1.11.21
BIOLOGICAL CHARACTERIZATION AND SEQUENCE ANALYSIS OF AN INDONESIAN ISOLATE OF CUCUMBER MOSAIC CUCUMOVIRUS

A KAWAGUCHI1, G SUASTIKA2, T NATSUAKI2 and KT NATSUAKI1

1Faculty of Agriculture, Tokyo University of Agriculture, Sakuragaoka, Tokyo, 156-8502 Japan; 2Faculty of Agriculture, Utsunomiya University, Minemachi, Utsunomiya, 321-8505 Japan

Background and objectives
While at least 11 plant species were reported to be infected by cucumber mosaic cucumovirus (CMV) in Indonesia [1], only a few Indonesian CMV isolates were characterized precisely. A series of survey to detect CMV from various plants were conducted and an isolate of CMV (CMV-I) was obtained from tobacco in West Java. The objective of this study is to report the biological and serological characteristics, and RNA3 nucleotide sequence of CMV-I.

Results and conclusions
Over 130 samples were collected and CMV was detected from 8 species including Impatiens balsamina as a newly recorded CMV host in Indonesia mainly by tissue immuno-binding assay. An isolate (CMV-I) was selected and 24 species in 5 families of plants were shown to be infected by CMV-I. Tomato (Ponterosa) showed only faint symptoms and no systemic infection occurred in cucumber cultivars tested (Sagami hanjiro, Ochiai-2). Satellite RNA was not detected from the infected plants. Polyclonal antibodies (As-CMV-I) were prepared by injection to rabbits with purified CMV-I preparations.

The amplified RT-PCR products of CMV-I RNA3 with specific primers for RNA3 of CMV serotype Y were cloned and sequenced. The amino acid sequence of CMV-I coat and 3a proteins were 97 and 96% homologous to those of CMV-Y, respectively.

While information on the biological, serological and sequential diversity of CMV strains/isolates in Asian countries is still limited, comparison of these characters with CMV from other regions will be beneficial for identification and differentiation of the virus strains in and outside Asia.

References
1. Semangun H, 1992. Host index of plant diseases in Indonesia, 351pp.