최근 봄철 기온이 높아짐에 따라 마늘 뿌리응애 피해가 늘어나고 있는 실정이다. 이러한 뿌리응애 피해를 최소하 하고자 발생양상과 22종의 약제에 대하여 살비효과를 조사하였다. 마늘 재배시기 중 뿌리응애의 발생은 충북 보은 등 5지역에서 2015년부터 2017년까지 3년간 3월부터 6월까지 뿌리응애 발생밀도를 조사하여 발생양상을 확인하였다. 뿌리응애는 2016년에 가장 많이 발생하였으며, 발생시기는 월동 후 3월 상순부터 발생하여 6월 중순경까지 지속적으로 밀도가 높아지는 양상을 나타내었다. 조사된 5지역 중 가장 높은 밀도로 조사된 보은지역은 6월 상순경 주당 13.3마리가 발생하였다. 뿌리응애에 대하여 우수한 살비효과를 나타낸 약제는 분무처리시 약제처리 10일 후에서 dimethoate, azocyclotin, abamectin, hexythiazox, cabosulfan, spirotetramat, benfuracarb가 90% 이상의 살비효과를 나타내었다

The bulb mite (BM), Rhizoglyphus echinopus, is hard to control in the harvested onion and garlic. Methyl bromide (MeBr) fumigation is the only option to eradicate BM at present. However, MeBr causes phytotoxic damage (index 3) to onion and garlic and highly toxic to fumigators. To replace MeBr, we evaluated ethyl formate (EF) and phosphine gas (PH3) to BM at 5℃ which is current practical fumigation temperature. The >140 g·h m-3 of EF for 24 h could completely control BM and this CT (concentration × time) product was slightly (index 1) phytotoxic to onion and garlic. Fumigation of 2 g PH3 required >120 h exposure to kill 100% of BM without any pyhtotoxic damage. Further researches are being planned to shorten the exposure time with synergistic effect between EF and PH3.

The bulb mite (Rhizoglyphus echinopus) damages garlic, shallot and onion in the bulbs, corms and tubers. It has recently become a serious problem because of the continuous use of acaricides resulting in resistance among bulb mite population. Thus, there is need to find alternative control measures to suppress bulb mite population. Here, we report the screening result of pathogenic fungi for the control of R. echinopus. Initial screenings were performed using 352 isolates of entomopathogenic fungi from Korea soils. As results, 15 isolates of acaropathogenic fungi showed the pathogenicity to bulb mite supporting fungal conidiation. These isolates were identified as 3 isolates of Metarhizium flavoviride var. pemphigi and 12 isolates of Metarhizium pingshaense by microscopic examination and genetic sequencing of the ITS region and elongation factor-1 alpha. Selected 15 isolates were tested for their virulence against adult R. echinopus and the thermotolerance and the activity to UV-B irradiation of conidia. Additionally, the activities of chitinases and proteases produced by M. pingshaense were compared according to the medium. These acaropathogenic fungi would be considered promising for biological control of bulb mite.