Two New Species of Prαon Haliday (Hymenoptera: Aphidiidae) from Greece

Περιγράφονται δυο νεα είδη στο γε'νος Praon Haliday, το P. staryi spec. nov. και το P. athenaeum spec. nov. To P. staryi καταγράφηκε από την αφίδα Myzus nicotianae Blackman σε Nicotiana tabacum L. To P. athenaeum καταγράφηκε από την αφίδα Hyperomyzus lactucae (L.) σε Sonchus oleraceus L.Two new species of Praon Haliday: P. staryi spec. nov. and P. athenaeum spec. nov., are described. P.staryi was collected and reared from Myzus nicotianae Blackman on Nicotiana tabacum L. and P. athenaeum from Hyperomyzus lactucae (L.) on Sonchus oleraceus L

Insecticidal action of the combined use of spinosad and deltamethrin against three storedproduct pests in two stored hard-wheat varieties.

The combined use of spinosad with deltamethrin against adults of Sitophilus oryzae, Sitophilus granarius and Tribolium confusum was evaluated in a series of laboratory bioassays in two hard wheat varieties (Athos and Sifnos). Two groups of bioassays were carried out. In the first group of bioassays, spinosad or deltamethrin were applied alone at the tested wheat varieties at the doses of 0.01, 0.1 and 0.5 ppm for spinosad and 0.125 ppm for deltamethrin. In the second group of bioassays, the tested wheat varieties were treated with the combination of the above spinosad rates with 0.125 of deltamethrin. In both series of bioassays, mortality of the tested species was evaluated after 7 d of exposure on the treated wheat varieties at 25oC and 65% r.h. Mortality for all species was always significantly higher in Athos than Sifnos. The highest mortality of S. oryzae (73 and 40% for Athos and Sifnos respectively) or S. granarius (88% and 58% for Athos and Sifnos respectively) was recorded in the cases that spinosad was applied alone at 0.5 ppm. On the contrary, in the case of T. confusum, 0.125 ppm of deltamethrin was significantly more effective than any of the application rates of spinosad either when applied alone or in combination with deltamethrin. Despite the fact that the highest mortality of S. granarius adults was recorded after exposure on the wheat varieties treated with 0.1 ppm of spinosad x 0.125 ppm of deltamethrin, in light of the results of the present study, the combination of spinosad with deltmethrin requires further investigation since in most of the tested cases of the present study, single application of spinosad or deltamethrin was more effective or of equal effectiveness than the respective combination of spinosad with deltamethrin. Keywords: Spinosad, Deltamethrin, Tribolium, Sitophilus, Wheat, Variet

Phenology, population trends and natural enemy complex of Illinoia liriodendri in Spain

Illinoia liriodendri (Monell) (Hemiptera: Aphididae) is an Eastern North American native aphid species that infests ornamental tulip trees, Liriodendron tulipifera L. (Magnoliales: Magnoliaceae), in many localities of Spain and southern Europe. This is a comprehensive three-year study on the biology and ecology of the aphid, where its life cycle, phenology, population dynamic trends, comfort damages, natural enemy complex and its potential to control aphid populations have been investigated for the first time in Europe. The monoecic-holocyclic annual cycle of I. liriodendri has been demonstrated. The highest infestation levels were recorded in May and June, but infestation severity varied among localities. No clear trend regarding the effect of planting site (pit vs. ground) on aphid abundance was observed. A strong positive relationship between the aphid infestation severity and the honeydew dripping was recorded. There was a wide complex of natural enemies associated with the aphid. Coccinellidae were the most abundant predators (< 95%) and showed a positive numerical response to the aphid infestation. Several parasitoid species (mainly Hymenoptera: Aphidiinae and Hymenoptera: Aphelinidae) were found parasitizing I. liriodendri in Spain. The role of natural enemies as agents for controlling the aphid populations is discussed.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. R.M. received support through a FPI Grant linked to the project AGL2017- 84127-R, funded by the Spanish Government’s Ministerio de Ciencia e Innovación. F.M. expresses gratitude for national funding provided by the Foundation for Science and Technology (FCT, Portugal) through the institutional scientific employment program contract. The authors would like to thank the Foundation for Science and Technology for their financial support through national funds FCT/MCTES (PIDDAC), CIMO (UIDB/00690/2020 and UIDP/00690/2020), and SusTEC (LA/P/0007/2020).info:eu-repo/semantics/publishedVersio

Mortality and suppression of progeny production of Sitophilus oryzae (L.) (Coleoptera: Curculionidae) and Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) in seven different grains treated with an enhanced diatomaceous earth formulation

DEBBM, an enhanced diatomaceous earth (DE) formulation consisting of a mixture of DE and the plant extract bitterbarkomycin, was applied to seven different grains (wheat, barley, oats, rye, triticale, paddy rice and maize) at two dose rates 50 ppm and 150 ppm. Unsexed, 7d old adults of Sitophilus oryzae (Coleoptera: Curculionidae) and Tribolium confusum (Coleoptera: Tenebrionidae) were exposed to the DEBBM treated commodities and their mortality was assessed after 7d and 14d of exposure at 25 oC and 65% r.h. Furthermore, progeny production of the tested species per treated commodity was also assessed. Sitophilus oryzae appeared to be more susceptible than T. confusum to DEBBM. Performance of DEBBM was better in barley, wheat and oats compared to the remainder of the tested commodities. DEBBM performed better in rye and triticale than in paddy rice against both species although in many cases, significant differences among these grains were not recorded. Despite that DEBBM reached its highest efficacy levels on barley, wheat, and oats it did not suppress progeny production of the treated species in any of the grains. A significant reduction in progeny production of the treated species was recorded in the DEBBM treated grains in comparison with the untreated ones. This reduction in progeny production was expressed more vigorously to S. oryzae rather than T. confusum. In commodities with high DEBBM performance such as barley, oats or wheat, &gt; 9-fold less progeny of S. oryzae were recorded at 150 ppm of DEBBM than in the untreated commodities. Although significantly less progeny of T. confusum were recorded in DEBBM treated grains than untreated grains, progeny suppression of this species was neither dose nor commodity dependant. Keywords: Diatomaceous earth, Bitterbarkomycin, Tribolium, Sitophilus, Mortality, Commodit

Residual Efficacy of Chlorfenapyr for Control of Stored-Product Psocids (Psocoptera)

The residual effect of chlorfenapyr (Phantom) was evaluated for residual control of three stored-product psocid species: Liposcelis bostrychophila Badonnel, Liposcelis entomophila (Enderlein), and Liposcelis paeta Pearman (Psocoptera: Liposcelididae). Chlorfenapyr was applied to individual arenas with a concrete surface at rates of 0, 2.8, 13.8, 20.6, 27.5, 55, and 110 mg active ingredient (AI)/m2. Adults were exposed on the treated arenas and mortality assessed after 1, 2, and 3 d. The procedures were repeated weekly on the same treated arenas for 3 wk to assess residual efficacy. At each week, mortality of all species was low after 1 d of exposure but notably increased after 2 or 3 d. L. entomophila was the most susceptible species, with 99-100% mortality at rates of 13.8 mg/m2 or higher. Similarly, mortality of L. paeta after 3 d of exposure at the same concentration ranged from 92 to 100%. L. bostrychophila was the least susceptible species, with mortality of \u3c60% during the third week after application at rates ≤27.5 mg/m2. However, even for this species, mortality after 3 wk was 90% or higher at rates \u3e27.5 mg/m2. Complete mortality of all species occurred after 3 d exposure at the highest rate tested of 110 mg/m2. Thus, our results show that chlorfenapyr is effective against major psocid species at the application rates evaluated in this study

Lesser grain borers, \u3ci\u3eRhyzopertha dominica\u3c/i\u3e, select rough rice kernels with cracked hulls for reproduction

Tests were conducted to determine whether the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae), selects rough rice (Oryza sativa L. (Poales: Poaceae)) kernels with cracked hulls for reproduction when these kernels are mixed with intact kernels. Differing amounts of kernels with cracked hulls (0, 5, 10, and 20%) of the varieties Francis and Wells were mixed with intact kernels, and the number of adult progeny emerging from intact kernels and from kernels with cracked hulls was determined. The Wells variety had been previously classified as tolerant to R. dominica, while the Francis variety was classified as moderately susceptible. Few F1 progeny were produced in Wells regardless of the percentage of kernels with cracked hulls, few of the kernels with cracked hulls had emergence holes, and little frass was produced from feeding damage. At 10 and 20% kernels with cracked hulls, the progeny production, number of emergence holes in kernels with cracked hulls, and the amount of frass was greater in Francis than in Wells. The proportion of progeny emerging from kernels with cracked hulls increased as the proportion of kernels with cracked hulls increased. The results indicate that R. dominica select kernels with cracked hulls for reproduction

Development of a sampling plan for Myzus persicae (Hemiptera : Aphidoidea) and its predator Macrolophus costalis (Hemiptera : Miridae) on tobacco

A tobacco field in Greece was sampled during the 2001 and 2002 growing seasons to assess the seasonal trends in densities and spatial distributions of the aphid Myzus persicae (Sulzer) and its predatory mirid Macrolophus costalis (Fieber). On repeated occasions between June Oust after the transplantation) and September Oust before harvest), 20 tobacco leaves (10 from the upper and 10 from the lower plant part) were taken from randomly chosen plants. These leaves were sampled for aphids and mirids. In both years, the highest aphid densities were recorded during July and August, while aphid numbers were low in September. In contrast, the majority of M costalis individuals were found during September when aphid numbers were low. Significantly more M persieae individuals were found in the upper part of the plants, whereas significantly more M costalis individuals were found in the lower part of the plants. As indicated by Taylor's Power Law estimates, both species were aggregated in their spatial distributions among sampling units (leaves). Wilson and Room's model, based on the Taylor's estimates, was used to calculate the mean number of aphids and mirids, from the proportion of sampling units (leaves) that had gt 0 individuals of each species. This model provided a satisfactory fit of the data for both the aphid and the mirid. In addition, Wilson and Room's model was successfully used to predict the mean number of aphids and mirids in a series of samples that were carried out in the same area between June and September 2003 for model validation. Finally, equations are given for the calculation of precision in estimating the mean number of aphids or mirids per sampling unit, and the required sample size for a given level of precision

Do temperature, relative humidity and interspecific competition alter the population size and the damage potential of stored-product insect pests? A hierarchical multilevel modeling approach

The premises of stored agricultural products and food consists of a complex ecosystem in which several pests can seriously affect the quality and quantity of the products. In this study we utilize a 4-level hierarchical linear multilevel model in order to assess the effect of temperature, relative humidity (RH) and interspecific competition on the population size and damage potential of the larger grain borer, Prostephanus truncatus (Horn) (Coleoptera: Bostrychidae) and the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae). As RH was increased, we observed higher percentage of live insects, while increased levels of temperature significantly decreased the percentage of live insects. The combination of R. dominica and P. truncatus lead to reduction of the percentages of live insects in comparison to single species treatments. However, P. truncatus is more damaging than R. dominica in maize, based on the proportion of damaged kernels which were infested by each insect species. We expect our results to have bearing in the management of these species

Vrste roda Aphidius nees (hymenoptera, braconidae, aphidiinae) u Srbiji i Crnoj Gori - tritrofičke zajednice i ključ

In the present paper we review 26 Aphidius species from 162 tritrophic associations in Serbia and Montenegro. Aphidius species were reared from over 64 aphid hosts. A key for the identification of species is provided.U radu je dat pregled 26 vrsta roda Aphidius sa 162 različite trofičke zajednice u Srbiji i Crnoj Gori dobijene gajenjem preko 64 afidna domaćina. Dat je i originalni ključ za identifikaciju vrsta roda Aphidius

Chemical composition and broad-spectrum insecticidal activity of the flower essential oil from an ancient Sicilian food plant, Ridolfia segetum

Several species of the family Apiaceae are aromatic herbs that produce essential oils usable on an industrial scale for pharmaceutical, cosmetical and food purposes. Particularly, some essential oils, as green insecticides, may replace synthetic insecticides keeping most of their efficacy and avoiding environmental pollution or human’ poisoning. In the present study, we explored the in-secticidal potential of Ridolfia segetum (L.) Moris essential oil (EO), rich in α-phellandrene (49.3%), β-phellandrene (9.2%), terpinolene (20.7%) and piperitenone oxide (5.9%), against three different pests, Culex quinquefasciatus, Musca domestica and Spodoptera littoralis. For this purpose, the flower EO was obtained by hydrodistillation and its composition was achieved by gas chromatography/mass spectrometry (GC/MS). Concerning mosquitocidal efficacy, the EO showed a noteworthy toxicity against C. quinquefasciatus 3rd instar larvae, with a LC50=27.1 µL L-1 and LC90=42.5 µL L-1. Regarding M. domestica, a different toxicity of the R. segetum EO was found on male and female flies, calculating LD50 values of 10.5 and 50.8 µg adult-1, respectively. The EO was also toxic to S. littoralis 3rd instar larvae, achieving LD50 and LD90 values of 37.9 and 99.6 µg larva-1, respectively. Overall, this flower EO extracted from a traditional Sicilian food plant merits further investigation for the development of green insecticide formulations to be used in the real-world conditions, pending a careful assessment of non-target toxicity on beneficial organisms