The objective of this study was to examine efficacy of soybean oil dormant sprays to manage San Jose scale (Quadraspidiotus perniciosus Comstock) on apple (Malus ×domestica Borkh.). On 14 Feb. 1994 and again on 20 Feb. 1995, `Bounty' apple trees were: 1) left unsprayed (control) or sprayed to runoff with: 2) 3% (v/v) or 3) 6% degummed soybean oil with 0.6% (v/v) Latron B-1956 sticker spreader, or 4) 3% 6E Volck Supreme Spray petroleum oil. Crawler emergence occurred 17 May-28 June, 7 July-30 Aug., and 7 Sept.-24 Oct. 1994. First-generation crawler emergence had started by 8 May in 1995. Both 3% petroleum oil and 6% soybean oil sprays reduced the numbers of first- and second-generation crawlers by 93% in 1994 and first-generation crawlers by 98% in 1995. The 3% soybean oil treatment reduced first- and second-generation crawlers by 60% in 1994 and first-generation crawlers by 83% in 1995. In 1995, apple fruit infestations by first-generation scales on the 3% soybean-, 6% soybean-, and 3% petroleum oil-treated trees did not differ significantly, but all fruit were significantly less infested than the controls.
Emulsions of degummed soybean (Glycine max L.) oil were compared to a petroleum oil emulsion for efficacy against winter populations of San Jose scale [Quadraspidiotus perniciosus (Comstock); Homoptera: Diaspididae] and European red mite [Panonychus ulmi (Koch); Acari: Tetranychidae] on dormant apple (Malus domestica Borkh.) trees and terrapin scale [Mesolecanium nigrofasciatum (Pergande); Homoptera: Coccidae] on dormant peach [Prunus persica (L.) Batsch.] trees. In laboratory tests, more than 94% of San Jose scale was killed on stems dipped for 1 second in 5.0% or 7.5% soybean oil or 5.0% petroleum oil. Mortality of terrapin scale exceeded 93% on peach stems dipped for 1 second in 7.5% soybean oil or 5.0% petroleum oil. No European red mite eggs survived on apple stems dipped for 1 second in 2.5%, 5.0%, or 7.5% soybean oil, or 5.0% petroleum oil. In field tests, >95% of San Jose scale died on apple trees sprayed with one application of 2.5% petroleum oil or 5.0% soybean oil; two applications of these treatments or 2.5% soybean oil killed all San Jose scales. One or two applications of 2.5% petroleum oil or 5.0% soybean oil killed 85% and 98%, respectively, of the terrapin scales on peach trees. Soybean oil shows promise as a substitute for petroleum oil for winter control of three very destructive fruit tree pests.
Postharvest heat treatments were applied to three apple (Malus domestica Borkh.) cultivars: `Anna', `Golden Delicious', and `Jonathan'. The temperatures ranged from 38 to 50 °C and from 5 to 96 hours. The temperatures of 50 °C for 5 or 10 hours and 46 °C for 10 hours controlled all developmental stages of San Jose scale on `Golden Delicious' and `Jonathan' fruit. Blue mold germination was prevented by 46, 42, and 38 °C after 28, 34, and 42 hours, respectively. The time needed to control the fungus was longer than that required to kill the insect. Apples were damaged by a 50 °C treatment but could withstand at least 12 hours at 46 °C and at least 24 hours at 42 °C. At 38 °C no damage was found on preclimacteric apples even after 96 hours, but if postclimacteric fruit were heated at 38 °C heat damage occurred. The treatments that did not cause damage maintained the fruit firmness during post storage ripening. The results are discussed in the context of developing integrated postharvest heat treatments.
Durations of ultrasound treatments were evaluated for efficacy in removing or destroying external pests of apples (Malus sylvestris var domestica). Egg hatch of codling moth (Cydia pomonella; Lepidoptera: Tortricidae), was inversely related to time of ultrasound exposure, although egg mortality was less than 60% after 45 min of treatment. Mortality of twospotted spider mite (Tetranychus urticae; Acari: Tetranychidae), and western flower thrips (Frankliniella occidentalis; Thysanoptera: Thripidae), was directly related to ultrasound durations; adding detergent to the ultrasound bath increased treatment efficacy. Ultrasound did not remove san jose scale (Quadraspidiotus perniciosus; Homoptera: Diaspididae), from the fruit surface. Ultrasound, which can be incorporated in the packing line, shows promise as a postharvest phytosanitation treatment against external pests.
Abstract
Seventy-five years ago U.S. pomology was caught up in a ferment which marks the ebb and flow of any great agricultural industry. The beginnings of great things to come were in sight, though perhaps unrecognized as such, while the end of other eras was at hand. San Jose scale was being conquered, while peach yellows had destroyed the vast peach industry which bordered the Chesapeake Bay, an industry which made Maryland the leading peach state for a while. The demise of the peach industry was followed shortly by runaway plantings of apples from the mountains of Appalachia westward to Ohio; curiously a similar overexpansion developed in Washington and Oregon as well at that time. South Carolina was just beginning to plant peaches, and it would be 20 years before Michigan would commence peach breeding at South Haven. New Jersey had supported orchard fertilization experiments for 20 years, other Northeastern states for nearly as long. Cultivars were called varieties, and there were great numbers of them in all commercial deciduous fruit orchards. The leading apple cultivar by far was ‘Ben Davis’, but Stark Bros. Nursery had owned Jesse Hiatt's apple for 10 years, and was well under way toward making the 20th century, the ‘Delicious’ century in American apple production. The first high density apple orchard was already 8 years old, this a planting of ‘Wealthy’ trees on seedling rootstocks, spaced 10 × 10 feet, at the Central Experimental Farm in Ottawa, Ontario. But this planting was an idea well ahead of its time, for more than 60 years would pass before the term “high density” would have any meaning in American or Canadian pomology.
calculated by dividing yield by fruit count. Individual fruit were also examined for signs of insect and/or disease injury, and the number of fruit with plum curculio, codling moth, san jose scale ( Quadraspidiotus perniciosus ), oriental fruit moth
armored scale insects Chionaspis pinifoliae and Chionaspis heterophyllae (Hemiptera: Diaspididae) Ann. Entomol. Soc. Amer. 102 381 385 Pless, C.D. Deyton, D.E. Sams, C.E. 1995 Control of San Jose scale, terrapin scale, and European red mite on dormant