A catalogue of aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae) from India

A catalogue of aphidiine parasitoids (Hymenoptera: Braconidae: Aphidiinae) associated with various aphids species occurring in India was compiled. The present catalogue with 125 species under 22 genera has been further reinforced with not only all the latest taxonomic changes but also host names, host plants, distribution in India etc

Spatiotemporal variations in aphid-parasitoid relative abundance patterns and food webs in agricultural ecosystems

Understanding the stability of communities is fundamental in theoretical and applied ecology. Organisms atop trophic chains are particularly sensitive to disturbance, especially when they are dependent on a specific trophic resource subject to strong fluctuations in density and quality, which is the case of parasitoids. We investigated the (1) variability in spatiotemporal relative abundance patterns of a cereal aphid parasitoid community, determining at what scales such patterns vary in agrosystems. We also investigated whether (2) parasitoid relative abundances are strongly influenced by host relative abundances and if (3) different host species are exploited at distinct rates. Aphid parasitoid populations were monitored in three remote agricultural regions in France between 2010 and 2012. Five parasitoid species (Hymenoptera: Braconidae: Aphidiinae) and three aphid species (Hemiptera: Aphididae) were identified in each of those three regions. Fields sampled in one region in a single year exhibited similar relative abundance patterns, with aphid parasitoid communities varying across regions and years. All parasitoid species were able to exploit each monitored host species. Metopolophium dirhodum Wlk was consistently a more frequent species among parasitized aphids than among living aphids, indicating that this aphid species was exploited at a higher rate than the other two aphid species found (Sitobion avenae F and Rhopalosiphum padi L). Those findings suggest the cereal aphid-parasitoid network is not strictly determined by the intrinsic permanent environmental characteristics but partially varies from one year to another. The similarity in abundance patterns in different fields of a region in a given year suggests the existence of a mechanism allowing a rapid synchronisation of the relative abundance patterns at an intra-regional scale. This phenomenon could be useful in predicting host-parasitoid communities and bear important consequences for the ecosystem service provided by parasitoids

The Effects of Different Diets and Transgenerational Stress on Acyrthosiphon pisum Development.

Despite the fact that sap-feeding hemipterans are major agricultural pests, little is known about the pea aphid's (Acyrthosiphon pisum) nymphal development, compared to other insect models. Given our limited understanding of A. pisum nymphal development and variability in the naming/timing of its developmental events between different environmental conditions and studies, here, we address developmental knowledge gaps by elucidating how diet impacts A. pisum nymphal development for the LSR1 strain when it develops on its universal host plant (Vicia faba), isolated leaves, and artificial diet. Moreover, we test how plant age and transgenerational stressors, such as overcrowding and low plant vigor, can affect nymphal development. We also validate a morphological method to quickly confirm the life stage of each nymphal instar within a mixed population. Overall, we found extremely high variation in the timing of developmental events and a significant delay in nymphal (~5-25-h/instar) and pre-reproductive adult (~40-h) development when reared on isolated leaves and artificial diets, compared to intact host plants. Also, delays in development were observed when reared on older host plants (~9-17-h/event, post 2nd instar) or when previous generations were exposed to overcrowding on host plants (~20-h delay in nymph laying) compared to controls

The influence of plant fertilisation regime on plant-aphid-parasitoid interactions

This thesis examines effects of plant fertilisation regime on herbivore and parasitoid performance for two aphids, Macrosiphum euphorbiae and Myzus persicae, and one parasitoid wasp, Aphidius ervi. Herbivore performance was measured as adult fresh weight and intrinsic rate of increase. Parasitoid performance was measured as length of hind tibia, sex ratio, and in a series of choice experiments also parasitoid development time and parasitization rate was measured. Comparisons were made between the performance of M. euphorbiae on two different plant species, petunia and sweet pepper, between the performance of the aphids M. euphorbiae and M. persicae on sweet pepper, and between the performance of A. ervi in M. euphorbiae and in M. persicae on sweet pepper. The performance of M. euphorbiae was better on petunia than on sweet pepper. On petunia a positive effect of plant content of potassium and indications of a positive effect of nitrogen fertilisation were found while on sweet pepper both nitrogen and of potassium had negative influence. On both plant species, however, a negative influence of sulphur was found. The two aphid species reacted differently to fertilisation and plant content of nutrients. For M. euphorbiae fresh weight was decreased by fertilisation while for M. persicae the influence varied with experiment. For M. persicae a high N:K ratio was favourable while for M. euphorbiae plant contents of N and K were both negative. Plant content of sulphur and potassium influenced tibia length of A. ervi positively in M. euphorbiae. In M. persicae plant fertilisation was positive but the composition of the plant fertilisation did not seem important for the parasitoid. Plant fertilisation enhanced parasitization rate in M. euphorbiae but not in M. persicae. Parasitoid performance was, however, more improved by fertilisation in M. persicae than in M. euphorbiae. The parasitoid both preferred, and developed faster in, M. persicae compared to M. euphorbiae. The results of this study show that it is possible to influence both aphid performance and performance of A. ervi with plant fertilisation but the influence varies with both plant and aphid species

Sublethal effects of chlorantraniliprole and thiamethoxam seed treatments when Lysiphlebus testaceipes feed on sunflower extrafloral nectar

Citation: Moscardini, V. F., Gontijo, P. C., Michaud, J. P., & Carvalho, G. A. (2014). Sublethal effects of chlorantraniliprole and thiamethoxam seed treatments when Lysiphlebus testaceipes feed on sunflower extrafloral nectar. Retrieved from http://krex.ksu.eduThe extrafloral nectar (EFN) of sunflower, Helianthus annuus L., is an important summer resource for many insects and represents a potential route of exposure to systemic insecticides applied as seed treatments to cultivated varieties. Among the many parasitoids that utilize sunflower EFN, Lysiphlebus testaceipes (Cresson) (Hymenoptera: Braconidae) is an important generalist parasitoid of cereal aphids in North America. This study evaluated the performance of adult wasps fed EFN of sunflower plants grown from seed treated with chlorantraniliprole and thiamethoxam. Consumption of EFN from treated sunflower seedings caused no lethal effects, but reduced the numbers of greenbug nymphs, Schizaphis graminum Rondani, attacked and parasitized when wasps foraged in Petri dish arenas. Whereas control females self-superparasitized every fourth host, those exposed to chlorantraniliprole did not. Offspring developmental time and adult emergence were unaffected by either treatment, but thiamethoxam greatly reduced the proportion of female offspring

Monoctonus leclanti sp. n. (Hymenoptera: Braconidae: Aphidiinae) from high-montane areas of southeastern Europe, and key to related species

Monoctonus leclanti sp. n., a parasitoid of Delphiniobium junackianum Karsch. (Hemiptera: Aphididae) on Aconitum toxicum bosniacum and Aconitum pentheri in the high mountains of the Balkans is described. The species is an additional member of the high-montane aphid parasitoid guild determined in the area. A key to related species is included

Phylogeny of the Subtribe Monoctonina (Hymenoptera, Braconidae, Aphidiinae)

Abstract: Members of the Monoctonina subtribe have long been neglected in applied studies of the subfamily Aphidiinae, due to their low economic importance, as they do not parasitize pests of cultivated plants. Consequently, data about this group are scarce, including its taxonomy and phylogeny. In the present study, we explore inter- and intraspecific genetic variation of Monoctonina species, including genera Monoctonus Haliday 1833, Monoctonia Starý 1962, Falciconus Mackauer 1959 and Harkeria Cameron 1900. We employ two molecular markers, the barcode region of the mitochondrial cytochrome c oxidase subunit I (COI) and the D2 region of the 28S nuclear gene (28S rDNA), to analyze genetic structuring and phylogeny of all available Monoctonina species, and combine them with morphological data for an integrative approach. We report one new species, and three potentially new species which can be formally described when further specimens are available. Analysis of phylogenetic relationships within the subtribe shows a basal position for the genera Falciconus and Monoctonia, and the close relatedness of Harkeria and Monoctonus

Aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae) of Kashmir, India: a checklist

Se publica una lista de especies de parasitoides afidiinos (Hymenoptera: Braconidae: Aphidiinae) asociados con varias especies de áfidos en Kashmir, India. El trabajo menciona a 61 especies de 15 géneros que se distribuyen en diversas localidades y áreas del valle de Kashmir. La base de datos sobre fauna de áfidos ha sido actualizada con cambios recientes de sistemática, nomenclatura, nombres de hospederos y plantas hospederas. Los parasitoides de áfidos son enemigos naturales de áfidos y pueden ser considerados como potenciales agentes de control biológico. El estudio sistemático de estos parasitoides, ayudará en la implementación de estrategias de manejo para controlar a los áfidos

Phylogenetic relationships and taxonomic status of species of the subtribe Monoctonina (Hymenoptera, Braconidae, Aphidiinae)

Podtribus Monoctonina, sa rodovima Monoctonus, Monoctonia, Falciconus, Harkeria i Quadrictonus, predstavlja jednu od slabije istraţenih grupa u okviru potfamilije Aphidiinae. Vrste podtribusa Monoctonina se od ostalih pripadnika potfamilije morfološki razlikuju po ventralnom membranoznom proširenju legalice. Identifikacija vrsta je oteţana zbog njihovih malih dimenzija tela i nedostatka adekvatnih ključeva za identifikaciju. U okviru podtribusa je do sada opisano 26 vrsta, od čega je 14 zabeleţeno u Evropi. Pored toga što se uglavnom nalaze u malim populacijama, pripadnici Monoctonina su većinom visokoplaninske vrste i naseljavaju staništa listopadnih šuma. Za razliku od većine pripadnika potfamilije, vrste Monoctonina nisu parazitoidi ekonomski značajnih štetočina i ne koriste se u biološkoj kontroli biljnih vaši. U ovoj studiji su analizirani filogenetski odnosi izmeĎu rodova i vrsta podtribusa Monoctonina, kao i status taksona u okviru podtribusa, korišćenjem morfoloških karaktera za identifikaciju vrsta i dva molekularna markera. U analizu su uključeni rodovi Monoctonus, Monoctonia, Falciconus i Harkeria. Za molekularne analize su korišćeni mitohondrijalni gen za citohrom c oksidazu subjedinicu I (COI) i jedarni gen za veliku ribozomalnu subjedinicu 28S (28S rDNK). Morfološkim analizama je utvrĎeno da su najvaţniji karakteri za razlikovanje vrsta unutar podtribusa oblik legalice, oblik pterostigme i duţina metakarpalnog nerva prednjeg krila i broj palpomera labijalnih palpusa. U odreĎenim slučajevima za identifikaciju su značajni i broj flagelomera u antenama, odnos duţine i širine prve flagelomere i prisustvo i oblik petougaone areole na propodeumu. Kombinacijom svih korišćenih metoda utvrĎeno je da rodovi Falciconus i Monoctonia predstavljaju bazalne linije u okviru Monoctonina, koje su se najranije u evoluciji grupe odvojile od ostalih rodova. Rodovi Monoctonus i Harkeria predstavljaju filogenetski vrlo bliske grupe i analizirana vrsta roda Harkeria, H. angustivalva, verovatno pripada rodu Monoctonus. Na osnovu morfoloških i molekularnih analiza opisano je šest novih vrsta, a molekularni podaci ukazuju na postojanje još četiri potencijalno nove vrste ovog podtribusa...Monoctonina, comprising genera Monoctonus, Monoctonia, Falciconus, Harkeria and Falciconus, is one of the least studied groups of the Aphidiinae subfamily. Monoctonina species are morphologically distinguished from other species of Aphidiinae by ventrally widened ovipositor sheaths. Still, species identification is difficult due to small body size and lack of identification keys. There are currently 26 species described within Monoctonina, with 14 of those recorded in Europe. Monoctonina species are most often found in small populations, and inhabit deciduous forest habitats in high mountains. Since aphid hosts of Monoctonina species are not economically important pests, these parasitoids are not usually employed in biological control programs. In this study, we analysed phylogenetic relationships and status of genera and species within the subtribe, using morphological characters and two molecular markers – mitochondrial cytochrome oxidase c subunit I (COI) and nuclear large subunit 28S rDNA. Species from genera Monoctonus, Monoctonia, Falciconus and Harkeria were used in the analysis. Morphological analysis showed that the most relevant character for species identification within Monoctonina are shape of ovipositor, shape of forewing pterostigma and metacarpal vein and number of labial palpomeres. In some cases, number of antennal flagellomeres, length/width ratio of first flagellomere and presence and shape of propodeal areola can be useful. Combination of used methods showed that Falciconus and Monoctonia represent basal lines within the subtribe, which separated early in the evolution of the group. Genera Monoctonus and Harkeria are closely related, and H. angustivalva should probably be moved to Monoctonus. Based on morphological and molecular data, six new species are described, while four potentially new species are uncovered..