[ Objective] The study was aimed to determine the biological characteristics of Rhabditis （Oscheius） sp. isolated from a rhizosphere soil of alfalfa field in Hailar City, Hulunbuir League, Inner Mongolia Autonomous ...[ Objective] The study was aimed to determine the biological characteristics of Rhabditis （Oscheius） sp. isolated from a rhizosphere soil of alfalfa field in Hailar City, Hulunbuir League, Inner Mongolia Autonomous Region. [ Method] The last instar larvae of Galleria mellonella and Tenebrio molitor were used as insect hosts. The infectivity of nematode was determined, and its heat tolerance ability was measured by using water bath method. [Result] The infectivity of the nematodes was lower at the dosages of 10, 20 and 40 IJs/larva, but higher at the dosages of 80,160, 32.0 and 640 IJs/larva. The corrected mortality （CM） of G. mellonella at 96 h and T. molitor at 120 h were both above 90%. The nematode infectivity was highest at the dosage of 80 IJs/larva when the hosts＇ CM reached 100% after 120 h. About 25% nematode individuals could survive in 36℃ water bath for 2 d in the densities of 1 000 -5 000 IJ/ml, after 6 d, there were still 3% -9% individuals survived, until 9 d the nematodes died totally. A hundred percent of the nematode individuals died in 38℃ and 40 ~C water bath after 6 h and 2 h, respectively. [Conclusion] Rhabditis （ O. ） sp. has a higher potential to cause the host mortality and represents heat tolerance up to 36℃.展开更多
Rhabditis sp.Bn strain was the first time found suppressive on plant parasitic nematodes(PPNs)in the rhizosphere of greenhouse cucumber.The nematode Bn was applied into soil at the rate of 1.0×1010 Juveniles/hm2 ...Rhabditis sp.Bn strain was the first time found suppressive on plant parasitic nematodes(PPNs)in the rhizosphere of greenhouse cucumber.The nematode Bn was applied into soil at the rate of 1.0×1010 Juveniles/hm2 10 days before cucumber plants being planted in October 2004 and then once a month as treatment.The same volume of tap water was used as control.The density of PPNs increased sharply in control and reached 1 561 Js/100 mL soil in April,whereas it was less than 400 Js/100 mL soil in treatment,significantly lower than that of control(P<0.01).The densities of PPNs,Meloidogyne spp.and Tylenchorhynchus spp.were reduced by 70% and 87% respectively by applying Rhabditis sp.Bn strain.The root-knot index of cucumber in treatment was also reduced significantly(P<0.05)in April 2005.展开更多
2010—2013年在昆虫病原线虫调查中,从华南农业大学植物园采集土样,利用大蜡螟（Galleria mellonella）诱集,获得1个小杆类昆虫病原线虫种群（华农种群HN）。该线虫雌虫的形态符合Oscheius myriophila的原始描述,测量值中除虫体宽度（70...2010—2013年在昆虫病原线虫调查中,从华南农业大学植物园采集土样,利用大蜡螟（Galleria mellonella）诱集,获得1个小杆类昆虫病原线虫种群（华农种群HN）。该线虫雌虫的形态符合Oscheius myriophila的原始描述,测量值中除虫体宽度（70~123 vs 57~70 μm）和口腔宽度（5~8 vs 〈4.5 μm）更宽、尾更长（138~188 vs 108~135 μm）外,其余特征值均在该种原始描述的范围内;用HN种群的18S和28S r DNA序列进行Blast搜寻和比对,结果表明该种群18S序列与GenBank中的O.myriophila（AY602176）的相似度高达99%（1512/1514=99%）,28S序列与O.myriophila（U81588）的相似度达100%（609/609=100%）。分子系统发育分析结果显示,HN与Gen Bank中的多个O.myriophila种群以高置信度聚在相同的Insectivorus 支系。综合形态学和18S和28S rDNA序列特征,确定华农种群HN为Oscheius myriophila。展开更多
基金Supported by Ministry of Science and Technology of China on 863 Program"Soil Technique of Nematode Repair Biological Pollution"(2006AA06Z354)Support Plan Program"Production Technology ofHigh Efficiency Standard on Main Fruit Trees"(2008BAD92B08)BeijingGovernment on Purchasing Technology Service Program(2007DAg03B03-07)~~
文摘[ Objective] The study was aimed to determine the biological characteristics of Rhabditis （Oscheius） sp. isolated from a rhizosphere soil of alfalfa field in Hailar City, Hulunbuir League, Inner Mongolia Autonomous Region. [ Method] The last instar larvae of Galleria mellonella and Tenebrio molitor were used as insect hosts. The infectivity of nematode was determined, and its heat tolerance ability was measured by using water bath method. [Result] The infectivity of the nematodes was lower at the dosages of 10, 20 and 40 IJs/larva, but higher at the dosages of 80,160, 32.0 and 640 IJs/larva. The corrected mortality （CM） of G. mellonella at 96 h and T. molitor at 120 h were both above 90%. The nematode infectivity was highest at the dosage of 80 IJs/larva when the hosts＇ CM reached 100% after 120 h. About 25% nematode individuals could survive in 36℃ water bath for 2 d in the densities of 1 000 -5 000 IJ/ml, after 6 d, there were still 3% -9% individuals survived, until 9 d the nematodes died totally. A hundred percent of the nematode individuals died in 38℃ and 40 ~C water bath after 6 h and 2 h, respectively. [Conclusion] Rhabditis （ O. ） sp. has a higher potential to cause the host mortality and represents heat tolerance up to 36℃.
文摘Rhabditis sp.Bn strain was the first time found suppressive on plant parasitic nematodes(PPNs)in the rhizosphere of greenhouse cucumber.The nematode Bn was applied into soil at the rate of 1.0×1010 Juveniles/hm2 10 days before cucumber plants being planted in October 2004 and then once a month as treatment.The same volume of tap water was used as control.The density of PPNs increased sharply in control and reached 1 561 Js/100 mL soil in April,whereas it was less than 400 Js/100 mL soil in treatment,significantly lower than that of control(P<0.01).The densities of PPNs,Meloidogyne spp.and Tylenchorhynchus spp.were reduced by 70% and 87% respectively by applying Rhabditis sp.Bn strain.The root-knot index of cucumber in treatment was also reduced significantly(P<0.05)in April 2005.
文摘2010—2013年在昆虫病原线虫调查中,从华南农业大学植物园采集土样,利用大蜡螟（Galleria mellonella）诱集,获得1个小杆类昆虫病原线虫种群（华农种群HN）。该线虫雌虫的形态符合Oscheius myriophila的原始描述,测量值中除虫体宽度（70~123 vs 57~70 μm）和口腔宽度（5~8 vs 〈4.5 μm）更宽、尾更长（138~188 vs 108~135 μm）外,其余特征值均在该种原始描述的范围内;用HN种群的18S和28S r DNA序列进行Blast搜寻和比对,结果表明该种群18S序列与GenBank中的O.myriophila（AY602176）的相似度高达99%（1512/1514=99%）,28S序列与O.myriophila（U81588）的相似度达100%（609/609=100%）。分子系统发育分析结果显示,HN与Gen Bank中的多个O.myriophila种群以高置信度聚在相同的Insectivorus 支系。综合形态学和18S和28S rDNA序列特征,确定华农种群HN为Oscheius myriophila。
