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湖南水稻主推品种对旱稻孢囊线虫的抗性及评价方法 总被引：1，自引：0，他引：1
【目的】旱稻孢囊线虫是一种水稻上重要的病原线虫。筛选抗虫种质资源对抗病品种的选育至关重要。【方法】通过室内二龄幼虫接种和田间自然病圃鉴定,以单株平均孢囊数、相对抗病指数和繁殖系数法评价了湖南省51个主推的水稻品种对旱稻孢囊线虫的抗性。【结果】在供试水稻品种中未发现有免疫和高抗品种。室内接种条件下,在24个中稻品种中,依据单株平均孢囊数评价,仅广两优2010表现为抗;依据相对抗病指数评价,广两优2010、准两优527、广两优1128 3个品种为抗;在27个晚稻品种中,依据单株平均孢囊数评价,盛泰优9712、准两优608、农香优204、岳优9264、岳优3700、中浙优1号、岳优27、湘晚糯1号、贺优50、Y两优9918共10个品种为抗;而依据相对抗病指数评价,湘晚糯1号、贺优50、Y两优9918表现为中感。在田间自然病圃条件下,依据繁殖系数Pf/Pi评价,筛选出9个晚稻抗性品种,鉴定结果与室内接种相对抗病指数法基本一致。【结论】室内接种相对抗病指数法可以作为评价水稻品种对旱稻孢囊线虫抗性的有效方法。 相似文献
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混配制剂中拮抗细菌菌株Pf7-14在稻株上的群体数量及其对水稻纹枯病的防治 总被引：1，自引：0，他引：1
菌株Pseudomonas fluoresecens 7-14(pf7-14)显著地抑制了水稻纹枯病.在温室条件下,在水稻(品种为IR72)健株和纹枯病菌(Rhizoctonia solani)接种的病株上于分蘖盛期分别喷雾Pf7-14、混剂(Pf7-14+井冈霉素),菌株Pf-14对用于标记的抗生索萘啶酮酸(Nalidixic acid)具有天然的抗性,以上两处理中Pf7-14的浓度相同,约为2.2×108 cfu/mL,应用稀释平板法,在喷雾后的不同时期,在含萘啶酮酸100μg/mL的培养基上回收Pf7-14.结果表明:无论是在健株还是在病株上,在两批试验中.混剂中Pf7-14的种群数量总是高于其在单剂的数量,在健株上,应用1～4 d,两者显著性相差1.69～2.96倍(P=0.05).在病株上,第4～7 d,两者显著性相差1.74～3.70倍.田间试验结果表明,无论是一次防治,还是两次防治,与两个单剂相比,混剂(Pf7-14+井冈霉素)对水稻纹枯病的防治效果得到显著性提高.两次防治中,混剂的防治效果为83.46%,而单剂Pf7-14和井冈霉素的防治效果分别为56.92%和73.72%. 相似文献
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The characteristically clustered occurrence and low level of mobility of Heterodera schachtii and Rhizoctonia solani in the soil and the induction of stress symptoms in the sugar beet canopy make them ideal targets for site-specific arrangements with precision agriculture tools. A field site infested with H. schachtii and R. solani was investigated in 2009 with near-range and aerial hyperspectral sensors during the growing season. At 31 sample points ground truth data for incidence and severity of the two organisms were collected and geo-referenced. Spectral vegetation indices computed from reflectance measurements obtained from two flight campaigns (AISA, 17th of June; HyMap, 28th of August) and the near-range spectroradiometers were significantly correlated (P < 0.01) with symptoms caused by the nematode or Rhizoctonia crown and root rot. A supervised classification with Spectral Angle Mapper of leaf symptoms induced by the organisms resulted in a classification accuracy of 72 and 64% for the AISA and HyMap data, respectively. The results demonstrated that remote sensing in combination with geographic information system technologies can be used effectively for the detection and mapping of symptoms caused by beet cyst nematode and Rhizoctonia crown and root rot. 相似文献
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荧光假单胞菌Pf.X16L2与丛枝状菌根真菌Glomus mosseae在小麦根圈内的相互关系 总被引：1，自引：0，他引：1
运用发光酶基因标记及其发光强度检测,SDH酶活染色等技术,在根盒－土壤微宇宙及塑料盒栽系统中,研究了发光酶基因（luxAB)标记的荧光假单胞菌菌株Pf.X16L2与丛枝状菌根真菌摩西球孢囊霉Glomus mosseae两者在小麦根圈的相互关系。Gl.mosseae对Pf.X16L2的种群密度和生理活性都有着抑制作用。因而能降低小麦根圈对Pf.X16L2的富集作用,而Pf.X16L2在一定程度上能提高Gl.mosseae的菌根感染率,但会降低菌丝中琥珀酸氢酶（SDH）活性,两者可共同促进小麦中后期的生长。 相似文献
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Summary The effect of soil pH on yield losses due to potato cyst nematodes (Globodera pallida) was investigated in experiments in the field and in a semi-controlled environment. Through annually liming a reclaimed peat
soil with about 22% organic matter, plots with pH levels of 4.5, 5.0, 5.5, 6.0 and 6.5 were obtained. In 1990 potato yields
in these plots decreased from 45 t/ha at pH 4.5 to 33 t/ha at pH 6.5, whereas the nematode densitites decreased from about
18 to 9 juveniles per g soil. In a container experiment a strong interaction was recorded between soil pH and the presence
of nematodes. Tuber yields were about 11% lower at pH 6.5 than at pH 4.5 in the absence of nematodes, but about 44% lower
when an initial population of 27 juveniles per g soil was present. 相似文献
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