Study on the Effects of Silkworm Diseases on the Cocoon Crops

잠병이 잠작에 미치는 영향에 관한 조사연구

This investigation was conducted to measure the effects of silkworm diseases on the cocoon crepe. The sample farmers were selected at three areas in Korea. a. Banga Ri, Namsa Myoen, Yongin Kun, Kyoenggi Do b. Moorim Ri, Yakmok Myeon, Chilkok Kun, Kyeongsangbuk Do c. Oero Ri, Buksam Myeon, Chilko Kun, Kyeongsangbuk Do 1. Reduction ratio of crops by the silkworm disease was 5.5% in spring season, and 8.9% in the autumn but 7.2% in a year. Including disease damaged cocoons being spoiled cocoons, it was 8.3%. 2. The ratio of disease-damage by the polyhedrosis virus and flacherie was 17.8% of whole disease at young instar and was 82.2% at advanced instar which showed highest ratio. 3. Average production amount of the cocoon was 27.74kg, The reduction amount by the silkworm disease against the estimated production aomunt was 2.411kg. 4. Reduction of amounts by unknown factors was 3.611 kg. This was 1.5 times of reduction amount by the disease. This nay be chiefly due to the missing silkworms and spoiled cocoons. 5. Ratio of farmers harvesting stable cocoon crops was 54.7% in spring rearing season but 21.9% in autumn. 6. Damage ratio of factors other than the silkworm disease was 10.70% and it was 17.87 % of total mortality.

잠병이 잠작에 미치는 영향을 조사하기 위하여 경기도 용인군 남사면 방아리, 경북 칠곡군 약목면 그리고 경북 칠곡군 북삼면의 양잠농가를 대상으로 잠병에 대한 피해율을 조사한 결과는 다음과 같다. 1) 잠병에 의한 감수율은 춘잠기에는 5.5%, 추잠기에는 8.9%이었고 년간 평균 7.2%였으며 하견을 병해견으로 환산한다면 8.3%였다. 2) Virus 다각체병과 연화병에 의한 병해율은 전발병의 치잠기에는 17.8%, 장잠기에는 82.2%로서 높은 비율을 나타내었다. 3) 평균산견량은 상자당 27.74kg이었는데 추정산견량에 대하여 잠병에 의한 감수량은 2.411kg이었다. 4) 원인불명의 감수량이 3.611kg으로서 잠병에 의한 감수량의 약 1.5배였다. 이 원인불명의 감수량은 주로 유실잠과 하견이 많았기 때문이다. 5) 잠작이 비교적 안정된 농가수는 춘기에는 54.7%, 추기에는 21.9%였다. 6) 잠병이외의 피해율은 10.70%였고 전감잠비율은 17.87%였다.