Resistance to Watermelon Mosaic Virus II Multiplication inCucumis melo

Abstract

PI 96983 was reported to be conditioned by a dominant gene Rsv virus: Classification based on virulence in resistant soybean cultivars. (5). Resistance to all seven SMV strains transferred from PI Phytopathology 69:467-470. 360.844 to the soybean line OX670 was shown to be conditioned by 3. Cho, E. E., and Goodman, R. M. 1982. Evaluation of resistance in a dominant gene Rsv2 (1). From this study, it was not possible to soybeans to soybean mosaic virus strains. Crop Sci. 22:1133-1136. determine if the genes conditioning SMV resistance in PI 483.084 4. Hunst, P. L., and Tolin, S. A. 1982. Isolation and comparison of two and PI 486.355 were different from Rsv2; however, when PI strains of soybean mosaic virus. Phytopathology 72:710-713. 360.844 plants were inoculated with isolate C14, all 20 inoculated 5. Kiihl, R. A. S., and Hartwig, E. E. 1979. Inheritance of reaction to soybean mosaic virus in soybeans. Crop Sci. 19:372-375. plants developed severe necrotic symptoms similar to the reaction 6. Koshimizu, Y., and lizuka, N. 1963. Studies on soybean virus diseases of PI 483.084. Therefore, resistance in PI 483.084 and PI 360.844 in Japan. Tohoku Nat. Agric. Exp. Stn. Bull. 27:1-103. was probably conditioned by the same gene, Rsv2, since reactions 7. Kwon, S. H., and Oh, J. H. 1980. Resistance to necrotic strain of SMV of PI 483.084 and PI 360.844 to all the seven SMV strains and in soybeans. Crop Sci. 20:403-404. isolate C14 were similar. Since the dominant gene in PI 486.355 8. Lim, S. M. 1982. A new source of resistance to SMV in soybeans. differs from the gene in P1483.084, it probably was at a third locus. (Abstr.) Phytopathology 72:943. Further study is needed to compare these genes by evaluating 9. Milbrath, G. M., and Soong, M. M. 1976. A local lesion assay for reactions of the F2 and testcross progeny plants to SMV strains, soybean mosaic virus using Phaseolus vulgaris L. cv. Top Crop.

Virus Transmission by Aphis gossypii Glover to Aphid-resistant and Susceptible Muskmelons

“…Interchange of melon aphid-resistant and susceptible lines as inoculum plants showed that resistance was to transmission rather than to virus acquisition and concurred with the investigation by Romanow et al (1986) and Lecoq et al (1979Lecoq et al ( , 1980. If resistance to virus multiplication reported by Moyer et al (1985) was present in AR HBJ, it was not reflected in our results and perhaps was masked by the high aphid population. Aphid counts seemed high, but a melon aphid resistant : melon aphid susceptible ratio of 1:3 agreed closely with ratios for previous antibiosis studies (Kishaba et al, 1976).…”

“…Because the same gene governs nonacceptance and resistance to virus transmission, they postulated that the same gene also governs antibiosis. Moyer et al (1985) reported resistance to virus multiplication of watermelon mosaic virus (WMV = WMV 2; Purcifull et al, 1984) in a melon aphid-resistant inbred line from PI 371795. One of our melon aphid-resistant Topmark breeding lines, derived from a cross with a different inbred from PI 371795, lacked this resistance.…”

Control of virus infection in crop plants through vector resistance: a review of achievements, prospects and problems

“…, 1979; Moyer et a/., 1985). In addition, an increasing number of reports indicate the potential of even slight vector resistance, especially when combined with some forms of virus resistance (Jones, 1979;Lecoq et al, 1979;1980;Moyer et a/., 1985;Gunasinghe et al, 1988); further studies on the use of such plant material in integrated control programmes involving chemical, cultural and biological methods may increase further the effectiveness of virus control (Text- fig. 6; Lecoq & Pitrat, 1983).…”

“…A . gossypii-resistant muskmelon also has some resistance to mechanical inoculation with, and multiplication of, watermelon mosaic virus 2 (Moyer, Kennedy & Romanow, 1985) but inhibitors are not involved in this resistance.…”

“…Finally, slight vector resistance, though not sufficient alone to provide virus control may, in combination with even slight virus resistance, offer significant improvements in virus control (Moyer et al, 1985;Romanow et al. 1986).…”