Host Range of a Melon Yellowing Virus Transmitted by bemisia tabaci (Gennadius) in Southern Spain

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Cucurbit Genetics Cooperative Report 19:57-58 (article 20) 1996

J.L. Garcia Carrasco, A.I.L. Sese and M.L. Gomez-Guillamon
Experimental Station La Mayora, E-29750 Algarrobo-Costa, Malaga, Spain

To study the host range of a melon yellowing virus transmitted by Bemisia tabaci (Gennadius) in Spain (4), plant species most commonly cultivated in the area, weeds growing near the greenhouse, and two species of Nicoiana were tested.

  • Cucurbitaceae: Cucumis sativus L. cv. Bellpuig, Cucurbita Maxima Duch., Citrullus lanatus (Thunb) Matsum. et Nakai cv. Sugar Baby, Cucurbita pepo L. cv. Negro Belleza.
  • Solanaceae: Lycopersicon esculentum Mill. cv. Daniela, Solanum melongena L. cv. Redonda Negra Lisa, Capsicum annuum L. cv. Italico, Nicotiana tabacum L. cv. Xanthi, Nicotiana benthamiana L.
  • Compositae: Lactuca saiva L. cv. Summer Bibb and cv. Romana, Sonchus oleraceus L.
  • Leguminosaw:Phaseolus vulgaris L., Pisum satiovum L.cv. Alderman
  • Cruciferae: Capsella bursa-pastoris (L.) Medicus
  • Malvaceae: Malva parviflora L.
  • Portulacacea: Portulaca oleracea L.
  • Chenopodiaceae: Chenopodium album L.

Cucumis melo cv. Piel de Sapo was used as a susceptible control. Because the virus was not isolated when the host range was evaluated, controlled inoculations using B. tabaci as the virus vector were carried out in two steps. In the first one, ten seedlings of each species were inoculated using C, melo as inoculum source. A second step was necessary to determine if the virus was present in the inoculated plants of the different species tested. In this step the inoculum sources used were the inoculated plants of the species being tested. Ten seedlings of each species and ten seedlings of melon were inoculated. Controlled inoculations were carried out by placing 60 individuals of B. tabaci on the inoculum source, where they were allowed to feed for 48 hours. Then, the whiteflies were transferred to healthy seedlings and allowed to feed for 72 hours. Whiteflies were then killed and plants were moved to an insect-proof glasshouse to await the appearance of symptoms. Five plants of each species that had never been in contact with whiteflies were used as indicators of possible undesirable inoculations.

Results indicated that the host range of melon yellowing virus transmitted by B. tabaci appears to be restricted to Cucurbitaceae (Table 1). Within this plant family, almost all plants of this species were similar to the ones described in C. melo (2).

Regarding host range and other preliminary results concerning molecular aspects of this virus (Rodriguez-Cerezo, unpublished data), melon yellowing virus in South Spain differs from viruses or strains described in other melon growing areas, such as lettuce infectious yellows virus (LIYV) (1) or cucurbit yellow stunting disorder virus (CYSDV) (3).

Table 1. Incidence of melon yellowing disease in the Cucurbitaceae using different inoculum sources and hosts.

Species

Az

B

C
Citrullus lanatus 10/10y 10/10 10/10
Cucurbita pepo 10/10 — 9/10
Cucurbita maxima 8/10 8/10 10/10
Cucumis savitus 10/10 10/10 10/10
Cucumis melo 10/10 10/10 10/10

z Inoculum source and host genotype: A = C. melo on each species, B = each species on itself, C = each species on C. melo. B. tabaci was used as the virus vector.
y a/b:a = a number of plants with symptoms, b + total plants inoculated, — = data not recorded.

Literature Cited:

  1. Duffys, J.E., R.C. Larsen and H.Y. Liu. 1986. Lettuce infectious yellows virus – A new type of white-fly-transmitted virus. Phytopathology 76:97-100.
  2. Gomex-Guillamon, M.L. y R. Camero. 1993. Es Bemisa tabaci el vector de un nuevo de amarilleo? II Congreso Iberico de Ciencias Horticolas. Zaraoza. Actas de Horticultura 10:1356-1358.
  3. Hassan, A.A. and J.E. Duffus. 1991. A review of a yellowing and stunting disorder of cucurbits in the United Arab Emirates. Emir. J. Ag. Sci., 2: 1-16.
  4. Sese, A.I.L., M.L. Gomez-Guillamon and J.R. Diaz-Ruiz. 19194. Appearance of a possible new melon yellowing disease in Spain. Cucurbit Genetics Cooperative Report, 17: 72-73.