Utvđivanje nivoa rezistentnosti Myzus persicae (Sulzer) biohemijskim metodama

Peach/potato aphid Myzus persicae (Sulzer) has developed three mechanisms of resistance: overproduction of one or two closely related carboxylesterases (E4 and FE4), production of modified acetylcholinesterase (MACE and knockdown resistance). Biochemical diagnostic methods can be used to identify levels of carboxylesterase production and sensitivity of modified acetylcholinesterase and, based on the values acquired we can classify aphids into one of the resistance cathegories. We used two tests: the total esterase activity test and test for checking sensitivity of acetylcholinesterase (MACE). Myzus periscae persicae from peach and Myzus persicae nicotianae from tobacco were tested. The total esterase activity test showed that 65% of the aphids tested were moderately resistant and 35% were highly resistant. Resistance based on the production of modified acetylcholinesterase is less represented because 80% of the aphids tested were susceptible to pirimicarb, which was used in the experiment. Also, both tests showed that aphids from tobacco were more susceptible than aphids from peach.Kod Myzus persicae (Sulzer) do sada su utvrđena tri tipa rezistentosti: povećana produkcija karboksilesteraza E4 i FE4, stvaranje modifikovane acetilholinesteraze i „knock-down” rezistentnost. Biohemijskim metodama moguće je izmeriti količinu karboksilesteraza, kao i aktivnosti modifikovane acetilholinesteraze i na osnovu dobijenih vrednosti, vaši svrstati u neku od kategorija rezistentnosti. Korišćena su dva testa, test totalne esterazne aktivnosti i test za proveru aktivnosti modifikovane acetilholinesteraze (MACE). Testirane su Myzus persicae persicae sa breskve i Myzus persicae nicotianae sa duvana. Test totalne esterazne aktivnosti pokazao je da 65% testiranih jedinki pripada kategoriji umereno rezistentnih vašiju, dok je 35% veoma rezistentno. Rezistentnost koja se zasniva na stvaranju modifikovane acetilholinesteraze manje je zastupljena, jer je čak 80% testiranih vašiju osetljivo na dejstvo pirimikarba, koji je korišćen u testu. Takođe, oba testa su pokazala da su vaši sa duvana osetljivije na dejstvo insekticida od vašiju sa breskve

Seven recommendations to make your invasive alien species data more useful

Science-based strategies to tackle biological invasions depend on recent, accurate, well-documented, standardized and openly accessible information on alien species. Currently and historically, biodiversity data are scattered in numerous disconnected data silos that lack interoperability. The situation is no different for alien species data, and this obstructs efficient retrieval, combination, and use of these kinds of information for research and policy-making. Standardization and interoperability are particularly important as many alien species related research and policy activities require pooling data. We describe seven ways that data on alien species can be made more accessible and useful, based on the results of a European Cooperation in Science and Technology (COST) workshop: (1) Create data management plans; (2) Increase interoperability of information sources; (3) Document data through metadata; (4) Format data using existing standards; (5) Adopt controlled vocabularies; (6) Increase data availability; and (7) Ensure long-term data preservation. We identify four properties specific and integral to alien species data (species status, introduction pathway, degree of establishment, and impact mechanism) that are either missing from existing data standards or lack a recommended controlled vocabulary. Improved access to accurate, real-time and historical data will repay the long-term investment in data management infrastructure, by providing more accurate, timely and realistic assessments and analyses. If we improve core biodiversity data standards by developing their relevance to alien species, it will allow the automation of common activities regarding data processing in support of environmental policy. Furthermore, we call for considerable effort to maintain, update, standardize, archive, and aggregate datasets, to ensure proper valorization of alien species data and information before they become obsolete or lost

The pressure of Aphids (Aphididae, Hemiptera), vectors of potato viruses

Plant viruses and aphids as their vectors, are limiting factors in the production of healthy seed potato. Potato Virus Y (PVY) and Potato Leafroll Virus (PLRV) are the two most significant potato viruses in Europe, and seed quality depends directly on the infection level. In order to determine the possibilities for healthy seed potato production in Serbia, aphid flight activities have been monitored for four years in four localities. Over 6400 specimens of aphids have been collected. The number of aphids and vector pressure index varies depending on the localities' altitude. In localities at altitudes under 1000 m, they were high. The highest index was in locality Kotraža in 2007, when the PVY index exceeded the value of 180, while for PLRV it was 60. At high altitudes, above 1100 m, the number of aphids was low, as was the vector pressure index. The lowest index values were recorded in localities on Mt. Golija at 1300 m a.s.l. where the indexes for both viruses never exceeded value 6

Aphids (Hemiptera, Aphididae)

Corresponding authors: Armelle Coeur d’acier ([email protected]),International audienceOur study aimed at providing a comprehensive list of Aphididae alien to Europe. A total of 98 species originating from other continents have established so far in Europe, to which we add 4 cosmopolitan species of uncertain origin (cryptogenic). Th e 102 alien species of Aphididae established in Europe belong to 12 diff erent subfamilies, fi ve of them contributing by more than 5 species to the alien fauna. Most alien aphids originate from temperate regions of the world. Th ere was no signifi cant variation in the geographic origin of the alien aphids over time. Th e average introduction rate was 0.5 species per year since 1800. Th e mean number of newly recorded species per year decreased since 2000 but this pattern may change in the following years

Aphid olfactory responses to volatiles from living plants.

<p>Behavioural responses of winged <i>Myzus persicae</i> in olfactometer experiments when offered choice between (A) volatiles of onion tested and volatiles of potato, (B) volatile mix of onion and potato and volatile mix of two potato plants, and (C) volatiles of onion-exposed potato and volatiles of unexposed potato plants. Asterisks indicate significant preferences * P≤0. 05, Wilcoxon matched pairs test.</p

Volatile emissions of onion exposed and unexposed potato plants.

<p>Mean quantities (+/− SE) of compounds identified from the headspace of onion-exposed and unexposed potato plants. Compound numbers: 1. (<i>E</i>)-2-hexenal; 2. (<i>Z</i>)-3-hexen-1-ol; 3. myrcene; 4. limonene; 5. linalool; 6. (<i>Z</i>)- 4,8-dimethyl-1,3,7-nonatriene; 7. (<i>E</i>)- 4,8-dimethyl-1,3,7-nonatriene; 8. α-copaene; 9. α-cedrene; 10. (<i>E</i>)-caryophyllene; 11. (<i>E</i>)-β-farnesene; 12. (<i>E</i>)-nerolidol; 13. (3<i>E,7E</i>)-4,8,12-trimethyl-1,3,7,11-tridecatetraene; 14. 6,10,14-Trimethyl-2-pentadecanone. * P≤0.05 Least Squares Means.</p

Aphid olfactory responses to synthetic blends of volatile organic compounds of exposed and unexposed potato.

<p>Responses of winged <i>Myzus persicae</i> in olfactometer experiments when presented with synthetic blends based on headspace collections of onion-exposed (treatment) and unexposed potato (control). Synthetic blends were at 1/100, 1/10, 1x, 10x or 100x the original concentration of volatiles identified in potato headspace. Error bars indicate ± SEM. * P≤0.05 Wilcoxon test.</p

Aphid olfactory responses to two terpenoids realised in greater quantities from potato exposed to onion.

<p>Responses of winged <i>Myzus persicae</i> in olfactometer experiments when presented with test solutions containing different doses of (A) (E)-nerolidol, and (B) (3E, 7E) 4, 8, 12-trimethyl-1, 3, 7, 11-tridecatetraene (TMTT), alongside hexane control. Error bars indicate ± SEM. *P≤0.05 Wilcoxon test.</p