Systematic Studies on the Leafhopper Subfamily Cicadellinae (Hemiptera:Cicadellidae)

Systematic Studies on the Leafhopper Subfamily Cicadellinae (Hemiptera:Cicadellidae)
Author: Daniela Maeda Takiya
Publisher:
Total Pages: 352
Release: 2007
Genre: Hemiptera
ISBN: 9780549097082

Cicadellinae includes approximately 340 genera and over 2,000 species distributed worldwide, with member commonly referred to as sharpshooters. Sharpshooters are specialists on xylem sap, one of the nutritionally poorest diets, along with related cicadas and spittlebugs. Statistical analyses using phylogenetic contrasts of hemipteran body sizes did not show a significant increase in xylem feeding lineages, but results should be viewed cautiously. Sharpshooters host two mutualistic bacterial endosymbionts to complement their poor diet. Phylogenetic analyses were conducted based on the 16SrDNA from Baumannia and Sulcia and on COI, COII, 16SrDNA, and H3 for 29 leafhopper hosts. A congruent evolutionary history of both Baumannia and Sulcia with their sharpshooter hosts is supported based on all (Baumannia) or most (Sulcia ) statistical tests conducted here, suggesting a long-term association of these bacteria with their hosts. Additionally in this thesis, studies on the taxonomy of economically important genus Homalodisca are presented. Finally, incongruence in the higher-level classification of Cicadellinae is mainly due to the lack of robust phylogenetic hypotheses, like the one presented in this thesis. A morphological study based on 183 characters coded for 170 taxa and a molecular study based on partial regions of COI, COII, 16S rDNA, and H3 gene sequences from 91 taxa. Results support changes in the higher-level classification of Cicadellinae including: the erection of the tribe Oncometopiini based on previous members of the Proconiini; the treatment of Phereurhinini within the subfamily Cicadellinae; and placements of 9 genera in different tribes. Furthermore, based on a combined analysis, the origin of the egg-powdering behavior and related sexually-dimorphic morphological characteristics were studied. Results suggest a single origin of the egg-powdering behavior, possibly in the ancestor of Phereurhinini and Oncometopiini. Modifications of the female hindlegs for scraping the brochosomes off onto the egg nests were also acquired once in the ancestor of the Oncometopiini, while modifications on the female forewing setation for better anchoring of brochosome pellets, seem to have been acquired multiple times. Multiple losses of the behavior and its related associated traits occurred in various oncometopiine lineages.

Endosymbiosis of Animals with Plant Microorganisms

Endosymbiosis of Animals with Plant Microorganisms
Author: P. Buchner
Publisher:
Total Pages: 934
Release: 1965-01-15
Genre: Science
ISBN:

Algal symbiosis. Symbiosis with fungi and bacteria. Wrong paths in symbiosis research. Symbiosis in insects feeding on cellulose, herbaceous plant parts, seeds, and similar substances. Symbiosis in animals which live in tree sap. Symbiosis in animals which suck plant juices. Symbiosis in animals sucking vertebrate blood and feeding on corneous substances. Symbiosis in luminous animals. Cases of symbiosis localized in excretory organs. Localization of the symbionts. Methods of transmission. Embryonic and postembryonic phenomena. Correlation between host organism and symbionts. Historical problems. The signioficance of endosymbiosis.

Sucking Pests of Crops

Sucking Pests of Crops
Author: Omkar
Publisher: Springer Nature
Total Pages: 515
Release: 2020-10-12
Genre: Science
ISBN: 9811561494

Sucking pests are most notorious group of pests for agricultural crops. Unlike most pests with chewing mouth parts, sucking pests cause more severe damage to the crops and are complex to get identified until advanced stages of infection. Not only is this late detection detrimental to their effective control, sucking pests also often cause fungal growth and virus transmission. The book emphasizes on sucking pests of most major crops of India. It aims to reflect Indian scenario before the international readership. This book complies comprehensive information on sucking pests of crops and brings the attention of the readers to this multiple damage causing insect complex. The chapters are contributed by highly experienced Indigenous experts from Universities & ICAR institutes, and book collates useful content for students and young researchers in plant pathology, entomology and agriculture.

The Effects of Local and Landscape Context on Leafhopper (Hemiptera: Cicadallinae) Communities in Coffee Agroforestry Systems of Costa Rica

The Effects of Local and Landscape Context on Leafhopper (Hemiptera: Cicadallinae) Communities in Coffee Agroforestry Systems of Costa Rica
Author: Mariange Ramos
Publisher:
Total Pages: 334
Release: 2008
Genre: Coffee
ISBN:

Sharpshooters (Hemiptera: Cicadellidae: Cicadellinae) are potential vectors of Xylella fastidiosa, the bacterial causal agent of coffee "crespera" disease. This study examined the effects of local (shade composition, organic or conventional management, and weed management) and landscape (surrounding land uses) context on sharpshooter communities in coffee agroforestry systems (CAFS) within the Volcánica Central-Talamanca Biological Corridor (VCTBC), in Costa Rica. On a broader perspective, this study also sought to evaluate how the ecosystem service of natural pest control overlaps with other ecosystem services provided by CAFS and how decision makers view these services. The abundance and species richness of sharpshooters were evaluated in four CAFS types present in the VCTBC, using yellow sticky traps and Malaise migration traps in 2005 and 2006. Approximately 73 species of sharpshooters were found in CAFS within the VCTBC. Sharpshooters were more abundant from June to September and declined afterwards. Sharpshooter communities were distinct in each agroforestry system, and coffee sharpshooter communities were more similar to pasture than to forest sharpshooter communities. Shade was a key local variable, negatively affecting sharpshooter abundance. Weed management did not affect sharpshooter communities. Sharpshooters were more abundant at edges of coffee farms, and appeared to move from forests to coffee farms. Surrounding area in forest was positively correlated to sharpshooter abundance. Surrounding area in fallow was positively correlated to species richness. Overlapping of GIS layers of ecosystem services provided by CAFS revealed that there is more land of the VCTBC where natural pest control overlaps with watershed services than with biodiversity services. Interview data showed that natural pest control was more important for decision makers than all other services, except connectivity. Decision makers value ecosystem services in the planning of corridor activities, in addition to location and organization level of corridor areas. Although research is needed on the epidemiology of X. fastidiosa, we found that species that have tested positive for the presence of the bacteria are negatively affected by shade. Increasing shade could be a strategy for management of these species in coffee agroforestry systems. This practice also increases the level of other ecosystem services provided by coffee agroforestry systems.