Cultural Characteristics and Ascospore Density in Soil of Monosporascus Cannonballus on Cucurbitaceae Plants

박과류 검은점뿌리썩음병균의 배양적 특성 및 토양내 자낭포자 밀도

The cultural caracteristics of Monosporascus cannonballus causing root rot of Cucurbitaceae plants were examined in vitro, and population density of the fungal ascospores were measured and compared aoming diferent host species and soil depths. Potato-dextrose agar(PDA) was the most appropriate medium for the mycelial growth and perithecial formation among the 5 media tested. Corn-meal agar(CMA), oat-meal agar (OMA) and V-8 juice agar were moderate media for the mycelial growth and perithecial formation, whereas water agar(WA) was poor medium. Perithecia were not formed on WA. Optimum temperature for the formation of perithecia was about 25 to 30$^{\circ}C$. distribution of ascospores in the infested fields was variable amount the curcubitaceae plants and within the same plant species, ranging from 1.7 to 14.6 ascospores in 20 g of soil, but no ascospore was detected in the uninfested field soils. Ascospores were distributed more at 20cm of soil depth than at 10cm or 30cm of soil depth.

최근 박과류 재배 주산단지에서 발생이 증가하고 있는 검은점뿌리썩음병 병원균의 균학적 특성과 발병 포장에서의 병원균 밀도를 조사하였다. Monosporascus cannonballus의 균사생장과 자낭각의 형성은 PDA배지에서 가장 좋았고, CMA와 OMA, V-8 juiceqowl에서는 비슷한 생장량을 보였으나, WA에서는 생장도 빈약하였고 자낭각은 전혀 형성되지 않았다. 자낭각의 형성 적온은 25~3$0^{\circ}C$였다. 이병포장에서 검은점뿌리썩음병균의 자낭포자는 토양 20g당 1.7~14.6개 범위로 존재하였다. 토양심도별로는 10cm나 30cm보다 20cm 깊이에 보다 많이 분포하는 경향이었으나 조사포장간에 편차가 심하였다.