No abstract

No abstract

No abstract

Mountain pine (Pinus mugo Turra), is a coniferous native to the highlands of central Europe. Our previous study has revealed that mountain pine proliferation decline (MPPD) disease in the Curonian Spit of Lithuania is caused by a 'Candidatus Phytoplasma pini'-related strain (16SrXXI-A). However, the insect vector of MPPD has not been identified. In this study, we conducted a survey to determine potential insect vectors of MPPD phytoplasma for three consecutive years (2016-2019). More than 1,000 insect samples were collected in four locations of the Curonian Spit. These insects were identified as belonging to six families and ten genera. The presence of phytoplasma in insect samples was examined by nested PCR using phytoplasma-specific primers (P1A/16S-SR and R16F2n/R16R2n). Phytoplasmas were detected in Cinara (Cinara) pini (Scots pine aphid), Cinara (Cinara) piniphila and Cinara (Schizolachnus) pineti (waxy grey pine needle aphid) insect samples. Subsequent RFLP analysis showed that the PCR-RFLP profile of these positive insect samples was consistent with that of the MPPD of diseased pine trees. These results suggest that C. (C.) pini, C. (C.) piniphila and C. (S.) pineti may be potential insect vectors of MPPD phytoplasma. The findings from this survey will provide useful information for the management of MPPD disease.

Information about Eulachnini species in Lithuania concerns fragmentary faunistic data, therefore, their diversity, abundancy and ecological specificity is insufficiently studied. The aim of this work was to present available information on the new to Lithuania Eulachnini aphid species detected on coniferous plants in Lithuania in 2004 - 2017, with special regard to their potential impacts on forestry. Partial COI sequences (652 bp) were used to confirm morphology-based identification of new to Lithuania Eulachnini species and to investigate their genetic diversity and relationships with samples collected in other countries. Twenty-seven aphid species of the tribe Eulachnini were detected in 2004 – 2017 in Lithuania. Eight of them are reported from Lithuania for the first time: Cinara (Cinara) brauni, C. (C.) kochiana, C. (C.) neubergi, C. (C.) laricis, C. (C.) pectinatae, C. (C.) piceae, Eulachnus brevipilosus and E. nigricola. Five species of Eulachnini (C. (C.) piceae, C. (C.) nuda, C. (C.) piceicola, C. (C.) pinea, and C. (C.) pini) appeared to be most promising honey dew producers because their host plants, Picea abies and Pinus sylvestris, are the most common conifers in Lithuania. Although five species of Eulachnini were listed in the identification key of forest pests in Lithuania, none of them were of particular importance for now. Out of the recently reported species, only Cinara piceae may be a potential forest pest as it appeared to be rather common in Lithuania and it has been reported as a pest of firs in nurseries of Czech Republic and Northern Caucasus. Most of the samples from Lithuania represented COI haplotypes, which were not previously detected in other countries.