共查询到20条相似文献，搜索用时 328 毫秒
1.
Abstract A survey conducted during 1979–81 in Bangladesh revealed 20 rice diseases, including two viral, two bacterial, 13 fungal, two nematode and one micronutrient deficiency problem. Of these diseases. 16 appeared as major during the period under report. The number of diseases were 17, 16 and 16 during the Boro. Aus and transplant Aman seasons, respectively, with 12 common in all three seasons. Thirteen diseases including bacterial blight, bacterial leaf streak, sheath blight, sheath rot, blast, brown spot, grain spot, stem rot and leaf scald were classified as major; and tungro, bakanae, cercospora leaf spot and zinc‐deficiency were classified as either major or minor, and were common to all regions. Diseases not common in all regions were stack burn, root knot, and ufra classified as major or minor, and false smut, seedling blight. Yellow dwarf and damping off which were always classified as minor. Diseases which were typical for Boro. Aus and transplant Aman seasons were seedling blight and damping off. Yellow dwarf, and false smut respectively. Aus the most humid and warmest season, and the coastal humid areas experienced more major diseases. Seasonal and regional differences in the disease incidence appeared related to agro‐climatic variations. 相似文献
2.
3.
Effects of Elevated Atmospheric CO(2) Concentration on the Infection of Rice Blast and Sheath Blight
ABSTRACT The effect of elevated atmospheric CO(2) concentration on rice blast and sheath blight disease severity was studied in the field in northern Japan for 3 years. With free-air CO(2) enrichment (FACE), rice plants were grown in ambient and elevated ( approximately 200 to 280 mumol mol(-1) above ambient) CO(2) concentrations, and were artificially inoculated with consist of Magnaporthe oryzae. Rice plants grown in an elevated CO(2) concentration were more susceptible to leaf blast than those in ambient CO(2) as indicated by the increased number of leaf blast lesions. Plants grown under elevated CO(2) concentration had lower leaf silicon content, which may have contributed to the increased susceptibility to leaf blast under elevated CO(2) concentrations. In contrast to leaf blast, panicle blast severity was unchanged by the CO(2) enrichment under artificial inoculation, whereas it was slightly but significantly higher under elevated CO(2) concentrations in a spontaneous rice blast epidemic. For naturally occurring epidemics of the sheath blight development in rice plants, the percentage of diseased plants was higher under elevated as opposed to ambient CO(2) concentrations. However, the average height of lesions above the soil surface was similar between the treatments. One hypothesis is that the higher number of tillers observed under elevated CO(2) concentrations may have increased the chance for fungal sclerotia to adhere to the leaf sheath at the water surface. Consequently, the potential risks for infection of leaf blast and epidemics of sheath blight would increase in rice grown under elevated CO(2) concentration. 相似文献
4.
Willocquet L Elazegui FA Castilla N Fernandez L Fischer KS Peng S Teng PS Srivastava RK Singh HM Zhu D Savary S 《Phytopathology》2004,94(7):672-682
ABSTRACT A simulation study was conducted to assess the current and prospective efficiency of rice pest management and develop research priorities for lowland production situations in tropical Asia. Simulation modeling with the RICEPEST model provided the flexibility required to address varying production situations and diverse pest profiles (bacterial leaf blight, sheath blight, brown spot, leaf blast, neck blast, sheath rot, white heads, dead hearts, brown plant-hoppers, insect defoliators, and weeds). Operational definitions for management efficacy (injury reduction) and management efficiency (yield gain) were developed. This approach enabled the modeling of scenarios pertaining to different pest management strategies within the agroecological contexts of rice production and their associated pest injuries. Rice pests could be classified into two broad research priority-setting categories with respect to simulated yield losses and management efficiencies. One group, including weeds, sheath blight, and brown spot, consists of pests for which effective pest management tools need to be developed. The second group consists of leaf blast, neck blast, bacterial leaf blight, and brown plant-hoppers, for which the efficiency of current management methods is to be maintained. Simulated yield losses in future production situations indicated that a new type of rice plant with high-harvest index and high-biomass production ("New Plant Type") was more vulnerable to pests than hybrid rice. Simulations also indicated that the impact of deployment of host resistance (e.g., through genetic engineering) was much larger when targeted against sheath blight than when targeted against stem borers. Simulated yield losses for combinations of production situations and injury profiles that dominate current lowland rice production in tropical Asia ranged from 140 to 230 g m(-2). For these combinations, the simulated efficiency of current pest management methods, expressed in terms of relative yield gains, ranged from 0.38 to 0.74. Overall, the analyses indicated that 120 to 200 x 10(6) tons of grain yield are lost yearly to pests over the 87 x 10(6) ha of lowland rice in tropical Asia. This also amounts to the potential gain that future pest management strategies could achieve, if deployed. 相似文献
5.
由稻瘟菌侵染引起的稻瘟病是威胁水稻安全生产最严重的真菌病害之一。鉴定克隆水稻抗稻瘟病基因, 系统深入研究稻瘟菌与水稻的相互作用, 揭示水稻的抗病机制, 进而创制推广抗稻瘟病新材料, 对确保粮食安全具有重要意义。本文总结了近10年来稻瘟病抗病基因和感病基因的鉴定、分子机理解析和应用等进展, 总结归纳了抗病基因聚合、分子设计育种、感病基因编辑、抗病基因的病原诱导表达等抗病育种主要策略。最后提出充分利用种质资源, 利用新技术挖掘新基因及创制新材料, 深入研究叶瘟和穗瘟抗病机制差异等是稻瘟病抗病育种下一步重点研究方向和新挑战。 相似文献
6.
F. O. Aderungboye 《国际虫害防治杂志》2013,59(3):305-326
Abstract Thirty two diseases and disorders affecting the oil palm in Africa, Southeast Asia and South America are described with their distribution, economic importance, etiology and control. Of these, nine diseases are considered to be of major economic importance, 19 are of minor importance, and four are due to nutrient deficiencies. The major diseases causing serious economic losses are freckle (Cercospora elaeidis), blast (Pythium splendens and Rhizoctonia lamellifera), vascular wilt (Fusarium oxysporum f. sp. elaeidis). Ganoderma trunk rot (Ganoderma spp.) and Armillaria trunk rot (Armillariella mellea) in Africa; Ganoderma trunk rot, Corticium leaf rot (Corticium solani). Marasmius bunch rot (Marasmius palmivora) in S.E. Asia; sudden wilt and spear rot in S. America. Some of the diseases and disorders of minor economic importance recorded in these areas are anthracnose (Botryodiplodia palmarum, Melanconium sp. and Clomerella cingulata), dry basal rot (Ceratocystis paradoxic), patch yellows (Fusarium oxysporum), crown disease, Cylindrocladium leaf spot (Cylindrocladium macrosporum), algal spot (Cephaleuros virescens), bronze streak, ring spot and little leaf in Africa; Curvularia leaf blight (Curvularia eragrostidis), Leptosphaeria leaf spot (Pestalotiopsis spp.) infectious chlorosis, upper stem rot (Phellinus noxius), stem wet rot, charcoal base rot in S.E. Asia and Leptosphaeria leaf spot and coconut wilt disease in S. America. Little is known, however, about the disease problems in the smaller but rapidly expanding oil palm growing areas of Thailand, Papua New Guinea, India and Sri Lanka. Infectious chlorosis, bronze streak and ring spot have a suspected virus etiology; little leaf, spear rot and stem wet rot are attributed to bacteria and leaf chlorosis, mid-crown yellowing, orange frond and hook leaf to nutrient deficiencies. The etiology of some minor disorders including brown germ, crown disease and several miscellaneous abnormalities is unknown. Effective control measures, based on the application of various chemicals, have been devised for the leaf diseases but other than precautionary cultural operations, there are no such effective and practical control measures for the root and stem diseases. For this latter group of diseases field transplanting or resistant or tolerant varieties seems to be the best method of control. Seeds selected for tolerance to vascular wilt are being produced on a commercial scale at the Nigerian Institute for Oil Palm Research, Institut de Recherches pour les Huiles et Oleagineux in Ivory Coast and the Unilever Plantations in Cameroun Republic. These efforts need to be supplemented by breeding for resistance to the other major diseases. 相似文献
7.
本文阐述了水稻叶鞘腐败病病原菌Sarocladium oryzae,在水稻各生育期和植株不同部位的叶鞘上之致病性以及由此产生的各种症状。该病原菌不仅在水稻各生育期发生危害,还能侵害叶鞘、谷粒、叶片中脉等。水稻剑叶叶鞘受害,常呈现为典型叶鞘腐败病病斑以及"紫鞘"或"紫鞘黄叶"症状。病谷常引起秧苗发病。发病的最适温度为30℃、湿度为70%(RH)。但发病对温湿度要求并不甚严格。适当的氮、磷、钾配比和适量施用能提高植株的抗病性,氮肥过多或缺乏均会加剧病害的发生与危害。品种的抗病性有着明显差异,但与水稻类型无关。以病原菌分生孢子液对21个常见杂草和野生稻接种,其中属于禾本科的15个种可引起发病。经田间调查,该病原菌也在自然条件下侵染若干禾本科杂草。 相似文献
8.
稻瘟病菌Magnaporthe oryzae严重威胁水稻的产量与质量,明确稻瘟病菌与水稻互作过程及机理,对防治稻瘟病具有重要意义。本研究利用稻瘟病菌常用致病菌株GUY11和ZB25,构建了绿色荧光蛋白GFP的过量表达菌株,并通过荧光显微观察菌株侵染寄主水稻过程中侵染结构的形成与发育,包括孢子萌发、附着胞形成、侵染钉形成、侵染菌丝增殖、坏死斑形成及产孢。另外,通过比较过量表达菌株对稻瘟病高抗水稻和易感水稻的侵染过程,发现侵染过程的差异主要集中于侵染钉的穿透和侵染菌丝的定殖。本研究为分析稻瘟病菌对寄主水稻的定殖规律提供了一种有效工具。 相似文献
9.
离体水稻叶片划伤接种鉴定稻瘟菌的致病型 总被引：1，自引：0，他引：1
抗瘟品种的培育和抗瘟基因布局需要快速、准确、大规模地定性水稻抗源及其后代的抗瘟基因型和稻瘟菌致病型。为此, 本研究建立了水稻离体叶片划伤接种方法。该方法依据主效抗瘟基因抵抗稻瘟菌在寄主体内扩展的特点, 通过针刺在水稻叶片上造成伤口, 避免了寄主侵入抗性的干扰, 从而有利于抗扩展性的定性鉴定。作者利用活体喷雾接种、叶片无划伤接种和本研究建立的离体叶片划伤接种等3种接种方法, 在秧苗4~6叶龄期, 对菌株12-DG-68在24个水稻抗瘟单基因系上的致病反应进行了测定, 结果显示：叶片划伤接种的检测结果稳定、一致; 而叶片无划伤接种和活体喷雾接种的检测结果假抗性比例分别为12.5%和4.2%, 不同叶龄期的叶片间反应型不一致率达7%。此外, 离体叶片划伤接种还可利用菌丝块接种, 以鉴定分生孢子产量低的菌株的致病型。因此, 水稻叶片划伤接种是一种准确、稳定和方便的稻瘟菌接种方法, 可用于大规模定性测定水稻抗源及其后代的抗瘟基因型和稻瘟菌的致病型。 相似文献
10.
水稻褐(紫)鞘病因之探讨 总被引：1，自引：0，他引：1
本文对褐(紫)鞘、鞘腐两种症状的诱发因子进行了描述。采用不同的接种方法,将不同来源的菌株在常规的水稻品种上接种,均可引起褐(紫)鞘和鞘腐二种症状,它们出现的频率随接种方法、品种和菌株的不同而异。作者认为把褐(紫)鞘症状看作为一种新的病害是不能成立的,它只能是水稻叶鞘腐败病的另一种症状。 相似文献
11.
贵州六盘水市猕猴桃病害调查及病原鉴定 总被引：1，自引：0，他引：1
针对2014年以来六盘水市猕猴桃病害日益严重的问题,分别于2015年10月、2016年4月及8月对六盘水市共12个乡镇26个代表性猕猴桃栽培园区病害进行了调查。采集了大量典型病害样本,综合生物学特性、分子鉴定及致病力测试对分离得到的病原菌进行鉴定。结果表明,六盘水市猕猴桃夏季和秋冬季病害主要为细菌性溃疡病和真菌性软腐病、灰斑病、褐斑病,其次是炭疽病和黑斑病,春季部分园区有细菌性溃疡病,真菌病害相对较轻。本文研究结果为六盘水市猕猴桃病害的预测预报及综合防治提供了理论依据。 相似文献
12.
甘肃玉米主要病害发生动态调查 总被引：16，自引：0，他引：16
为了掌握甘肃玉米病害的发生动态,明确主要病害的流行趋势,采用随机抽查法调查了甘肃庆阳、平凉、天水、陇南、定西、武威和张掖7个市/地区的玉米病害类群。结果表明,普通锈病、红叶病和穗腐病普遍发生并较严重,在7个市/地区的平均病株率分别为81.6%、80.6%和77.3%;大斑病、纹枯病、交链孢叶斑病、茎腐病、小斑病、瘤黑粉病和鞘腐病局部发生较重,在7个市/地区平均病株率分别为83.3%、44.9%、29.1%、27.5%、25.6%、14.4%和8.3%,矮花叶病和丝黑穗病普遍发生但发病较轻,在7个市/地区病株率分别为3.1%和1.1%,但矮花叶病在旱作区平凉市依然严重,丝黑穗病在武威市和张掖市的玉米制种田发病率依然较高。调查表明,甘肃玉米叶部病害、穗腐病和茎腐病有加重趋势,今后应该加强多病害抗性品种选育和防治用化学药剂的筛选研究。 相似文献
13.
禾谷丝核菌(Rhizoctonia cerealis)是引起我国小麦纹枯病的主要致病菌。为了建立高效稳定的禾谷丝核菌遗传转化体系,本试验比较研究了不同细胞壁降解酶、酶液浓度、酶处理温度和时间等因素对禾谷丝核菌原生质体制备的影响,利用正交设计试验优化了原生质体再生条件。结果表明,液体培养6d的菌丝,采用15mg/mL溶壁酶+10mg/mL蜗牛酶组成的混合酶液,30℃下酶解4h,可以获得较高的原生质体释放量,可达到3.0×106个/mL;禾谷丝核菌原生质体再生的最佳条件是以SuTC缓冲液作为渗透压稳定剂悬浮原生质体,采用单层混菌法接种于TB3再生培养基,原生质体再生率可达到58.6%。禾谷丝核菌原生质体制备和原生质体再生条件的优化,为深入研究禾谷丝核菌生长发育的分子遗传学基础和进一步探索小麦纹枯病的致病机理奠定了基础。 相似文献
14.
本文对上高县2014年早稻纹枯病、稻瘟病、二化螟、稻纵卷叶螟和稻飞虱这几类水稻主要病虫害在防治与不防治条件下进行了田间试验对比,对不同处理病虫情况及产量情况进行调查,对防治效益进行了评估。结果表明,完全不防治产量损失最大,单一病虫害中纹枯病损失最大,其次是稻纵卷叶螟、稻飞虱、二化螟和稻瘟病;完全不防治的效益损失最大,单一病虫害中纹枯病损失效益最大,其次是稻纵卷叶螟、稻飞虱、二化螟和稻瘟病。2014年上半年雨水多,湿度大,造成纹枯病重发生,稻纵卷叶螟和稻飞虱中等发生,二化螟和稻瘟病轻发生。 相似文献
15.
Richard Gavin Kotze Bridget Genevieve Crampton Quenton Kritzinger 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(2):295-311
Rice production is currently expanding from the south-eastern regions of Australia into northern Australia where indigenous species of wild rice occur widely. A survey of fungal diseases on wild (Oryza australiensis, Oryza spp.) and cultivated rice (Oryza sativa) in North Queensland, Australia, in May 2014 revealed a diverse range of fungal genera species, including important pathogens of cultivated rice. Whilst a single isolate of Magnaporthe oryzae (causal agent of rice blast) was obtained from wild rice, Bipolaris oryzae (causal agent of brown spot) was the predominant pathogen detected under North Queensland conditions. For the first time for Australia, we report Rhizoctonia oryzae-sativae (causal agent of aggregate sheath spot) occurring on wild rice. Other pathogens detected on wild rice included Curvularia lunata, Cochliobolus intermedius, Cochliobolus geniculatus, and Fusarium equiseti present in the majority of wild rice samples. Nearby cultivated rice fields harboured additional pathogens not found in wild rice including Fusarium graminearum, Leptosphaeria spegazzinii and Cochliobolus lunatus, causing scab disease, glume blight and leaf blight, respectively. We also confirmed that Bipolaris oryzae from wild rice can infect cultivated rice. This study highlights the importance of wild rice species as alternative hosts harbouring pathogens of cultivated rice and the likely disease threats to expansion of cultivated rice into the same region(s) where wild rice is endemic. 相似文献
16.
抗感品种混植对水稻主要病害的效应 总被引：15，自引：0，他引：15
1986-1988年利用抗感品种混植对水稻主要病害的效应进行了研究。结果表明:(1)对稻瘟病抑制作用显著,尤以对叶瘟效果最好(F=46.55,P<0.01)。与应发病值相比,其相对抑制效果:病叶率减少74.23%,病情指数降低85.30%。单植的病害日侵染速率(r)比混植高一倍以上。病情严重度与组合内抗感比例密切相关(r=0.951··)且呈幂函数关系:?=3.3918×7.4446x。(2)对稻纹枯病和稻白叶枯病均有一定效应,但不如稻瘟病显著。文中还对混植机理及存在问题进行了探讨。 相似文献
17.
In 1987 a new disease, called pseudostem rot, was observed on 3–5-month-old banana plants(Musa sp.) cv. ’Robusta’. The pathogen was isolated in pure culture and identified asCorticium rolfsii (Sacc.) Curzi, teleomorph ofSclerotium rolfsii Sacc. The teleomorphic stage of the fungus was observed inside the pseudostem sheath. The pathogen produced leaf spot diseases (by basidiospores) on 16 tested host plants from various families. 相似文献
18.
Wiwiek Harsonowati Rika Indri Astuti Aris Tri Wahyudi 《Journal of General Plant Pathology》2017,83(2):98-108
Fungal leaf blast, caused by Pyricularia oryzae, is a devastating disease of rice plants that annually causes severe production losses worldwide and is one of the top 10 fungal diseases that threaten global food security. Thus, a reliable control strategy against this disease is essential. In this study, the antagonistic activity of indigenous phyllosphere actinomycetes was elucidated against P. oryzae in vitro and in planta to develop an efficient, effective and environmental friendly approach to protect rice plants against P. oryzae. Of 75 isolates of actinomycetes isolated from the rice phyllosphere, 18 isolates inhibited P. oryzae by >45%. According to analysis of their 16 S rRNA gene sequences, the majority of the 18 isolates belonged to Streptomyces genera; others were identified as belonging to Saccharothrix, Gordonia, or Lentzea. Isolates that potentially produced a bioactive compound(s) were identified among the 18 isolates: 17 isolates (94.44%) had a domain marker for nonribosomal peptide synthetase (NRPS) gene and 12 (66.67%) had type-I polyketide synthase (PKS) gene in their corresponding genome. Interestingly, isolates JSN1.9, SKB2.14, and SKB2.3 suppressed disease suppression by approximately 88%. To our knowledge, this is the first report on the application of rice-phyllosphere actinomycetes producing bioactive compounds to control leaf blast disease in Indonesia. Thus, these findings have escalated the potential application of phyllosphere actinomycetes as a supreme biocontrol agent against fungal leaf blast disease. 相似文献
19.
水稻细菌性叶鞘褐腐病研究 总被引：2，自引：1，他引：2
从浙江嘉兴市和余杭市的晚稻褐腐叶鞘及谷粒的156份样本中分离出363个荧光细菌，经菌落形态和致病性测定后获得19个致病菌株，从中选出10个进行细菌学和Biolog鉴定，并与6个标准菌株比较，结果证实，这种水稻叶鞘褐腐病是由Pseudomonas fusouaginae引起，种子能带菌传病。 相似文献
20.
中国苹果病害发生与分布现状调查 总被引：3，自引：0，他引：3
本研究于2010-2012年在我国18个省(市、自治区)的1 100个苹果园采用隔行踏查法进行了实地调查。调查内容包括果园面积、品种名称、树龄结构以及各种病害发生情况。调查结果表明,3年间在我国苹果主产区共发现病害50种,其中包括新发现的2种病害:丝核菌叶枯病和炭疽菌叶枯病。通过分析确定了各种病害的严重度,明确了腐烂病、轮纹病、褐斑病和斑点落叶病4种主要病害及苹果锈病等8种中度发生病害的发生程度及区域分布,为各苹果主产省开展病害防控提供了理论依据。 相似文献