Detection of Rice Black-Streaked Dwarf Virus In Rice, Maize and Insect Vectors by Enzyme­linked Immunosorbent Assay

효소결합항체법에 의한 벼, 옥수수 및 매개충에서 벼 검은줄 오갈병의 검정

Rice black-streaked dwarf virus(RBSDV) was purified from infected maize leaves. Antiserum against RBSDV was prepared for virus detection by enzyme-linked immunosorbent assay(ELISA). In detection of RBSDV by ELISA, effective dilution range of antiserum extracted in RBSDV-containing host plants and insect vectors was from 320 to 2,560 times in rice plant, 320 to 5,120 in maize plant, and 160 to 2,560 times in insect vector, Laodelphax striatellus F, respectively. The percentage of viruliferous vector in overwintered nymphs of Laodelphax striatellus determined by ELISA were 3.0 in Milyang, 2.3 in Chilgok, and 3.7 in Sunsan area. Dead insect vector which could not be tested for vims infection by conventional rice seedling inoculation test could be tested by ELISA. One hundred plants of rice and maize were randomly sampled in the field and tested whether or not they were infected with RBSDV. In rice plants, 4 out of 98 plants turned out to be infected with RBSDV by ELISA. In maize plant, 3 out of 92 plants which were excepted 8 plants to be appeared symptom already were infected. As a result, ELISA could be detected even in case of symptomless plants at early stage of viral infection.

효소결합항체법에 의한 벼검은줄오갈병 바이러스의 검정에서, 항원의 희석은 벼잎 $320\~2,450$배, 옥수수잎 $320\~5,120$배, 그리고 매개충인 애멸구는 $160\~2,560$배로 하는 것이 효과적이었다. 이상의 검정기준에 따른 성역별 월동약충(애멸구)의 보독충율 조사에서는 밀양 $3.0\%$, 칠곡 $2.3\%$ 그리고 선산은 $3.7\%$였다. 본 방법에 의하면 유묘접종법으로는 불가능한 채집과정에서 죽은 충에서도 바이러스 감염여부를 결정할 수 있었다. 포장에서 임의로 채집한 벼와 옥수수 각 100주씩을 공시하여 그중 외부병징이 없는 98주와 92주를 검정한 결과, 벼에서는 98주중 4주가 이병주로 나타났으며, 옥수수에서는 92주중 3주가 본 방법에 의해 감염된 것으로 나타나 포장에서의 잠복감염율은 벼에서는 $4.11\%$, 옥수수에서는 $3.25\%$로 나타났다. 따라서 효소결합항체법을 사용하면 병징이 잘 나타나지 않는 감염초기에도 검정이 가능하였다.