A novel East African monopartite begomovirus-betasatellite complex that infects Vernonia amygdalina

The complete genomes of a monopartite begomovirus (genus Begomovirus, family Geminiviridae) and an associated betasatellite found infecting Vernonia amygdalina Delile (family Compositae) in Uganda were cloned and sequenced. Begomoviruses isolated from two samples showed the highest nucleotide sequence identity (73.1% and 73.2%) to an isolate of the monopartite begomovirus tomato leaf curl Vietnam virus, and betasatellites from the same samples exhibited the highest nucleotide sequence identity (67.1% and 68.2%) to vernonia yellow vein Fujian betasatellite. Following the current taxonomic criteria for begomovirus species demarcation, the isolates sequenced here represent a novel begomovirus species. Based on symptoms observed in the field, we propose the name vernonia crinkle virus (VeCrV) for this novel begomovirus and vernonia crinkle betasatellite (VeCrB) for the associated betasatellite. This is the first report of a monopartite begomovirus-betasatellite complex from Uganda

Desmodium mottle virus, the first legumovirus (genus Begomovirus) from East Africa

A novel bipartite legumovirus (genus Begomovirus, family Geminiviridae), that naturally infects the wild leguminous plant Desmodium sp. in Uganda, was molecularly characterized and named Desmodium mottle virus. The highest nucleotide identities for DNA-A, obtained from two field-collected samples, were 79.9% and 80.1% with the legumovirus, soybean mild mottle virus. DNA-B had the highest nucleotide identities (65.4% and 66.4%) with a typical non-legumovirus Old World begomovirus, African cassava mosaic virus. This is the first report of a legumovirus in East Africa and extends the known diversity of begomoviruses found infecting wild plants in this continent

Oleic acid variation and marker-assisted detection of Pervenets mutation in high- and low-oleic sunflower cross

High-oleic sunflower oil is in high demand on the market due to its heart-healthy properties and richness in monounsaturated fatty acids that makes it more stable in processing than standard sunflower oil. Consequently, one of sunflower breeder's tasks is to develop stable high-oleic sunflower genotypes that will produce high quality oil. We analyzed variability and inheritance of oleic acid content (OAC) in sunflower, developed at the Institute of Field and Vegetable Crops, by analyzing F-1 and F-2 progeny obtained by crossing a standard linoleic and high-oleic inbred line. F-2 individuals were classified in two groups: low-oleic with OAC of 15.24-31.28% and high-oleic with OAC of 62.49-93.82%. Monogenic dominant inheritance was observed. Additionally, several molecular markers were tested for the use in marker-assisted selection in order to shorten the period of detecting high-oleic genotypes. Marker F4-R1 was proven to be the most efficient in detection of genotypes with Pervenets (high-oleic acid) mutation

Analysis of genetic diversity among Macrophomina phaseolina (Tassi) Goid. isolates from Euro-Asian countries

The study assessed the genetic variability among Macrophomina phaseolina (Tassi) Goid. isolates originating from six different countries (Turkey, Bulgaria, Romania, Spain, Ukraine and Serbia), collected mostly from sunflower, but also maize, soybean, flax, common bean and zebra plant. RAPD analysis was based on 154 polymorphic bands obtained with 14 OPA primers. RAPD markers OPA-02-OPA-05, OPA-07-OPA-13 and OPA-18-OPA-20 were found to be suitable for measuring the genetic relatedness and detecting variability in M. phaseolina populations. Cluster analysis revealed high genetic diversity of M. phaseolina isolates within the same country of origin, but clear differentiation according to the isolates' host plant and geographical origin was not observed. Contingency analysis and corrected contingency coefficients enabled determination of RAPD markers associated with geographical origin of isolates, as well as markers specific for non-sunflower isolates. Marker OPA 10_1750 was found to be highly specific for the isolates from Turkey, while two markers, OPA 3_1250 and OPA 9_800, could be used for differentiation of isolates originating from sunflower from isolates originating from other host plants