Protective Effect of Iminoctadine tris(albesilate) and Kresoxim-methyl Fungicides to Citrus Postharvest Diseases caused by Penicillium spp.

저장 감귤의 부패에 관여하는 Penicillium spp.에 대한 Iminoctadine tris(albesilate)와 Kresoxym-methyl의 방제 효과

The biological effects of the iminoctadine tris (albesilate) and kresoxim-methyl for the protection of citrus postharvest diseases caused by penicillium spp. were assayed. In vitro tests, $EC_{50}$ values of iminoctadine tris(albesilate) were $0.01{\sim}0.02\;and\;0.01{\mu}g$ a.i./mL against mycelial growth of P. italicum and P. digitatum, respectively, but iminoctadine tris(albesilate) at $0.64{\mu}g$ a.i. /mL inhibited a little mycelial growth of unknown Penicillium sp. which produced another symptom different to blue and green mold caused by P. italicum and P. digitatum, respectively. And against germination and growth of germ tube of P. italicum and P. digitatum, $EC_{50}$ value of iminoctadine tris(albesilate) was $0.0013{\sim}0.0025{\mu}g$ a.i./mL. But spore germination of unknown Penicillium spp. was not nearly inhibited at $0.2{\mu}g$ a.i./mL. $EC_{50}$ values of kresoxim-methyl were $0.08{\sim}0.16$, 0.04 and $0.16{\mu}g$ a.i./mL against mycelial growth of P. italicum, P. digitatum and unknown Penicillium sp., respectively, and $0.04{\sim}0.08{\mu}g$ a.i./mL and $0.01{\sim}0.02{\mu}g$ a.i./mL against germination and growth of germ tube of P. italicum and unknown Penicillium sp., and P. digitatum, respectively. Iminoctadine tris(albesilate) and kresoxim-methyl were markedly effective to control the postharvest disease by 7 days spray prior to harvest. When the fruits were sprayed with iminoctadine-tris(albesilate) ($200{\mu}g$ a.i./mL) and kresoxim-methyl ($155{\mu}g$ a.i./mL) 7 days prior to harvest and subsequently stored for 90 days, the percentage of diseased fruit by Penicillium spp. was $3.6{\pm}1.8%$ in treatment of kresoxim-methyl and $5.9{\pm}1.8%$ in iminoctadine-tris(albesilate), respectively. On the other hand, tile percentage of diseased fruit was relatively high, $20.3{\pm}10.0%\;and\;19.5{\pm}9.6%$ in thiophanate-methyl ($700{\mu}g$ a.i./mL) and non-treatment, respectively. Maximum residue amount (ppm) among fruits (flesh and peel) assayed 0, 30, 60 and 90 days after storage was 0.45 and 0.10 ppm in treatment of kresoxim-methyl and iminoctadine, respectively.

본 연구는 감귤을 부패시키는 Penicillium spp.에 대한 kresoxim-methyl 과 iminoctadine tris(albesilate)의 방제효과를 검정하기 위하여 실시하였다. P. italicum과 P. digitatum의 균사생장에 대한 iminoctadine tris(albesilate)의 $EC_{50}$값은 각각 0.01-0.02와 $0.01{\mu}g$ a.i./mL이었지만, 아직 미동정인 새로운 유형의 Penicillium spp.균은 iminoctadine tris(albesilate)가 $0.64{\mu}g$ a.i./mL들어 있는 PDA배지에서도 거의 균사생장이 억제되지 않았다. 또한 P. italicum과 P. digitatum의 발아와 발아관의 생장에 대한 iminoctadine tris(albesilate)의 $EC_{50}$값은 $0.0013-0.0025{\mu}g$ a.i./mL이었지만 새로운 유형치 Penicillium spp.는 $0.2{\mu}g$ a.i./mL 농도에서도 포자 발아가 거의 억제되지 않았다. P. italicum과 P. digitatum 그리고 미동정 Penicillium spp.의 균사생장에 대한 kresoxim-methyl의 $EC_{50}$은 각각 0.08-0.16, 0.04 그리고 $0.16{\mu}g$ a.i./mL이었으며 P. italicum과 새로운 유형의 Penicillium spp.의 포자 발아 및 발아관 생장에 대한 $EC_{50}$이 $0.04{\sim}0.08{\mu}g$ a.i./mL이며 P. digitatum에 대해서는 $0.01{\sim}0.02{\mu}g$ a.i./mL였다. Kresoxim-methyl과 iminoctadine tris(albesilate)의 저장병에 대한 방제효과를 알아보기 위하여 이들 약제를 각각 $155{\mu}g$ a.i./mL과 $200{\mu}g$ a.i./mL의 농노로 수상살포하고 7일 후 수확하여 90일간 저장한 결과 무처리구와 thiophanate-methyl $700{\mu}g$ a.i./mL을 처리한 대조구에서의 부패율은 각각 $20.3{\pm}10.0%\;and\;19.5{\pm}9.6%$으로 높은데 반하여 tresoxim-methyl과 imonoctadine tris(albesilate) 처리구에서의 부패율은 각각 $3.6{\pm}1.8%$ 과 $5.9{\pm}1.8%$로써 방제효과가 높았다. 이들 처리로부터 저장 후 0, 30, 60, 90일에 각각 iminoctadine tris(albesilate)와 kresoxim-methyl의 잔류량을 조사해본 결과 각 조사 기간 중 iminoctadine tris(albesilate)의 최대잔류량은 0.10 ppm이었고 kresoxlm-methyl의 최대 잔류량은 0.45 ppm이었다.