Thesis (Ph. D.)--University of Hong Kong, 1967.

published_or_final_version / Zoology / Doctoral / Doctor of Philosophy

Male fig wasps (Hymenoptera: Chalcidoidea) exhibit a fascinating range of morphology and behaviour. A cluster analysis, based on descriptions of the males of several hundred species, distinguished six major morphological groups. Behaviourial observations suggest that male morphology is related to the levels of inter-male aggression. Three behaviourial groupings were identified. Fighting species generally mated in the fig cavity, pacifist species mated in the females' galls or outside the figs. Mating sites are thus the primary determinants of male morphology and behaviour. In fighting species males were larger than their females, whereas pacifists and aggressors were equal in size or smaller than conspecific females. The large males in fighting fig wasps appear to be a consequence of sexual selection because larger males tended to win fights. Within a species there were no differences in the size of the galls that produced males and females, even in species where sexual size differences were present, suggesting that there is a heritable component to wasp size. No alternative advantages for smaller males were detected. Although fights were sometimes fatal, damage was not always a consequence of fighting behaviour and was recorded in both fighting and pacifist species. Sex ratios in several species were more female biased at higher population densities. Sex ratios of species with 'internally' ovipositing species were heavily female biased, but approached 1:1 in more outbred species with 'externally' ovipositing females. Levels of matedness, among females ranged from 73% to 99%. No evidence for sperm exhaustion was obtained. Species of Philotrypesis with both winged and flightless males were present only in southern African Ficus species from subsections Platyphyllae and Chlamydodorae. No species had only winged males. The flightless males of some Philotrypesis species were themselves polymorphic. In one polymorphic Philotrypesis species, winged males were found to be rare at high densities, but common at low densities. Digitata and religiosa males of Otitesella differed in coloration, size and behaviour. Digitata males were aggressors while religiosa males were fighters. Digitata males escaped from the figs whereas religiosa males remained inside the figs, perhaps because only digitata males were attracted to Light. Proportionally more digitata than religiosa males were present in low density populations and females were found to respond differently to the two morphs.

The Sycoecinae are a distinct and well-defined subfamily of old world fig wasps (Agaonidae, Chalcidoidea 1 Hymenoptera) , exclusively associated with the figs of Ficus species (Moraceae). The most likely sister group of the Sycoecinae was determined to be the Sycoryctini (Sycoryctinae) based largely on synapomorphies of the underside of the head. 67 sycoecine species and 3 subspecies were recognised and included in a phylogenetic analysis of the subfamily. This analysis clearly delimited six genera (four African and two extra-African), although the phylogenetic relationships between the genera were not strongly supported and remain flexible. Comparisons of the phylogeny of the Sycoecinae with the classifications of the Agaoninae and their host fig trees (Ficus, Moraceae) suggest a degree of cospeciation sensu lato. Numerous homoplasies were detected within the Sycoecinae, some of which were shared with another group of fig wasps that also enter the fig to oviposit, the Agaoninae. The anatomy of the figs apparently provides strong selection pressures that have resulted in both parallelisms and convergences within and between the two subfamilies. Among the 67 species and 3 subspecies that were recognised, 43 species and 2 subspecies are described as new. The males of three previously recognised species are also described for the first time. One generic and two specific synonyms are established together with five new combinations. Keys are provided to the genera and species, for both sexes.

Previous studies have indicated that certain alfalfa varieties and clones are more resistant than others to alfalfa seed chalcid damage. This resistance varies in all cases and data on infestations indicate that agronomic characteristics may be responsible for some of the apparent resistance. Since this is a major pest in alfalfa seed producing areas, and cultural and chemical controls have been essentially ineffective, it was decided to determine if resistance was associated with certain pod characteristics in order to find a partial solution to the problem.

One of the limiting factors associated with seed production of alfalfa and certain clovers is a small jet-black wasp commonly known as the clover seed chalcid, Bruchophagus gibbus (Boheman). In alfalfa seed producing areas this insect is often referred to as the alfalfa seed chalcid or the alfalfa seed chalcis-fly. In local areas of Utah, farmers often refer to this insect as simply "the fly."

Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed March 16, 2010). Includes bibliographical references. Also issued in print.

Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Includes bibliographical references. Issued in print and online. Available via ProQuest Digital Dissertations.

No description available.

Submitted by Amanda Rodrigues de Souza null (amandarodrigues@fca.unesp.br) on 2016-07-27T19:51:24Z No. of bitstreams: 1 Tese_Amanda_Rodrigues_de_Souza.pdf: 1470066 bytes, checksum: b3e347fb6ccbaf93240df639ac9ce0fa (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-07-29T13:37:56Z (GMT) No. of bitstreams: 1 souza_ar_dr_bot.pdf: 1470066 bytes, checksum: b3e347fb6ccbaf93240df639ac9ce0fa (MD5) / Made available in DSpace on 2016-07-29T13:37:56Z (GMT). No. of bitstreams: 1 souza_ar_dr_bot.pdf: 1470066 bytes, checksum: b3e347fb6ccbaf93240df639ac9ce0fa (MD5) Previous issue date: 2016-05-31 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Plantações de Eucalyptus spp. estão em expansão no Brasil, sendo o país com maior área cultivada do mundo. Contudo, esses plantios vem sofrendo perdas devido ao ataque de insetos-praga, principalmente, as pragas exóticas. A vespa-da-galha do eucalipto, Leptocybe invasa (Hymenoptera: Eulophidae) é um exemplo de invasão. Este inseto se disseminou rapidamente pelos plantios de eucalipto brasileiros a partir de 2008. Neste sentido, estudos são conduzidos para conhecer os aspectos bioecológicos, comportamentais e medidas de controle da praga. O controle biológico tem se mostrado uma medida promissora, principalmente por meio da importação de inimigos naturais, como o parasitoide australiano Selitrichodes neseri (Hymenoptera: Eulophidae). Neste trabalho foram avaliados aspectos da biologia de L. invasa e de seu parasitoide exótico S. neseri, e levantamento populacional de vespas galhadoras em florestas de eucalipto na Austrália. Inicialmente, foram realizados testes de longevidade de fêmeas de L. invasa em diferentes dietas e em sete temperaturas constantes em laboratório, a fim de estimar a sobrevivência deste inseto-praga em diferentes regiões brasileiras. O ciclo de vida de L. invasa foi avaliado em mudas de E. grandis x E. camaldulensis. Em adição, foram avaliados aspectos biológicos do parasitoide S. neseri multiplicados em mudas de eucalipto infestadas por L. invasa em laboratório, com intuito de conhecer a biologia e comportamento do parasitoide. Na última etapa foi realizado o levantamento populacional de espécies de vespas galhadoras em eucalipto na costa leste da Austrália, além de verificar a associação com as espécies de Eucalyptus hospedeiras de importância econômica para o Brasil. A sobrevivência de L. invasa é prolongada com dietas contendo mel, sob temperaturas de 14ºC e 18ºC. A duração média do ciclo de vida de L. invasa foi 87 dias ± 5,3 dias; além disso, o macho de L. invasa também foi registrado no Brasil. A multiplicação do parasitoide S. neseri em laboratório e campo forneceu informações básicas sobre aspectos biológicos desse inimigo natural. Novas detecções de Leptocybe spp. foram registradas nos estados de Queensland e New South Wales, auxiliando o entendimento da distribuição da vespa-da-galha na Austrália. / Eucalyptus spp. plantations are expanding in Brazil, which has the largest area planted in the world. However, these crops have suffered losses due to the attack of insects pest, mainly exotic pests. The blue-gum chalcid, Leptocybe invasa (Hymenoptera: Eulophidae) is a example of invasion. This insect has spread rapidly in the Brazilian eucalyptus plantations after 2008. In this sense, studies are performed to know the bioecological, behavioral aspects and pest control measures. The biological control has proven to be a promising strategy, especially through import of natural enemies such as Australian parasitoid Selitrichodes neseri (Hymenoptera: Eulophidae). In this work, aspects of biology of L. invasa and its exotic parasitoide S. neseri, and population survey of gall wasps on eucalypt forests in Australia of were assessed. Initially, longevity test of L. invasa were performed with different diets and at seven constant temperatures in the laboratory, in order to estimate the survival of this pest insect in different Brazilian regions. The life-cycle of L. invasa was evaluated in E. grandis x E. camaldulensis nurseries. In addition, we assessed the biological aspects of parasitoid S. neseri multiplied in infested eucalyptus seedlings by L. invasa in the laboratory, in order to know the biology and behavior of this parasitoid. In the last step, it was performed the population survey of gall wasps species on eucalypt in East coast of Australia, therefore, to verify the association with the host Eucalyptus species of economic importance to Brazil. The survival of L. invasa is prolonged by providing diets containing honey, and in temperatures of 14ºC and 18ºC. The average duration of life-cycle of L. invasa was 87 days ± 5.3 days, furthermore, the L. invasa male was also record in Brazil. The multiplication of the parasitoid S. neseri in laboratory and field provided basic informations about biological aspects of this natural enemy. New detections of Leptocybe spp. were recorded in Queensland and New South Wales State, helping the understanding about the distribution of blue-gum chalcid in Australia. / CNPq: 142131/2012-1