Bulletin of Entomological Research (2000) 90, 161-167

G. Nombela, F. Beitia and M. Muñiz (2000)
Variation in tomato host response to Bemisia tabaci (Hemiptera: Aleyrodidae) in relation to acyl sugar content and presence of the nematode and potato aphid resistance gene Mi
Bulletin of Entomological Research 90 (2), 161-167
Abstract: Two commercial cultivars of tomato, Alta and Peto 95, the accession line number LA716 of Lycopersicon pennellii and lines 94GH-006 and 94GH-033 (backcrosses between Peto 95 and LA716), with different leaf acyl sugar contents were screened for resistance to Bemisia argentifolii Bellows and Perring (corresponding to the Spanish B-biotype of Bemisia tabaci (Gennadius)), in greenhouse- and field-no-choice experiments. There was no oviposition on LA716 (with the highest acyl sugar content) while the greatest fecundity and fertility values were observed on the cultivar Alta (no acyl sugar content). However, no clear relationship was found between the low acyl sugar content in the other tomato cultivars tested and whitefly reproduction. Thus, resistance to B. tabaci did not appear to correlate with acyl sugar content below a threshold level of 37.8 µg cm^-2leaf. In a greenhouse choice-assay, B. tabaci exhibited reduced host preference and reproduction on the commercial tomato cultivars Motelle, VFN8 and Ronita all of which carry the Mi gene resistance to Meloidogyne nematodes and the aphid Macrosiphum euphorbiae (Thomas), than on the Mi-lacking cultivars Moneymaker, Rio Fuego and Roma. When data of Mi-bearing plants were pooled, the mean values for daily infestation and pupal production of B. tabaci were significantly lower than those of Mi-lacking plants. This reflected a level of antixenosis- and antibiosis-based resistance in commercial tomato and indicated that Mi, or another closely linked gene, might be implicated in a partial resistance which was not associated either with the presence of glandular trichomes or their exudates. These findings support the general hypothesis for the existence of similarities among the resistance mechanisms to whiteflies, aphids and nematodes in commercial tomato plants.
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Link to article at publishers website
Database assignments for author(s): Gloria Nombela, Mariano Muniz

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host
environment - cropping system/rotation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Bemisia tabaci biotype MEAM1	Tomato (Solanum lycopersicum)	Spain (continental)