indigoferae seems to be more virulent than P. irregulare. “
“Potyviruses are a common threat for snap bean production in Bulgaria. During virus surveys of bean plots in the south central region, we identified an isolate of Clover yellow vein virus (ClYVV), designated ClYVV 11B, by indirect ELISA and RT-PCR causing severe mosaic symptoms and systemic necrosis. Indirect
and direct ELISA using ClYVV antisera differentiated the ClYVV isolate from Bean yellow mosaic virus (BYMV), but serological analysis could not distinguish the Bulgarian isolate ClYVV 11B from an Italian ClYVV isolate used as a reference (ClYVV 505/7). RT-PCR analyses with specific primers revealed that both isolates were ClYVV. Sequence analysis of an 800 bp fragment corresponding to the coat protein coding region showed 94% identity at the nucleotide level between the two isolates. Phylogenetic analyses of aligned c-Met inhibitor nucleotide sequences available in the database confirmed the existence of two groups of isolates, but ClYVV 11B and ClYVV505/7 belonged to the same group. We compared the virulence of both isolates on a set of differential cultivars and 19 bean breeding lines resistant to Bean common mosaic virus (BCMV) and Bean common mosaic necrosis virus (BCMNV): Bulgarian isolate ClYVV 11B was able to infect systemically
all tested bean check details differential cultivars and breeding lines including those with genotypes Ibc3 and Ibc22; Italian isolate ClYVV 505/7 was not able to infect systemically some differentials with genotypes bc-ubc1, bc-ubc22, bc-ubc2bc3, Ibc12, Ibc22, Ibc3. The role of bc3 gene as a source of resistance to potyviruses is discussed. “
“Moisture variables MCE公司 have not been a consistent predictor of Rhizoctonia web blight development on container-grown azalea. A vapour pressure deficit <2.5 hPa was the only moisture variable attributed to slow web blight development in one study, yet in another study, frequent rainfall provided a moderately
successful decision criterion for applying fungicide. To characterize web blight development in response to leaf wetness, plants were inoculated with two isolates of binucleate Rhizoctonia AG-U and maintained in a glasshouse in open-topped, clear plastic chambers with 0-, 4-, 8-, 12-, 16- and 20-h daily cycles of 20–30 s mist at 30-min intervals under day and night temperatures of 29 and 22°C, respectively. Leaf wetness duration closely matched misting cycle duration. Disease incidence was measured per chamber as a mean of the number of blighted leaves per total leaves per stem. A mixed model procedure was used to compare area under the disease progress curves (AUDPC) over 4–6 weeks in experiments performed in 2008 to 2010. Isolate response to mist cycle durations was not different (P = 0.4283) in 2008, but was different in 2009 (P = 0.0010) and 2010 (P < 0.0001) due to one isolate becoming less aggressive over time.