons (1984, 1985). Total and Gram negative bacterial populations were determined for each sample. Representative bacterial isolates were identified and endotoxin concentrations determined. For both years total and Gram negative bacterial populations on all sample types remained relatively s...

BACKGROUND AND AIMS Most species of Dalechampia vines (Euphorbiaceae) attract bee pollinators with terpenoid resins secreted by a gland-like structure in the inflorescence. In some species, pollinating bees appear to preferentially visit inflorescences (blossoms) with large resin-producing glands, whereas in other species bees preferentially visit blossoms with large involucral bracts. In this ...

Podostemaceae (the river weeds) are ecologically and morphologically unusual angiosperms. The subfamily Tristichoideae has typical shoot apical meristems (SAMs) that produce leaves, but Podostemoideae is devoid of SAMs and new leaves arise below the base of older leaves. To reveal the genetic basis for the evolution of novel shoot organogenesis in Podostemaceae, we examined the expression patte...

Previously, the identification of fossil Pseudolarix at the species level has been based on the morphology of the bract-scale complex of the seed cone. The morphological consistence of fossils through most of the Cenozoic with extant P. amabilis has led them to be considered conspecific, suggesting that P. amabilis is an extraordinary example of morphological stasis. However, the lack of cuticu...

Crude and purified aqueous extracts of cotton bracts shown to cause airway constriction in naive subjects were assayed for endotoxin content. Pulmonary function measured by flow changes on partial expiratory flow volume curves was used to assess airway responses to the bract extracts after their inhalation by a panel of volunteers. These responses are similar to the acute responses experienced ...

Extreme modification and reduction in floral morphology presents an obstacle to determining the evolutionary relationships and homologies of the holoparasites in Balanophoraceae. Developing flowers and inflorescences of two dioecious species, Balanophora papuana and B. elongata, were compared to each other and to the monoecious B. fungosa. Intermingled with flowers in the male inflorescences ar...

This review is an attempt to analyze possible ways of bractless infl orescence formation in Cruciferae. Function of genes which are supposed to play a certain role in a process of bract reduction/development – LFY, AP1, AP2, BOP1, BOP2, JAG, FUL/AGL8, SOC1/AGL20, BRA – is discussed with concentration on the structure of fl owers and infl orescences, based on the results of genetic analysis (inc...

We have created transgenic Arabidopsis plants in which a gene encoding the cell-autonomous diphtheria toxin A chain (DT-A) was expressed under the control of the LEAFY (LFY) promoter. This promoter is active both in emerging leaf primordia and young flowers, with the highest activity in flowers. The majority of LFY::DT-A plants had normal vegetative development but lacked flowers, demonstrating...

Hedychium putaoense Y.H. Tan & H.B. Ding, a new species of Zingiberaceae from Putao, Kachin state, Northern Myanmar, is described and illustrated. It is similar to H. densiflorum Wall. and H. longipedunculatum A.R.K. Sastry & D.M. Verma, but differs by its very small bract (4-6 × 2.5-3 mm vs. 18-19 × 5-5.5 mm and ca. 11 × 7 mm, respectively), semicircle and dark red bracteole, orange flower and...

Selected physiological and biochemical parameters were monitored at the vegetative and reproductive growth stages in potted Bougainvillea plants treated with five different concentrations of TRIA. Advanced flowering, flower bud number, and blooming rate increased significantly with 0.5 and 1.0 mg/L TRIA treatments. Similarly, photosynthetic rate, pigment content, quantum yield, and stomatal con...