Light-dependent segregation of begomoviruses in Asystasia gangetica leaves.

Asystasia gangetica (Acanthaceae) from tropical Africa and Asia is used as source of food and for medical applications. Plants collected in West Africa in the 1980s with typical geminivirus symptoms showed an unusual symptom segregation that included vein yellowing, curling and mosaic, which were present simultaneously or separately on different leaves of the same plant or on different plants propagated as cuttings from a single plant. Rolling-circle amplification in combination with restriction fragment length polymorphism analysis followed by deep sequencing of the RCA products identified two geminiviruses in these plants.

Evolutionary liberties of the Abutilon mosaic virus cluster.

Two new strains of Abutilon mosaic virus (AbMV; Geminiviridae) from Germany (Stuttgart) and France (Paris) have been characterized by circomics, direct pyrosequencing of rolling circle amplification (RCA) products, as well as conventional cloning and Sanger sequencing. RCA combined with an analysis of restriction fragment length polymorphisms confirmed the completeness of the sequence determination and a close relationship of both isolates for DNA A with 99 % nucleotide sequence identity. Phylogenetic tree reconstruction supported their clustering with other AbMV strains in a clade with Middle American begomoviruses, whereas South American begomoviruses that infect Abutilon or Sida micrantha are less closely related.

Circomics of Cuban geminiviruses reveals the first alpha-satellite DNA in the Caribbean.

Circomics (circular DNA genomics), the combination of rolling circle amplification (RCA), restriction fragment length polymorphism (RFLP) analysis and pyro-sequencing, has been used recently to identify geminiviruses with high efficiency and low costs. Circular DNAs associated with Cuban geminiviruses were characterised by RCA/RFLP analysis and 454 sequencing of two batches of DNA amplified from selected plant samples as well as individual cloning and Sanger sequencing of DNA components and compared to other geminiviral DNAs by phylogenetic analysis. Cuban geminiviruses that were closely related to each other challenged the circomics approach.

Leaf microbiota of strawberries as affected by biological control agents.

The increasing use of biological control agents (BCAs) against Botrytis cinerea in strawberry raises the question of whether there are any undesirable impacts of foliar applications of BCAs on nontarget microorganisms in the phyllosphere. Therefore, our objective was to investigate this issue within a field study. Strawberry plants were repeatedly sprayed with three BCAs-namely, RhizoVital 42 fl.

Effects on diversity of soil fungal community and fate of an artificially applied Beauveria bassiana strain assessed through 454 pyrosequencing.

The entomopathogenic fungus Beauveria bassiana is widely used as a biological control agent (BCA) for insect pest control, with fungal propagules being either incorporated into the potting media or soil or sprayed directly onto the foliage or soil. To gain a better understanding of entomopathogenic fungal ecology when applied as a BCA to the soil environment, a case study using tag-encoded 454 pyrosequencing of fungal ITS sequences was performed to assess the fate and potential effect of an artificially applied B. bassiana strain on the diversity of soil fungal communities in an agricultural field in India.

Circular DNA genomics (circomics) exemplified for geminiviruses in bean crops and weeds of northeastern Brazil.

Circomics was coined to describe the combination of rolling circle amplification (RCA), restriction fragment length polymorphism (RFLP) and pyro-sequencing to investigate the genome structures of small circular DNAs. A batch procedure is described using 61 plant samples from Asia, South America and Central America which revealed 83 contig sequences of geminiviral DNA components and 4 contig sequences of DNA satellites. The usefulness of this approach is validated for the Brazilian begomoviruses, and the sequence fidelity is determined by comparing the results with those of conventional cloning and sequencing of Bolivian begomoviruses reported recently.

Assessment of bacterial endosymbiont diversity in Otiorhynchus spp. (Coleoptera: Curculionidae) larvae using a multitag 454 pyrosequencing approach.

Background: Weevils of the genus Otiorhynchus are regarded as devastating pests in a wide variety of horticultural crops worldwide. So far, little is known on the presence of endosymbionts in Otiorhynchus spp..