江西早熟梨病害发生调查

于2009年3月上旬至10月下旬,每月1次定期到金溪和南昌市郊调查江西早熟梨病害,共调查出早熟梨病害9种,其中以梨轮纹病发生最重,其次是梨锈病和梨角斑病。梨角斑病是近年迅速上升起来的一种病害,应加强防治和研究。     

韩国梨树上发生的两种新的细菌病害及其检疫意义

韩国新近发生两种梨树细菌性病害，梨枝条黑枯病和梨褐色叶枯病，已流行并造成严重危害，两种病害均可随种苗传播。梨枝条黑枯病的症状、病原及危害与梨火疫病极其相近，其病原与梨火疫病菌的关系还未完全研究清楚。梨褐色叶枯病也显著影响梨的产量。建议国家立即对这两种病害采取检疫措施，以防止这两种病害传入我国。     

早熟梨和晚熟梨哪个受欢迎

今后梨果的发展动向是什么?市场上适合发展早熟品种还是晚熟品种?就价位而言,早熟梨价格在去年已明显回落,从前几年的每kg8~10元,下降到了每kg2元左右,已与普通梨价格接近。早熟梨降价所反映的市场信息是,市场上早熟梨的供求关系已达平衡,而按早熟梨从无到有的发展时间推测,今后几年中其产量还将增加,市场供应量会进一步加大。再有,就耐贮性而言,当前主推的早熟梨品种黄冠梨、黄金梨属沙梨系列,本身耐贮性较差,以目前的保鲜水平,即以冷风库为主、气调库很少的现状来说,早熟梨一般贮存期为30～50d,不能超过60d。因此,如果今后早熟梨产量增加,…     

江西早熟梨病虫害发生现状及综合治理

目前江西省梨园发生的病虫害主要有：梨轮纹病、梨黑斑病、梨锈病、梨炭疽病、梨瘿蚊、梨木虱、梨小食心虫、梨茎蜂、红蜘蛛、二叉蚜、黄粉蚜,其中枝杆病害和根部病害有扩延的趋势,而胴枯病是近年发现的新的病害。对江西梨园病虫害发生的情况进行概述,并根据江西气候特点以及对部分虫害监测情况提出综合治理对策。     

梨火疫病的世界性传播现状及检疫对策

梨火疫病是梨、苹果及许多蔷薇科寄主植物上一种毁灭性的细菌病害,已经成为各国有关科学家的普遍共识。自从1780年在美国纽约Hudson河流域最先观察到之后,梨火疫病在此后的200多年时间内,由于人为因素的传带,传至世界上3个重要的国家,进而促使梨火疫病在世界范围内传播。至今,据官方证实,已有33个国家或地区发生了梨火疫病,其中北美     

检测梨火疫病菌的过敏性寄主

梨火疫病（ＦｉｒｅＢｌｉｇｈｔ）是梨、苹果及许多蔷薇科植物上一种毁灭性的细菌病害,也是我国进境植物应检疫的危险性病害之一。植物病原假单胞菌的过敏反应测定通常在烟草和蕃茄上进行,稻白叶枯病菌的过敏性反应测定还可在蚕豆叶上进行［１］,１９７３年Ｌａｉ和Ｈ...     

用离体巴梨枝条测定梨火疫病菌的致病性

梨火疫病Erwinia amylovora是蔷薇科仁果类果树上一个毁灭性的细菌病害,主要危害花、叶和嫩梢,同时也发生在果实、枝条和树干上。病原菌寄主范围十分广泛,多达140多种植物。此病可通过果实、接穗、苗木、风雨、昆虫甚至远距离     

安徽主栽梨品种对梨锈病的抗性研究初报

采用定点定树调查不同梨品种对梨锈病的抗性，结果表明，砀山酥梨最感病，其次为明月梨、大青皮梨；莱阳梨居中；康德梨和开桦梨抗病。     

梨叶部病害与梨叶早衰脱落相关性分析

为明确南方梨产区造成梨早衰落叶的原因,本研究对梨叶部病害的发生与早期落叶间的关系进行了调查分析。结果显示:4种叶部病害(梨斑点病、褐斑病、黑斑病和黄脉病)中,除黄脉病外,不同年份间其余3种病害的发生程度与早期落叶率均呈显著正相关;不同品种、果园和时段间这3种病害均呈极显著正相关;7-9月间梨早衰脱落叶片斑点病发病率均达到100%,显著高于其他3种病害;病害防控对减少梨叶部病害发生和降低早期落叶率具有同效性,由此认为防治以斑点病为重点的叶部病害,是控制梨树落叶早衰问题的关键。     

辽宁梨树间座壳菌枝枯病的病原鉴定

 在辽宁兴城“锦丰”梨栽植园出现一种新的枝干病害,该病害主要发生在主干及侧枝,主要症状为主干呈现黑斑、枝条枯萎。本研究对该病害进行了系统调查及病原物分离培养;经形态学观察、柯赫氏法则验证,ITS、EF1-α、CAL、TUB和HIS基因联合建树分析,确定引起“锦丰”梨枝枯病的病原菌为间座壳属真菌Diaporthe nobilis。     

不同植物秸秆对番茄及南方根结线虫的影响

为有效防治南方根结线虫,本试验研究了添加不同剂量的玉米秸秆(8.32、4.16、2.08g/kg)、辣椒秸秆(4.16、2.08、1.04g/kg)和茵陈蒿秸秆(4.16、2.08、1.04g/kg)对温室大棚番茄及根结线虫的影响。结果显示,在根结线虫侵染的土壤中添加植物秸秆后30d,玉米秸秆(4.16、2.08g/kg)对番茄株高有显著影响,辣椒(4.16、1.04g/kg)和茵陈蒿(4.16、2.08g/kg)秸秆对番茄茎粗影响显著;60d时经茵陈蒿处理的番茄植株比对照生长发育良好,对形态指标的影响程度依次为茎粗开花分枝;120d时番茄的茎粗、分枝和果实重量均显著高于对照。末次接种后20d调查,每种作物秸秆处理以高剂量对根结线虫的防治效果最好,防治效果依次为:茵陈蒿秸秆辣椒秸秆玉米秸秆,分别为79.60%、71.32%、68.89%,表明茵陈蒿秸秆处理既可降低根结线虫危害程度,又可提高番茄产量。本研究为温室大棚有效防治根结线虫提供了依据。     

冬型中国梨木虱在梨树不同部位的产卵特点

昆虫母代产卵部位的选择特点直接影响到子代的生存适应性,但已有研究对冬型中国梨木虱产卵部位选择特点尚未明确。本研究调查了冬型中国梨木虱随时间变化在梨树花芽、叶芽、枝条基部、花柄、幼叶上产卵特点的变化。结果表明,冬型梨木虱产卵期约45 d,以枝条基部刻痕处着卵量最大,显著高于其他部位。冬型梨木虱产卵部位的选择随梨树的物候变化而变化:萌芽前,优先选择枝条顶芽,其次在腋芽和枝条基部刻痕处产卵;花期和展叶期,花芽、叶芽、枝条基部刻痕处着卵量下降,主要于花柄和幼叶部位产卵;冬型梨木虱产卵部位的选择顺序依次为花芽、叶芽、枝条基部、花柄、幼叶。本研究明确了冬型梨木虱在梨树不同部位产卵的变化特点,研究结果可用于指导梨木虱防控。     

莱阳地区梨锈病防治适期研究

在山东莱阳地区,梨锈病菌冬孢子角自梨花现蕾期开始陆续成熟,成熟的冬孢子角遇1.5 mm/d以上的降雨,萌发产生担孢子。经2～3次降雨后,冬孢全部萌发,以后不再产生担孢子。梨树初花后35 d内对锈病最敏感,即为防治期。若该期内降雨量大于1.5 mm/次、叶面结露时间长于7 h/次,担孢子即可侵染。其侵染量与梨园周围越冬菌原的数量、降雨持续时间和品种抗病性等因子有关。田间试验表明:担孢子侵染后至病斑显症前(约7 d)是内吸性杀菌剂防治的有效时期。病斑显症后只有少数杀菌剂能抑制病斑扩展,20.67%氟硅唑乳油、10%苯醚甲环唑水分散粒剂和15%三唑酮可湿性粉剂3种药剂在病原菌侵入前喷施能有效地抑制担孢子侵染,持效期约7 d;担孢子侵染后喷药能有效抑制病斑显症,因此,要特别关注梨树初花时第1次降雨后梨锈病的防治。     

Effects of Angular Leaf Spot and Rust on Yield Loss of Phaseolus vulgaris

ABSTRACT Three field experiments were conducted in 1997, 1998, and 1999 to investigate the effects of angular leaf spot and rust, separately or combined, on host growth and yield of individual bean plants (Phaseolus vulgaris). In each experiment, three treatments were established by inoculating cv. Carioca with Phaeoisariopsis griseola, Uromyces appendiculatus, or with both pathogens. An additional control treatment was not inoculated, but was sprayed with a fungicide. In the 1997 and 1999 experiments, angular leaf spot reached higher disease levels than rust, whereas in 1998, rust was more severe than angular leaf spot. Host growth, expressed as healthy leaf area duration (HAD), and yield were the highest in 1997 and lowest in 1998. In each experiment, the treatments did not differ significantly to the area under leaf area progress curve, HAD, and healthy leaf area absorption (HAA). All inoculated treatments had significantly more severe disease and less yield than the control treatment. Based on the analysis of 60 plants in each experiment, yield was not related to the areas under disease progress curve for either or both diseases. In 1997 and 1999, yield was related to HAD (R(2) = 0.57 and 0.43) and HAA(R(2) = 0.60 and 0.55). Based on the combined analysis of all 36 plots, angular leaf spot reduced the leaf area because of defoliation, whereas rust did not affect the leaf area. Rust reduced yield more than four times that of angular leaf spot, although the decrease in photosynthesis to angular leaf spot was twice that of rust.     

抗黑星病芽变鸭梨组织结构、生理生化与抗病性关系研究

对一株抗黑星病芽变‘鸭梨’的叶片组织结构和生理生化特性进行了研究,发现其叶片蜡质含量高、栅栏组织双层出现时间早、厚度大、海绵组织结构致密、气孔数目少,推断这些特性决定黑星病菌分生孢子不易侵入叶片内部;叶绿素含量高为植株抗病性提供了生理基础,可溶性糖含量低有可能抑制黑星病营养菌丝在细胞间的生长和扩展。通过研究该抗黑星病芽变‘鸭梨’的抗病机理,为‘鸭梨’抗黑星病育种提供了理论依据。     

Control of brown spot of pear by reducing the overwintering inoculum through sanitation

Stemphylium vesicarium, the causal agent of brown spot of pear, overwinters in the leaf residues of pear and herbaceous plants of the orchard floor. Pseudothecia of the teleomorph, Pleospora allii, are formed on these residues where they produce ascospores. New methods were tested aimed at reducing this overwintering inoculum and increasing the efficacy of control of brown spot of pear. Sanitation methods were evaluated in nine trials in Girona (Spain) and Ferrara (Italy) over a 4-year period. The sanitation methods were leaf litter removal in December to February, and application of biological control agents (commercial formulates of Trichoderma spp.) to the orchard ground cover from February to May. Fungicides were also applied to the trees during the pear-growing season, scheduled according to the BSPcast model. The different methods were tested as stand-alone applications or in combination. All methods consistently reduced the disease incidence at harvest on fruit with an efficacy between 30 to 60% for leaf litter removal and more than 60% for the combination of leaf litter removal and biological control. Efficacy of sanitation alone (leaf litter removal and biological control) in reducing the brown spot level on fruit was similar in most of the trials to the efficacy obtained when fungicides were applied alone. However, integration of sanitation methods and fungicides did not improve the efficacy of disease control over the level provided by fungicides alone.     

广西苦瓜棒孢叶斑病的病原鉴定

<正>0 引言苦瓜(Momordica charantia L.)又称为凉瓜,是葫芦科苦瓜属一年生攀缘植物,兼具食用与药用价值,也是广西“南菜北运”的重要瓜类蔬菜^[1]。苦瓜棒孢叶斑病是苦瓜大棚生产中的一种常见病害,主要发生于苦瓜生长的中后期,以叶片为害为主。据调查,广西大棚中苦瓜棒孢叶斑病发病率约为40%,严重影响苦瓜的生长发育。该病害在韩国和我国的山东均有报道^[2-3]。棒孢病菌产生的cassiicolin毒素蛋白是主要的致病因子,     

生物素标记cDNA探针杂交检测梨树上3种潜隐病毒研究

 本研究合成了苹果茎沟病毒(ASGV)、苹果褪绿叶斑病毒(ACLSV)和苹果茎痘病毒(ASPV)的生物素标记cDNA探针,对斑点杂交和免疫印迹杂交检测这3种病毒的效果进行了分析。以含ACLSV和ASGV克隆片段的大肠杆菌菌液为样品时,斑点杂交检测灵敏度分别为80 cfu/μL和50 cfu/μL。以离体培养砂梨植株为材料,采用斑点杂交法检测砂梨离体培养植株粗提液中的3种病毒,均产生强的杂交信号,且特异性好。比较斑点杂交和ELISA检测病毒含量相对较低的热处理再生植株中ASGV和ACLSV,结果表明斑点杂交具有较高的灵敏度。组织印迹杂交检测砂梨离体植株ASGV和ACLSV的结果显示,这2种病毒在离体植株的各部位均有分布,自基部至茎尖各部位印迹均产生很强的杂交信号。