Semi-selective media are valuable tools for detection and isolation of viable fungal propagules. After testing the in vitro sensitivity of Pochonia chlamydosporia to 9 different fungicidal compounds, boscalid and thio...Semi-selective media are valuable tools for detection and isolation of viable fungal propagules. After testing the in vitro sensitivity of Pochonia chlamydosporia to 9 different fungicidal compounds, boscalid and thiophanate-methyl were chosen for a modification of Kerry’s semi-selective agar. Rifampicin replaced tetracyclin to provide superior suppression of bacterial growth. The Pc medium contained 17 g/L corn meal agar, 17.5 g/L (NaCl), 75 mg/L Rose Bengal, 50 mg/L boscalid, 30 mg/L thiophanate-methyl, 50 mg/L rifampicin, 50 mg/L streptomycin sulphate, 50 mg/L chloramphenicol, 3 mL/L Triton X-100. Dilution plating of soil extracts from various California field soils amended with chlamydospores of P. chlamydosporia showed the modified medium was equivalent to Kerry’s agar in enumerating viable propagules of the fungus. While P. chlamydosporia colonies grew slower on the Pc medium, the fungal colonies appeared more uniform than on the original semi-selective agar.展开更多
Root-knot nematodes （Meloidogvne spp.） constrain the production of high value vegetable crops, such as tomato, on smallholder farms in Kenya. For several years, control of root-knot nematodes largely depended on the...Root-knot nematodes （Meloidogvne spp.） constrain the production of high value vegetable crops, such as tomato, on smallholder farms in Kenya. For several years, control of root-knot nematodes largely depended on the use of synthetic nematicides, most of which have been banned due to their toxicity to humans and the environment. Farmer-participatory trials were established, for two consecutive growing seasons on farmers＇ fields infested with root-knot nematodes （A4eloidogvne javanica and Meloidogyne incognita）, at two sites in central Kenya （Maragua and Kirinyaga districts）, representing two contrasting group of farmers （low-input and high-input）. The trials aimed at evaluating the potential of using biological control agents （BCAs）, i.e. Poehonia ehlamydosporia and Pasteuria penetrans, antagonistic plants （Crotalaria grahamiana and Tagetes minuta）, ＂＇trash burning＂ and chemical control （dazomet 98% = Basamid~ Granular） in the management of root-knot nematodes in tomato nursery beds, and quantify the associated net benefits, compared to an untreated control. Crotalaria grahamiana, ＂trash burning＂ and dazomet, significantly （P 〈 0.05） reduced the number of second-stage juveniles （J2s） of the root-knot nematodes in the soil in nursery beds during the first season at Karigui-ini, but there was no significant （P 〉 0.05） increase in yield after transplanting tomato seedlings from the respective treatment. Similarly, one of the BCAs （P. ehlamydosporia）, was effectively transferred to the field with seedlings from the BCA-treated nursery beds, but there was no significant （P 〉 0.05） increase in yield due to slow proliferation of the BCA, after transplanting. Participatory partial budgets were successfully developed with srnallholder farmers, and proved to be a vital tool in making informed decisions on management options for root-knot nematodes. In general, labour was considered by all farmers as the major input that contributed to the overall additional cost of the different treatments at both sites. This necessitates improvement in efficiency of labour resource use.展开更多
为探讨不同培养基对厚垣普可尼亚菌胞外蛋白质的诱导效果及相应发酵液的生化性质,以更好地利用该菌对家畜寄生性线虫进行生物防治,在本实验室前期研究的基础上,设计使用3种常用真菌液体培养基对厚垣普可尼亚菌进行发酵培养,并检测发酵...为探讨不同培养基对厚垣普可尼亚菌胞外蛋白质的诱导效果及相应发酵液的生化性质,以更好地利用该菌对家畜寄生性线虫进行生物防治,在本实验室前期研究的基础上,设计使用3种常用真菌液体培养基对厚垣普可尼亚菌进行发酵培养,并检测发酵液的蛋白质质量浓度、蛋白酶活性,磷酸酶活性及杀虫效力等,筛选出适合该菌液体培养的最佳培养基。结果表明,在3组培养基中,LMZ培养基组的蛋白质种类最丰富,蛋白质质量浓度（2 320 mg/L±10.00 mg/L）、蛋白酶活性（2.95 U/m L±0.23 U/m L）与磷酸酶活性[1.546 U/100 m L±0.035 U/100 m L（酸性磷酸酶）和0.516 U/100 m L±0.069 U/100 m L（碱性磷酸酶）]都较高,对线虫的杀虫率也是3种培养基中最高的,可达60%,与其他各组间差异极显著（P〈0.01）。因此从生物防治的角度,在试验的3种培养基中,以LMZ液体培养基为最佳选择。这一发现可为今后对厚垣普可尼亚菌液体发酵培养、杀虫物质的产生以及作用机制进行深入探究提供重要基础资料。展开更多
文摘Semi-selective media are valuable tools for detection and isolation of viable fungal propagules. After testing the in vitro sensitivity of Pochonia chlamydosporia to 9 different fungicidal compounds, boscalid and thiophanate-methyl were chosen for a modification of Kerry’s semi-selective agar. Rifampicin replaced tetracyclin to provide superior suppression of bacterial growth. The Pc medium contained 17 g/L corn meal agar, 17.5 g/L (NaCl), 75 mg/L Rose Bengal, 50 mg/L boscalid, 30 mg/L thiophanate-methyl, 50 mg/L rifampicin, 50 mg/L streptomycin sulphate, 50 mg/L chloramphenicol, 3 mL/L Triton X-100. Dilution plating of soil extracts from various California field soils amended with chlamydospores of P. chlamydosporia showed the modified medium was equivalent to Kerry’s agar in enumerating viable propagules of the fungus. While P. chlamydosporia colonies grew slower on the Pc medium, the fungal colonies appeared more uniform than on the original semi-selective agar.
文摘Root-knot nematodes （Meloidogvne spp.） constrain the production of high value vegetable crops, such as tomato, on smallholder farms in Kenya. For several years, control of root-knot nematodes largely depended on the use of synthetic nematicides, most of which have been banned due to their toxicity to humans and the environment. Farmer-participatory trials were established, for two consecutive growing seasons on farmers＇ fields infested with root-knot nematodes （A4eloidogvne javanica and Meloidogyne incognita）, at two sites in central Kenya （Maragua and Kirinyaga districts）, representing two contrasting group of farmers （low-input and high-input）. The trials aimed at evaluating the potential of using biological control agents （BCAs）, i.e. Poehonia ehlamydosporia and Pasteuria penetrans, antagonistic plants （Crotalaria grahamiana and Tagetes minuta）, ＂＇trash burning＂ and chemical control （dazomet 98% = Basamid~ Granular） in the management of root-knot nematodes in tomato nursery beds, and quantify the associated net benefits, compared to an untreated control. Crotalaria grahamiana, ＂trash burning＂ and dazomet, significantly （P 〈 0.05） reduced the number of second-stage juveniles （J2s） of the root-knot nematodes in the soil in nursery beds during the first season at Karigui-ini, but there was no significant （P 〉 0.05） increase in yield after transplanting tomato seedlings from the respective treatment. Similarly, one of the BCAs （P. ehlamydosporia）, was effectively transferred to the field with seedlings from the BCA-treated nursery beds, but there was no significant （P 〉 0.05） increase in yield due to slow proliferation of the BCA, after transplanting. Participatory partial budgets were successfully developed with srnallholder farmers, and proved to be a vital tool in making informed decisions on management options for root-knot nematodes. In general, labour was considered by all farmers as the major input that contributed to the overall additional cost of the different treatments at both sites. This necessitates improvement in efficiency of labour resource use.
文摘为探讨不同培养基对厚垣普可尼亚菌胞外蛋白质的诱导效果及相应发酵液的生化性质,以更好地利用该菌对家畜寄生性线虫进行生物防治,在本实验室前期研究的基础上,设计使用3种常用真菌液体培养基对厚垣普可尼亚菌进行发酵培养,并检测发酵液的蛋白质质量浓度、蛋白酶活性,磷酸酶活性及杀虫效力等,筛选出适合该菌液体培养的最佳培养基。结果表明,在3组培养基中,LMZ培养基组的蛋白质种类最丰富,蛋白质质量浓度（2 320 mg/L±10.00 mg/L）、蛋白酶活性（2.95 U/m L±0.23 U/m L）与磷酸酶活性[1.546 U/100 m L±0.035 U/100 m L（酸性磷酸酶）和0.516 U/100 m L±0.069 U/100 m L（碱性磷酸酶）]都较高,对线虫的杀虫率也是3种培养基中最高的,可达60%,与其他各组间差异极显著（P〈0.01）。因此从生物防治的角度,在试验的3种培养基中,以LMZ液体培养基为最佳选择。这一发现可为今后对厚垣普可尼亚菌液体发酵培养、杀虫物质的产生以及作用机制进行深入探究提供重要基础资料。
