Effect of GA 3 and paclobutrazol on adventitious shoot regeneration of two Pelargonium sp

This study had two aims. The first was to improve the regeneration efficiency of Pelargonium leaf discs by adventitious budding. The second was to test the effect of gibberellic acid (GA 3) and paclobutrazol (PBZ) on callus formation and adventitious shoot regeneration in Pelargonium before using genetic transformation of this species for functional validation of genes involved in the process of GA regulation. GA 3 and paclobutrazol (an inhibitor of GA synthesis pathway) were added (together or separately) in the shoot regeneration media of two Pelargonium species, Pelargonium * hortorum \u27Panache sud\u27 (\u27P.sud\u27) and Pelargonium * domesticum \u27Autumn haze\u27 (\u27 P.dom\u27). In both cases, GA 3 applied alone, completely inhibited the bud regeneration. Moreover, the rate of callus formation decreased drastically when 5 M of GA 3 was applied to \u27 P. dom\u27 explants. Similar result was obtained with \u27P.sud\u27 explants using 20 M GA 3. Paclobutrazol (0.3 M) applied at the same time as GA 3 (10 M) could partially restore regeneration process of \u27 P. dom\u27. For \u27 P. dom\u27, the use of paclobutrazol alone increased callus formation and slightly improved the rate of regeneration. Moreover, initiated buds had a better appearance. For \u27P. sud\u27, which had an abundant callusing, paclobutrazol did not improve regeneration and led to hyperhydric shoots

Overexpression of RoDELLA impacts the height, branching, and flowering behaviour of Pelargonium × domesticum transgenic plants

Key message We reported the cloning of a rose DELLA gene. We obtained transgenic Pelargonium lines overexpressing this gene which presented several phenotypes in plant growth, root growth, flowering time and number of inflorescences. Abstract Control of development is an important issue for production of ornamental plant. The plant growth regulator, gibberellins (GAs), plays a pivotal role in regulating plant growth and development. DELLA proteins are nuclear negative regulator of GA signalling. Our objective was to study the role of GA in the plant architecture and in the blooming of ornamentals. We cloned a rose DELLA homologous gene, RoDELLA, and studied its function by genetic transformation of pelargonium. Several transgenic pelargonium (Pelargonium × domesticum ‘Autum Haze’) lines were produced that ectopically expressed RoDELLA under the control of the 35S promoter. These transgenic plants exhibited a range of phenotypes which could be related to the reduction in GA response. Most of transgenic plants showed reduced growth associated to an increase of the node and branch number. Moreover, overexpression of RoDELLA blocked or delayed flowering in transgenic pelargonium and exhibited defects in the root formation. We demonstrated that pelargonium could be used to validate ornamental gene as the rose DELLA gene. RoDELLA overexpression modified many aspects of plant developmental pathways, as the plant growth, the transition of vegetative to floral stage and the ability of rooting

Mise en place d'une expérience avec le grand public: entre recherche, vulgarisation et pédagogie

Methodological considerations on implementing a participative experimentWe present the implementation of an economic experiment conducted simultaneously in 11 French cities, with over 2700 participants, during four uninterrupted hours, during a popular-science event held in September 2015. Our goal is both to provide a roadmap for a possible replication and to discuss how the discipline can be used in new fields (science popularization, popular education, public communication)

Immunity Traits in Pigs: Substantial Genetic Variation and Limited Covariation

BACKGROUND: Increasing robustness via improvement of resistance to pathogens is a major selection objective in livestock breeding. As resistance traits are difficult or impossible to measure directly, potential indirect criteria are measures of immune traits (ITs). Our underlying hypothesis is that levels of ITs with no focus on specific pathogens define an individual's immunocompetence and thus predict response to pathogens in general. Since variation in ITs depends on genetic, environmental and probably epigenetic factors, our aim was to estimate the relative importance of genetics. In this report, we present a large genetic survey of innate and adaptive ITs in pig families bred in the same environment. METHODOLOGY/PRINCIPAL FINDINGS: Fifty four ITs were studied on 443 Large White pigs vaccinated against Mycoplasma hyopneumoniae and analyzed by combining a principal component analysis (PCA) and genetic parameter estimation. ITs include specific and non specific antibodies, seric inflammatory proteins, cell subsets by hemogram and flow cytometry, ex vivo production of cytokines (IFNα, TNFα, IL6, IL8, IL12, IFNγ, IL2, IL4, IL10), phagocytosis and lymphocyte proliferation. While six ITs had heritabilities that were weak or not significantly different from zero, 18 and 30 ITs had moderate (0.1<h2≤0.4) or high (h2>0.4) heritability values, respectively. Phenotypic and genetic correlations between ITs were weak except for a few traits that mostly include cell subsets. PCA revealed no cluster of innate or adaptive ITs. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that variation in many innate and adaptive ITs is genetically controlled in swine, as already reported for a smaller number of traits by other laboratories. A limited redundancy of the traits was also observed confirming the high degree of complementarity between innate and adaptive ITs. Our data provide a genetic framework for choosing ITs to be included as selection criteria in multitrait selection programmes that aim to improve both production and health traits