nicotianae in regions that are at risk of contracting tobacco black shank disease and that the Ypt1 gene is a novel and effective target of P. nicotianae LAMP visual detection. “
“Degenerate Potyviridae primers were used to amplify and sequence the 3′-terminal regions of viruses from traditional and modern cultivars of sugarcane with mosaic disease growing in different areas of Yunnan province, China. Seven samples contained Sugarcane mosaic virus (SCMV), 11 contained Sorghum mosaic virus (SrMV) and two contained both viruses. SCMV was
only isolated from traditional cultivars. In a phylogenetic analysis of the partial NIb and complete coat protein coding regions, most SCMV isolates formed a distinctive phylogenetic cluster (named SO) that otherwise contained only three Vietnamese isolates. SCMV variation seems mostly related PLX4032 to host genotype. selleck chemical In the same analysis, the SrMV isolates formed three major groups, one of which is reported for the first time, but the significance of the grouping is unclear. “
“A field survey was conducted to determine the relationship between Ralstonia solanacearum diversity and severity of bacterial wilt
disease in tomato plants grown in plastic greenhouses. Both vegetative and reproductive stages of the plants were surveyed, and the symptoms were empirically categorized into five scales: 0 (asymptomatic): 1st, 2nd, 3rd and 4th. The bacterial wilt pathogen was isolated from infected plants at each disease scale; pathogenic characteristics and population densities of the Metalloexopeptidase bacterial strains were assessed. Two hundred and eighty-two isolates were identified as R. solanacearum, which were divided into three pathogenic types, virulent, avirulent and interim, using the attenuation index (AI) method and a plant inoculation bioassay. Ralstonia solanacearum was detected in all asymptomatic and symptomatic
tomato plants, with population numbers, ranging from 10.5 to 86.7 × 105 cfu/g. However, asymptomatic plants harboured only avirulent or interim R. solanacearum, whereas tomato plants displaying 1st or 2nd disease degree contained interim and virulent strains. Additionally, 3rd and 4th degree plants harboured only virulent strains. The disease was more severe in vegetative-stage plants (disease severity index (DSI) 0.20) with higher total numbers of interim and virulent R. solanacearum strains than those in reproductive-stage plants (DSI 0.12). Three pathotypes of R. solanacearum coexisted in a competitive growth system in the tomato field, and their distribution closely correlated with the severity of tomato bacterial wilt. “
“Evaluation of 130 accessions of rapeseed-mustard germplasm grown at the National Bureau of Plant Genetic Resources, New Delhi, India during the winter season (2011–2012) revealed the occurrence of a leaf curl disease in seven accessions. The occurrence of the disease was observed in another 62 of 525 accessions evaluated during 2012–2013.