Four significant developments have occurred that amplify opportunity for certified organic growers to grow highbush blueberry (Vaccinium corymbosum) successfully. First, there is the 2002 U.S. Department of Agriculture national organic standard that defines organic production practices and crop labels that creates clarity and evens competition. Second, we have the continued increase of smallfruit and vegetable sales related to nutritional and human health reasons and the related market perception valuing organic produce more highly. Third, new tools are becoming available to organic growers that reduce the risk from pest problems such as the recent Organic Materials Review Institute listing of spinosad registered as a wettable powder (Entrust) and a fruit fly bait (GF-120 NF Naturalyte). Finally, the Rutgers Blueberry Working group has made considerable progress in refining integrated pest management practices and in developing new tools for organic production systems. This “work-in-progress” is investigating alternative approaches to some current agricultural practices in soil building, fertility, cultural approaches, and pest management. The authors' 7-year program has demonstrated organic methods in managing new sources of mulch, two key insect pests, two common diseases, and several weed species in establishing a commercial organic production system for highbush blueberries. As a programmatic result, organic acreage in New Jersey has increased from 0 to more than 150 acres, and more than 40 organic growers have adopted parts of this holistic production system in North America.

No abstract

Fourteen tetraploid seedling populations of blackberry (Rubus sp.), representing quadruplex, (TTTT), triplex (TTTt), duplex (TTtt), simplex (Tttt), and nulliplex (tttt) genotypes for the major gene conferring thorniness, were evaluated for segregation of cane thorn density and cotyledonary gland number. Comparisons of seedling distribution curves, means and variances of segregating and non-segregating populations did not show a gene dose effect on gland and thorn occurrence. Inheritance of cotyledonary glands and cane thorns in blackberry was qualitative with the density of glands and thorns apparently controlled by several modifying genes.

Downy Mildew, Plasmopara viticola, causes major damage and economic loss to many wine grape cultivars grown in the Northeast. The purpose of the experiment was to test the efficacy of Vossen Blue (VB; iron pigment) in association with fungicides for the control of Downy Mildew disease of wine grapes in New Jersey. The experimental plot was a planting of `Seyval Blanc' (5th leaf). Treatments (applied via back-pack sprayer) included no fungicide (control I), full fungicide (FF) (RCE commercial recs; control II), FF + 4%VB, FF + 8%VB, 8%VB, Half Rate Fungicide (HF) + 4%VB, HF + 8%VB. There were no significant differences between treatments for total yield, average cluster weight, average berry weight, Brix %, and pH. Spectrophotometric (Hunter's Lab) analysis of foliage samples revealed that leaf samples from the VB treatments had greater green color (correlate: increased chlorophyll). Analysis of subjective (1-9) disease incidence data: FF8 significantly lower disease score that FF; FF4, HF4, HF8, and FF no difference. Compared to normal full fungicide: superior Downy Mildew control was achieved by adding VB to full fungicide; equal control was achieved with half fungicide and VB.

This experiment was conducted in a nonbearing 3-year-old ‘bluecrop’ blueberry field, near Hammonton, NJ. Soils at this location were sandy loam with 4.7 pH and irrigated season long. Blueberry bushes were approximately 3-4 ft tall and spaced 3 × 8 ft apart. Treatments were replicated 6 times in a randomized complete block design with each replicate consisting of 48-ft-long rows with 10-12 bushes in 2 to 4 rows. Treatments were separated by at least 2 unsprayed rows and 4 unsprayed plants within a row that served as buffer. Insecticides were applied as a 1-ft band on both sides of the plant for a total of 96 sq ft of treated area per replication. Granular insecticides were applied by spreading the granules evenly by hand and incorporated to a depth of 1-2 inches using a hand hoe. Liquid formulations were applied with a CO2 pressurized Model T backpack sprayer (R&D Sprayers) equipped with a single TeeJet nozzle (8002VS) operated at 35 psi. Insecticides were applied twice, on 3 Jun and 24 Aug. Insecticides were sprayed using 1.5 liters of water per replicate on 3 Jun and 1 liter on 24 Aug (30—45 gal/acre). Following each application the field was irrigated by drip irrigation with at least 1 inch of water. Treatment effects were evaluated by examining soil and roots in 1-ft-diameter by 1-ft deep areas around the plants (2 plants/replicate) for whitegrubs (including OB, JB, AGB) and mealybugs. Colonies of newly hatched nymphs of mealybugs were counted separately. Plants were sampled between 20-27 Jun following the first application and between 12-19 Sep following the second application.