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苏云金芽胞杆菌工程菌BIOT185对金龟子幼虫的田间防效及其安全性评价 总被引:1,自引:0,他引:1
为评价苏云金芽胞杆菌(Bacillus thuringiensis,Bt)工程菌BIOT185对金龟子幼虫的田间防治效果以及其中间试验水平的安全性,在河北省定州市花生田开展了两年的田间小区试验。调查结果表明,每mL含100亿芽胞的工程菌BIOT185悬浮剂稀释10倍和100倍处理对金龟子幼虫具有较好的防治效果,虫口减退率可达52.08%~70.51%,保果效果为50.40%~66.57%,说明高浓度的BIOT185可以有效控制金龟子幼虫的危害。利用平板菌落计数法结合PCR检测发现,在施药后的365 d中BIOT185在土壤中的菌量总体呈下降趋势;调查田间各小区的昆虫种群发现,工程菌BIOT185处理区与野生菌HBF-1、BT185以及对照区的昆虫种群差异不显著。说明BIOT185不会在土壤环境中大量残留,也不会影响花生田的昆虫种群。 相似文献
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[目的] 筛选对板蓝根根腐病有较强拮抗作用的生防菌株。[方法] 采用平板对峙法对137个板蓝根根际土壤样本中分离到的201株拮抗细菌进行测试。[结果] 筛选出1个对板蓝根根腐病菌有强烈抑制作用的菌株Bs-0728。结合显微镜观察确定Bs-0728菌株对板蓝根根腐病的主要致病菌茄腐镰刀菌(Fusarium solani)菌丝生长有较强的抑制作用,导致菌丝生长畸形,弯曲,部分细胞膨大。田间试验结果表明,Bs-0728的发酵液田间防效达72.97%,且增产86.26%。经形态观察、生理生化反应及16S rDNA 序列分析,初步将此拮抗细菌鉴定为枯草芽胞杆菌Bacillus subtilis。[结论] 枯草芽孢杆菌Bs-0728菌株是一株很有应用前景的生防菌株。 相似文献
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There are concerns that genetically modified soybean might threaten the genetic diversity of the wild soybean populations that are distributed in East Asia because genetically modified soybean has no crossing barrier with wild soybean. A simple and effective method to prevent hybridization via pollen flow is spatial separation between the two species because their hybridization occurs only when they grow in close proximity. Therefore, the invasiveness of wild soybean needs to be known in order to secure the appropriate distances. As wild soybean seeds are dispersed mechanically by pod dehiscence, an experiment was conducted in which white sheets were placed on the ground, concentric circles were drawn around the parent plants, and the number of dispersed seeds within each 0.5 m‐wide zone were counted. About 40% of the produced seeds were dispersed and the number of dispersed seeds gradually declined as the distance from the parent plants increased. The model that explained the relationship between the number and distance of the dispersed seeds was produced by using a generalized linear model procedure. More than 95, 99, and 99.9% of the produced seeds stayed within 3.5, 5.0, and 6.5 m after natural pod dehiscence. Knowing these values is useful for evaluating the level of invasive risk by mechanical seed dispersal. The goal of the work is to efficiently and deliberately prevent hybridization by isolating genetically modified soybean fields and wild soybean populations by vegetation management, including weeding and setting up specific‐width buffer zones. 相似文献
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Owen MD Young BG Shaw DR Wilson RG Jordan DL Dixon PM Weller SC 《Pest management science》2011,67(7):747-757
A six-state, 5 year field project was initiated in 2006 to study weed management methods that foster the sustainability of genetically engineered (GE) glyphosate-resistant (GR) crop systems. The benchmark study field-scale experiments were initiated following a survey, conducted in the winter of 2005-2006, of farmer opinions on weed management practices and their views on GR weeds and management tactics. The main survey findings supported the premise that growers were generally less aware of the significance of evolved herbicide resistance and did not have a high recognition of the strong selection pressure from herbicides on the evolution of herbicide-resistant (HR) weeds. The results of the benchmark study survey indicated that there are educational challenges to implement sustainable GR-based crop systems and helped guide the development of the field-scale benchmark study. Paramount is the need to develop consistent and clearly articulated science-based management recommendations that enable farmers to reduce the potential for HR weeds. This paper provides background perspectives about the use of GR crops, the impact of these crops and an overview of different opinions about the use of GR crops on agriculture and society, as well as defining how the benchmark study will address these issues. 相似文献
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内生固氮菌具有促生、病原菌的防治及生物固氮等作用,并且占据着植物组织内有利于营养供应和微环境适宜的生态位,是重要的微生物菌种资源。从菠菜根内分离筛选优势内生固氮菌7株,其中假单胞菌属(Pseudomonas)5株,红球菌属(Rhodococcus)和黄杆菌属(Flavobacterium)各1株。菌株Pseudomonas sp.BCE6和Pseudomonas sp.BC-E8固氮酶活性较高,分别为(13.19±0.32)和(12.11±0.96)C2H4nmol/(mg protein·h),与圆褐固氮菌(ACCC11103)的固氮酶活性具有极显著性差异(P0.01);菌株Pseudomonas sp.BC-E7具有固氮酶活性[(8.42±0.03)C2H4nmol/(mg protein·h)]、产IAA能力[(59.58±4.15)μg/m L]、ACC脱氨酶活性[(5.067±0.376)μmol/(mg protein·h)],拮抗立枯丝核菌ACCC36124(Rhizoctonia solani)、麦类赤霉病ACCC36272(Gibberella zeae)等4种常见土传病害。菠菜内生固氮菌Pseudomonas sp.BC-E7是一株多功能内生菌,具有较好的生产应用前景。 相似文献
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