• 한국미생물·생명공학회지
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• 제19권6호
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• pp.614-618
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• 1991

토양세균 B.subtilis subsp. krictiensis로부터 항진균활성물질 KRF-001 복합체를 생산하기 위한 발효 조건을 조사하였다. Whey와 mannitol 등이 탄소원으로, CSL, corn gluten meal 그리고 polypeptone이 복합질소원으로 좋았다. 중온균인 생산균은 중성 pH조건에서 P.oryzae에 대한 bioactivity가 가장 높았으며, 0-10 DO의 낮은 용존산소 조건에서도 bioactivity가 유지되었다. 인산염의 농도가$ K_2HPO_4$, 0.047에서 0.097로 높아짐에 따라 1/2의 bioactivity 감소가 관찰되었다. 한편 UV 및 MNNG에 의한 돌연변이에 의해 우수균주 3개를 선별하였다.

• The Plant Pathology Journal
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• 제36권3호
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• pp.218-230
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• 2020

Net blotch of barley caused by Pyrenophora teres (Died.) Drechsler, is one of the most destructive diseases on barley in Algeria. It occurs in two forms: P. teres f. teres and P. teres f. maculata. A total of 212 isolates, obtained from 58 fields sampled in several barley growing areas, were assessed for fungicide sensitivity by target gene analysis. F129L and G137R mitochondrial cytochrome b substitution associated with quinone outside inhibitors (QoIs) resistance, and succinate dehydrogenase inhibitors (SDHIs) related mutations (B-H277, C-N75S, C-G79R, C-H134R, and C-S135R), were analyzed by pyrosequencing. In vitro sensitivity of 45 isolates, towards six fungicides belonging to three chemical groups (QoI, demethylase inhibitor, and SDHI) was tested by microtiter technique. Additionally, sensitivity towards three fungicides (azoxystrobin, fluxapyroxad, and epoxiconazole) was assessed in planta under glasshouse conditions. All tested isolates were QoI-sensitive and SDHI-sensitive, no mutation that confers resistance was identified. EC₅₀ values showed that pyraclostrobin and azoxystrobin are the most efficient fungicides in vitro, whereas fluxapyroxad displayed the best disease inhibition in planta (81% inhibition at 1/9 of the full dose). The EC₅₀ values recorded for each form of net blotch showed no significant difference in efficiency of QoI treatments and propiconazole on each form. However, in the case of fluxapyroxad, epoxiconazole and tebuconazole treatments, analysis showed significant differences in their efficiency. To our knowledge, this study is the first investigation related to mutations associated to QoI and SDHI fungicide resistance in Algerian P. teres population, as well as it is the first evaluation of the sensitivity of P. teres population towards these six fungicides.