BACKGROUND Color morphs of an insect species are known to vary in activities of detoxifying enzymes and associated susceptibility to insecticides. In Diaphorina citri, three color morphs are known to occur. In the present study, susceptibility to four insecticides was compared among gray/brown, blue/green and orange/yellow color morphs of field-collected D. citri. RESULTS The orange/yellow mo...

Radio-(60Co), which emits γ rays, has been used worldwide in pest control. The aim of the present study was to analyze the effect of effective-low-power 60Co-γ irradiation on the enzymatic antioxidant system of the citrus red mite Panonychus citri. One day old female adults were exposed to 0.4 kGy 60Co-γ irradiation and on the, 6th h, 1st day, 2nd day, and 5th day post treatment, the mites were...

Spiroplasma citri, a phloem-limited pathogen, causes citrus stubborn disease (CSD). Losses due to CSD in California orchards have grown over the past decade. To investigate the possibility of introduction or emergence of a new strain, a study of genetic diversity among S. citri strains from various locations was conducted using random amplified polymorphism DNA-polymerase chain reaction (RAPD-P...

The citrus red mite, Panonychus citri (McGregor), is a major citrus pest with a worldwide distribution and an extensive record of pesticide resistance. However, the underlying molecular mechanism associated with fenpropathrin resistance in this species have not yet been reported. In this study, synergist triphenyl phosphate (TPP) dramatically increased the toxicity of fenpropathrin, suggesting ...

PURPOSE As a typical Chinese herbal medicine, Citri reticulatae pericarpium (CRP) possesses various pharmacological effects involved in antioxidant ability. However, its antioxidant effects have not been reported yet. The objective of this work was to investigate its antioxidant ability, then further discuss the antioxidant mechanism. METHODS CRP was extracted by ethanol to obtain ethanol ext...

The helical mollicute Spiroplasma citri, when growing on low-agar medium, forms fuzzy colonies with occasional surrounding satellite colonies due to the ability of the spiroplasmal cells to move through the agar matrix. In liquid medium, these helical organisms flex, twist, and rotate rapidly. By using Tn4001 insertion mutagenesis, a motility mutant was isolated on the basis of its nondiffuse, ...

Direct observation was used to construct activity budgets for Diaphorencyrtus aligarhensis (Shafee, Alam & Agarwal) (Hymenoptera: Encyrtidae) and Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae), foraging for nymphs of Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae). Two populations of D. aligarhensis were used in experiments: a biparental population from Pakistan a...

The Gram-negative bacterium Xanthomonas axonopodis pv. citri, the causal agent of citrus canker, is a major threat to the citrus industry worldwide. Although this is a leaf spot pathogen, it bears genes highly related to degradation of plant cell walls, which are typically found in plant pathogens that cause symptoms of tissue maceration. Little is known on Xac capacity to cause disease and hyd...

*Correspondence: Lukasz L. Stelinski, Entomology and Nematology Department, Citrus Research and Education Center, University of Florida, 700 Experiment Station Road, Lake Alfred, FL 33850, USA e-mail: [email protected] Interactions between plant pathogens and arthropods have been predominantly studied through the prism of herbivorous arthropods. Currently, little is known about the effect of pl...

Alpha-amino-acid ester hydrolases are multimeric enzymes of potential use in antibiotic production. Knowledge of their structure could help to engineer these enzymes into economically viable biocatalysts. The alpha-amino-acid ester hydrolases from Xanthomonas citri and Acetobacter turbidans have been crystallized. The X. citri enzyme crystallizes in a primitive monoclinic space group (unit-cell...