Genetic control of flower petal number in Rosa x Damascena Mill f. trigintipetala

We studied the petal number trait in a population obtained after self-pollination of R. x damascena f. trigintipetala following analysis of molecular markers which have previously been mapped near the major dominant locus Blfo/d6 determining this trait in other rose species including R. multiflora and R. hybrida. The results showed that the same genetic mechanism, which determines the petal number trait in R. multiflora and R. hybrida also controls the trait in R. x damascena f. trigintipetala and is related to the dominant effect of a single copy allele in the tetraploid genome of this species. We also analyzed the expression of several flower homeotic genes including R. x damascena APETALA1/FUL-like (paleo AP1 type), R. x damascena euAPETALA 3 (euAP3 line) and R. x damascena AGAMOUS in early stage flower buds corresponding to plants with double and simple flowers. The obtained results showed that only R. x damascena AGAMOUS was differentially expressed between the samples of double and simple flowers, its relative expression being upregulated 3.5-fold in simple flowers. We further cloned and sequenced the four genomic clones of R. x damascena AGAMOUS and studied the potential additive effect of this gene by analysing the segregation of its four alleles in the population of self-pollinated R. x damascena. Analysis of variance of the data for petal number and allele segregation did not show a statistically significant effect of any allele configuration of the AGAMOUS gene on the petal number trait in R. x damascena f. trigintipetala

A Set of Highly Polymorphic Microsatellite Markers for Genetic Diversity Studies in the Genus <i>Origanum</i>

This study reports the development of a set of 20 highly polymorphic genomic SSR markers which can be used for both cultivar identification and genetic diversity studies in several Origanum species, including some of the most popular ones like Greek oregano (Origanum vulgare L. ssp. hirtum), common oregano (O. vulgare L. ssp. vulgare), and sweet marjoram (O. majorana L.). Analysis of the polymorphic information content (PIC) showed an average PIC value of 0.75 with a minimum of 0.41 and a maximum of 0.89, where 17 of the markers showed PIC values above 0.73. Comparative analysis of the genetic diversity of eight natural populations of Greek oregano in Bulgaria showed that six of the genomic SSR markers revealed significantly higher portions of genetic diversity in the populations, compared to 12 EST SSR markers used in our previous study. We also compared the performance of the same six genomic SSR markers with the results for eight SRAP primer combinations, which showed that SRAP markers captured more precisely the genetic structure in natural populations. The developed highly polymorphic genomic SSR markers can be successfully applied to evaluation of the genetic diversity in the genus Origanum, based on the expected and observed heterozygosity in the populations as well as for easy identification of breeding lines and cultivars based on unique SSR fingerprints

Indigenous Yeasts from Rose Oil Distillation Wastewater and Their Capacity for Biotransformation of Phenolics

The indigenous yeasts associated with the spontaneous fermentation of phenolic-rich rose oil distillation wastewater (RODW) generated after the industrial distillation of rose oil were studied. The ITS-rDNA sequence analysis of the samples collected from RODW fermented at semi-sterile conditions, a waste deposition lagoon and endophytic yeasts isolated from industrially cultivated Rosa damascena suggests that the spontaneous RODW fermentation is caused by yeasts from the genus Cyberlindnera found also as endophytes in the rose flowers. Phylogenetic analysis based on the nucleotide sequences of the translation elongation factor (TEF1α) and 18S- and 26S- rRNA genes further confirmed the taxonomic affiliation of the RODW yeast isolates with the genus Cyberlindnera. The RODW fermentation capacity of a selected set of indigenous yeast isolates was studied and compared with those of common yeast strains. The indigenous yeast isolates demonstrated a superior growth rate, resulting in a nearly double reduction in the phenolic content in the fermented RODW. The indigenous yeasts’ fermentation changed the RODW phenolics’ composition. The levels of some particular phenolic glycosides decreased through the depletion and fermentation of their sugar moiety. Hence, the relative abundance of the corresponding aglycons and other phenolic compounds increased. The capacity for the biotransformation of RODW phenolics by indigenous yeasts is discussed

Identification of QTL controlling the ratio of linalool to linalyl acetate in the flowers of Lavandula angustifolia Mill var. Hemus

AbstractThe content of linalyl acetate and the ratio of linalool to linalyl acetate (L/LA ratio) are one of the important parameters that determine the quality of lavender oil. The characterization of a segregating population derived from a self-pollinated Lavandula angustifolia var. Hemus resulted in the identification of a single quantitative trait locus controlling the L/LA ratio (L/LA-QTL) and located on chromosome 8 of the lavender reference genome. The L/LA data analysis demonstrated that plants homozygous for one of the L/LA-QTL alleles had significantly higher linalool content, lower linalyl acetate content and higher L/LA ratio, than the plants which were either heterozygous or homozygous for the other allele. No significant difference was observed for the sum of linalool and linalyl acetate content among these three groups of plants, suggesting that the identified L/LA-QTL is related to an enzyme conversion of linalool to linalyl acetate. The BLAST search revealed that the L/LA-QTL region included a sequence of the LiAAT4 gene of monoterpene acetyltransferase, considered as a candidate gene for the L/LA-QTL locus. Sequence analysis of the LiAAT4 gene of var. Hemus revealed the presence of two alleles differing in two nucleotides and predicted amino acid substitutions. The comparison of the allele configurations of SSR, SRAP and LiAAT4 loci and the L/LA ratio of plants showing recombination in the L/LA-QTL region provided further support that LiAAT4 is a candidate gene underlying the identified L/LA-QTL and controlling the L/LA ratio. The application of molecular markers for the identified L/LA-QTL is discussed

Identification of QTL controlling the ratio of linalool to linalyl acetate in the flowers of <i>Lavandula angustifolia</i> Mill var. Hemus

The content of linalyl acetate and the ratio of linalool to linalyl acetate (L/LA ratio) are one of the important parameters that determine the quality of lavender oil. The characterization of a segregating population derived from a self-pollinated Lavandula angustifolia var. Hemus resulted in the identification of a single quantitative trait locus controlling the L/LA ratio (L/LA-QTL) and located on chromosome 8 of the lavender reference genome. The L/LA data analysis demonstrated that plants homozygous for one of the L/LA-QTL alleles had significantly higher linalool content, lower linalyl acetate content and higher L/LA ratio, than the plants which were either heterozygous or homozygous for the other allele. No significant difference was observed for the sum of linalool and linalyl acetate content among these three groups of plants, suggesting that the identified L/LA-QTL is related to an enzyme conversion of linalool to linalyl acetate. The BLAST search revealed that the L/LA-QTL region included a sequence of the LiAAT4 gene of monoterpene acetyltransferase, considered as a candidate gene for the L/LA-QTL locus. Sequence analysis of the LiAAT4 gene of var. Hemus revealed the presence of two alleles differing in two nucleotides and predicted amino acid substitutions. The comparison of the allele configurations of SSR, SRAP and LiAAT4 loci and the L/LA ratio of plants showing recombination in the L/LA-QTL region provided further support that LiAAT4 is a candidate gene underlying the identified L/LA-QTL and controlling the L/LA ratio. The application of molecular markers for the identified L/LA-QTL is discussed.</p

High cross-pollination rate of Greek oregano (O. vulgare ssp. hirtum) with Common oregano (O. vulgare ssp. vulgare) under open field conditions as revealed by microsatellite marker analysis

AbstractWe studied the mode of pollination in Greek oregano (Origanum vulgare ssp. hirtum) under both controlled and open pollination conditions. When grown indoors without the presence of insects, Greek oregano plants did not develop any seeds, indicating a low level of spontaneous self-pollination. Applying manual self-pollination under the same conditions resulted in only 16 seeds, of which only five were able to germinate. At the same time, a clonally propagated Greek oregano plant of the same genotype produced a rich set of over 300 seeds in open field conditions when the flowers were visited by insects in an area where no other Origanum species were observed. Analysis with SSR markers showed that over 70% of the seeds likely resulted from self-pollination, indicating that insect-mediated pollination is essential for the seed development. We further analyzed the cross-pollination of Greek oregano with Common oregano (O. vulgare ssp. vulgare) in open field conditions where the two subspecies were grown in close proximity. Applying SSR markers, we analyzed 83 plants obtained from seeds of three vegetatively propagated Greek oregano mother plants. Surprisingly, the results showed that all analyzed seedlings resulted from cross-pollination of Greek oregano with Common oregano, indicating that cross-pollination between the two subspecies can completely take over the self-pollination or cross-pollination between the Greek oregano plants. The possible impact of the observed high cross-pollination rate on the genetic origin of seeds of selected Greek oregano lines and varieties, as well as on the genetic diversity and structure of natural populations, is discussed

Mikrovlnný plazmový hořák generovaný v argonu pro povrchovou úpravu malých plodů

Demand for food quality and extended freshness without the use of harmful chemicals has become a major topic over the last decade. New technologies are using UV light, strong electric field, ozone and other reactive agents to decontaminate food surfaces. The low-power non-equilibrium (cold) atmospheric pressure operating plasmas effectively combines all the qualities mentioned above and thus, due to their synergetic influence, promising results in fruit surface decontamination can be obtained. The present paper focuses on the applicability of the recently developed microwave surface wave sustained plasma torch for the treatment of selected small fruit. Optical emission spectroscopy is used for the determination of plasma active particles (radicals, UV light) and plasma parameters during the fruit treatment. The infrared camera images confirm low and fully applicable heating of the treated surface that ensures no fruit quality changes. The detailed study shows that the efficiency of the microbial decontamination of selected fruits naturally contaminated by microorganisms is strongly dependent on the fruit surface shape. The decontamination of the rough strawberry surface seems inefficient using the current configuration, but for smooth berries promising results were obtained. Finally, antioxidant activity measurements demonstrate no changes due to plasma treatment. The results confirm that the MW surface wave sustained discharge is applicable to fruit surface decontamination.Nároky na kvalitu potravin a prodloužení doby jejich čerstvosti bez použití škodlivých chemikálií se v posledním desetiletí stávají důležitým tématem. Nové technologie využívají pro dekontaminaci potravin UV záření, silného elektrického pole, ozónu či jiných reaktivních částic. Nízkoenergetické nerovnovážné (studené) plazma za atmosférického tlaku kombinuje všechny přednosti uvedené výše, proto mohou být při povrchovém ošetření plodů dosaženy slibné výsledky díky jejich synergickému efektu. Tento článek se zaměřuje na aplikaci nedávno vyvinutého mikrovlnného plazmového hořáku s povrchovou vlnou pro ošetření vybraných malých plodů. Pro stanovení reaktivních částic v plazmatu (radikálů, UV záření) a parametrů plazmatu během ošetření plodů je využito optické emisní spektroskopie. Obrázky z infračervené termokamery potvrdily nízkou teplotu ošetřovaného povrchu zabraňující kvalitativním změnám povrchu plodů. Detailní studie ukázala, že účinnost mikrobiální dekontaminace vybraných plodů přirozeně kontaminovaných mikroorganismy je silně závislá na tvaru povrchu plodů. Dekontaminace drsného povrchu jahod byla v současné konfiguraci výboje neefektivní, nicméně pro hladké plody byly získány slibné výsledky. Závěrem testovaná antioxidační aktivita neukázala žádné změny v důsledku působení plazmatu na plody. Výsledky tedy potvrdily, že MW výboj s povrchovou vlnou lze využít pro dekontaminaci povrchu plodů