Evaluation of wild tomato accessions (<Emphasis Type="Italic">Solanum</Emphasis> spp.) for resistance to two-spotted spider mite (<Emphasis Type="Italic">Tetranychus urticae</Emphasis> Koch) based on trichome type and acylsugar content

Tomato wild relatives are important sources of resistance to many pests of cultivated tomato [Solanum lycopersicum L. (syn. Lycopersicon esculentum Mill.)]. Eleven wild tomato accessions previously identified at AVRDC—The World Vegetable Center as resistant to Bemisia tabaci were evaluated for resistance to the two-spotted spider mite [Tetranychus urticae (Koch.)] based on egg numbers using the leaf disc and Tanglefoot no-choice bioassays, and damage scores in choice bioassays. Highest resistance based on choice and no-choice bioassays was identified in AVRDC S. galapagense accessions VI057400, VI045262, VI037869 and VI037239, and S. cheesmaniae accession VI037240, all of which are new sources of T. urticae resistance. In addition, S. pimpinellifolium accession VI030462 exhibited resistance only in the no-choice bioassay based on egg numbers. Resistance to T. urticae based on the number of eggs from the no-choice bioassays was positively correlated with density of type IV glandular trichomes and negatively correlated with densities of type V trichomes. All resistant accessions accumulated high levels of total acylsugars, which were positively associated with type IV trichomes. There was a significant negative relationship between acylsugar content and T. urticae egg numbers from the no-choice bioassays. There was high correlation between the results from the leaf disc test and the Tanglefoot no-choice bioassay. These findings support the possible presence of broad-based insect and mite resistance in accessions closely related to cultivated tomato.     

Minor cultures as hosts for vectors of extensive crop diseases: Does <Emphasis Type="Italic">Salvia sclarea</Emphasis> act as a pathogen and vector reservoir for lavender decline?

Stolbur is a phytoplasma disease affecting crops worldwide. The planthopper Hyalesthes obsoletus is the main natural vector of ‘Candidatus Phytoplasma solani’ responsible of stolbur. In France, lavender (Lavandula angustifolia) and lavandin (Lavandula × intermedia) are strongly affected by this phytoplasma. These plant species are both hosts for the phytoplasma and its insect vector. In 2011, catches of adults were exceptionally sizable on one of the clones of lavandin most tolerant to lavender decline. A high population level of ‘Ca. P. solani’ vector was also observed on the adjacent plot of clary sage, Salvia sclarea. In order to clarify the potential role of S. sclarea as a host plant for H. obsoletus and ‘Ca. P. solani,’ we conducted field surveys and laboratory experiments. The uprooting of clary sage and root examination showed the presence of nymphs during winter. Harvested nymphs have been reared on S. sclarea from seedlings in a greenhouse for many generations. By performing its whole lifecycle on clary sage, we demonstrated for the first time that S. sclarea is a host plant of H. obsoletus and could be a source of stolbur vector. Nevertheless, status of clary sage as host plant of phytoplasma in the field up to now is not so clear. On 42 Q-PCR runs done on S. sclarea, 41 were negative to the phytoplasma, and one positive. Experimental transmission with infected H. obsoletus sampled on infected lavender showed that clary sage plant could be infected, expressed symptoms and multiplied ‘Ca. P. solani.’     

Lack of enhanced oxygen consumption by polymorphonuclear leukocytes on phagocytosis of virulent Salmonella typhi

Human polymorphonuclear leukocytes exhibit an enhanced rate of oxygen consumption during phagocytosis of relatively avirulent strains of Salmonella typhi or Staphylococcus aureus. However, phagocytosis of a virulent strain of Salmonella typhi is not associated with augmented oxygen consumption. The ability of a bacterial strain to alter the postphagocytic rate of oxygen consumption of polymorphonuclear leukocytes may be related to its in vivo virulence.     

Intranasal infusion of enilconazole for treatment of sinonasal aspergillosis in dogs

OBJECTIVE: To determine effectiveness of infusion of 1 and 2% enilconazole for treatment of nasal and sinusal aspergillosis, respectively, in dogs. DESIGN: Case series. ANIMALS: 26 client-owned dogs with aspergillosis. PROCEDURE: All dogs had typical clinical signs of aspergillosis and rhinoscopically visible intrasinusal or intranasal fungal plaques associated with turbinate destruction. During rhinoscopy, affected nasal cavities and frontal sinuses were debrided meticulously. Nineteen dogs (group A) were treated with 1% enilconazole by use of a modified noninvasive infusion procedure. Seven dogs (group B) were treated with 2% enilconazole via catheters that were placed via endoscopic guidance into the frontal sinuses. All dogs underwent follow-up rhinoscopy for determination of further treatment until cure was established. RESULTS: Age, disease duration, clinical score, and rhinoscopic score were similar for both groups before treatment. In group A, 17 of 19 dogs were cured; 9, 6, and 2 dogs were cured after 1, 2, or 3 treatments, respectively. The remaining 2 dogs were euthanatized before the end of the treatment protocol. In group B, all dogs were cured; 6 dogs and 1 dog were cured after 1 or 2 treatments, respectively. Only minor adverse effects such as nasal discharge, epistaxis, and sneezing developed. CONCLUSIONS AND CLINICAL RELEVANCE: After extensive rhinoscopic debridement, 1 and 2% enilconazole infused into the nasal cavities and the frontal sinuses, respectively, were effective for treatment of aspergillosis in dogs. Intrasinusal administration via endoscopically placed catheters appeared to require fewer infusions for success. Follow-up rhinoscopy is strongly advised.     

Occurrence and distribution of ‘Candidatus Phytoplasma trifolii’ associated with diseases of solanaceous crops in Lebanon

A survey for phytoplasma diseases in tomato and pepper fields in Lebanon was conducted during 2003 and 2004. Tomato plants with stunting, yellowing or purplish leaves, proliferation of laterals buds, hypertrophic calyxes and virescent flowers were found in 25% of the tomato fields surveyed, where they represented 2–8% of the plants. Pepper plants displaying stunting and yellowing of leaves, were found in 27% of the fields and 1–4% of the plants were affected. Phytoplasmas infecting tomato and pepper had identical 16S-rDNA RFLP profiles and sequences. A phytoplasma isolate named PTL was transmitted by dodder from a diseased tomato plant to a periwinkle (Catharanthus roseus) plant in which it induced leaf yellowing, virescence and phyllody. 16S-rDNA phylogenetic analysis classified PTL as a strain of ‘Candidatus Phytoplasma trifolii’.