Metabolic, biochemical and molecular profiling of Catharanthus roseus flower cultivars and transformed hairy roots for monoterpenoid indole alkaloid accumulation /

Catharanthlls rosellS (L.) G Don is a commercially significant flower species and in addition is the only source of the monoterpenoid indole alkaloids (MIA) vinblastine and vincristine, which are key pharmaceutical compounds that are used to combat a number of different cancers. Therefore, procurement of the antineoplastic agents is difficult but essential procedure. Alternatively, CatharanthllS tissue cultures have been investigated as a source of these agents; however they do not produce vindoline, which is an obligate precursor to vinblastine and vincristine. The interest in developing high MIA cultivars of Catharantlws rosellS has prompted metabolic profiling studies to determine the variability of MIA accumulation of existing flowering cultivars, with particular focus on the vindoline component ofthe pathway. Metabolic profiling studies that used high performance liquid chromatography of MIAs from seedlings and young leaf extracts from 50 different flowering cultivars showed that, except for a single low vindoline cultivar (Vinca Mediterranean DP Orchid), they all accumulate similar levels of MIAs. Further enzymatic studies with extracts from young leaves and from developing seedlings showed that the low vindoline cultivar has a IO-fold lower tabersonine-16-hydroxylase activity than those of CatharanthllS rosellS cv Little Delicata. Additionally, studies aimed at metabolic engineering ofvindoline bios}l1thesis in Catharanthus rosellS hairy root cultures have been performed by expressing the last step in vindoline biosynthesis [Dcacetylvindoline-4-0- acetyltransferase (DAT)]. Enzymatic profiling studies with transformed hairy roots have confirmed that over-expressing DAT leads to lines with high levels of O-acetyltransferase activity when compared to non-expressing hairy roots. One particular DA T over111 expressing hairy root culture (line 7) contained 200 times the OAT activity than leaves of control lines. Additional MIA analyses revealed that DAT over-expressing hairy roots have an altered alkaloid profile with significant variation in the accumulation of h6rhammericine. Further analysis of transformed hairy root line 7 suggests a correlation between the expression of OAT activity and h6rhammericine accumulation with root maturation. These studies show that metabolic and selective enzymatic profiling can enhance our ability to search for relevant MIA pathway mutants and that genetic engineering with appropriate pathway genes shows promise as a tool to modify the MIA profile of Catharanthus roseus.

Adult perceptions of student involvement in schoolyard gardening /

The purpose of this research is to investigate through adult perceptions what factors have enabled and limited student participation in schoolyard gardening, and how to support student involvement in schoolyard gardening. It is a collective case study of three schools in the Toronto District School Board (TDSB, Ontario, Canada) that are currently running a schoolyard gardening project. Sixteen interviews were conducted during May and June, 2005, and photos of the three schoolyard gardens were taken. The results show that the common factors that have enabled student participation in schoolyard gardening at the three schools are teacher's initiative and commitment, principal's leadership and support, parental involvement and donations, and the TDSB's EcoSchools program and workshops. The common limiting factors are time, money, and the unions' "work-to-rule" issue. The ways to support student involvement include teachers integrating the gardening into the curriculum; parents making donations to the school and creating a family gardening culture; principals supporting in money or budget and taking the lead; the TDSB providing funding, awards, incentives, and more maintenance; and the Ontario Ministry of Education supplying funding, curriculum link, and teacher training.

Niagara Parks Commission School of Gardening Graduation Program, 1956

The Niagara Parks Commission School of Gardening was organized in 1935 in order to help fill the Commission’s need for skilled gardeners to maintain the extensive parkland owned by the Commission. In 1959 the School was renamed the Niagara Parks Commission School of Horticulture. The name changed again in 1990 to the Niagara Parks Botanical Gardens and School of Horticulture to better reflect the development of the program.

Novel glutathione disulfide transferase function of CC-glutaredoxins involved in disease resistance and flower development

Glutaredoxins are oxidoreductases capable of reducing protein disulfide bridges and glutathione mixed disulfides through the process of deglutathionylation and glutathionylation. Lately, redox-mediated modifications of functional cysteine residues of TGA1 and TGA8 transcription factors have been postulated. Namely, GRX480 and ROXY1 glutaredoxins have been previously shown to interact with TGA proteins and have been suggested to regulate redox state of these proteins. TGA1, together with TGA2, is involved in systemic acquired resistance (SAR) establishment in the plant Arabidopsis thaliana through PR1 (Pathogenesis related 1) gene activation. They both form an enhanceosome complex with the NPR1 protein (non-expressor of pathogenesis related gene 1) which leads to PR1 transcription. Although TGA1 is capable of activating PR1 transcription, the ability of the TGA1 NPR1 enhanceosome complex to assembly is based on the redox status of TGA1. We identified GRX480 as a glutathionylating enzyme that catalyzes the TGA1 glutathione disulfide transferase reaction with a Km of around 20μM GSSG (oxidized glutathione). Out of four cysteine residues found within TGA1, C172 and C266 were found to be glutathionylated by this enzyme. We also confirmed TGA1 glutathionylation in vivo and showed that this modification takes place while TGA1 is associated with the PR1 promoter enzymatically via GRX480. Furthermore, we show that glutathionylation via GRX480 abolishes TGA1's interaction with NPR1 and consequently prevents the TGA1-NPR1 transcription activation of PR1. When glutathionylated, TGA1 is recruited to the PR1 promoter and acts as a repressor. Therefore, glutathionylation is a mechanism that prevents TGA1 NPR1 interaction, allowing TGA1 to function as a repressor of PR1 transcription. Surprisingly, GRX480 was not able to deglutathionylate proteins demonstrating the irreversible nature of the reaction. Moreover, we demonstrate that other members of CC-class glutaredoxins, namely ROXY1 and ROXY2, can also catalyze protein glutathionylation. The TGA8 protein was previously shown to interact with NPR1 analogs, BOP1 and BOP2 proteins. However, unlike the case of TGA1 NPR1 interaction, here we demonstrate that TGA8-BOP1 interaction is not redox regulated and that TGA8 glutathionylation by ROXY1 and ROXY2 enzymes does not abolish this interaction in vitro. However, TGA8 glutathionylation results in TGA8 oligomer disassembly into smaller complexes and monomers. Our results suggest that CC-Grxs are unable to reduce mixed disulfides, instead they efficiently catalyze the opposite reaction which distinguishes them from traditional glutaredoxins. Therefore, they should not be classified as glutaredoxins but as protein glutathione disulfide transferases.

Place Card - Girl in Blue Dress with Flower

A place card with an illustration of a girl in a blue dress and red flowers.

Place Card - Girl in Green Dress with Flower

A place card with an illustration of a girl in a green dress and red flowers.

Isolation, Stabilization and Characterization of Xanthophyll from Marigold Flower- Tagetes Erecta-L

The present paper deals with the chemistry, isolation, separation, characterisation and stabilisation of the Marigold oleoresin and its application as a natural food colorant. Marigold (Tagetes Erecta L), an ornamental plant belonging to the composite family, has a rich source of natural antioxidant-Lutein. A natural pigment, xanthophylls offer an alternative to synthetic dyes as a food colorant, due to its non-toxicity. Chromatographic separations of saponified and unsaponified oleoresin were performed and Trans-Lutein identified as the major constituent. Well-preserved flowers exhibit a high yield of Xanthophyll content (105.19 g/Kg) in contrast to the unpreserved flower sample (54.87 g/Kg), emphasizing the significance of flower preservation in the extraction of xanthophyll. The stability and amount of xanthophyll also increased from 105.19 g/Kg to 226.88 g/Kg on saponification and subsequent purification with Ethylene Dichloride

The status and barriers to the implementation and continuation of the school gardening projects in Germany, Nigeria and the United States of America

In drawing a conclusion for this study, care must be taken in generalizing findings since the population of students and teachers investigated were limited to certain levels in the different schools and countries. This study recognized some complexity of the factors underlying the status of school gardening instruction and activities in Germany, Nigeria and the U.S. as inadequate time for decision-making in the process of gardening, motivation of teachers and students. This was seen as the major impediments that influenced the status of gardening in the three countries. However, these factors were considered to have affected students’ mode of participation in the school gardening projects. This research finding suggests that the promotion and encouragement of students in gardening activities will promote vegetable production and increasing the numbers of practical farmers. Gardening has the potential to create opportunities for learning in an environment where children are able to experience nature first hand and to use the shared experience for communication (Bowker & Tearle, 2007). Therefore, the need for students to be encouraged to participate in gardening programs as the benefit will not only reduce the rate of obesity currently spreading among youths, but will contribute to the improve knowledge on science subjects. To build a network between community, parents and schools, a parent’s community approach should be used as the curriculum. The community approach will tighten the link between schools; community members, parents, teachers and students. This will help facilitate a better gardening projects implementation. Through a close collaboration, teachers and students will be able to identify issues affecting communities and undertake action learning in collaboration with community organizations to assess community needs and plan the implementation strategies as parents are part of the community. The sense of efficacy is a central factor in motivational and learning processes that govern educational improvement, standard and performance on complex tasks of both teachers and students. Dedication and willingness are the major stimulator and achievement of a project. Through a stimulator and provision of incentives and facilities, schools can achieve the best in project development. Teachers and principals should be aware that students are the lever for achieving the set goals in schools. Failure to understand what students need will result in achieving zero result. Therefore, it is advised that schools focus more on how to lure students to work through proper collaboration with the parents and community members. Principals and teachers should identify areas where students need to be corrected, helping them to correct the problem will enable them be committed in the schools’ programs.

Fran's flower.

Con breve narrativa se explica un concepto difícil para un niño, que para obtener un buen resultado hay que emplear los medios adecuados y tener la paciencia necesaria. Una niña encuentra una maceta llena de tierra y un pequeño brote verde. Todos los días la alimenta con sus comidas favoritas, pizza, hamburguesa con queso, espagueti, galletas de chispas de chocolate, fresa y helado. Pero el brote no crece y ella lo tira. Allí, con la lluvia y el sol, la pequeña planta comienza a crecer y un día Fran tiene una gran sorpresa. También descubre que una comida apropiada para una niña no es necesariamente una comida adecuada para una flor. Para niños en edad preescolar.

Effect of Community of Residence on Neurobehavioral Development in Infants and Young Children in a Flower-Growing Region of Ecuador

In this study we compared neurobehavioral development in Ecuadoran children living in two communities with high potential for exposure to organophosphate (OP) and carbamate pesticides to that of children living in a community with low potential for exposure. Residence in communities with high potential for exposure to OP and carbamate pesticides was associated with poorer neurobehavioral development of the child even after controlling for major determinants of delayed development. Malnourished populations may be particularly vulnerable to neurobehavioral effects of pesticide exposure.

Organic farming in isolated landscapes does not benefit flower-visiting insects and pollination

Organic farming has often been found to provide benefits for biodiversity, but the benefits can depend on the species considered and characteristics of the surrounding landscape. In an intensively farmed area of Northeast Italy we investigated whether isolated organic farms, in a conventionally farmed landscape, provided local benefits for insect pollinators and pollination services. We quantified the relative effects of local management (i.e. the farm system), landscape management (proportion of surrounding uncultivated land) and interactions between them. We compared six organic and six conventional vine fields. The proportion of surrounding uncultivated land was calculated for each site at radii of 200, 500, 1000 and 2000 m. The organic fields did not differ from the conventional in their floral resources or proportion of surrounding uncultivated land. Data were collected on pollinator abundance and species richness, visitation rates to, and pollination of experimental potted plants. None of these factors were significantly affected by the farming system. The abundance of visits to the potted plants in the conventional fields tended to be negatively affected by the proportion of surrounding uncultivated land. The proportion fruit set, weight of seeds per plant and seed weight in conventional and organic fields were all negatively affected by the proportion of surrounding uncultivated land. In vine fields the impact of the surrounding landscape was stronger than the local management. Enhancement of biodiversity through organic farming should not be assumed to be ubiquitous, as potential benefits may be offset by the crop type, organicmanagement practices and the specific habitat requirements in the surrounding landscape.

Effects of patch size and density on flower visitation and seed set of wild plants: a pan-European approach

1. Habitat fragmentation can affect pollinator and plant population structure in terms of species composition, abundance, area covered and density of flowering plants. This, in turn, may affect pollinator visitation frequency, pollen deposition, seed set and plant fitness. 2. A reduction in the quantity of flower visits can be coupled with a reduction in the quality of pollination service and hence the plants’ overall reproductive success and long-term survival. Understanding the relationship between plant population size and⁄ or isolation and pollination limitation is of fundamental importance for plant conservation. 3. Weexamined flower visitation and seed set of 10 different plant species fromfive European countries to investigate the general effects of plant populations size and density, both within (patch level) and between populations (population level), on seed set and pollination limitation. 4. Wefound evidence that the effects of area and density of flowering plant assemblages were generally more pronounced at the patch level than at the population level. We also found that patch and population level together influenced flower visitation and seed set, and the latter increased with increasing patch area and density, but this effect was only apparent in small populations. 5. Synthesis. By using an extensive pan-European data set on flower visitation and seed set we have identified a general pattern in the interplay between the attractiveness of flowering plant patches for pollinators and density dependence of flower visitation, and also a strong plant species-specific response to habitat fragmentation effects. This can guide efforts to conserve plant–pollinator interactions, ecosystem functioning and plant fitness in fragmented habitats.

Glucosinolate-accumulating S-cells in Arabidopsis leaves and flower stalks undergo programmed cell death at early stages of differentiation

Plant secondary metabolites glucosinolates (GSL) have important functions in plant resistance to herbivores and pathogens. We identified all major GSL that are accumulated in S-cells in Arabidopsis by MALDI-TOF MS, and estimated by LC-MS that the total GSL concentration in these cells is above 130 mM. The precise locations of the S-cells outside phloem bundles in rosette and cauline leaves and in flower stalks were visualised using sulphur mapping by cryo-SEM/EDX. S-cells contain up to 40% of total sulphur in flower stalk tissues. S-cells in emerging flower stalks and developing leaf tissues show typical signs of Programmed Cell Death (PCD) or apoptosis, such as chromatin condensation in the nucleus and blebbing of the membranes. TUNEL staining for DNA double strand breaks confirmed PCD in S-cells in postmeristematic tissues in the flower stalk as well as in the leaf. Our results show that S-cells in postmeristematic tissues proceed to an extreme degree of metabolic specialisation besides PCD. Accumulation and maintenance of a high concentration of GSL in these cells are accompanied by degradation of a number of cell organelles. The substantial changes in the cell composition during S-cell differentiation indicate the importance of this particular GSL-based phloem defence system. The specific anatomy of the S-cells and ability to accumulate specialised secondary metabolites is similar to that of the non-articulated laticifer cells in latex plants and thus indicates a common evolutionary origin.