In vitro cultivation and biocontrol potential of Botryosphaeria visci against European mistletoe (Viscum album L.)

To improve the biological control of white mistletoe (European mistletoe) additional detailed information on Botryosphaeria visci infection, its basic nutritional requirements, growth, and in vitro growth characteristics is needed. The objectives of this study were to isolate and identify the fungus B. visci associated with Viscum аlbum from Sorbus aucuparia, to provide information on its in vitro introduction and growth characteristics on different media, and to test the pathogenicity of the isolated fungus. To achieve these goals, the morphology of conidiophores from infected parts of mistletoe was evaluated by microscopy. The isolate from fresh collections of V. album was identified as Sphaeropsis visci anamorph of ascomycete Botryosphaeria visci. The morphology of the vegetative mycelium and growth of B. visci varied depending on the media used. The best medium supporting growth and sporulation was oat- meal. Re-infection of European mistletoe in laboratory conditions showed positive results on liquid media, and in field conditions but only after mechanical damage to the mistletoe leaves. Our results expand the knowledge regarding the optimal cultivation of this fungus. This may facilitate further mycological and pathological studies involving B. visci isolates, and the results have a theoretical basis for the implementation of measures for the prevention and control of mistletoe

Genome-wide identification and evolution of the tubulin gene family in Camelina sativa

Abstract Background Tubulins play crucial roles in numerous fundamental processes of plant development. In flowering plants, tubulins are grouped into α-, β- and γ-subfamilies, while α- and β-tubulins possess a large isotype diversity and gene number variations among different species. This circumstance leads to insufficient recognition of orthologous isotypes and significantly complicates extrapolation of obtained experimental results, and brings difficulties for the identification of particular tubulin isotype function. The aim of this research is to identify and characterize tubulins of an emerging biofuel crop Camelina sativa. Results We report comprehensive identification and characterization of tubulin gene family in C. sativa, including analyses of exon-intron organization, duplicated genes comparison, proper isotype designation, phylogenetic analysis, and expression patterns in different tissues. 17 α-, 34 β- and 6 γ-tubulin genes were identified and assigned to a particular isotype. Recognition of orthologous tubulin isotypes was cross-referred, involving data of phylogeny, synteny analyses and genes allocation on reconstructed genomic blocks of Ancestral Crucifer Karyotype. An investigation of expression patterns of tubulin homeologs revealed the predominant role of N6 (A) and N7 (B) subgenomes in tubulin expression at various developmental stages, contrarily to general the dominance of transcripts of H7 (C) subgenome. Conclusions For the first time a complete set of tubulin gene family members was identified and characterized for allohexaploid C. sativa species. The study demonstrates the comprehensive approach of precise inferring gene orthology. The applied technique allowed not only identifying C. sativa tubulin orthologs in model Arabidopsis species and tracking tubulin gene evolution, but also uncovered that A. thaliana is missing orthologs for several particular isotypes of α- and β-tubulins