Search Results

You are looking at 31 - 40 of 53 items for :

  • Refine by Access: All x
Clear All
Free access

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.

Free access

M.J. Díez, S. Roselló, F. Nuez, J. Costa, M.S. Catalá, and A. Lacasa

Seedlings of three tomato (Lycopersicon esculentum Mill.) cultivars [`RDD', carrier of the Sw5 gene, which confers resistance to tomato spotted wilt virus (TSWV); `Pitihué', tolerant to the virus; and the susceptible cultivar Rutgers] were placed at the four- to five-leaf stage in cages containing a population of viruliferous thrips (Frankliniella occidentalis Perg.), and remained there for 0, 7, or 15 days. Plants were subsequently transplanted either into the open field or in tunnels protected with a mesh of 14 × 10 threads/cm. Systemic symptoms and number of dead plants were recorded and enzymelinked immunosorbent assays (ELISA) were performed. `Rutgers' exhibited severe systemic symptoms regardless of treatment and a high number of plants died. The level of infected plants remained low when protective measures were applied to seedlings of `Pitihué' and acceptable yields were obtained. In open air cultivation, where seedling infection was severe, <20% of `RDD' plants became infected and high yields were obtained; protected cultivation did not reduce yield. Although the percentage of infected plants was higher when cultivated under mesh, the yield of all three cultivars was greater than in the open field. The environment created under mesh stimulated growth, neutralizing the effect of the infection.

Free access

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

Free access

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

Free access

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

Free access

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

Free access

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

Free access

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

Free access

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

Free access

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