Efficacy of fungicides against Phytophthora cactorum on Viola.

Phytophthora cactorum caused significant losses to pansies during the heat wave at the end of the summer of 2006. Infected plants showed foliage that appeared stunted and chlorotic, with wilting occurring even when soil moisture was adequate. When uprooted, symptomatic plants typically possess a surprisingly healthy looking and well-developed root system, but stem and root tissue at the soil interface is discoloured (purple to dark brown) and soft. Older Leaves turn yellow and when the stem base is attacked, the plant dies. Phytophthora cactorum was identified from stem and root tissue with both morphological and molecular techniques. To evaluate the efficacy of different fungicides against this pathogen, healthy plants were infected with zoospores of a Phytophthora cactorum isolate collected from commercial plants. Eleven fungicides were evaluated and compared to an untreated control. Two fungicides were applied via root drenching, 7 days before inoculation with zoospores of P. cactorum. The other fungicides were applied by spraying 24 hours after inoculation with P. cactorum. Preventive drenching with the combined formulation of fenamidone + fosethyl offered the best protection against P. cactorum, while drenching with dimethomorf also resulted in an obvious reduction in the number of infected plants. Foliar application was less successful, as only a combined formulation of mancozeb + metalaxyl-M gave sufficient protection. In conclusion, preventive drenching appears to be the best solution to prevent infection with P. cactorum, especially during warm weather periods, which are conducive to pathogen and disease development.

Control of the two-spotted spider mite (Tetranychus urticae Koch) in glasshouse roses.

Populations of the two-spotted spider mite, Tetranychus urticae, can increase rapidly in glasshouse production, especially during summer. Both chemical and biological control must start at low densities for effective control. The combined efficacy of Phytoseiulus persimilis and the predatory midge, Feltiella acarisuga to control T. urticae on roses was evaluated in 2002. A second year rose crop (Rosa hybrida cv. First Red) was used for this experiment. Two glasshouse compartments of 200 m2 each were used, one was assigned for integrated control and the other for chemical control. The mite populations were monitored by bi-weekly analysis of 12 randomly selected harvestable flower stems, extracted on the Berlese funnel. Sticky plates (3 yellow and 3 blue/200 m2) were used for monitoring the Feltiella adults. End of January a population of +/- 2 spider mites/flower was present in both compartments. In the integrated control, the first Phytoseiulus were released on February the 7th, while the first release of Feltiella was on February the 20th. From week 7 till 13 the population of T. urticae increased exponentially to 90 spider mites/flower stem, while Phytoseiulus population was below one/flower stem. A treatment of fenbutatinoxide + hexythiazox (Torque + Nissuron) was necessary to reduce the spider mite population. A maximum number of predatory mite (4/flower stem) and predatory midge (106 adults/sticky plate) was found only 4 weeks later. A second increase of spider mite population occurred in week 27. Although 2 weeks later 3 predatory mites/flower stem were present, additional chemical treatment was necessary to control. A third and last increase of spider mite occurred in week 39. This last raise could be controlled effectively by Phytoseiulus and Feltiella. Chemical control in the second compartment was effective all-year-round with the exception of week 23 when a major increase up to 60 spider mites/flower stem was found. The applied biocontrol agents could not efficiently control spider mite in glasshouse rose. However, combined with selective insecticides they offer possibilities for IPM in glasshouse roses.

Histopathologic features of vulvar vestibulitis.

Vulvar vestibulitis, a subset of vulvodynia, is present in 15% of patients in a general gynecologic practice. Only a few studies have focused on pathologic features of vulvar vestibulitis and none have included a control group. Punch biopsies from the vulvar vestibule of 12 patients with an age range of 22 to 51 years (mean 28 years) and 12 age-matched controls were analyzed for histopathologic features and investigated for the role of probable etiologic factors including human papillomavirus (HPV). A chronic inflammatory infiltrate was present in all specimens from patients with vestibulitis, and was composed predominantly of T-lymphocytes with a small number of B cells and an admixture of plasma cells, mast cells, and occasional monocytes. T-helper suppressor ratio was normal. The infiltrate was mild in 5 patients, moderate in 1, and severe in 6. Minor vestibular glands were observed in 8 (66%) patients and were associated with a periglandular inflammatory infiltrate. Squamous metaplasia was observed in 4 (44%) patients. Epithelial hyperplasia was present in 10 (83%) patients with mild dysplasia in 2 (16%). Immunohistochemistry for immunoglobulins IgG, IgA, and IgM showed the presence of IgG-positive plasma cells in 75% of patients, suggesting chronic irritation, but an autoimmune etiology cannot be excluded or confirmed. Biopsies of control cases did not show any inflammatory infiltrate. In situ hybridization for HPV 6, 11, 16, and 18 was negative in the patient group as well as in the control group. We conclude that histopathologic abnormalities in patients with vulvar vestibulitis are the result of a chronic inflammatory reaction of the mucosa of the vulvar vestibule, for which the cause remains unclear.

Behavioral approach with or without surgical intervention to the vulvar vestibulitis syndrome: a prospective randomized and non-randomized study.

This article describes the outcome of a behavioral approach with or without preceding surgical intervention in 48 women with the vulvar vestibulitis syndrome. In the first part of the study, 14 women with the vulvar vestibulitis syndrome were randomly assigned to one of two treatment programs: either a behavioral approach or a behavioral approach preceded by surgery. In the second part of the study, 34 women and their partners were given a choice of treatment. Follow-up data were gathered a mean of 3 and 2 1/2 years after treatment, respectively. In the randomized patient population, the intervention had a positive effect on all of them: the complaints disappeared, diminished or did not change but formed less of a problem. The difference in outcome between the two different treatments, a behavioral approach with or without preceding surgery, was not statistically significant. In the second non-randomized part of the study, 28 out of the 34 women (82%) chose the behavioral approach without preceding surgery. The difference in outcome between the two treatments was not statistically significant. Two out of the 28 women who chose behavioral treatment without preceding surgery had to be referred for psychiatric consultation because of serious psycho-sexual problems. In one woman, psychiatric treatment was successful. Three other women, whose behavioral treatment failed, underwent additional surgery, which clearly helped them to overcome the deadlock in the behavioral approach. The behavioral approach should be the first choice of treatment for the vulvar vestibulitis syndrome. Surgical intervention should be considered as an additional form of treatment in some cases with the vulvar vestibulitis syndrome to facilitate breaking the vicious circle of irritation, pelvic floor muscle hypertonia and sexual maladaptive behavior.