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[EN] Plum pox virus(PPV) is the causal agent of sharka, the most devastating virus disease ofPrunusspecies. PPV is transmitted by vegetative propagation, particularly by grafting, as well as by aphid species in a nonpersistent manner. The objective of this paper was to evaluate the prevalence and diversity of PPV-vector aphid species in representative European areas of prunus cultivation. Four experimental nursery plots were established in Skierniewice (Poland), Liria (Spain), Plovdiv (Bulgaria) and Bistrita (Romania). Aphid population was weekly monitored using the sticky shoot method in spring and/or autumn in each nursery plot. Furthermore, we estimated the relative efficiency factor for the main PPV-vector aphid species using bibliographic and reference data. Aphid diversity in each nursery plot was assessed using the Shannon index and the number of estimated aphid species was calculated by the rarefaction method. The highest diversity of aphid species population was reported in Plovdiv in spring while the lowest diversity was found in Liria in spring. A cluster analysis based on Morisita-Horn similarity index was performed to study the differences in species composition between the four nursery plots and seasons. Aphid population was clearly grouped by location and season. Results showedAphis spiraecolaandHyalopterus prunicomplex were typically spring aphid species, whileAnoecia corniandRhopalosiphum padidominated autumn catch. Regarding PPV-vector aphid species present in nursery plots,A. spiraecolawas the most prevalent PPV-vector aphid species in Liria and in Bistrita, showing a high relative efficiency factor of PPV transmission (0.91). Consequently,A. spiraecolashould be considered a key actor in the spread of PPV in these regions.Hyalopterus prunicomplex was the most prevalent PPV-vector aphid species in Skierniewice and Plovdiv, showing a very low relative efficiency factor of PPV transmission (0.09). Therefore, the role ofH. prunicomplex in spread of PPV in these regions can be considered negligible. Furthermore, we statistically demonstrated that the presence of specific PPV-vector aphid species is associated with the spread of the disease, whereas the biodiversity of aphid species population does not affect the spread of PPV. Finally, the advantages of the use of vector pressure index in the management of sharka disease are discussed., The research leading to these results were funded by the EU Seventh Framework Programme (FP7/2007-2013), SharCo project grant no. 204429 and by grants from the Spanish Ministry of Science and Education (MEC, AGL2009-07531 and INIA RTA2005-00190). Authors thank I. Baias, S. Sabin (SCDP, Bistrita), B. Tamargo and J. Micó (Cooperativa Vinícola, Líria) for technical assistance in the experimental plots, Viveros Orero and Agromillora Iberia for providing the certified rootstock plants. E. Vidal was recipient of a grant from the Spanish Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA).

The fauna of aphids appearing on cucurbits, including oilseed pumpkin have been poorly investigated in Serbia. Yellow water traps were used to determine the diversity of aphid species visiting cucurbits in Serbia and to monitor their flight activity. During the years 2009 to 2011, a total of 1,447 specimens were collected and a total of 57 different aphid taxa were identified. In 2009, the highest total number of aphids were caught (755), followed by 203 and 489 aphids in 2010 and 2011, respectively. The most abundant species were Aphis fabae (15%), Myizus persicae (13.4%) and Acyrthosiphonpisum (11.7%), followed by Anoecia corni (6.4%) and Aphis gossypii (5.6%). All of them, except A. corni, are reported as efficient vectors of cucurbit viruses. These five species represent 52.1% of all aphid species collected within this study. Out of 57 taxa found in oilseed pumpkin crops, 17 are known as vectors of ZYMV, 18 of WMV and 15 of CMV. Generally, 25 out of a total of 57 taxa are known as vectors of at least one of three viruses present in Serbia. From total of 1,447 specimens collected during three years of investigation, 917 (63.4%) are vectors of at least one of three viruses. Individual oilseed pumpkin plants were frequently colonized by A. gossypii during all three years of investigation. Results of this study showed that Serbian oilseed pumpkin growing localities are grouped among medium to reach in aphidofauna, according to total Shannon-Weaver index values which varied from 1.8 to 2.8. The highest value of Shannon-Weaver (2.8) was recorded in the Bački Petrovac I locality in 2009, while the lowest Shannon-Weaver (1.8) was recorded in Kisač locality in 2010. The maximum values of Shannon-Weaver diversity index in almost all crops were recorded in the second week of investigation or in early stages of oilseed pumpkin growth when plants had 5-6 true leaves or were in flowering stage, when potential virus infection could lead to significant yield losses. Afidofauna koja se javlja na tikvama, uključujući uljanu tikvu do sada nije dobro ispitana u Srbiji. Da bi utvrdili diverzitet lisnih vaši koje posećuju useve tikava u Srbiji, kao i da bi pratili aktivnost i dinamiku njihovog leta, koristili smo žute lovne klopke. Tokom perioda od 2009. do 2011. godine ukupno je sakupljeno 1447 jedinki i determinisano 57 taksona lisnih vaši. Tokom 2009. godine, uhvaćen je najveći broj jedinki (755), dok je tokom 2010. i 2011. godine uhvaćeno 203, odnosno 489 jedinki lisnih vaši. Najzastupljenije vrste bile su Aphis fabae (15%), Myzus persicae (13,4%) i Acyrthosiphon pisum (11,7%), a zatim Anoecia corni (6,4%) i Aphis gossypii (5,6%). Za sve vrste, osim za A. corni, potvrđeno je da su vektori virusa tikava. Ovih pet najzastupljenijih vrsta predstavljaju 52,1% od svih sakupljenih jedinki vaši u toku ovih istraživanja. Od ukupno 57 taksona nađenih u usevima uljane tikve, 17 su poznati vektori ZYMV, 18 WMV i 15 CMV. Ukupno posmatrano, 25 od 57 nađenih taksona su vektori bar jednog od tri virusa tikava prisutnih u Srbiji. Od ukupno 1447 jedinki sakupljenih tokom tri godine istraživanja, 917 (63,4%) su vektori bar jednog od tri virusa tikava. Kolonizacija pojedinačnih biljaka uljane tikve vrstom A. gossypii uočavana je često tokom sve tri godine istraživanja. Rezultati ovih istraživanja, na osnovu ukupnog Shannon-Weaver-ovog indeksa diverziteta koji je varirao između 1,8 i 2,8, ukazuju da se lokaliteti na kojima se gaji uljana tikva u Srbiji svrstavaju u red srednje bogatih do bogatih po sastavu i brojnosti afidofaune. Najveća vrednost Shannon-Weaver-ovog indeksa diverziteta (2,8) zabeležena je tokom 2009. godine na lokalitetu Bački Petrovac I, dok je najniži indeks diverziteta (1,8) zabeležen na lokalitetu Kisač tokom 2010. godine. Shanon-Weaver-ov indeks diverziteta u gotovo svim ispitivanim usevima dostigao je maksimalne vrednosti u drugoj nedelji istraživanja ili u ranim fazama razvoja uljane tikve kada biljke imaju 5-6 pravih listova ili su u fazi cvetanja, što predstavlja najosetljivije faze za ostvarenje infekcije virusima koje mogu da dovedu do značajnih gubitaka u prinosu.

The structure of the male reproductive system of Anoecia (Anoecia) corni Fabricius, 1775, is discussed. On the basis of histological sections and whole mount preparations, the following elements in the structure of the male reproductive system have been examined: the structure of testis and the stage of spermatogenesis; the connection of testis and vasa deferentia; the position and the histological structure of the wall of vasa deferentia; and the development of accessory glands and the ejaculatory duct as well as the structure of the external genitalia. These characters are discussed with reference to the higher classification of Aphidoidea and the taxonomic position of Anoeciidae.

Summary The studies on aphid flights using Johnson's aspirator in the Silesian Province in southern Poland began in 2007. Regularly captured insect species according to the list of 9 aphid species recommended for observation by the Institute of Plant Protection – National Research Institute (IPP – NRI) in Poznan, allowed comparing aphid incidence over the 5-year period. The greatest abundance of aphids was reported in the spring and autumn. The most numerous species were Rhopalosiphum padi (L.) and Anoecia corni (F.). Aphid flight data were regularly posted on the webpage of the IPP – NRI in Poznan to indicate potential risks for growers.

SUMMARY Live trapping at 0.9 m of alate aphid vectors of barley yellow dwarf virus (BYDV) at Aberystwyth from 1970 to 1979 showed that ten species transmitted the virus to oat test plants. Conversion of percentage infective at 0.9 m to numbers infective based on continuous trapping at 1.2 m showed Rhopalosiphum padi and R. insertum to be the main vector species in most years, whilst Metopolophium dirhodum and Sitobion auenae were normally of minor importance. The data obtained suggest that epiphytotics of BYDV in autumn-sown cereals were caused by numerous infective vectors flying late in the year and transmitting severe strains of the virus. Evidence is presented that gynoparae and males of R. padi are involved in the autumn spread of BYDV and that three further aphid species, Anoecia corni, Metopolophium albidum and M. frisicum are BYDV vectors. The use of live and continuous trapping techniques in forecasting BYDV epiphytotics is discussed.