高原鼠兔时空动态的元胞自动机模拟

利用高寒草甸和高原鼠兔(Ochotona curzoniae)的生态特征建立了元胞自动机模型,并通过模拟得到了高原鼠兔种群时空动态的规律。结果表明:高原鼠兔有效洞口的扩散量与扩散力的变化基本一致,扩散可减轻高原鼠兔对高寒草甸的危害;高原鼠兔对原栖息地的留恋指数α越小,高原鼠兔越易扩散;退化草甸上高原鼠兔密度越大,对已治理草地的入侵就越远;退化草甸恢复后,植被低矮时,入侵距离短、危害重,而植被较高时,入侵距离远、危害轻;全球气候变暖后,如果高原鼠兔的繁殖期不延长,则增温前后的种群动态相差不大;如果增温后高原鼠兔的生长期延长,在非退化高寒草甸上,增温前后种群动态差别不大,在退化高寒草甸上,高原鼠兔种群将迅速增大。     

草原机械喷雾灭鼠——工农36型机动喷雾机的应用

高原鼠兔和中华鼢鼠是青海牧区的主要害鼠。分布广、数量多,危害大,影响畜牧业的发展。我们应用工农36型机动喷雾机进行机械喷雾灭鼠试验,效果显著。 1.样地选择:灭鼠试验区在青海省门源种马场风匣口地区的冬季牧场,面积约为300公顷。植被有垂穗披碱草、苔草、羊茅、早熟禾、二裂委陵菜、蕨麻等,复盖度为60—70％,草层高度3—5厘米。灭鼠前、后10天,以堵洞盗洞法和开洞封洞法,分别统计有效洞数;计算灭鼠效果。     

新疆两种啮齿类动物的核型分析

本文以子午砂土鼠和草原兔尾鼠为材料,采用常规骨髓制片法制备染色体标本,对它们的核型进行了分析,其中子午砂土鼠和草原兔尾鼠分别为2n=50和2n=54,核型公式为:12(M)+14(SM)+22(A)和4(M)+4(ST)+44(A)。     

2种不育剂和1种抗凝血剂对藏北草原高原鼠兔的控制效果

2012年4月至2013年4月在藏北草原进行了炔雌醚、莪术醇和增效敌鼠钠盐控鼠试验。均配制成青稞药饵,投放药饵后第20、75和350天进行控效调查。结果显示:炔雌醚具杀灭高原鼠兔作用,20d校正灭效达72.24%,对成年雌雄鼠繁殖器官均能起到明显损坏作用,且适口性最好;增效敌鼠钠盐控鼠效果最好,20d校正灭效达94.46%;莪术醇也有一定效果,75d幼体比最低,总体看,3种药物均具有一定控制效果,有一定实际应用潜力,但还需进一步试验验证其控鼠效果。     

应用无人机(UAV)低空影像监测黄兔尾鼠鼠洞初探

黄兔尾鼠是新疆北部地区荒漠草原的主要危害鼠种之一。其灾害调查长期以人工地面调查为主。为探究无人机(UAV)低空遥感在黄兔尾鼠鼠洞调查中的适用性,选择巴音沟牧场典型鼠害区进行航拍试验,采用小型无人机作为低空遥感平台,获取研究区可见光航拍影像。采用极大似然法和面向对象分类方法提取鼠洞,通过混淆矩阵结合地面样方对分类结果进行精度评价。结果表明,应用UAV监测黄兔尾鼠洞穴的空间分辨率应不低于1.5 cm;极大似然法鼠洞分类精度为69%,而面向对象分类方法分类精度达91%,面向对象分类方法识别鼠洞正确率更高。UAV低空遥感在黄兔尾鼠灾害调查中表现良好,具有很好的应用和推广价值。     

大隆(TALON)灭鼠的试验研究

作者于1980年3～4月和7～8月间,在青海省天峻县和门源县草甸草原牧场进行了新杀鼠剂大隆杀灭我国西北草原主要害鼠—高原鼠兔(Ochotonacurzoniae)、中华鼢鼠(Myospalax fontanieri kukunoriensis)的试验研究。大隆对鼠兔的LD_(50)为0.1380mg/kg(0.1192～0.1568mg/kg),对鼢鼠的LD_(50)为0.4388mg/kg(0.2742～0.7022mg/kg)。 0.015％、0.030％和0.060％三种浓度大隆毒饵对鼠兔的现场灭效均达90％以上。一系列试验证明,大隆对草原害鼠的毒力强,使用浓度低,适口性好,无明显的耐药性,对天敌的危害性小。作者认为大隆可以应用于草原灭鼠,并可能有较好的前景。     

藏北草原高原鼠兔密度调查方法探讨

2006年对藏北高寒草原牧场的高原鼠兔种群密度进行了抽样堵洞调查,以夹捕法调查作为补充,同时通过捕尽法确定洞口系数约为0.11,在此基础上以有效洞口数推算调查点高原鼠兔绝对密度约为53.72只/hm2。通过相关分析,建立高原鼠兔种群-洞口密度增长模型,可根据洞口密度估算高原鼠兔种群密度,为西藏草原鼠类防治提供参考。     

新疆啮齿动物新种新亚种新记录种与某些鼠种的新分布

本文报告了近 10余年新疆啮齿动物分类、分布的新发现。其中有新种伊犁鼠兔 ,新亚种天山黄鼠尼勒克亚种 ;新疆新记录种大林姬鼠、高原鼠兔、藏鼠兔、柯氏鼠兔 ;中国新记录种戈壁阿尔泰山鼠平和草原鼠兔。此外还指出脂尾三趾矮跳鼠、小毛足鼠、长尾仓鼠、大沙鼠、水鼠平和鼹形田鼠等 6种动物的新分布地点。     

提高毒饵法灭鼠效果的探讨

灭鼠方法很多,目前提倡以肠道杀鼠剂为主的综合防治。当大范围内害鼠严重时,毒饵灭鼠工效高、成本低、使用得当能够迅速降低鼠密度。提高毒饵法灭鼠的效果在实践中有重要意义,如果一次灭褐家鼠效果为70％,7个月后就可恢复到原来的密度;一次灭鼠效果在90％以上,14个月才能恢复到灭鼠前的密度,相当于效果70％的两次灭鼠。 保证质量提高灭鼠效果是灭鼠实践中极需解决的问题。为此,提出以下几点建议: 一、正确使用杀鼠剂 自本世纪五十年代出现抗凝血杀鼠剂以来,杀鼠剂分为急性和慢性两种。通常,慢性杀鼠剂多用于灭家栖鼠,急性杀鼠剂多用于灭野鼠。正确使用灭鼠剂是提高灭鼠效果     

同德牧场主要害鼠的分布及数量调查

同德牧场位于青海省同德县东北部巴滩地区,面积约为26万亩,其中耕地6万余亩。该区草场植被属高山草甸化草原类型,土壤以暗栗钙土为主。天然草场以针茅、苔草及早熟禾为健群种。唯牧场东北隅巴水以北地区牧场为半荒漠类型草原草场,植被健群种为芨芨草、狼毒等。此区历来鼠害严重,1964年曾使用飞机投散磷化锌毒饵法,对大规模灭杀达乌尔鼠兔(Ochotona daurica)(以下简称鼠兔),取得了良好的效果。此后七、八年间鼠兔的数量一直较低,1973年以后逐渐回升,在不少地块已接近或恢复     

我国北方葡萄根癌病的发生规律及药剂防治

葡萄根癌病在我国北方地区发生分布广泛,部份葡萄园发病严重,感病品种病株率高达100％。葡萄的根、根颈、枝蔓均能发病,以根颈部冠瘿瘤最多。在受冷伤害严重的葡萄园,枝蔓上发病也重,且成为植株死亡的主要原因。在内蒙古包头市一带,5月下旬发病,6月中旬至8月为发病盛期,9月下旬停止发病。温度、湿度及降水与病害关系密切,葡萄受霜冻和冬季低温的影响,增加了病菌新的侵染点,加快病害的发生发展。葡萄品种抗病性差异显著,玫瑰香、巨峰等高度感病,罗也尔玫瑰、康拜尔、贝达等抗病性强。室内药效测定和田间防治试验,抗菌剂401、402,福美砷和石硫合剂渣子等抑菌力强,并有较好的防治效果。     

棉铃疫菌的越冬存活

 用MTT活体染色法,对棉铃疫苗(Phytophthora boehmeriae Sawada)的存活越冬进行了研究,结果表明:孢子囊和卵孢子均可在棉田土中的病残体(烂钤壳,棉籽)上存活。其中孢子囊可存活3~4个月,且其存活率可高达58.0%,认为孢子囊在棉铃疫病的再侵染过程中起重要作用。但孢子囊在1月份温度达零度时就全部死亡,不能越冬。而卵孢子在历经1990年至1991年冬季零度以下76天(其中最低温度达-2.8℃)后仍可以存活,在存活300天以后其存活率达48.8%,证明卵孢子是毫无疑问的越冬菌态。生物测定,越冬后卵孢子形态观察,卵孢子萌动变化与温度的关系表明,越冬存活的卵孢子可以成为棉铃疫病的初侵染来源。     

组织化学技术快速检测泡桐丛枝病研究

 迪纳氏染色和萤光显微镜技术——苯胺蓝染色法,和DAPI染色法,可从感染泡桐丛枝病的嫩茎和叶柄及将MLO转接到长春花上,表现典型症状的嫩茎和叶柄中诊断MLO的侵染。病株切片的迪纳氏染色阳性,健株切片阴性。苯胺蓝染色病株韧皮部产生的特异性萤光区域比健株大。DAPI染色可直接检测韧皮部组织中的MLO,而且韧皮部萤光强度与MLO的密度和外部症状严重度呈正相关。三种染色方法比较结果说明,DAPI染色法是一种灵敏度高,特异性更强的泡桐丛枝病类菌原体检测方法。     

Characterisation of volatiles produced from <Emphasis Type="Italic">Bacillus megaterium</Emphasis> YFM3.25 and their nematicidal activity against <Emphasis Type="Italic">Meloidogyne incognita</Emphasis>

A member of plant growth-promoting rhizobacteria, Bacillus megaterium YMF3.25, was demonstrated to be an efficient biocontrol agent (BCA) against root-knot nematode Meloidogyne incognita. Results from three-compartmented Petri dish tests and a pot experiment indicated that the bacterial culture could significantly inhibit the hatch of eggs and reduce infection of the nematode through production of nematicidal volatiles. After analysis by gas chromatograph/mass spectrometer and confirmation with commercial pure compounds, the nematicidal volatiles produced by the bacterium were characterised to include mainly the benzeneacetaldehyde, 2-nonanone, decanal, 2-undecanone and dimethyl disulphide, which were active against to both juveniles and eggs at the concentration of 0.5 mmol. Six compounds (phenyl ethanone, nonane, phenol, 3,5-dimethoxy-toluene, 2,3-dimethyl- butanedinitrile and 1-ethenyl-4-methoxy- benzene) with nematicidal activityies of 30%–63% also contributed to nematicidal efficacy of the bacterium.     

A Laboratory Assay for Phytophthora infestans Resistance in Various Solanum Species Reflects the Field Situation

Physiological and molecular research on resistance responses of Solanum tuberosum cultivars and partially resistant Solanum species to Phytophthora infestans requires a reliable resistance test that can be used in the laboratory. Laboratory tests performed on detached leaves and intact plants were compared with field tests for similarity of late blight reactions. Detached leaves from field-grown plants were as resistant as detached leaves from climate chamber-grown plants when challenged with P. infestans. However, detached leaves incubated in covered trays at high relative humidity were more susceptible than detached leaves kept in open trays or leaves on intact plants. The incubation conditions of detached leaves in covered trays rather than detachment itself appeared to affect the resistance expression. Detached leaves of some wild Solanum genotypes became partially infected, whereas intact plants were completely resistant when inoculated. Inoculation of leaves on intact plants, however, resulted in lower infection efficiencies. These limitations should be taken into account when choosing the appropriate inoculation method for specific purposes. For resistance screening, laboratory tests proved to be a good alternative for field tests. The ranking of resistance levels for twenty plant genotypes was similar under laboratory and field conditions.     

Detection and identification of Xanthomonas arboricola pv. pruni from symptomless plant material: results of an Italian test performance study

Xanthomonas arboricola pv. pruni, the causal agent of bacterial spot disease of stone fruits, is a regulated quarantine pathogen in the European Union, listed as an A2 pest by the European and Mediterranean Plant Protection Organization (EPPO). Because detection and identification of this pathogen is key for its management and to ensure the production of pest free propagation material, it should be based on reliable tests, in particular when dealing with symptomless material. The current EPPO diagnostic Standard (PM 7/64) does not provide specific molecular methods for detection of this pest. The present paper summarizes the results of a test‐performance study (TPS) to validate, at a national level, a detection procedure for this bacterium. A working group was established in order to evaluate the performance criteria for tests included in the current EPPO Standard, and for a conventional PCR. On the basis of the obtained performance criteria, a diagnostic procedure was elaborated and then applied to perform an inter‐laboratory comparison. Screening tests for the detection of the bacterium on symptomless plant material based on IF and/or PCR were proposed, in parallel with isolation on agar media. For identification two methods were suggested: a molecular test or IF. This paper reports on the results of the TPS and proposes a flow diagram for the detection and identification of X. arboricola pv. pruni.     

Studies on the potential use of Pasteuria penetrans as a biocontrol agent of root-knot nematodes (Meloidogyne spp.)

Some aspects of the interaction of the bacterial parasite Pasteuria penetrans and the root-knot nematode ( Meloidogyne spp.) were investigated in laboratory and pot experiments. The variable spore attachment on juveniles exposed to water suspensions of the bacterium is probably attributed to differential susceptibility of biotypes within a heterogeneous Meloidogyne population. The relationship between spore concentration and attachment level is not linear over a range of spore dosages, indicating that even at very high spore concentrations the number of spores capable of attachment may not be present in excess and it is difficult to ensure sufficient numbers of spores to ensure infection will attach to all nematodes. Attempts to apply the bacterium in conditions such as might occur in seedbeds did not suppress nematode multiplication after transplanting in nematode-infested soil, indicating that the only effective application method is a thorough spore distribution in the planting sites. Two major constraints were revealed: high levels of spore attachment to juveniles does not always guarantee a significant reduction of egg laying and this is greatly influenced by the Meloidogyne biotype. Furthermore, the cumulative effect of the parasite in reducing Meloidogyne populations over several crop cycles was less than expected as the bacterium reduced intra-specific competition for the food supply and the less damaged root enabled many nematodes to survive.     

Spontaneous infection of white laboratory mice with Emmonsia crescens Emmons et Jellison, 1960 under natural conditions

Fifty white laboratory mice were planted in a microbiotope in which adiaspiromycosis has been detected in 52 Microtus arvalis during the last 10 years. Four of the white mice became infected with adiaspiromycosis. Serological tests revealed the infection in two mice exposed for 3 months. After 4 months' exposure, another two mice were found to be infected and the positive serological results were confirmed by microscopical examination which revealed adiaspores in their lungs. The infection was thus detected by serological methods sooner than by microscopical examination.     

卵孢白僵菌优良菌株的筛选和选育

从不同地区采集并分离到卵孢白僵菌菌株１７个，其中菌株Ｂｅａｕｖｅｒｉａｔｅｎｅｌｌａ２４一１对大黑鳃金龟幼虫的室内致病力高达７３．３％。通过单孢分离、紫外线照射分生孢子和原生质体的诱变方法，获得了比出发菌株Ｂ．ｔｅｎｅｌｌａ２４一１产孢量高２倍以上，毒力提高０．５４～１．７９倍的优良菌株４个。     

Potassium phosphate induces systemic protection in barley to powdery mildew infection

In laboratory tests, treatment of the first leaves of barley (Hordeum vulgare L cv Golden Promise) with potassium phosphate led to significant reduction in infection of the second leaves with the powdery mildew fungus Blumeria graminis f sp hordei Marchal, with a 25 mM treatment giving 89% reduction in infection. Although the optimal interval between phosphate treatment of the first leaves and mildew inoculation of the second leaves was 2 days, significant protection was still obtained if the interval was increased to 12 days. Protection against powdery mildew infection was not as effective when the potassium phosphate was applied as a seed treatment or root drench. Phosphate treatment of the first leaves led to significant increases in activities of phenylalanine ammonia lyase (PAL), peroxidase and lipoxygenase in second leaves. Enzyme activities, especially PAL and peroxidase, were increased further when second leaves of phosphate-treated plants were inoculated with powdery mildew. Phosphate treatment of the first leaves did not adversely affect plant growth and, in a field trial, 25 mM potassium phosphate provided 70% control of mildew and gave a small increase in grain yield.