瑞香狼毒根乙醇提取物及4种溶剂萃取物对两种叶螨及豌豆蚜的触杀活性比较

本文分别采用玻片浸渍法和带虫浸叶法测定比较了瑞香狼毒根乙醇提取物及4种不同溶剂萃取物对截形叶螨、二斑叶螨及豌豆蚜的触杀活性。结果表明,瑞香狼毒根的乙醇提取物对截形叶螨、二斑叶螨、豌豆蚜处理12h的校正死亡率分别为60.28%、59.24%、54.32%,24h的校正死亡率分别为66.75%、61.45%、65.53%;石油醚萃取物对3种供试生物处理12h和24h校正死亡率分别为89.39%、93.70%、91.49%和93.33%、84.19%、100%;氯仿萃取物处理12h和24h后校正死亡率分别为32.11%、35.66%、27.35%和34.47%、35.95%、38.60%,瑞香狼毒4种溶剂萃取物触杀活性顺序为:石油醚氯仿水乙酸乙酯,随着浓度增大,萃取物对3种供试生物的触杀活性明显增强,表现出良好的量效关系。石油醚萃取物对截形叶螨12h和24h的LC50分别为2.040 2mg/mL和0.8mg/mL;对二斑叶螨12h和24h的LC50分别为0.280 3mg/mL和0.037mg/mL;对豌豆蚜12h和24h的LC50分别为0.911 4mg/mL和0.360 5mg/mL,24h毒力均高于12h毒力。     

36种中草药提取物杀松材线虫活性研究

为了从中草药中寻找高效杀线虫活性物质,本文测定了36种中草药提取物对松材线虫及其卵的毒杀活性。结果表明,牡丹皮、黄连和大黄3种中药的乙醇提取物杀线虫活性较强,以提取物浓度为10 g/L处理松材线虫72 h后,校正死亡率均为100%。3种中药提取物处理松材线虫72 h后半致死浓度（LC50）分别为1.81、0.2638和1.07 g/L。杀卵活性结果表明,3种中药提取物处理72 h后,线虫卵的孵化率均低于20%,虫卵的校正死亡率均高于60%。利用乙酸乙酯和水作溶剂对3种中草药进行初步的杀线活性成分分离的结果表明,牡丹皮的杀线活性物质存在于乙酸乙酯萃取物中,黄连和大黄的杀线活性物质存在于水萃取物中。3种中药的不同萃取物处理松材线虫72 h后的LC50分别为0.712、2.370和0.067 g/L。     

几种真菌对马铃薯腐烂茎线虫趋化性的影响及其引诱物质的初步分析

马铃薯腐烂茎线虫Ditylenchus destructor Thorne是我国重要的检疫性病原线虫。为筛选对该线虫具有高效引诱活性的物质,本研究利用水琼脂平板法测试了不同真菌及其培养滤液对马铃薯腐烂茎线虫的引诱作用。结果表明,线虫对不同测试真菌趋性不同,其中对灰葡萄孢的趋性最强。在处理36 h后灰葡萄孢菌饼对线虫诱集率达到15%,其培养滤液对线虫的诱集率为8%,显著高于相应的禾谷镰刀菌、半裸镰刀菌处理与对照。灰葡萄孢对线虫的引诱作用随着处理时间延长而增加,处理96 h后灰葡萄孢菌片诱集到的线虫数为78头,引诱率为26%。经80℃加热120 min后灰葡萄孢菌饼对线虫的引诱能力未显著降低,说明灰葡萄孢中对线虫具诱引活性的物质对热稳定。灰葡萄孢正丁醇和乙醇提取物对线虫诱集率分别为11.6%和11.0%,显著高于石油醚提取物和甲醇对照。本研究可为开发马铃薯腐烂茎线虫防治新策略奠定基础。     

甘薯对马铃薯腐烂茎线虫趋化性的影响

由马铃薯腐烂茎线虫侵染造成的甘薯茎线虫病是一种严重影响甘薯产量和品质的病害。线虫向寄主根部移动及取食危害可能是受寄主释放的化感信息物质控制。为最终明确甘薯中对线虫具有高效引诱能力的物质,本研究利用水琼脂平板法测试了甘薯不同品种与不同组织对线虫的引诱作用。结果表明不同品种甘薯薯块和薯茎对马铃薯腐烂茎线虫引诱能力具有一定差异,感线虫品种栗子香的薯块对线虫的引诱率要高于其他测试品种。随着薯块/薯茎在水琼脂平板上放置时间延长,其吸引线虫的效果增加,96 h后引诱率达到20%。同一品种甘薯茎的引诱能力显著高于薯块、薯叶。甘薯中所含对线虫具引诱作用的活性物质对热稳定,80℃加热8 h后薯茎对线虫引诱率与新鲜茎相比无显著差异,为4.5%。甘薯茎经过不同有机溶剂分别萃取后,乙醇萃取物对线虫的引诱率为6.7%,显著高于其他萃取物。本文初步明确了甘薯中所含线虫趋化物的性质,为其开发应用奠定了基础。     

烤烟‘K326’抗TMV防御物质初探

烤烟主栽品种‘K326’在打顶后,随着次生代谢产物的积累,烟草花叶病症状呈减轻趋势。本试验利用半叶枯斑法对‘K326’的全株、根、茎、叶甲醇提取物及根部不同极性溶剂萃取物进行抗烟草普通花叶病毒活性筛选,结果表明:在浓度为1mg/mL时,‘K326’各部位甲醇提取物中,根部甲醇提取物的活性最强,对TMV体外钝化、初侵染和复制增殖作用的抑制率分别为74.50%、68.82%和47.76%;利用不同极性溶剂对根部甲醇提取物萃取处理后,乙酸乙酯萃取物活性增强明显,对TMV体外钝化、初侵染和复制增殖作用的抑制率分别为76.81%、78.02%、61.42%;经普通烟‘K326’进一步验证,根部甲醇提取物的乙酸乙酯萃取物活性最强。综上,‘K326’中抗病毒防御物质可能存在于根部甲醇提取物的乙酸乙酯萃取物中。     

几种化学药剂和微生物菌剂对腐烂茎线虫的室内触杀活性

本研究比较了5种化学药剂和4种微生物菌剂对腐烂茎线虫的室内触杀活性,并在此基础上进一步探究了化学药剂与微生物菌剂复合使用的效果。结果表明,在5种供试化学药剂推荐浓度条件下,70%噁霉灵可湿性粉剂26.92 g/L对腐烂茎线虫的触杀效果最好,72 h的校正死亡率可达87.32%,20%噻唑膦水乳剂6.06 g/L与41.70%氟吡菌酰胺悬浮剂5.21 g/L对腐烂茎线虫的触杀活性次之;用以上3种化学药剂100倍稀释液处理腐烂茎线虫,72 h后20%噻唑膦水乳剂2.00 g/L与70%噁霉灵可湿性粉剂7.00 g/L的效果最好,腐烂茎线虫的校正死亡率分别为84.61%和81.68%。在供试的4种微生物菌剂中,推荐用量条件下,有效活菌数≥200.0亿/g抗根结线虫菌剂粉剂500 g/L对腐烂茎线虫的触杀效果最好,72 h的校正死亡率达76.48%,其次为10亿活芽胞/g枯草芽胞杆菌可湿性粉剂66.6 g/L。有效活菌数≥200.0亿/g抗根结线虫菌剂粉剂在推荐用量基础上增加25%用量可提高对腐烂茎线虫的触杀效果,72 h校正死亡率达到85.58%。同时,化学药剂与微生物菌剂在一定浓度条件下复合使用可以显著提高对腐烂茎线虫的触杀效果,其中有效活菌数≥200.0亿/g抗根结线虫菌剂粉剂与70%噁霉灵可湿性粉剂复合处理的效果最好,腐烂茎线虫在48 h的校正死亡率达到93.30%;其次为有效活菌数≥200.0亿/g抗根结线虫菌剂粉剂与20%噻唑膦水乳剂的组合,48 h的校正死亡率达到81.68%。本研究为腐烂茎线虫的有效防控提供了新的思路和方法。     

10种植物提取物对南方根结线虫毒杀活性研究

采用触杀法研究了10种植物干材料无水乙醇提取物、乙酸乙酯提取物和石油醚提取物对南方根结线虫2龄幼虫的毒杀活性。结果表明,这10种植物材料的3种有机溶剂提取物对根结线虫都有不同程度的毒杀活性。其中,牡丹皮、丁香、八角茴香、何首乌和地肤子的无水乙醇和乙酸乙酯提取物的毒杀活性最强,48 h校正死亡率均大于90%;八角茴香石油醚提取物也表现出较高毒杀活性,48 h校正死亡率也达到了80%以上。     

溴氰菊酯对马铃薯腐烂茎线虫的毒力及对其运动和摄食的影响

采用药液浸渍法、沙柱法以及与荧光染料Cy3共孵育的方法,以丙溴磷、克百威和阿维菌素为对照药剂,测定了溴氰菊酯对马铃薯腐烂茎线虫Ditylenchus destructor的毒力以及对其运动扩散和摄食的影响。结果表明:溴氰菊酯对马铃薯腐烂茎线虫具有一定的杀灭活性,其LC50值为459.8mg/L,活性低于丙溴磷(159.9mg/L)、克百威(331.9mg/L)和阿维菌素(257.3mg/L);溴氰菊酯对马铃薯腐烂茎线虫运动扩散的抑制作用IC50值为3.1mg/L,其活性低于阿维菌素(0.8mg/L),但高于丙溴磷(8.3mg/L)和克百威(16.1mg/L)。当丙溴磷和克百威质量浓度分别低至0.6和40mg/L时,可刺激90%以上的线虫摄食;当丙溴磷和克百威质量浓度最低分别为360和300mg/L时,可抑制全部线虫的摄食;溴氰菊酯与阿维菌素则对线虫的摄食无刺激作用;用10mg/L的丙溴磷处理线虫2h后再分别用阿维菌素和溴氰菊酯处理,发现阿维菌素和溴氰菊酯质量浓度最低分别为20和200mg/L时可抑制全部马铃薯腐烂茎线虫的摄食。研究表明,溴氰菊酯对马铃薯腐烂茎线虫具有较高的活性,其在线虫防治领域的开发应用潜力较好。     

苦瓜叶提取物对黄曲条跳甲成虫的拒食作用

本文研究了苦瓜Momordica charantia叶片提取物对黄曲条跳甲Phyllotreta striolata成虫的拒食活性,结果表明,用4000μg/ml苦瓜叶片乙醇提取物对黄曲条跳甲成虫的取食有明显的抑制作用。用石油醚、乙酸乙酯、正丁醇和水依次对苦瓜叶片乙醇提取物进行萃取,在4种萃取物中,乙酸乙酯萃取物对黄曲条跳甲成虫的拒食作用最强。用2000μg/ml和4000μg/ml的苦瓜叶乙酸乙酯萃取物处理甘蓝叶片48h后,在选择性试验中对黄曲条跳甲成虫的拒食率分别为41.42%和66.27%;在非选择性试验中的拒食率分别为30.90%和59.62%。     

瑞香狼毒活性物质对草莓灰霉病菌的抑制作用

 为探索瑞香狼毒（Stellera chamaejasme）提取物对草莓灰霉病菌（Botrytis cinerea）的抑菌活性,采用生物活性跟踪法对瑞香狼毒的抑菌活性成分进行初步研究,柱层析法对其甲醇萃取物高活性成分进行分离,经LC-MS和核磁共振仪对最终成分进行结构鉴定,结果表明瑞香狼毒最高活性流份3的主要抑菌活性成分为伞形花内酯,并且随着浓度的提高,该活性成分对草莓灰霉病菌的抑制作用也增强,其抑菌中浓度为1.52 mg·mL^-1。通过扫描电镜观察流份3对草莓灰霉病菌超微结构的影响,结果发现伞形花内酯严重破坏了草莓灰霉病菌孢子和菌丝体的形态结构。     

苍耳杀线虫活性的初步研究

通过温室盆栽试验研究了苍耳叶5种溶剂提取物对番茄根结线虫(Meloidogyneincognita)的活性。结果表明,苍耳叶5种溶剂提取物均有一定的杀线虫活性,其中丙酮与甲醇提取物120mg干粉/mL的防治效果最佳,分别为75.54%和73.83%。不同溶剂对苍耳叶的提取率间存在明显差异,且这种差异与不同溶剂提取物杀线虫活性间的差异之间存在一定相关性。同时苍耳叶提取物对番茄生长具有一定的抑制作用。     

枯草芽孢杆菌挥发产物的杀线虫活性评价及成分鉴定

寄牛线虫Ditylenchus destructor是许多作物和蔬菜的重要病原物.本研究进行的密封皿内测定结果表明,由枯草芽孢杆菌BL02和G8产生的挥发物能够强烈地抑制D.destructor(24 h杀虫活件均达100%).经挥发物处理后,大部分线虫在1～12 h内活动逐渐减弱,24 h后完全停止活动.经固相微萃取并经气相色谱-质谱联脂技术进一步鉴定,挥发物包括烷烃、醇、酯、酮、酸、胺、肟、酚及杂环类.本研究为微生物活性挥发物的开发和利用提供了有价值的参考并预示了细菌挥发物在未来植物线虫病害生物防治方而的应用潜力.     

Screening and isolation of a nematicidal sesquiterpene from Magnolia grandiflora L

The ethanolic extracts from 30 plant species were tested for their nematicidal activity against nematodes Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle and Panagrellus redivivus (L.) Goodey. The leaf extract of Magnolia grandiflora L. exhibited the strongest nematicidal activity against both nematodes, causing 73 and 100% mortality respectively within 48 h at 5 mg mL(-1). A new nematicidal sesquiterpene was obtained from the leaves of M. grandiflora. The compound was determined to be 4,5-epoxy-1(10)E,11(13)-germacradien-12,6-olide, based on spectroscopic methods including 2D NMR techniques. The median lethal concentrations (LC50) of the compound against B. xylophilus and P. redivivus were 71 and 46 mg L(-1) respectively at 48 h. This is the first report of Magnoliaceae species with nematicidal activity.     

Nematicidal activity of the leaf powder and extracts of Myrtus communis against the root‐knot nematode Meloidogyne javanica

Nematicidal activity of the leaf powder, leaf extracts and formulated leaf extracts of Myrtus communis, an evergreen shrub that is widely distributed in Israel and other Mediterranean countries, was evaluated using the root‐knot nematode Meloidogyne javanica in in vitro and pot experiments. Leaf powder added to sand at 0·1% (w/w) reduced the number of juveniles recovered from the sand by more than 50%. Reduction in galling index and number of nematode eggs on tomato roots was also observed by incorporating the leaf powder at 0·1–0·4% (w/w) in the soil in pot experiments. Leaf powder extracts with methanol or ethanol showed the highest nematicidal activity among all extracts tested. Emulsifiable concentrates of leaf‐paste extract at a concentration as low as 0·005% (a.i., w/w) reduced the number of juveniles recovered from treated sand and the gall index of cucumber seedlings. The extract paste at 26 g m^?2 was also effective in reducing the gall index of tomato plants in field‐plot experiments. The leaf powder at 0·2% and the formulated leaf‐paste extract at 0·02% were also nematicidal to Tylenchulus semipenetrans and Ditylenchus dipsaci, but not to Pratylenchus penetrans or Steinernema feltiae. At least three nematicidal compounds were found in the leaf extract upon fractionation by thin‐layer chromatography. The results suggest that the leaf powder and paste extract of M. communis are potential nematicides against root‐knot nematodes.     

Nematicidal activity of Ochradenus baccatus against the root‐knot nematode Meloidogyne javanica

Ochradenus baccatus is a widely distributed shrub in desert regions of the Middle East and North Africa. This plant's nematicidal activity against the root‐knot nematode Meloidogyne javanica was evaluated because it has been found to contain exceptionally high levels of glucosinolates. In in vitro assays with aqueous extracts of the plant, 100% of second‐stage juveniles were immobilized after exposure to 4% root‐core extract for 48 h; 8% root‐core extract suppressed their hatching by 87%, whereas stem, flower and root bark showed lower activity. Incorporation of root core or bark into the soil, as fresh or dry powder at 1 and 0·5% (w/w), respectively, reduced the number of nematodes recovered from the soil by 95–100%, whereas the flower and stem were much less effective. Results from further pot experiments indicated that only the root bark consistently contains nematicidal compounds which are effective in soil, whereas the nematicidal activity of the root core in soil was inconsistent. The presence of non‐volatile lipophilic and lipophobic nematicidal compounds in the root bark was suggested by extraction with different polar solvents, but these compounds do not seem to be isothiocyanates – glucosinolate‐hydrolysed compounds with nematicidal activity. Very poor host status of Ochradenus baccatus to M. javanica, M. incognita and M. hapla, but with root‐penetration rates of juveniles similar to those in tomato roots, suggest that this plant may be used as a cover plant or trap plant to reduce nematode populations in the soil.     

两种葱属植物提取液对香蕉枯萎病菌的毒力测定及GC-MS分析

 以韭菜和葱的乙酸乙酯提取液对香蕉枯萎病菌进行了抑菌试验,并在高温条件下,采用气相色谱-质谱法(GC-MS)对葱的各部位、韭菜根的乙酸乙酯提取液进行分析。结果表明:韭菜和葱各部位乙酸乙酯提取液对香蕉枯萎病菌均有一定的抑制作用,以韭菜茎的抑制效果最好,为29.85%,韭菜根的抑制效果次之;葱的根、茎、叶和韭菜根的乙酸乙酯提取液检出物分别为34、20、12和21种,其中韭菜根提取液中有较多的含硫化合物,脒基硫脲最多,为17.01%。葱提取液中除含硫化合物外,还检出噻吩、吡嗪和喹啉类物质。     

Velvetbean (Mucuna pruriens) extracts: impact on Meloidogyne incognita survival and on Lycopersicon esculentum and Lactuca sativa germination and growth

Velvetbean (Mucuna spp.) is a summer annual that has been used as a cover crop to reduce erosion, fix nitrogen and suppress weeds and plant-parasitic nematodes. Crude aqueous extracts (1:15 dry weight plant/volume water) were made from velvetbean plant parts, and various concentrations of the extracts were evaluated in vitro for toxicities to different stages of Meloidogyne incognita (Kofoid and White) Chitwood and for suppression of hypocotyl and root growth and inhibition of germination of tomato (Lycopersicon esculentum L.) and lettuce (Lactuca sativa L.). Germination was only affected by the full-strength extract from leaf blades. Lettuce root growth was the most sensitive indicator of allelopathic activity of the plant part extracts. Lettuce and tomato root growth was more sensitive to the extract from main roots than to extracts of other plant parts, with lethal concentration (LC50) values of 1.2 and 1.1% respectively. Meloidogyne incognita egg hatch was less sensitive to extracts from velvetbean than the juvenile (J2) stage. There was no difference among LC50 values of the extracts from different plant parts against the egg stage. Based on LC50 values, the extract from fine roots was the least toxic to J2 (LC50 39.9%), and the extract from vines the most toxic (LC50 7.8%). The effects of the extracts were nematicidal because LC50 values did not change when the extracts were removed and replaced with water.     

和田鞘氨醇杆菌AMCC 100218菌株的筛选、鉴定及杀线虫特性

为筛选对南方根结线虫具有致死效果的生防细菌,从山东省10个县市蔬菜主产区番茄根际土壤中分离可培养细菌,采用离体杀线虫试验测定分离菌株对南方根结线虫Meloidogyne incognita的致死活性,结合生理生化特征及分子生物学方法对高效杀线虫菌株进行分类鉴定,同时对其杀线虫特性进行表征,并通过盆栽试验进一步验证其生防潜力。结果显示,从山东省蔬菜主产区番茄根际土中分离到1株高效杀线虫菌株AMCC 100218,结合生理生化试验与16S rRNA序列分析,鉴定此菌株为和田鞘氨醇杆菌Sphingobacterium hotanense;该菌株对南方根结线虫2龄幼虫的致死效果可达88.87%,其杀线虫活性物质具有较好的热稳定性和储存稳定性,且耐碱不耐酸;盆栽试验结果表明,该菌能够显著减少土壤中的虫口密度,降低番茄发病率。表明和田鞘氨醇杆菌AMCC 100218菌株是1株具有防治根结线虫病潜力的生防细菌。     

A nematicidal metabolite from Verticillium chlamydosporium

A bioassay‐directed fractionation of cultures of the fungus, Verticillium chlamydosporium, demonstrated nematicidal activity, due mainly to phomalactone. Compared with aldicarb, the lethal activity against Meloidogyne incognita was less, but its activity in suppressing root invasion was similar. The extract also contained monorden. © 2000 Society of Chemical Industry