The influence of the developmental stage of microspores on establishing isolated microspore cultures of three Hungarian ('Szegedi 80', 'Szegedi 178', and 'Remény') and three Spanish ('Jeromin', 'Jariza', and 'Jaranda') pepper genotypes was investigated. Donor anthers containing 80% uninucleated and 20% binucleated microspores yielded the highest frequency of successful microspore cultures. Cocultures with wheat, line 'CY-45', ovaries exhibited enhanced frequency of embryoid production than those with pepper ovaries. Differences in efficiency of isolated pepper microspore culture establishment were observed among different pepper genotypes. Green plantlets were regenerated from microspore-derived embryoids, but some were exhibited abnormal growth habits, such as leaf rosetting. A total of seven fertile microspore-derived plants were obtained, including three 'Jariza', three 'Jaranda', and a single 'Szegedi 80' plant.

Background: Dark septate endophytes (DSEs) represent a form-group of ascomycetous fungi that inhabit the roots of a wide range of plant species, but our knowledge on their interaction with the host plants is still limited. Aims: This study was conducted to examine the effect of DSEs on the nutrition and growth of tomato (Solanum lycopersicum) in order to assess their potential application in horticultural plant production. Methods: The capacity of two model DSE species, Periconia macrospinosa and Cadophora sp. to mobilise different forms of N and P (organic and inorganic) was analysed, and an in vitro bio assay with tomato plantlets was applied to screen the compatibility of these fungi with the plant. Pot-culture experiments with and without compartments were conducted to study the effects of these DSEs on the growth and nutrient uptake of tomato plants grown with organic and inorganic N and P sources. Results: Periconia macrospinosa, but not Cadophora sp., increased the root and shoot biomass of tomato plants when organic nutrient resources were present, and both DSEs promoted shoot growth when cultivated with inorganic fertilisers. Analysis of N and P concentrations indicated that the growth response of tomato with inorganic fertilisation was not based on DSE-improved plant nutrition. However, P. macrospinosa improved N uptake from organic sources. Conclusion: The positive effects of DSEs seem to be due to nutrient mobilisation rather than to hyphal transport to the plant.

The 2b protein of Cucumber mosaic virus has a role in nearly all steps of the viral cycle including cell-to-cell movement, symptom induction and suppression of antiviral RNA silencing. Previous studies demonstrated the presence of 2b protein in the nucleus and in cytoplasm as well. Phosphorylation site of 2b protein is conserved in all CMV isolates, including proposed constitute motifs for casein kinase II and cyclin-dependent kinase 2. To discern the impact of 2b protein phosphorylation, we created eight different mutants to mimic the non-phosporylated (serine to alanine) as well as the phosphorylated state (serine to aspartic acid) of the protein. We compared these mutants to the wild-type (Rs-CMV) virus in terms of symptom induction, gene silencing suppressor activity as well as in cellular localization. Here, in this study we confirmed the phosphorylation of 2b protein in vivo, both in infected N. benthamiana and in infiltrated patches. Mutants containing aspartic acid in the phosphorylation site accumulated only in the cytoplasm indicating that phosphorylated 2b protein could not enter the nucleus. We identified a conserved dual phosphorylation switch in CMV 2b protein, which equilibrates the shuttling of the 2b protein between the nucleus and the cytoplasm, and regulates the suppressor activity of the 2b protein.