Identification of key root volatiles signaling preference of tomato over spinach by the Root Knot Nematode Meloidogyne incognita

The root knot nematode, Meloidogyne incognita (Kofoid and White) Chitwood, is a serious pest of tomato (Solanum lycopersicum) and spinach (Spinacea oleracea) in sub-Saharan Africa. In East Africa these two crops are economically important and are commonly intercropped by smallholder farmers. The rol...

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Autores principales: Murungi, L.K., Kirwa, H., Coyne, D., Teal, P.E., Beck, J.J., Torto, B.
Formato: Journal Article
Lenguaje:Inglés
Publicado: American Chemical Society 2018
Materias:
Acceso en línea:https://hdl.handle.net/10568/97757
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author Murungi, L.K.
Kirwa, H.
Coyne, D.
Teal, P.E.
Beck, J.J.
Torto, B.
author_browse Beck, J.J.
Coyne, D.
Kirwa, H.
Murungi, L.K.
Teal, P.E.
Torto, B.
author_facet Murungi, L.K.
Kirwa, H.
Coyne, D.
Teal, P.E.
Beck, J.J.
Torto, B.
author_sort Murungi, L.K.
collection Repository of Agricultural Research Outputs (CGSpace)
description The root knot nematode, Meloidogyne incognita (Kofoid and White) Chitwood, is a serious pest of tomato (Solanum lycopersicum) and spinach (Spinacea oleracea) in sub-Saharan Africa. In East Africa these two crops are economically important and are commonly intercropped by smallholder farmers. The role of host plant volatiles in M. incognita interactions with these two commodities is currently unknown. Here, we investigate the olfactory basis of attraction of tomato and spinach roots by the infective second stage juveniles (J2s) of M. incognita. In olfactometer assays, J2s were attracted to root volatiles from both crops over moist sand (control), but in choice tests using the two host plants, volatiles of tomato roots were more attractive than those released by spinach. Root volatiles sampled by solid phase microextraction (SPME) fiber and analyzed by gas chromatography/mass spectrometry (GC/MS) identified a total of eight components, of which five (2-isopropyl-3-methoxypyrazine, 2-(methoxy)-3-(1-methylpropyl)pyrazine, tridecane, and α- and β-cedrene) occurred in the root-emitted volatiles of both plants, with three (δ-3-carene, sabinene, and methyl salicylate) being specific to tomato root volatiles. In a series of bioassays, methyl salicylate contributed strongly to the attractiveness of tomato, whereas 2-isopropyl-3-methoxypyrazine and tridecane contributed to the attractiveness of spinach. M. incognita J2s were also more attracted to natural spinach root volatiles when methyl salicylate was combined than to spinach volatiles alone, indicating that the presence of methyl salicylate in tomato volatiles strongly contributes to its preference over spinach. Our results indicate that since both tomato and spinach roots are attractive to M. incognita, identifying cultivars of these two plant species that are chemically less attractive can be helpful in the management of root knot nematodes.
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spelling CGSpace977572024-01-08T18:54:14Z Identification of key root volatiles signaling preference of tomato over spinach by the Root Knot Nematode Meloidogyne incognita Murungi, L.K. Kirwa, H. Coyne, D. Teal, P.E. Beck, J.J. Torto, B. kairomone meloidogyne semiochemical solanum lycopersicum spinacea oleracea The root knot nematode, Meloidogyne incognita (Kofoid and White) Chitwood, is a serious pest of tomato (Solanum lycopersicum) and spinach (Spinacea oleracea) in sub-Saharan Africa. In East Africa these two crops are economically important and are commonly intercropped by smallholder farmers. The role of host plant volatiles in M. incognita interactions with these two commodities is currently unknown. Here, we investigate the olfactory basis of attraction of tomato and spinach roots by the infective second stage juveniles (J2s) of M. incognita. In olfactometer assays, J2s were attracted to root volatiles from both crops over moist sand (control), but in choice tests using the two host plants, volatiles of tomato roots were more attractive than those released by spinach. Root volatiles sampled by solid phase microextraction (SPME) fiber and analyzed by gas chromatography/mass spectrometry (GC/MS) identified a total of eight components, of which five (2-isopropyl-3-methoxypyrazine, 2-(methoxy)-3-(1-methylpropyl)pyrazine, tridecane, and α- and β-cedrene) occurred in the root-emitted volatiles of both plants, with three (δ-3-carene, sabinene, and methyl salicylate) being specific to tomato root volatiles. In a series of bioassays, methyl salicylate contributed strongly to the attractiveness of tomato, whereas 2-isopropyl-3-methoxypyrazine and tridecane contributed to the attractiveness of spinach. M. incognita J2s were also more attracted to natural spinach root volatiles when methyl salicylate was combined than to spinach volatiles alone, indicating that the presence of methyl salicylate in tomato volatiles strongly contributes to its preference over spinach. Our results indicate that since both tomato and spinach roots are attractive to M. incognita, identifying cultivars of these two plant species that are chemically less attractive can be helpful in the management of root knot nematodes. 2018-07-18 2018-10-22T14:49:43Z 2018-10-22T14:49:43Z Journal Article https://hdl.handle.net/10568/97757 en Limited Access American Chemical Society Murungi, L.K., Kirwa, H., Coyne, D., Teal, P.E., Beck, J.J. & Torto, B. (2018). Identification of key root volatiles signaling preference of tomato over spinach by the root knot nematode Meloidogyne incognita. Journal of Agricultural and Food Chemistry, 66(28), 7328-7336.
spellingShingle kairomone
meloidogyne
semiochemical
solanum lycopersicum
spinacea oleracea
Murungi, L.K.
Kirwa, H.
Coyne, D.
Teal, P.E.
Beck, J.J.
Torto, B.
Identification of key root volatiles signaling preference of tomato over spinach by the Root Knot Nematode Meloidogyne incognita
title Identification of key root volatiles signaling preference of tomato over spinach by the Root Knot Nematode Meloidogyne incognita
title_full Identification of key root volatiles signaling preference of tomato over spinach by the Root Knot Nematode Meloidogyne incognita
title_fullStr Identification of key root volatiles signaling preference of tomato over spinach by the Root Knot Nematode Meloidogyne incognita
title_full_unstemmed Identification of key root volatiles signaling preference of tomato over spinach by the Root Knot Nematode Meloidogyne incognita
title_short Identification of key root volatiles signaling preference of tomato over spinach by the Root Knot Nematode Meloidogyne incognita
title_sort identification of key root volatiles signaling preference of tomato over spinach by the root knot nematode meloidogyne incognita
topic kairomone
meloidogyne
semiochemical
solanum lycopersicum
spinacea oleracea
url https://hdl.handle.net/10568/97757
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