The effect of anther-derived substances on pollen function was studied using pollen produced by in vitro culture of immature pollen of tobacco (Nicotiana tabacum L.) and petunia (Petunia hybrida). Addition of conditioned medium consisting of diffusates from in situ matured pollen strongly increased pollen germination frequency and pollen tube growth, as well as seed set after in situ pollinatio...

Dioxygenase, Flavonoid Biosynthesis, Flavonols, Genetic Control, Petunia hybrida Soluble enzyme preparations from flower buds of Petunia hybrida catalyzed the conversion of dihydroflavonols to flavonols. Dihydrokaempferol and dihydroquercetin were readily converted to the respective flavonols, whereas dihydromyricetin was a poor substrate. The reaction required 2-oxoglutarate, ascorbate and Fe2...

Peat use in horticulture continues to be scrutinized as consumers are becoming increasingly aware of the environmental sustainability concerns associated with peat. Thus, horticultural industry is driven search for peat alternatives. Substrate stratification (i.e., vertical layering unique media atop another a singular container) has been studied nursery substrates and demonstrated improved res...

Transgenic Petunia plants with a chsA coding sequence under the control of a 35S promoter sometimes lose endogene and transgene chalcone synthase activity and purple flower pigment through posttranscriptional chsA RNA degradation. In these plants, shorter poly(A)+ and poly(A)- chsA RNAs are found, and a 3' end-specific RNA fragment from the endogene is more resistant to degradation. The termini...

Shifts in pollination syndromes involve coordinated changes in multiple floral traits. This raises the question of how plants can cope with rapid changes in pollinator availability by the slow process of accumulation of mutations in multiple genes. Here we study the transition from bee to hawkmoth pollination in the genus Petunia. Interspecific crosses followed by single locus introgressions we...

The petunia rbcS gene SSU301 was introduced into tobacco using Agrobacterium tumefaciens-mediated transformation. The time at which rbcS expression was maximal after transfer of the tobacco plants to the greenhouse was determined. The expression level of the SSO301 gene varied up to 9 fold between individual tobacco plants which had been standardized physiologically as much as possible. The pre...

in this complete random block study we aimed to assess the morphologic reactions of petunia under water deficiency. we used four irrigation treatments (irrigation amount of 25%, 50%, 75%, and 100% of the field's irrigation capacity. the study consisted of 8 repetitions during 6 months in the greenhouse. data were analyzed using spss software, version 12.0 and the mean data were compared with ea...