SEASONAL BIOLOGY AND CONTROL OF THE DOGWOOD BORER, SYNANTHEDON SCITULA (LEPIDOPTERA: SESIIDAE) ON CLONAL APPLE ROOTSTOCKS IN NEW YORK

The dogwood borer, Synanthedon scitula (Harris), is a relatively new pest problem on apples. Larvae feed principally in burr knots on the above-ground portion of clonal rootstocks. According to a survey of 33 orchards on dwarf or semidwarf apple root-stocks, about 70% of the trees had burr knots. The tendency to develop burr knots was similar among the rootstocks examined in this survey. The proportion of trees infested with dogwood borer in an orchard ranged from 0 to 100% and averaged 30%. The dogwood borer overwinters in the larval stage (2nd to 6th instar) and pupates in the feeding tunnel. Emergence and pheromone-trap records indicate 1 generation a year. In western New York, adults begin to emerge in mid-June, peak in mid-July, and continue to emerge through September. In several tests conducted over a 3-year period, chlorpyrifos at 180 g/100 L provided the most consistent control. At this rate a single spray timed to first or peak egg hatch was as effective as 2 sprays. Latex paint applied by brush to the trunk at the beginning of the oviposition period also reduced the infestation. In established plantings, dogwood borer can also be controlled by berming with soil up to the graft union to prevent access to burr knots. Destroying burr knots chemically with naphthalene acetic acid will not eliminate an infestation and may invite other borer problem

Effect of Spring-Pruning Method, Copper Sprays and Training Systems on Bacterial Canker of Sweet Cherry

Activities: Pruning techniques and bactericides (copper, COCS or Cuprofix Ultra at 4 lb/100 gal, phosphorous acid, Agri-Fos at 2.5 qt/100gal, applied in March and April, or no treatment) were evaluated in bacterial canker field experiments in replicate sweet cherry orchard blocks at the NYSAES, Geneva, NY and the Hudson Valley Lab, Highland, NY (2009 only; no bactericides). In 2008, trees were pruned and inoculated in April. In 2009 and 2010, another experiment was conducted with pruning and inoculation in March, April, May and post-harvest. Pruned branches averaged 3.5 cm diameter and cuts left a stub, average 20-cm-long. In 2008, flush cuts were compared to stub cuts in a separate experiment. Cut surfaces were inoculated with copper-sensitive Pseudomonas syringae pv. syringae (Pss) (10 to the 8th cfu/ml). In 2010, the impact of natural and induced freeze events on canker progression was examined. Canker progression was assessed during the growing season. In 2008, bacteria were re-isolated from inoculated cuts and Pss identified with biochemical and PCR assays. In 2008, the efficacy of phosphite or copper against leaf scar infections generated by inoculating branches at 80 percent leaf drop was tested and bud blast assessed. In the 2008-2009 dormant season, six sweet cherry orchard planting systems and five cultivars were assessed visually for incidence of cankers to rate relative susceptibility. Laboratory experiments with detached shoots and green cherry fruit were conducted to determine pre-infection and post-infection activity of labeled or specified rates of copper hydroxide (standard), phosphite, Pentra Bark, kasugamycin, biological MOI-106, biological yeast in proprietary buffer, oxytetracycline, urea, Bacillus subtilis, and hydrogen dioxide against Pss, compared to untreated. The isolate of Pss used for inoculum in the field experiments (Ps34 collected by Burr from sweet cherry, Wayne County, NY) was submitted for genome sequencing. Three naturally-occurring, streptomycin resistant isolates of Pss were recovered from apple buds in Geneva, NY. Events: A 2009 Sweet Cherry Field Meeting and a 2010 Summer Fruit Tour held at NYSAES, Geneva, NY featured our research, reaching over 240 sweet cherry growers, nurserymen, industry personnel, consultants, educators and faculty. Services: We ruled out bacterial canker outbreaks at three orchards and verified bacterial canker at three orchards. Products: Copper and phosphite are essentially ineffective against bacterial infections of pruning cuts, pruning stubs may effectively contain canker infections, and cankers progress least when pruning is done after harvest. Flamout and Kasumin show activity against Pss infection in sweet cherry. We have a collection of contigs for the Ps34 genome and a physical collection of 420 Pss isolates. Dissemination: Carroll provided research results to Cornell Cooperative Extension for summer and winter fruit schools for farmers and presented project results to scientists at the American Phytopathological Society, the Great Lakes Fruit Workers, and the Cumberland-Shenandoah Fruit Workers meetings

Variações morfológicas intra e interpopulacionais de Euseius citrifolius Denmark & Muma e Euseius concordis (Chant) (Acari, Phytoseiidae) Intra and interpopulational morphological variations of Euseius citrifolius Denmark & Muma and Euseius concordis (Chant) (Acari, Phytoseiidae)

<abstract language="eng">The determination of morphologic variability within and between populations of phytoseiid mites is important for the precise species identification. Euseius citrifolius Denmark & Muma, 1970 and Euseius concordis (Chant, 1959) are phytoseiids commonly found on different crops in Brazil and other South American countries. The morphologic characterization of populations preliminarily identified as E. citrifolius and E. concordis was done through examination of 10 adult females and 10 adult males of each population and of 2 to 10 adult females and males resulting from crosses between those populations. The plant substrate and collection site of each population were: E. citrijolius: Bauhinia sp. in Arroio do Meio, Rio Grande do Sul, Coffea arabica Linnaeus in Campinas, São Paulo and Terminalia catappa Linnaeus in Petrolina, Pernambuco. E. concordis: Passiflora edulis Sims. i.flavicarpa Deg. in Arroio do Meio, Manihot esculenta (Crantz) in Jaguariúna, São Paulo, Hevea brasiliensis Muell. Arg. in Pontes e Lacerda, Mato Grosso, T. catappa in Petrolina and C arabica in Viçosa, Minas Gerais. A comparison of the measurements of different structures of individuals of each population and of type specimens of E. citrifolius and E. concordis confirmed the preliminary identification of the populations. Significant relationships were observed between mean setal lengths and the respective ranges within each population. Females and males of E. citrifolius from Petrolina and E. concordis from Jaguariúna had some of the setae generally shorter than those of other populations of the same species. Measurements of males resulting from heterogamic crosses indicated that E. citrifolius and E. concordis reproduce by pseudo-arrhenotoky