Plant death is the most common effect resulting from the application of glyphosate, the active ingredient in the herbicide Roundup1. Individual seedlings of the morning glory, Ipomoea purpurea L. Roth, however, have been shown to exhibit tolerance to glyphosate, surviving after what should have been a lethal dose. Those that grow and reach reproductive maturity often exhibit deformed anthers wi...

Aims Floral traits are frequently used in traditional plant systematics because of their assumed constancy. One potential reason for the apparent constancy of flower size is that effective pollen transfer between flowers depends on the accuracy of the physical fit between the flower and pollinator. Therefore, flowers are likely to be under stronger stabilizing selection for uniform size than ve...

Naive bumblebee foragers appear to use movement rules at small spatial and temporal scales, but it is not clear whether these rules determine movement patterns as the scales increase. One strategy for efficient foraging used by bumblebees is near-far search, involving short flights when in good patches of flowers and longer flights when in poor patches. Bumblebees also demonstrate the use of a ...

Some Malpighiaceae produce minute cleistogamous flowers in addition to showy chasmogamous flowers. Standard techniques fail to reveal how the cleistogamous flowers achieve self-fertilization. Fluorescence in longitudinal sections shows that the pollen germinates inside the indehiscent anther. The pollen tubes then grow down through the filament,. into the receptacle, up into the carpels, and in...

We tested a hypothesis originating with Darwin that bees outside the nest exhibit social learning in flower choices. Naive bumblebees, Bombus impatiens, were allowed to observe trained bees or artificial bees forage from orange or green flowers. Subsequently, observers of bees on green flowers landed more often on green flowers than non-observing controls or observers of models on orange flower...

THE PURPOSE OF THIS STUDY WAS THE QUALITATIVE AND QUANTITATIVE ANALYSIS OF FLAVONOIDS FROM ROBINIA PSEUDOACACIA USING TWO DIFFERENT TECHNIQUES OF ANALYSIS: Thin Layer Chromatography (TLC) and TLC coupled with photo-densitometry. The results obtained by chromatographic analysis showed a higher concentration of flavonoids in flowers than in leaves. The flowers harvested in the plains have a highe...

BACKGROUND AND AIMS Variation in the relative female and male reproductive success of flowering plants is widespread, despite the fundamental hermaphroditic condition of the majority of species. In many hermaphroditic populations, environmental conditions and their influence on development and size can influence the gender expression of individuals through the formation of hermaphroditic and un...

Leaf yellowing or petal senescence is the main postharvest disorder for many cut flowers. Plant hormones such as cytokinins are able to inhibit leaf yellowing in some cut flowers and potted plants. In our experiments, we applied thidiazuron aiming to delay leaf yellowing and 1-methylciclopropene (1-MCP) for inhibiting flower senescence of cut stock flowers during vase life. Cut flowers were pul...

BACKGROUND Recently, tea (Camellia sinensis) flowers have attracted increasing interest because of their content of bioactive compounds such as catechins. The aim of this study was to investigate the occurrence of some characteristic compounds in tea flowers. RESULTS A principal component analysis of metabolites using ultra-performance liquid chromatography/time-of-flight mass spectrometry sh...

Three genes encoding anthocyanidin reductase (ANR) in apple (Malus×domestica Borkh.), designated MdANR1, MdANR2a, and MdANR2b, have been cloned and characterized. MdANR1 shows 91% identity in coding DNA sequences with MdANR2a and MdANR2b, while MdANR2a and MdANR2b are allelic and share 99% nucleotide sequence identity in the coding region. MdANR1 and MdANR2 genes are located on linkage groups 1...