Molecular typing of ‘Candidatus Phytoplasma mali’ and epidemic history tracing by a combined T-RFLP/VNTR analysis approach

Abstract

Apple proliferation caused by '

The insect vector Cacopsylla picta vertically transmits the bacterium ‘Candidatus Phytoplasma mali’ to its progeny

“…Interestingly, a correlation between certain ‘ Ca . Phytoplasma mali’ strains and C. picta or C. melanoneura has been observed (Baric et al ., ), but no biological explanation for this correlation has been described so far. Strain differences might be responsible for a differential spread in insects and subsequent transovarial transmission, e.g.…”

“…In South Tyrol, the first dramatic outbreak of AP coincided with the appearance of C. picta , which was previously absent in the region (Waldner, ; Baric et al ., ). Different studies conducted in Trentino and South Tyrol show that C. picta is more efficient than C. melanoneura in transmitting the disease and that C. picta populations, on average, contain a much higher percentage of infected individuals than C. melanoneura (Frisinghelli et al ., ; Jarausch et al ., , ; Mattedi et al ., ; Baric et al ., ; Mittelberger et al ., ).…”

Spatial and temporal stolbur population structure in a cv. Chardonnay vineyard according to vmp1 gene characterization

“…The hypervariability of the vmp1 gene means that it has been considered as a suitable marker for molecular epidemiology, which is acquiring more and more importance for microbial identification and epidemiological studies (Li et al, 2009). This approach is particularly relevant to uncultivable organisms, and it allows the wide implementation of tracking pathogen movements, identifying source populations, tracing epidemic history, and understanding dispersal routes of pathogens (Baric et al, 2011). Using vmp1 molecular typing, this study *E-mail: g.romanazzi@univpm.it…”

Gene expression and biochemical changes of carbohydrate metabolism in in vitro micro-propagated apple plantlets infected by ‘Candidatus Phytoplasma mali’

“…'Golden Delicious') was performed as reported by Guerriero et al [10]. Infection with subtype AT-2/rpX-A of the in vitro plantlets was proven by the application of the procedure described by Baric et al [15]. Samples for 3 biological replicates, each corresponding to 10 pooled plantlets, were obtained from 30 homogenous in vitro apple plantlets after 30 days of growing.…”

“…To this end, the expression profiles were monitored in in vitro micro-propagated apple plantlets infected with 'Candidatus Phytoplasma mali' ('Ca. P. mali'), the disease agent of apple proliferation (AP) that can have serious impact on the yield of many apple cultivars [15,16]. Unravelling the transcriptional changes associated with carbohydrate metabolism will undoubtedly be an important step towards a better understanding of the molecular mechanisms involved in phytoplasmaehost plant interaction and, in turn, may help to develop future strategies for the control of disease progression in apple.…”