Abdul Samad, Norani

Universiti Putra Malaysia Institutional Repository

UPM Research Report 1998: Volume 2CUCUMBER MOSAIC CUCUMOVIRUS INFECTIONIN TOMATOES IN THE ABSENCE I PRESENCE OFITS SATELLITE RNANoraniAbdul SamadDepartment of Biochemistry and MicrobiologyUnitlersiti Putra Malaysia, 43400 UPM, Serdang, Selangor,MalaysiaKeywords: cucumber mosaic cucumovirus, tomatoes,satellite RNA.IntroductionTomato (Lycopersicon esculentum Mill), 'universally culti-vated as one of the most important solanaceous vegetablecrops, is being grown as an annual plant worldwide. Cucum-ber mosaic cucumovirus (CMV) is one of the more commonof tomato viruses (Smith, 1972). CMV is among 26 plant vi-ruses which support satellite RNAs (Frisch and Mayo, 1988).These satellite RNAs occur naturally with certain strains ofCMV. They are dependent on CMV for replication and mayeither cause attenuating or aggravating effects on the infec-tivity of CMV. Various combinations of different CMVstrains and different satellite RNAs gave various effectsranging from lethal necrosis, to white chlorosis to diseaseattenuation. In this project, experiments were carried out tostudy the effect of CMV infection in the presence and ab-sence of satellite RNA in eight varieties of tomatoes underglasshouse conditions with the possibility of using satellitesas biological control agents .Materials and MethodsCMV isolate and its satellite RNAused were as described byEl-Sanousi (1997). The experiments were carried out underglasshouse conditions and the plants were grown under dripirrigation system. The tomato plants were mechanically in-oculated at the three-leaf stage with CMV and CMV plus72satellite RNA. Symptoms expressed were graded and calcu-lated as percentage values based on the disease index. Infec-tions by CMV were assayed by double antibody sandwichenzyme-linked immunosorbent assay (DAS-ELISA) (Clarkand Adam, 1977). .Results and DiscussionIn general, the eight varieties of tomatoes studied with CMVand its combination with the satellite RNA showed a widerange of variations. For the disease index, five of the varie-ties tested showed much less severe symptoms in combina-tion with the satellite RNA as compared to those inoculatedwith CMV only. There was a decrease in the DAS-ELISAabsorbance values indicating a significant reduction in viralconcentration of the helper CMV. The other three varietiesshowed an exacerbation of symptoms when inoculated withCMV in combination with the satellite RNA. The DAS-ELISA readings correlated well with the disease indexevaluations.' .ConclusionThe presence of satellite RNA with the helper virus, CMV,showed mixed reactions in the tomato varieties tested.ReferencesClark, M.F. and Adam. A.N. 1977. Characteristics of the microplatemethod of enzyme-linked immunosorbent assay for the detectionof plant viruses. J. Gm. ViroL 34: 475-483.El-Sanousi, O.M. 1997. Differentiation and genetic studies of sev-eral isolates of cucumber mosaic virus. PhD. Thesis, UniversitiPutra Malaysia.Frisch, C. and Mayo, M.A. 1988. Structure and replication. In:PlantViruses Vol.1. Mandahar, C.L (ed.) CRC Pres, Boca Raton,Florida.Smith, K.M. 1972. Textbook of plant virus diseases. Third Edition,Longman.Supported by IRPA Grant Ol ..02-fJ4-OO73

Cucumber mosaic cucumovirus infection in tomatoes in the absence/presence of its satellite RNA

http://psasir.upm.edu.my/18185/1/Cucumber%20mosaic%20cucumovirus%20infection%20in%20tomatoes%20in%20the%20absence%20i%20presence%20of%20its%20satellite%20rna.pdf

Cucumber mosaic cucumovirus infection in tomatoes in the absence/presence of its satellite RNA

Abstract

Similar works

Full text

Available Versions

Universiti Putra Malaysia Institutional Repository