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Serge Overney, Dominique Michaud, Binh Nguyen-Quoc and Serge Yelle

In recent years, several studies have demonstrated the potential of proteinase inhibitors (PIs) for controlling insect pests. Used as a component of an integrated pest management program, such an approach must, however, be considered with care, given the potential risks of interference on other control approaches. In particular, the effect of PIs on digestive proteinases of beneficial insects must be determined. As an example, this study analyzed the effect of oryzacystatins (OCs), two cysteine PIs isolated from rice, on digestive proteinases of Perillus bioculatus, a predator of the Colorado potato beetle (CPB; Leptinotarsa decemlineata Say), a major pest. Electrophoretic analyses showed the existence of several cysteine proteinase forms in the digestive tract of P. bioculatus. For each developmental stage, OCs dramatically inhibited proteolytic activity, showing an affinity between these inhibitors and the digestive proteinases of the predator. Despite their potential for controlling CPB, the two rice cystatins thus represent possible growth-suppressing compounds for the beneficial insect P. bioculatus. Work is currently under way to assess the compatibility of the two control approaches.

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Liming Chen, Matthew Wallhead, Michael Reding, Leona Horst and Heping Zhu

≈16 and 11 times in 1 year, respectively, and blueberry and black raspberry need to be sprayed approximately seven and five times, respectively. For applying pesticides to control insect pests and diseases in fruit farms, the most commonly used spray

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Sam Marshall, David Orr, Lucy Bradley and Christopher Moorman

cover throughout the United States and a low tolerance for weed and insect pests coincides with an increase in the use of synthetic chemicals ( Alumai et al., 2008 ). Conventional lawn management strategies are calendar-based applications of synthetic

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Heather S. Costa, Julie Newman and Karen L. Robb

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Alfred Jones

Sweetpotato [Ipomoea batatas (L.) Lam.] cultivars with high levels of resistance to root damaging insects have been developed through the collaborative efforts of a multidisciplinary research team. These resistances were combined with other traits necessary for a successful cultivar such as: disease resistances; high yield; long storage life; prolific sprout production; marketable root size, shape and skin at tributes; and culinary excellence. Adpotion of quantitative genetic principles, development of a wide gene base, sequential selection schemes, use of effective selection criteria and appropriate susceptible standards contributed to the program's success. These achievements were made with, little prior knowledge about inheritance patterns, gene action, mechanisms of resistance or a complete knowledge of the insects concerned. The value of insect resistant cultivars has become better appreciated with the recent decrease in chemical alternatives.

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Alfred Jones

Sweetpotato [Ipomoea batatas (L.) Lam.] cultivars with high levels of resistance to root damaging insects have been developed through the collaborative efforts of a multidisciplinary research team. These resistances were combined with other traits necessary for a successful cultivar such as: disease resistances; high yield; long storage life; prolific sprout production; marketable root size, shape and skin at tributes; and culinary excellence. Adpotion of quantitative genetic principles, development of a wide gene base, sequential selection schemes, use of effective selection criteria and appropriate susceptible standards contributed to the program's success. These achievements were made with, little prior knowledge about inheritance patterns, gene action, mechanisms of resistance or a complete knowledge of the insects concerned. The value of insect resistant cultivars has become better appreciated with the recent decrease in chemical alternatives.

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Richard L. Fery

The use of multidisciplinary teams has been the key to making progress in the development of insect resistant southernpea [Vigna unguiculata (L.) Walp.] and tomato (Lycopersicon esculentum Mill.) cultivars; both the plant breeder and the entomologist have primary program responsibilities. The basic approach encompasses three separate but interrelated phases: 1) evaluation of germplasm collections to locate needed sources of resistances, 2) genetic studies to determine the inheritance of resistances, and 3) breeding programs to transfer resistance genes into adapted germplasm. The basic approach must usually be supplemented by concurrent research to, determine the nature and value of resistances and to develop evaluation procedures, selection criteria, and plant breeding methodologies. Selected examples from research projects on southernpea (resistances to cowpea curculio, southern green stinkbug, leaf footed bug, leaf miners, and thrips) and tomato (resistances to tomato fruitworm, tobacco hornworm, and Colorado potato beetle) will be used to illustrate approaches and methodologies.

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A.A. Csizinszky, D.J. Schuster and J.B. Kring

Field studies were conducted for three seasons, Fall 1988 and Spring and Fall 1989, on the effect of six mulch colors: blue, orange, red, aluminum, yellow, and white (fall) or black (spring), on fruit yields and on insect vectors of Sunny' tomato (Lycopersicon esculentum Mill.). Plant growth and yields were inconsistent with mulch colors during the three seasons. In Fall 1988, in a once-over harvest, extra-large (≥ 70 mm diameter) and marketable fruit yields were higher (P ≤ 0.05) on blue than on the conventional white mulch. In Spring 1989, early marketable yields on red mulch were higher than on black mulch, and in Fall 1989, under high stress from tomato mottle virus (TMoV) transmitted by silverleaf whitefly [Bemisia argentifolii (Bellows and Perring)], seasonal yield of extra-large fruit was better on orange than white mulch. In Fall 1988 and 1989, fruit size and marketable yields were reduced on yellow mulch. Aphids (Aphididae), thrips (Thripidae), and whiteflies were counted monthly in traps placed on the mulched beds. Aphids were least numerous on the aluminum and yellow and most numerous on the blue mulch. Where differences occurred, the fewest thrips were captured on aluminum and the fewest whiteflies were captured on the yellow, aluminum and orange mulches. Although differences were not always significant, the fewest adult whiteflies also were observed on foliage of tomato plants grown on these latter three mulches. Later in the seasons, as plant foliage covered the mulch, differences in the number of insects captured were similar for all mulch colors. Low numbers of whiteflies on the orange and aluminum mulches early in Fall 1989 delayed virus symptom development and increased yields. Virus symptom development was not delayed and yields were low on the yellow mulch, in spite of the low number of whiteflies. When averaged over all mulch colors, extra-large and marketable fruit yields increased linearly with delayed symptom development. It is proposed that, under high insect stress, mulches should be selected for their effects on insects in addition to their effects on soil temperature and plant morphology.

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K.C. Shellie, L.G. Neven and S.R. Drake

Sweet cherries (Prunus avium `Bing') exposed to 113 or 117 °F (45 or 47 °C) in an atmosphere of 1% oxygen with 15% carbon dioxide (balance nitrogen) were heated to a maximum center temperature of 112 or 115 °F (44 or 46 °C) in 41 or 27 min, respectively. Heated cherries had similar incidence of pitting and decay, and similar preference ratings after 14 days of storage at 34 °F (1 °C) as nonheated or methyl bromide fumigated fruit. Heated cherries and methyl bromide fumigated cherries were less firm after 14 days of cold storage than nonheated, control fruit. The stems of methyl bromide fumigated cherries were less green than heated or nonheated cherries. Cherries exposed to 113 °F had lower titratable acidity than nonheated cherries, fumigated cherries, or cherries exposed to 117 °F. Cherry quality after 14 days of cold storage was not affected by hydrocooling before heating (5 min in water at 34 °F) or by method of cooling after heating (hydrocooling, forced air cooling, or static air cooling). Cherries stored for 14 days at 34 °F in 6% oxygen with 17% carbon dioxide (balance nitrogen) had similar market quality as cherries stored in air at 34 °F. Results suggest that `Bing' sweet cherry can tolerate heating in an atmosphere of low oxygen containing elevated carbon dioxide at doses that may provide quarantine security against codling moth (Cydia pomonella) and western cherry fruit fly (Rhagoletis cingulata).

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David A. Bender and William P. Morrison

Indian mustard trap crops have successfully reduced pesticide use on commercial cabbage in India. Diamondback moth has been a serious pest of cabbage in Texas and has demonstrated resistance to most classes of insecticides. Use of a trap crop could fit well in an integrated management program for cabbage insects, Three-row plots of spring and fall cabbage were surrounded by successive single-row plantings of Indian mustard in trials at Lubbock, Texas to determine the efficacy of interplanting for reducing insecticide applications. Insects in the cabbage and Indian mustard were counted twice weekly, and insecticides were applied selectively when economic thresholds were reached. Indian mustard was highly attractive to harlequin bugs, and protected intercropped spring cabbage. Cabbage plots without mustard required two insecticide applications to control the infestation. False chinch bugs were also highly attracted to Indian mustard. Lepidopterous larvae, including diamondback moth, did not appear to be attracted to the trap crop. Indian mustard trap crops reduced insecticide applications to spring cabbage but had no positive effect on fail cabbage.