Phytoplasmas were detected in one sample from symptomatic plants by nested PCR assay employing 16S rRNA gene primers P1/P7 followed by R16F2n/R16R2. Virtual RFLP analysis of the resulting products (F2nR2 region) shown that total of two different groups (16SrI and 16SrV) phytoplasmas associated with the infected jujube. This is the first report of phytoplasmas mixed infection selleckchem of jujube in China. “
“Leaf samples were collected from four spider lily and tobacco plants with tospovirus-like symptoms in Yunnan province. The nucleocapsid ORFs of the four isolates were obtained by RT-PCR, cloning and sequencing
of the amplified products. Nucleotide sequences of the obtained amplicons were more than 90% identical to that of Calla lily chlorotic spot virus (CCSV) isolates deposited in the GenBank database. The virus induced systematic leaf necrosis, chlorotic lesions, rugosity DAPT mouse and deformation on mechanically inoculated experimental hosts. This is the first report of CCSV in mainland China, and also on spider lily and tobacco. “
“Maize chlorotic mottle virus (MCMV) is one of the co-infection pathogens that cause corn (maize) lethal necrosis, but the transmission mechanism of MCMV is not yet clear. In order
to determine the ability of western flower thrips (Frankliniella occidentalis; WFT) to transmit MCMV, imported maize seeds from Thailand were germinated in an insect-free greenhouse and the seedlings were tested for the transmission by WFT of chlorotic mottle virus disease. The thrips (WFT), starved for 48 h then allowed to feed for 30 min on maize plants infected with MCMV or asymptomatic maize plants, were transferred to healthy seedlings. After 35 days, the seedlings with WFT from diseased maize plants showed chlorotic mottle symptoms, whereas seedlings with WFT from asymptomatic maize plants
remained healthy. A single band of 711 bp was amplified by RT-PCR medchemexpress using primers MCMV-F/MCMV-R from the MCMV-infected plants and WFT collected from the diseased plants. Sequencing of the amplified product and further sequence comparison indicated that the two viruses from both sources showed 99% similarity of nucleotides and they should be regarded as identical. In addition, isometric particles c. 30 nm in diameter, characteristic of MCMV, were found in the WFT samples from diseased maize plants. Thus, it is concluded that WFT transmits MCMV. Our findings suggest that corn lethal necrosis disease can be controlled or minimized by the eradication of WFT from the field or greenhouses. “
“Wheat stripe rust, caused by the fungal pathogen Puccinia striiformis f.sp. tritici (PST), is a major disease of wheat in temperate-cold climates. The identification of new markers would ease the procedure for evaluating the ongoing pathogen evolution.