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Beatriz M. Díaz, Ricardo Biurrún, Aránzazu Moreno, Miguel Nebreda, and Alberto Fereres

Ultraviolet (UV)-absorbing plastic films are being used as a photoselective barrier to control insect vectors and associated virus diseases in different horticultural crops. A 2-year experiment was carried out in northeastern Spain (Navarra) to evaluate the impact of a UV-blocking film (AD-IR AV) on the population density of insect pests and the spread of insect-transmitted virus diseases associated with head lettuce [Lactuca sativa (L.)]. Results showed that the UV-absorbing plastic film did not loose its ability to filter UV radiation after three lettuce crop cycles (14 months). The UV-absorbing plastic film was effective in reducing the abundance and in delaying the colonization of lettuce by aphids [Macrosiphum euphorbiae (Thomas) and Acyrthosiphum lactucae (Passerini)]. A significant increase in the percentage of marketable plants was achieved under UV-absorbing films due to a reduction in the number of plants infested by aphids and by insect-transmitted virus diseases (mainly potyviruses). Also the UV-absorbing plastic films were effective in reducing the population density of Frankliniella occidentalis (Pergande) and the spread of tomato spotted wilt virus (TSWV) as well as the population density of the lepidopteran pest, Autographa gamma (L.), a common pest of lettuce in Spain. However, no effective control of the greenhouse whitefly Trialeurodes vaporariorum (Westwood) was achieved. The results showed that UV-absorbing plastic films are a very promising tool to protect greenhouse lettuce from the main pests and insect-transmitted virus diseases occurring in northeastern Spain.

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W.R. Maluf, L.V. Barbosa, and L. V. Costa Santa-CecÌlia

Oviposition and feeding of Scrobipalpuloides absoluta was studied on plants of seven different genotypes with varying 2-tridecanone (2-TD) foliage concentrations: Lycopersicon esculentum var. glabratum PI 1344417 (GLA), L. esculentum TSWV-547 (ESC), F1 (ESC × GLA), and four F2 genotypes—two with high 2-TD (HI1, HI2) and two with low foliage 2-TD concentrations (LO1, LO2). GLA, HI1, and HI2 showed 2-TD concentrations above 185 × 10–12 mol·cm2, while ESC, LO1 and LO2 had 2-TD below 40 × 10–12 mol·cm2; F1 had intermediary levels of 2-TD (83.5 × 10–12 mol 2-TD/cm2). Ovipositioning was substantially higher in the low 2-TD than on either the high 2-TD genotypes or in the F1, especially in the upper portion of the plants. Scores for leaf lesion type (LLT), overall plant damage (OPD) and percent leaflets attacked (PLA) were substantially higher for the low 2-TD than for either the high 2-TD genotypes or the F1. The results indicate that 2-TD mediates resistance to Scrobipalpuloides absoluta in the interspecific cross, and strongly suggest that 2-TD acts as both an ovipositioning and feeding deterrent for this insect.

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Dilip R. Panthee and Randy G. Gardner

.sp. lycopersici (Sacc.) Snyd. and Hans.] (races 1 and 2), and tomato spotted wilt virus (TSWV). Origin ‘Mountain Majesty’, the F 1 hybrid of NC 714 × NC 1CS ( Fig. 1 ), resulted from a tomato breeding effort to develop a superior large-fruited hybrid tomato with

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Santiago García-Martínez, Adrián Grau, Aranzazu Alonso, Fernando Rubio, Manuel Valero, and Juan J. Ruiz

Pera cultivars are highly susceptible to several viruses such as Tomato mosaic virus (ToMV), Tomato spotted wilt virus (TSWV), and Tomato yellow curl virus (TYLCV) ( Ruiz et al., 2005 ). A breeding program for the introgression of resistance to

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Santiago García-Martínez, Adrián Grau, Aranzazu Alonso, Fernando Rubio, Manuel Valero, and Juan J. Ruiz

strongly ribbed. However, this landrace is severely endangered and at risk of extinction as a result of its high susceptibility to several viruses such as those caused by the Tomato mosaic virus (ToMV), Tomato spotted wilt virus (TSWV), and Tomato

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Dilip R. Panthee and Randy G. Gardner

[ Fusarium oxysporium f.sp. lycopersici (Sacc.) W.C. Snyder and H.N. Hans] races 1, 2, and 3; tomato spotted wilt virus (TSWV); and root-knot nematodes ( Meloidogyne spp.). ‘Mountain Merit’ provides a highly adapted cultivar for North Carolina tomato

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Dilip R. Panthee and Randy G. Gardner

.sp. lycopersici (Sacc.) Snyd. Hans.] (races 1, 2), and Tomato spotted wilt virus (TSWV). It combines the rin and crimson genes, which improve the shelf life and lycopene content of the tomato fruit, respectively. Origin ‘Mountain Lion’, the F 1 hybrid of

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Kevin M. Crosby, Richard L. Fery, Daniel I. Leskovar, and Justin Butcher

(PepMoV). It is homozygous for the Tsw gene that conditions resistance to some strains of TSWV ( Black et al., 1996 ). ‘CaroTex-312’ was evaluated under the experimental designation PX-312 in replicated and/or observational plantings at Charleston, SC

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Dilip R. Panthee and Randy G. Gardner

heterozygous for the I-3 gene for resistance to fusarium wilt race 3 [ Fusarium oxysporum f.sp. lycopersici (Sacc.) Snyd. and Hans.] and the Sw-5 gene for resistance to Tomato spotted wilt virus (TSWV). Fruits are high in soluble solids with an

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Dilip R. Panthee and Randy G. Gardner

blight ( Ph-2 gene) ( Phytophthora infestans Montagne, Bary), and Tomato spotted wilt virus (TSWV) ( Sw-5 gene). It has a compact indeterminate plant with short internodes conferred by the brachytic ( br ) gene and has dark red fruit with high total