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During greenhouse production in Spring 1995, conditioning treatments were applied to columbine (Aquilegia×hybrida Sims `McKana Giants'), New Guinea impatiens (Impatiens hawkeri Bull. `Antares'), marigold (Tagetes erecta L. `Little Devil Mix') and ageratum (Ageratum houstonianum Mill. `Blue Puffs') plants. Treatments included: mechanical conditioning (brushing 40 strokes twice daily); moisture stress conditioning (MSC) (wilting for ≈2 hours per day); undisturbed ebb-and-flow irrigation; overhead irrigation; high (500 mg·L-1 N) or low (50 mg·L-1 N) 3×/week N fertilizer regimes; daminozide (5000 mg·L-1); or paclobutrazol (30, 45, or 180 mg·L-1). One week after initiation of treatments, individual plants in separate greenhouses were inoculated with two adult green peach aphids (Myzus persicae Sulzer) or five two-spotted spider mites (Tetranychus urticae Koch). A natural infestation of western flower thrips (Frankliniella occidentalis Pergande) in the mite-inoculated greenhouse provided an additional insect treatment. Brushing was the only treatment that consistently reduced thrips and mite populations. Aphid populations were lower on low-N than on high-N plants, but thrips and mite populations were not consistently affected by plant fertilization. Moisture stress conditioning tended to increase aphid populations on New Guinea impatiens and marigold, but had little effect on spider mite or thrips populations. Ebb-and-flow irrigation reduced the mite population on ageratum relative to that on overhead irrigated (control) plants. Plant growth regulators did not consistently affect pest populations. Chemical names used: butane-dioic acid mono(2,2-dimethylhydrazide) (daminozide); β-[(4-chlorophenyl)methyl]-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-1-ethanol (paclobutrazol).

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Non-SO2-fumigated `Thompson Seedless' table grapes (Vitis vinifera L.) were stored at 5 or 20 °C for 6 and 4.5 days, respectively, in air or one of four insecticidal controlled atmospheres (ICA); 0.5% O2 + 35% CO2; 0.5% O2 + 45% CO2; 0.5% O2 + 55% CO2; or 100% CO2. The fruit were evaluated for weight loss, berry firmness, soluble solids concentration (SSC), titratable acidity, berry shattering, rachis browning, berry browning, and volatiles (acetaldehyde and ethanol). Fruit quality was not affected at 5 °C with the exception of greater rachis browning in fruit treated with 0.5% O2 + 45% CO2. At 20 °C, ICA treatments maintained greener rachis compared to the air control; however, SSC was reduced in the fruit treated with 55% and 100% CO2. At both temperatures, ICA induced the production of high levels of acetaldehyde and ethanol. Ethanol concentrations were two-thirds lower at 5 °C than at 20 °C. Consumer preference was negatively affected by some ICA treatments for grapes kept at 20 °C, but not by any of the treatments at 5 °C. Preliminary data for mortality of omnivorous leafroller pupae (Platynota stultana Walshingham), western flower thrips (Frankliniella occidentalis Pergande) adults and larvae, and pacific spider mite (Tetranychus pacificus McGregor) adults and larvae indicate that many of the ICA treatments would provide significant insect control.

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This research focused on the influence of insecticides on plant growth, gas exchange, rate of flowering, and chlorophyll content of chrysanthemum (Dendranthema grandiflora Tzvelev cv. Charm) grown according to recommended procedures for pot plant production. Five insecticides were applied at recommended concentrations at three different frequencies: weekly (7 days), bi-weekly (14 days), or monthly (28 days). A separate treatment was applied weekly at 4× the recommended concentration. Insecticides used were: acephate (Orthene®) Turf, Tree & Ornamental Spray 97), bifenthrin (Talstar®) Flowable), endosulfan (Thiodan®) 50 WP), imidacloprid (Marathon®) II), and spinosad (Conserve®) SC). Phytotoxicity occurred in the form of leaf burn on all acephate treatments, with the greatest damage occurring at the 4× concentration. Photosynthesis and stomatal conductance were influenced primarily by the degree of aphid and/or spider mite infestation—except for acephate and endosulfan treatments (weekly and 4×), which had reduced photosynthesis with minimal insect infestations. Plants receiving imadacloprid monthly had the greatest leaf dry mass (DM). Plants treated with acephate had lower leaf and stem DM with bi-weekly and 4× treatments. Spinosad treatments at recommended concentrations had reduced stem DM, in part due to aphid infestations. The flower DM was not significantly different among treatments. There were treatment differences in chlorophyll content as measured with a SPAD-502 portable chlorophyll meter.

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Application of entomopathogenic fungi by inundative releases has been attempted for control of a wide range of insect pests, with generally poor results. This is largely because entomopathogens are often treated as direct substitutes for chemical insecticides and applied without an adequate knowledge of their interactions with the local environment. Humidity of greater than 90% RH has long been regarded as the a critical condition for germination and infection by the spores. With both temperature and humidity controlled, greenhouse crops offer an excellent potential for pest control using entomopathogens. The long-term maintenance of >90% RH, however, is not standard practice in greenhouse production. This study explored the possibility of improving the efficacy of the fungi by temporarily changing greenhouse humidity without adversely affecting crop growth. The study included laboratory and greenhouse trials. In laboratory trials, four humidity levels of 75%, 80%, 89%, and 97.5% RH were evaluated over a 48-h period. Three commercial products of Beauveria bassiana were evaluated (Naturalis-O, Botanigard 22 WP, and Botanigard ES). Greenhouse pests of green peach aphid, melon aphid, western flower thrips, whitefly, and two-spotted spider mite were used as target insects. The infection rate of B. bassiana was found to increase when the sprayed adult insects were exposed to higher humidity levels with the maximum infection obtained at 97.5% RH. Percent infection and difference between humidity levels, however, were formulation- and host-dependent. The highest overall control efficacy was obtained by using Botanigard ES. Botanigard ES was highly effective to adult green peach aphid, melon aphid, and greenhouse whitefly at high humidities. Effects of B. bassiana against biological control agents for greenhouse vegetable crops were also evaluated. Greenhouse trials were conducted in two adjacent greenhouse compartment with high and low humidity conditions for 48 h, respectively, for selected pest insects to valid laboratory results.

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Crabapples ( Malus spp.) are small trees and shrubs in the rose family that are valued for their various types of flowers (single, semi-double, and double forms in shades of purple, red, pink, and white), colorful, small fruits (≤5 cm; primarily

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, flowering crabapples, peonies, plum flowers, and orchids have been elected as the four greatest spring blossoms ( Wang, 2010 ). Unlike some members in the rose family with mutation into double flowers, such as roses ( Bendahmane et al., 2013 ; Dubois et al

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-produced commercial crop, the nobile dendrobiums, hybrids made from Dendrobium nobile , have a high market potential because they produce large amounts of flowers and inflorescences simultaneously ( Rotor, 1952 ). A mature pseudobulb of the nobile dendrobium may have

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by introducing the large-flowered variety called ‘Sensation’ into the Mexicana complex. Plants from the Mexicali complex are believed to have received their winter-hardiness and long bloom from the Penstemon Section Fasciculus and larger flowers

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). Winter-hardy hibiscuses, especially H. moscheutos and its hybrids, have attractive, tropical-looking flowers with a size of 5 to 30 cm in diameter. Winter-hardy hibiscus species are long-day plants ( Warner and Erwin, 2001 ). All species of winter

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, especially H. moscheutos and its hybrids, have attractive, tropical-looking flowers reaching up to 30 cm in diameter. Winter-hardy hibiscus species are long-day plants ( Warner and Erwin, 2001 ) that abundantly produce flowers from midsummer through late

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