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11.
应用TaqMan-MGB探针进行松材线虫的实时荧光定量检测技术研究 总被引:7,自引:0,他引:7
松材线虫是国际公认的最重要的检疫性有害生物之一,也是我国2类检疫危险性有害生物,我国口岸多次从货物的木质包装中截获该线虫。由于松材线虫与拟松材线虫在形态上极其相似,难以区分,幼虫更无法用于鉴定。传统的形态学鉴定、生化以及其他分子技术等方法存在费时、准确度不高、灵敏度低等缺点,不易形成标准。我们设计筛选一对引物以及一条MGB探针,对松材线虫进行实时荧光PCR检测。建立了一条从1 pg到104pg标准曲线,相关系数r=0.965。该检测方法省时、准确、快速、无污染。 相似文献
12.
Roger Voisin Maria-Jose Rubio-Cabetas Jean-Claude Minot Daniel Esmenjaud 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(1):103-108
Penetration, development and emigration of M. arenaria in the roots of three Myrobalan plum (Prunus cerasifera) clones genetically characterized for their resistance to root-knot nematodes (RKN) were studied during the 10 (penetration) and 15 (emigration) days following the date of inoculation (D) of 2500 juveniles (J2s) per plant into the soil. Miniaturized tests were conducted on the two resistant clones P.2175 (Ma1 gene) and P.1079 (Ma2 gene) and the susceptible clone P.2032 (recessive for both genes), obtained from micropropagated plantlets and grown in mini-containers under controlled conditions at 25°C in a growth chamber. For penetration and development studies, nematodes in the roots were recovered by the acid fuchsin-lactophenol staining technique. Equivalent numbers of J2s were recovered in all the clones at D+1 and D+2. Subsequently, the numbers increased rapidly in P.2032 and were significantly different from those in P.1079 and P.2175 that remained at a low level. No swollen larvae were observed in the resistant clones. In P.2032, the first swollen larvae were observed at D+4, the first females were observed at D+12, whereas the first females with attached egg sacs and the first new-generation J2s were obtained between D+21 and D+28. Our data suggest that the resistance phenomenon does not act on the very early nematode penetration but acts later by preventing feeding-site induction and development into the third-stage. For emigration studies, plants in which J2s had been allowed to penetrate for two days (from D to D+2) were washed free of soil, repotted and then, after various periods of growth, soil-free roots were placed under a mistifier to evaluate the numbers of emigrating individuals. Emigration of J2s from the roots occured mainly from D+2 to D+4 in all the genotypes and was very limited from D+4 to D+10. There was no significant differences in the number of emigrated juveniles between the resistant and susceptible clones, indicating that emigration cannot explain the difference in the numbers of nematodes recovered in the roots. 相似文献
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木醋液的杀线活性及对根结线虫病的防治效果研究 总被引:9,自引:1,他引:9
【目的】初步探究木醋液对根结线虫2龄幼虫的抑制作用,以及木醋液及其配剂对根结线虫病的田间防治效果。【方法】采用浸渍法测定不同稀释浓度的木醋液对根结线虫2龄幼虫抑制作用,根据实验室测定结果设计小区试验,进行木醋液及其配剂对石榴根结线虫病、番茄根结线虫病的大田防治。【结果】不同稀释浓度的木醋液对4种常见根结线虫的2龄幼虫均有抑制作用,随着稀释倍数的增加,抑制作用减小。木醋液稀释浓度为150倍处理72 h时,北方根结线虫、花生根结线虫、南方根结线虫、爪哇根结线虫的校正死亡率分别达到了76.3%、78.4%、77.9%和72.2%。木醋液和木醋液配剂对石榴根结线虫病有较好的防治效果,防治效果分别达到了63.9%和50.5%。木醋液和木醋液配剂对番茄根结线虫病的防治效果,寻甸分别为54.1%和28.6%,个旧的为27.8%和19.6%。【结论】初步证明木醋液对根结线虫2龄幼虫有抑制作用,对石榴根结线虫病和番茄根结线虫病有防治效果,对防治根结线虫病有研究价值、应用价值和开发前景。 相似文献
16.
毛头鬼伞Coprinuscomatus,又名鸡腿菇、鸡腿蘑等,隶属真菌门、鬼伞属真菌。该菌肉质肥厚嫩白,鲜美可口。营养丰富,是一种诱人的美味食品。除此之外,该菌还具有独特的医疗保健功效,其味甘性平,有益脾健胃、清神宁智、助消化、增进食欲、治疗痔疮、降低血糖等多种药用功能阻引,是一种极具商业潜能的食药兼用真菌。 相似文献
17.
The effects of inoculation with two AM fungi (M1, Glomus caledonium; M2, Glomus spp. and Acaulospora spp.) and a fungivorous nematode Aphelenchoides sp. on growth and arsenic (As) uptake of Nicotiana tabacum L. were investigated in soils contaminated with a range of As. The reproduction of Aphelenchoides sp. was triggered by the co-inoculation of AM fungi regardless of AM fungal isolates and As levels. Stimulative effects of Aphelenchoides sp. on the development of mycorrhiza, slightly different between two AM fungi, were found particularly at the lowest As level. Irrespective of mycorrhizal inoculi, increasing soil As level decreased plant growth, but increased plant As uptake. Co-inoculation of AM fungi and Aphelenchoides sp. led plants to achieving further growth and greater As accumulation at the lowest As level. Results showed that the interactions between AM fungi and fungivorous nematodes were important in plant As tolerance and phytoextraction at low level As-polluted soil. 相似文献
18.
Hair follicle neoplasms occur in many different species, including humans. In domestic animals, they are most common in dogs. Most hair follicle tumors are benign, but malignant neoplasms can also occur. To diagnose hair follicle neoplasms, a thorough knowledge of follicular anatomy is important, given that follicular tumors are classified according to the differentiation pattern seen in the corresponding part of the normal hair follicle. This review focuses on the key diagnostic features of hair follicle tumors and follicular cysts in dogs and cats. 相似文献
19.
Identification and resistant characterization of legume sources against Meloidogyne incognita 下载免费PDF全文
Root-knot nematodes(RKNs; Meloidogyne spp.) are becoming a serious problem in legume production. This study identified Vigna genotypes exhibiting resistance to M. incognita(RKN) and characterized the modes of the resistance to M. incognita. In total, 279 accessions from 21 Vigna species were screened for resistance based on a galling index(GI) and an egg mass index(EI). Seven accessions were highly resistant to RKN with GI≤25, namely JP74716(V. mungo var. mungo; cultivated black gram), JP107881(V. nepalensis), JP229392(V. radiata var. sublobata; wild mungbean), Aus TRCF118141(V. unguiculata subsp. unguiculata; cultivated cowpea), Aus TRCF306385(V. unguiculata subsp. unguiculata), Aus TRCF322090(V. vexillata var. vexillata; wild zombi pea) and JP235929(V. vexillata var. vexillata). JP229392 and Aus TRCF322090 were the most resistant accessions having EI values of 18.74 and 1.88, respectively. Continuous culture of M. incognita on both JP229392 and Aus TRCF322090 resulted in a weakness in pathogenic ability for this RKN. The resistance in JP229392 and Aus TRCF322090 to RKN appeared to be antibiosis that was associated with reduced nematode penetration, retardation of nematode development and impeding giant cell formation. The Vigna germplasm resistance to RKN identified in this study could be utilized as gene sources for the development of RKN-resistant Vigna cultivars. 相似文献
20.
为探索沼液抑制根结线虫的效果,本研究通过盆栽试验,以番茄为试供作物,对比了种植前沼液淹没土壤(BSS)、种植期间浇灌沼液(BS)和加热(HE)3种方法对根结线虫的防控效果。结果表明,与不采取任何措施的对照(CK)处理相比, BSS处理抑制根结线虫效果最为明显,防效高达97.1%,根结指数分别比HE和BS处理降低96.9%和92.9%。HE处理尽管在处理土壤后显著降低了根结线虫数量,但在最后破坏性取样时(结束试验)出现反弹,根结线虫数量甚至高于CK处理。对于土壤线虫群落,CK处理中以植食性线虫为主(81.8%);两个沼液处理中食细菌线虫占优势(平均78.3%),且其中的杂食捕食性线虫在土壤前处理后消失,在试验结束时又重新出现,但所占比例依然非常低。沼液淹水方式的高效防控效果揭示了利用沼液防控根结线虫的关键期在于线虫入侵到植物根部之前的幼虫期。然而,在盆栽系统中,沼液淹水的方式也对作物生长表现出了一定的抑制趋势。高量沼液施用防控病害的同时引发的植物毒害作用以及环境污染风险,需要进一步开展田间研究。 相似文献