Tatjana Perović

Diversity and localization of bacterial symbionts in three whitefly species (Hemiptera: Aleyrodidae) from the east coast of the Adriatic Sea

Several whitefly species (Hemiptera: Aleyrodidae) are cosmopolitan phloem-feeders that cause serious damage in numerous agricultural crops. All whitefly species harbor a primary bacterial symbiont and a diverse array of secondary symbionts which may influence several aspects of the insects biology. We surveyed infections by secondary symbionts in Bemisia tabaci (Gennadius), Trialeurodes vaporariorum (Westwood) and Siphoninus phillyreae (Haliday) from areas in the east cost of the Adriatic Sea. Both the Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) B. tabaci genetic groups were detected in Montenegro, whereas only the MED was confirmed in Croatia. Trialeurodes vaporariorum and S. phillyreae were found in all areas surveyed. MEAM1 and MED exhibited similarity to previously reported infections, while populations of T. vaporariorum from Montenegro harbored Rickettsia, Wolbachia and Cardinium in addition to previously reported Hamiltonella and Arsenopnohus. Siphoninus phillyreae harbored Hamiltonella, Wolbachia, Cardinium and Arsenophonus, with the latter appearing in two alleles. Multiple infections of all symbionts were common in the three insect species tested, with some reaching near fixation. Florescent in situ hybridization showed new localization patterns for Hamiltonella in S. phillyreae, and the morphology of the bacteriosome differed from that observed in other whitefly species. Our results show new infections with bacterial symbionts in the whitefly species studied. Infections with the same symbionts in reproductively isolated whitefly species confirm complex relationships between whiteflies and bacterial symbionts, and suggest possible horizontal transfer of some of these bacteria.

Population dynamics of pre-imaginal stages of olive fruit fly Bactrocera oleae Gmel. (Diptera, Tephritidae) in the region of bar (Montenegro).

Olive fruit fly is the most harmful pest of olive fruits and important for oil production. Damage involves yield reduction as a consequence of premature fruit drop, but also a reduced quality of olive oil and olive products. There is little available data regarding the biology of Bactrocera oleae in Montenegro. Knowledge of the pest life cycle and development would improve optimization of insecticide application timing and protection of fruits, and reduce adverse effects on the environment. Investigation was conducted on the Žutica variety in an olive grove located in Bar during a three-year period. Population dynamics of the pre-imaginal stages and level of fruit infestation were monitored from mid-July until the end of October. The results of this three-year investigation showed that the beginning of infestation was always at the end of July. It was also found that, depending on environmental conditions, the level of infestation was low until the end of August. In September and October it multiplied, and reached maximum by the end of October. Regarding infestation structure, eggs and first instar larvae were the dominant developmental stages of the pest until the middle of September. From mid-September until mid-October all developmental stages (eggs, larvae, pupae) were equally present in infested fruits. Pupae, cocoons and abandoned galleries prevailed until the harvest.

FIRST REPORT OF FIG MOSAIC VIRUS, FIG LEAF MOTTLE- ASSOCIATED VIRUS 1 AND FIG MILD MOTTLE-ASSOCIATED VIRUS INFECTING FIG (Ficus carica) IN MONTENEGRO

In Montenegro more than 200 000 fig trees are registered with an annual production of about 4000 t. A survey was conducted on fig trees of different varieties, located in a commercial orchard in Podgorica and a germplasm collection located in Bar, Montenegro, to assess the presence of five fig viruses i.e. Fig mosaic virus (FMV), Fig leaf mottle-associated virus 1 and 2 (FLMaV-1 and -2), Fig latent virus 1 (FLV-1) and Fig mild mottle-associated virus (FMMaV). In May 2015, leaf samples were taken from 21 fig trees showing leaf discolorations, vein clearing, ring spots, leaf distortion and mosaic symptoms. Total RNA was extracted using RNeasy Plant Mini Kit (QIAGEN) and tested by RT-PCR using virus-specific primers (Elbeaino et al., 2006, 2009, 2010). RT-PCR results showed infections with FMV (9 of 21 samples tested), FLMaV-1 (18 of 21) and FMMaV (2 of 21), whereas FLMaV-2 and FLV-1 were not detected. FMMaV was identified only in samples from Bar in mixed infection with FMV and FLMaV-1. Nucleotides sequence analyses of PCR amplicons obtained (GenBank accession Nos. KU198374-KU198377, KU198383-KU198389) revealed that at the nucleotide level, FMV, FLMaV-1 and FMMaV isolates from Montenegro shared 86-95%, 93-95% and 84- 95% identity, respectively with homologues in the GenBank. To our knowledge, this is the first report of FMV, FLMaV-1 and FMMaV in fig trees in Montenegro. In the future, an extensive survey on more samples could allow a better evaluation of the sanitary status of this crop in the country.