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1.
水稻稻粒黑粉病主要为害水稻不育系,是限制我国南方杂交水稻制繁种产量和质量的主要病害因素。为挖掘抗稻粒黑粉病的水稻不育系品种,提供具有抗稻粒黑粉病育种价值的水稻不育系材料,本研究于2014-2016年,采用田间接种稻粒黑粉病菌的方法,对四川、湖北、福建的78个水稻不育系品种进行了稻粒黑粉病菌抽穗期抗性评价。连续3年接种稻粒黑粉病菌试验表明,共有4个水稻不育系品种对稻粒黑粉病表现中抗及以上抗性,大部分为感病品种,其中4766A接种稻粒黑粉病菌后未发病,对稻粒黑粉病表现稳定高抗,为我国首次报道的高抗稻粒黑粉病水稻品种。 相似文献
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在相同条件下,从稻田直接收集的病粒中的稻粒黑粉病菌厚垣孢子不能萌发,而取之于仓库中的孢子能萌发。为探明其制约因素,对该病菌进行了光照和浸水时间试验。研究结果表明:稻粒黑粉病菌冬孢子形成后,必须经光照射后,方可进入休眠期;度过5~6个月休眠期的冬孢子,必须浸水48h以上才开始复苏;复苏后的冬孢子必须在光照条件下才能萌发。未完成后熟作用的冬孢子和完成后熟但尚未复苏的冬孢子即使在光照条件下也不能萌发。即稻粒黑粉病菌冬孢子必须经历后熟、休眠、复苏三个阶段后,在适宜的光照与温湿条件下,方可萌发。光照对其冬孢子具有双重作用,促使后熟进入休眠和刺激萌发。 相似文献
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籼型杂交水稻对稻曲病的田间抗性差异 总被引:2,自引:0,他引:2
为了解不同水稻品种在田间的抗性差异及其与农艺性状的相互关系,在相同的土壤环境和栽培条件下,利用稻曲病菌诱发接种鉴定,对56个籼型杂交水稻进行田间抗性差异比较,初步探讨了抽穗期和农艺性状与品种田间抗性的关系.结果表明,不同水稻品种对稻曲病田间抗性存在显著差异,病穗率为0.43%~33.04%,病情指数为0.05~16.14;不同抽穗期的品种稻曲病发病率不同,同一抽穗期的品种对稻曲病的抗性亦表现出明显差异;水稻株高与品种抗性之间呈正相关,相关系数为026(P<0.05);水稻分蘖率、有效穗数、剑叶性状等与品种的田间抗性有一定相关性,但差异不显著(P>0.05);水稻株叶形态和叶色与品种田间抗性没有直接相关性. 相似文献
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D. Shtienberg Miriam Zilberstaine D. Oppenheim Z. Herzog Shulamit Manulis H. Shwartz G. Kritzman 《Phytoparasitica》2001,29(2):143-154
The efficacy of oxolinic acid (at 200 and 300 μg a.i./l) and of several antibiotic compounds (streptomycin sulfate at 100 μg a.i./l, glycocide B at 700 μg a.i./l, kasugamycin at 80 μg a.i./l and gentamicin sulfate at 30 and 60 μg a.i./l) againstErwinia amylovora, the causal agent of fire blight in pears, was evaluated in 43 orchard experiments in 1997–2000 in Israel. In addition to
the above orchard experiments, the efficacy of the bactericides was tested in live experiments with artificial inoculation.
Natural fire blight symptoms were observed in 16 of the 43 experiments; in 13 of them, disease intensity and its distribution
among the experimental plots provided a basis for data analysis, leading to reliable conclusions concerning the efficacy of
the tested bactericides. Oxolinic acid at 300 μg a.i./l was highly effective againstE. amylovora and reduced disease severity significantly in all experiments, as compared with the untreated plots; however, a concentration
of 200 μg a.i./l was not effective in some cases. Among the tested antibiotics, only gentamicin sulfate was as effective as oxolinic acid.
Results of the artificial inoculation experiments corroborated those obtained in the naturally infected orchards. The pre-infection
activity of oxolinic acid was determined on blossom clusters that were sprayed with the bactericide before inoculation. Control
efficacy on blossom clusters sprayed 1–4 days before inoculation ranged from 68% to 80%, a level which did not differ significantly
from that observed on blossom clusters sprayed on the day of inoculation (80% control). The postinfection activity of oxolinic
acid was determined on blossom clusters that were sprayed with the compound after inoculation. Oxolinic acid was as effective
when applied 1 or 2 days after inoculation as when it was applied on the day of inoculation; however, application of the bactericide
3 days after inoculation no longer resulted in significant disease suppression. Oxolinic acid has been used commercially in
Israel since 1998 with appreciable success.
Contribution No. 533-00 from the Agricultural Research Organization 相似文献
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J. Fan X.‐Y. Guo F. Huang Y. Li Y.‐F. Liu L. Li Y.‐J. Xu J.‐Q. Zhao H. Xiong J.‐J. Yu W. Wang 《Plant pathology》2014,63(4):937-945
Ustilaginoidea virens (Uv), the causative agent of rice false smut disease, infects developing rice spikelets at the booting stage, and transforms individual grains of the panicle into smut balls. Epidemics of the disease occur when the rice booting and heading stages coincide with rainy days. Using a green fluorescent protein (GFP)‐labelled Uv isolate that can form false smut balls on rice panicles, it was found that under high humidity and free water conditions the Uv isolate could colonize leaves of plants belonging to various families including the Poaceae (Oryza sativa, Echinochloa crusgalli, Digitaria sanguinalis and Leptochloa chinensis), the Brassicaceae (Arabidopsis thaliana) and the Solanaceae (Nicotiana benthamiana) without symptoms. Over several days, some conidia could germinate on the leaves of these plants and in water on the surface of Parafilm and cellophane, form hyphae and differentiate conidiophores to generate a large number of secondary conidia, while other conidia were able to directly produce secondary conidia. Conversely, in the absence of water some conidia could either bud to form new conidia or were converted into chlamydospores. These data indicate that Uv is one of a few fungal pathogens reported to have epiphytic characteristics. The rapid generation of a large number of spores on biotic and abiotic surfaces greatly increases the inoculum that can infect rice spikelets, resulting in the occurrence of rice false smut disease epidemics. These findings are important in the development of disease control strategies. 相似文献
9.
D. M. De Costa S. S. T. Samarasinghe H. R. D. Dias D. M. N. Dissanayake 《Phytoparasitica》2008,36(1):52-65
Epiphytic microorganisms on the phyllosphere of traditional and high-yielding rice varieties were isolated from different
agroecological zones of Sri Lanka and screened for theirin vitro andin vivo antagonism againstRhizoctonia solani Kühn AG-1 1A, the sheath blight pathogen of rice. Among a total of 196 bacterial and 91 fungal isolates, 12 bacterial and
two fungal isolates which showed more than 50% growth inhibition ofR. solani were tested for theirin vivo antagonism. Among the 14 antagonists tested, six bacterial and one fungal isolate substantially reduced the incidence of
sheath blight (by more than 82%) and severity (by more than 92%) of the rice varieties BG94-1 and IR8 grown in a pot experiment
under open field conditions. Using five antagonists that showed the bestin vitro antagonism, a pot experiment was conducted to determine whether the presence of indigenous microflora on the rice sheath
had any effect on the effectiveness of antagonism. Three isolates (B4, GbB5 and HMWB4) controlled sheath blight incidence
and severity equally well in the presence and absence of indigenous microflora. Two isolates (BG352B1 and BG300B1) were more
effective when they were introduced into the rice sheath without indigenous microflora. Among the effective antagonists determined
by the pot experiment, isolates B4, B16, BG94-1B5, GbB5, HMWB4 and BG379-F2 were tested under field conditions for two consecutive
growing seasons. Under field conditions, severity of rice sheath blight was significantly reduced by the application of all
the tested antagonists as a spray on rice sheath at a concentration of 108 cfu ml−1, starting 3 days after the development of symptoms and continuing for three applications at 10-day intervals. Antagonistic
performances were consistent in the two seasons under field conditions andB. megatarium A (isolate B16) andAspergillus niger (isolate BG379-F2) performed as the most effective antagonists in both seasons. When disease severity was quantified as percentage
sheath area covered by the disease lesions, the respective reductions in disease severity were greater than 50% and 61% byB. megaterium A (isolate B16) andAspergillus niger (isolate BG379-F2), respectively, in both seasons.
http://www.phytoparasitica.org posting Jan. 10, 2008. 相似文献
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为进一步明确安徽省稻曲病发生关键期, 探索稻曲病气象等级预报方法, 以满足对该病害气象等级预报的服务需求?本文以安徽省池州市为例, 利用1995年-2018年一季稻稻曲病观测数据和同期气象资料, 通过相关分析确定稻曲病发生关键期?根据稻曲病大发生对适温高湿环境的需求及不同降水等级和温度对稻曲病发生程度的影响不同, 以稻曲病发生关键期降水日数为基础, 引入雨量系数和温度系数, 形成稻曲病发生综合气象条件指数, 通过最优曲线回归分析, 建立稻曲病预报模型?结果表明, 7月下旬至8月中旬是池州市一季稻稻曲病发生关键期; 综合气象条件指数与稻曲病病穗率相关性明显高于降水日数与病穗率相关性; 预报模型回代检验准确率为81.0%, 2016年-2018年模型预测结果均与实际情况相吻合, 由于样本中轻发生和大发生年份较少, 对轻发生和大发生预报的准确性需在样本丰富条件下进一步验证?模型在业务应用中, 可结合CFSv2模式逐日降水和气温预报产品, 提前10~30 d开展稻曲病气象等级预报, 对做好稻曲病的防治工作具有重要参考价值? 相似文献
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D. Shtienberg D. Oppenheim Z. Herzog Miriam Zilberstaine G. Kritzman 《Phytoparasitica》2000,28(4):361-374
The pear production area in Israel is 1500 ha, most of which(ca 1200 ha) is located in the northern part of the country. Fire blight (caused by the bacteriumErwinia amylovora (Burrill) Winslowet al.) was first observed in Israel in that region (in 1985) and the disease has prevailed there since then. In a comprehensive
survey conducted in Israel in 1996–1999, data were collected and observations were made yearly in one-third to one-half of
the pear production area. The aim was to document the prevalence and intensity of fire blight in commercial orchards and to
use the data to evaluate the efficacy of management measures employed for its suppression. Regionwise, a severe fire blight
epidemic developed in 1996, moderate epidemics developed in 1998 and 1999, and a mild epidemic developed in 1997. The intensity
of fire blight in the preceding season in a specific orchard was more influential on current season severity in a season with
a mild epidemic than in a season with a moderate epidemic. Analysis of disease onset records and weather data revealed that
only a few (1– 3) infection episodes occurred in individual orchards each year. Comparison of fire blight intensity in orchard-plots
treated before green tip with copper hydroxide with nontreated plots revealed that the treatment had no effect on disease
intensity during bloom. The efficacy of bactericide sprays applied during bloom was not related to the number of sprays applied
but to the timing of spraying. Adequate control was achieved in orchard-plots sprayed soon before or after the occurrence
of infection episodes.
Contribution no. 508/00 from the Inst. of Plant Protection, ARO, Bet Dagan, Israel. 相似文献
12.
Graft unions of nursery stock of grapevine (Vitis vinifera L.) collected in Japan yielded pathogenic and nonpathogenic strains of Agrobacterium. On the basis of classical diagnostic tests, a sequence analysis, and a multiplex polymerase chain reaction method previously
reported, the pathogenic strain was identified as Agrobacterium tumefaciens biovar 3, whereas the nonpathogenic strains were assigned to Agrobacterium radiobacter biovar 3. Stems of tomato (Lycopersicon esculentum Mill.) seedlings were inoculated with both A. tumefaciens biovar 3 strain G-Ag-27 as a pathogen and one of the control strains isolated from grapevine or A. radiobacter biovar 2 strain K84 as competitors to assay the suppression of gall formation caused by the pathogen. In a test with a 1 : 1
pathogen/nonpathogen cell ratio, all A. radiobacter biovar 3 strains reduced gall incidence and size compared to that of the positive control inoculated only with the pathogen.
Strain VAR03-1 was especially effective in reducing the incidence of gall formation on grapevine and reduced gall size by
84%–100% of those on the positive control. Many tested nonpathogenic biovar 3 strains were bacteriocinogenic, causing an inhibition
zone against A. tumefaciens biovar 3 strains on YMA medium. Strain VAR03-1 was the most effective against indicator strains and appears to be a promising
agent for controlling crown gall of grapevine. 相似文献
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Serratia marcescens strain B2 is an antagonistic bacterium that produces the red-pigmented antibiotic prodigiosin and suppresses rice sheath blight caused by Rhizoctonia solani AG-1 IA. Rice sheath blight disease was suppressed when plants were inoculated with this bacterium an hour before pathogen inoculation but not when plants were treated 4 weeks before pathogen inoculation. In both cases the bacteria were detected in the rice rhizosphere 4 weeks after inoculation. Bacteria isolated from the rice plant and rhizosphere inhibited biosynthesis of prodigiosin in S. marcescens strain B2. We suggest that bacteria isolated from rice plants and rhizospheres mediate the suppression of antibiotic production of biological control agents and that such suppression is common under field conditions. 相似文献
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Y.‐L. Zhou X.‐W. Xie F. Zhang S. Wang X.‐Z. Liu L.‐H. Zhu J.‐L. Xu Y.‐M. Gao Z.‐K. Li 《Plant pathology》2014,63(2):365-372
False smut, caused by Ustilaginoidea virens, is a rice disease of increasing importance worldwide, with no source of high‐level resistance in the existing rice germplasm. To facilitate breeding varieties with good levels of field resistance to false smut, quantitative resistance loci (QRL) were identified using 213 introgression lines (ILs) from a cross between Teqing (recipient) and Lemont (donor) evaluated using natural infection at two hotspots of false smut in northeast China. Ten QRL affecting percentages of diseased hills, diseased panicles and diseased spikelets were detected and mapped to rice chromosomes 2, 3, 4, 6, 8, 10, 11 and 12. The Lemont alleles at all QRL increased false smut resistance. Four QRL (qFSR‐6‐7, qFSR‐10‐5, qFSR‐10‐2 and qFSR‐11‐2) had relatively larger and consistent effects across the two testing sites. Promising resistant ILs were identified, most of which had multiple QRL, suggesting that pyramiding multiple QRL by marker‐assisted selection would be an effective strategy for improving rice resistance to false smut. The identified QRL and their linked DNA markers will facilitate this breeding effort in the future. 相似文献
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Ladhalakshmi Duraisamy Srinivas Prasad Madamsetty Prakasam Vellaichamy Krishnaveni Donempudi Sailaja Banda Ram Singh 《国际虫害防治杂志》2019,65(2):177-185
False smut disease of rice caused by the fungus Ustilaginoidea virens, has become a serious production constraint in various rice-growing regions of India. Analysis of rice false smut disease survey data of last 24 years revealed significant changes in the intensity of the disease in various rice-growing regions of India over the years. We evaluated three fungicide formulations viz., trifloxystrobin-tebuconazole (TT) combination (0.04%), kresoxim methyl (KM) (0.1%) and propiconazole (PC) (0.1%) for their effectiveness against false smut disease of rice. Under in vitro condition, TT and PC completely inhibited the fungal growth while KM inhibited the growth by 80%. We evaluated the efficacy of these chemicals in a multi-location trial in 3 hot spot locations, consecutively for three years. A single fungicide spray was given in 3 different crop stages (booting, 50% panicle emergence and 100% panicle emergence). The results indicated that all the treatments significantly reduced the percentage of both infected panicles and spikelets in all the three locations. Both TT and PC were most effective in reducing the disease intensity and increasing the yield when applied either in booting or in 50% panicle emergence stage. 相似文献
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Kaoru Zenbayashi-Sawata Taketo Ashizawa Shinzo Koizumi 《Journal of General Plant Pathology》2005,71(6):395-401
The japonica rice (Oryza sativa) cultivar Chubu 32 has a high level of partial resistance to blast, which is mainly controlled by a dominant resistance gene
located on chromosome 11. The partial resistance to the rice blast fungus (Magnaporthe grisea) in Chubu 32 has isolate specificity; isolate IBOS8-1-1 is more aggressive on Chubu 32 than are other isolates. We hypothesized
that the gene-for-gene relationship fits this case of a partial resistance gene in Chubu 32 against the avirulence gene in
the pathogen. The partial resistance gene in Chubu 32 was mapped between DNA markers C1172 (and three other co-segregated
markers) and E2021 and was designated Pi34. In the 32 F3 lines from the cross between a chromosome segment substitution line (Pi34−) from Koshihikari/Kasalath and Chubu 32, the lines with high levels of partial resistance to the M. grisea isolate Y93-245c-2 corresponded to the presence of Pi34 estimated by graphic genotyping. This indicated that Pi34 has partial resistance to isolate Y93-245c-2 in compatible interactions. The 69 blast isolates from the F1 progeny produced by the cross between Y93-245c-2 and IBOS8-1-1 were tested for aggressiveness on Chubu 32 and rice cultivar
Koshihikari (Pi34−). The progeny segregated at a 1 : 1 ratio for strong to weak aggressiveness on Chubu 32. The results suggested that Y93-245c-2
has one gene encoding avirulence to Pi34 (AVRPi34), and IBOS8-1-1 is extremely aggressive on Chubu 32 because of the absence of AVRPi34. This is the first report of a gene-for-gene relationship between a fungal disease resistance gene associated with severity
of disease and pathogen aggressiveness. 相似文献
18.
Karl-Josef Mueller 《European journal of plant pathology / European Foundation for Plant Pathology》2006,116(2):145-153
Forty-two registered spring barley cultivars from the German official list were tested under natural infection conditions for susceptibility to loose smut (Ustilago tritici f.sp. hordei) during two test cycles at two locations. Only cv. Steffi was found to be resistant to the local loose smut population. Cultivar Sigrid showed lowest susceptibility because of flowering inside the leaf sheath. Less than 1% infection at all sites showed up in cvs Auriga, Jacinta and Hendrix. Twenty-one cultivars had an infection rate of less than 2%. Cultivar Danuta displayed the highest susceptibility with an average of 12.6%. Another 23 spring barley accessions with expected loose smut resistance were inoculated artificially with loose smut populations obtained from 11 locations in Germany and neighbouring countries. Only Jet with the resistance Un3/6, CDC Freedom with Un8, CIho9973 with quantitative resistance, as well as Lino and GangTuoQuingKeHao1 remained disease-free. In addition to these, another eight accessions in this test group are recommended to become part of a differential tester set to distinguish origins of loose smut. Statistical analysis showed that for scoring of cultivars more importance has to be given to the number of locations for infestation than to the number of test locations to determine the degree of attack. In view of the existing inspection limits for production of certified seed in European countries, the currently registered German barley cultivars put organic seed producers and breeders at high risk in respect to loose smut infection, if the number of generations for multiplication under organic farming increases. 相似文献
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Friederike Pferdmenges Mark Varrelmann 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(2):231-245
Beet necrotic yellow vein virus (BNYVV) is transmitted by Polymyxa betae to sugar beet, causing rhizomania disease. Resistance-breaking strains of BNYVV, overcoming single (Rz1) or double (e.g. Rz1
+
Rz2) major resistance genes in sugar beet have been observed in France and recently in the USA and Spain. To demonstrate if resistance-breaking
is dependent on inoculum density, the inoculum concentration of BNYVV and P. betae in soil samples where resistance-breaking had been observed was estimated using the most probable number (MPN) method. The
MPN-values obtained displayed highly significant differences with respect to the virus concentration in various soils and
did not correlate with the ability to overcome resistance. Virus quantification in susceptible plants demonstrated that soils
containing resistance-breaking isolates of BNYVV did not produce higher virus concentrations. The MPN assay was repeated with
Rz1
+
Rz2 partially-resistant sugar beets to see if the resistance-breaking is concentration-dependent. There was no correlation between
soil dilution and increased virus concentration in Rz1
+
Rz2 plants produced by BNYVV resistance-breaking strains. Determination of the absolute P. betae concentration by ELISA demonstrated that all resistance-breaking soil samples contained elevated concentrations. However,
the calculation of the proportion of viruliferous P. betae did not show a positive correlation with the resistance-breaking ability. Finally resistance-breaking was studied with susceptible,
Rz1 and Rz1
+ Rz2 genotypes and standardised rhizomania inoculum added to sterilised soil. Results from these experiments supported the
conclusion that resistance-breaking did not correlate with virus concentration or level of viruliferous P. betae in the soil. 相似文献