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为探明温度对梨树腐烂病菌生长、病斑扩展及产毒素水平的影响,采用常规生物学方法和高效液相色谱法,测定了该病菌强致病力菌株LXS240101在不同温度下的菌丝生长、病斑扩展及产毒素水平。结果表明:菌株LXS240101最适宜的生长温度为25~30℃;在5~35℃范围内,梨树离体枝条接种梨树腐烂病菌后均能发病并导致病斑扩展,25℃时病斑扩展速度最快,面积达4.45cm2,5℃和35℃时病斑扩展速度缓慢,面积不足0.3 cm2。该菌株在梨树树皮培养基中最适宜的产毒素温度为20℃,10~25℃条件下可产生5种毒素,而在其它温度下仅产生3~4种;接种该菌株的梨树离体枝条5℃条件下未检测到间苯三酚和对羟基苯甲酸,且毒素总量最低,其余温度下均可检测到5种毒素,最适宜的产毒素温度为10℃,毒素总量可达224.14μg/g干组织。 相似文献
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在田间设置方块圃和穴植圃,进行小麦白粉菌寄生适合度测定方法的研究。在方块圃测定单小种和混小种的流行速率;在穴植圃测定单小种和混小种的多项抗性指标,并计算了综合病指。通过相关分析表明,用流行速率、综合病指和抗性组分中的普遍率、严重度、产孢量推算的寄生适合度之间相关极显著,均可作为估计相对寄生适合度的代表性指标。 相似文献
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施氮量对水稻叶瘟菌侵染循环中主要组分的影响 总被引：7，自引：0，他引：7
在人工气候室内进行了施氮量对稻瘟侵染过程主要环节影响的定量试验。结果表明,施氮量对稻瘟菌侵染、病斑扩展及产孢均有不同程度的影响,其中,侵染几率所受影响最大,其次为病斑扩展及产孢,潜育期基本上不受影响。试验还发现,稻瘟侵染、产孢和病斑扩展各组分对氮量均有最适要求,当施氮量超出它们的最适范围后,将不再有利于各组分的发展。以上结果均用数学模型进行了描述,揭示了侵染循环各组分与施氮量间关系及警戒氮量在稻瘟流行学上的意义。 相似文献
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小麦慢白粉品种的抗性组分研究 总被引：2，自引：1，他引：1
2003~2004年度和2004~2005年度在田间测定了16个小麦品种(系)对小麦白粉菌E20菌株的抗性组分,包括潜育期、侵染几率、产孢量、病斑扩展和传染期。结果表明,小麦慢白粉品种(系)与高感对照品种相比,表现为潜育期长、侵染几率低、产孢量低、病斑扩展慢的特点,且这4个抗性组分与对照的差异都达到了显著和极显著水平,但慢白粉品种的传染期变化无一定规律。参试慢白粉品种的抗性组分参数与病情曲线下面积(AUDPC)的相关分析表明,潜育期与AUDPC呈负相关,但相关性不显著;产孢量和病斑扩展与AUDPC呈正相关,两年数据相关性均达到显著水平;侵染几率与AUDPC呈正相关,但2003-2004年度相关性不显著,而2004~2005年度相关性显著;传染期与AUDPC相关关系不明显。由此可见,在慢白粉品种的病害流行中起主要作用的是产孢量、病斑扩展,而侵染几率、潜育期和传染期作用相对较小。 相似文献
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为准确预测条锈菌流行小种在鄂西北地区的变异动态,本研究采用抗性组分法测定了CYR32、CYR33对当地主栽品种的寄生适合度。结果表明:决定鄂西北小麦条锈菌最重要的寄生适合度组分依次为条锈菌的侵染能力、扩展能力和产孢能力;建立了小麦条锈菌寄生适合度属性3个主成份的数学模型;从总体结果看CYR32、CYR33均表现较高相对寄生适合度,且CYR32略高于CYR33,但相比感病对照品种和外来品种,供试小种对当地主栽品种鄂麦352和襄麦55表现出较低的寄生适合度。 相似文献
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以12个全国大面积种植的小麦生产品种和1个高感品种为试材,利用抗性组分法研究了中国小麦条锈菌(Puccinia striiformis f.sp.tritici,Pst)4个主要流行小种条中32号、条中31号、水源11-14和水源11-4的寄生适合度。因子分析结果表明,病害量是度量条锈菌生理小种寄生适合度最重要的参数,其次是夏孢子生活力、产孢能力、产孢面积、产孢期,由此提出寄生适合度=(产孢量×侵染概率×夏孢子堆密度×夏孢子萌发率)/潜育期。研究还发现,条中32号的寄生适合度最高,致病性最强,与目前该小种为优势小种的事实相符;水源11-14的寄生适合度较高,有较大的发展潜力,在抗病育种中应予以高度重视。 相似文献
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粉红粘帚霉67-1菌株寄生核盘菌研究 总被引：5，自引：0，他引：5
用诱捕法从海南乐东县菜园土壤中获得一株对核盘菌菌核具有强寄生能力的粉红粘帚霉(Gliocladium roseum)菌株67-1,寄生频率为100%。该菌的PDA平板回接核盘菌菌核,一周后寄生率可达100%。对峙培养发现其对核盘菌有明显的抑菌带。保湿条件下,该菌孢子在24h内成功侵入核盘菌菌核。切片显微观察证明该菌能高效侵染菌核,造成组织溃解。寄生过程中菌核内蛋白组成发生明显变化。这一菌株在22~35℃均能很好生长,菌丝及产孢最适温度为24℃,产孢量大。认为这一菌株具有良好的菌核病生防应用潜力。 相似文献
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为了解宁夏南部山区马铃薯主栽品种对马铃薯晚疫病菌的抗病性情况,明确不同菌株的寄生适合度,采用离体叶片接种法,用4个马铃薯品种对采自宁夏南部山区的5个马铃薯晚疫病菌分离株进行了侵染率、病斑面积、产孢能力的测定和寄生适合度的计算。结果表明,‘克新18号’对供试的晚疫病菌分离株具有较高的抗病性,其次为‘中薯3号’和‘克新1号’,‘费乌瑞它’的抗病性最差;来源于固原原州区的分离株(GL2和GL7)寄生适合度较高,来源于泾源县的分离株(JZ)寄生适合度较弱。采自宁夏不同地区的晚疫病菌分离株对同一马铃薯品种的寄生适合度有较大差异,同一晚疫病菌株在不同马铃薯品种上的寄生适合度也有一定的差异,表明宁夏南部山区马铃薯晚疫病菌分离株存在一定的致病性分化。 相似文献
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列当是根寄生杂草,很难防除。菌株Br-1是从感病列当中分离出的对列当有较高防治效果的层出镰刀菌。为了提高菌株Br-1的产孢量,本研究通过单因素试验和正交设计试验对其培养基和发酵条件进行了优化。结果表明,菌株Br-1适宜的发酵培养基为葡萄糖1%,NH4NO_3 0.2%,KH_2PO_4 0.3%,Mg SO4·7H_2O0.1%;优化后的培养条件为:最初pH 5.0,培养温度24℃,装液量20%,振荡速度190 r/min,发酵时间6 d。较优化前的初始培养基和培养条件产孢量提高了257.5倍。在田间防治试验中菌株Br-1对弯管列当的防治效果最高可达67.2%。 相似文献
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中国小麦条锈菌主要流行菌系的寄生适合度研究 总被引：2，自引：0，他引：2
为了预测我国未来小麦条锈菌的优势种群,本研究采用抗性组分法测定了我国条锈菌主要流行菌系的寄生适合度。结果表明:决定我国小麦条锈菌最重要的寄生适合度属性为条锈菌的产孢能力(繁殖力),其次为条锈菌的侵染能力,再次为扩展能力;建立了小麦条锈菌寄生适合度属性3个主成份的数学模型;在供试的菌系中,Su11-4、Su11-14和CY32相对寄生适合度较高,已经成为我国目前小麦条锈菌的优势小种(类型);CY31由于其寄生适合度较低,出现频率逐年下降,已成为次要小种,感染"中四"苗期的新菌系T4类型,由于其寄生适合度低,也不会成为今后一个时期的流行小种。 相似文献
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为预测T4新菌系在我国未来小麦条锈菌的流行趋势,本研究以高感品种铭贤169为试材,以我国条锈菌5个主要流行小种（菌系）CYR29、CYR31、CYR32、CYR33、Su11-4为对照,采用主成分分析法测定了T4新菌系的寄生适合度。结果表明：在供试菌系范围内,决定其寄生适合度属性的3个主成分依次为条锈菌的侵染能力、扩展能力和产孢能力(繁殖力);通过建立数学模型计算供试菌系的侵染能力、扩展能力和产孢能力,结果表明：CYR33和CYR32相对寄生适合度较高,Su11-4的寄生适合度居中,CYR31及CYR29其寄生适合度较低,而感染“中四”苗期的新菌系T4,相对寄生适合度最低。结合该菌系对我国目前推广品种和后备品种致病性和毒性结果分析,该菌系在今后一段时间内不会成为我国小麦条锈菌的优势菌系。 相似文献
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用小麦离体叶段法,设置22、23、24、25和26℃共5个温度处理,对2009年采自四川、北京、甘肃、河南、河北、陕西和湖北七省（市）的小麦白粉菌标样分离获得的129个单孢堆菌株对温度的敏感性进行了测定。结果表明,供试的129个菌株平均ET50为22.49℃,其中ET50最高为24.48℃,最低为19.88℃,供试菌株中40.52%的ET50介于23℃和24℃之间,占参试菌株的近一半,7.63%的供试菌株ET50≥24℃。不同省（市）的病菌群体对温度的敏感性存在一定差异,且病菌群体对温度的敏感性差异与经纬度存在显著或极显著的负相关关系。研究结果获得了温度对此病害的终止阈值平均为26.65℃,且对温度相对不敏感菌株在较高温度下的潜育期较短、病害的严重度较高。不同敏感性菌株的频率分布结果表明,自然环境中病菌群体已受到温度的选择压力。 相似文献
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ABSTRACT The aggressiveness of 22 isolates of Phytophthora infestans collected from naturally infected potato plants in the Columbia Basin of Washington and Oregon was determined on detached potato leaflets at 18 degrees C in an incubator. Selected isolates were evaluated on whole plants in a greenhouse. Aggressiveness was measured by using the area under the lesion expansion curve (AULEC), incubation period, latent period, sporulation capacity, and lesion size on detached leaflets and the area under the disease progress curve and sporulation capacity on whole plants. The detached-leaflet assay was useful in that a large number of isolates were tested, several components of aggressiveness were studied, and significant differences were found among isolates. Significant variation for components of aggressiveness was found within and among isolates classified according to genotype. Significant interactions among isolates and cultivars were found for some components of aggressiveness, so results were pooled according to cultivar. On average, US-8 and US-11 isolates had higher AULEC scores, indicating aggressiveness higher than that of US-7, US-6, and US-1 genotypes. One US-8 genotype isolate had a higher standardized sporulation capacity than isolates of the other genotypes. US-6 genotype isolates were the least aggressive group, as indicated by low AULEC, sporulation capacity, and lesion size values. The replacement of the US-1 genotype by the US-8 genotype in the Columbia Basin may be partially explained by the increased aggressiveness of US-8 isolates. Additionally, potato growers may need to shorten intervals between fungicide applications and begin applications earlier. 相似文献
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Phenotype stability, fitness, and competitive ability of pyraclostrobin- and boscalid-resistant isolates of Botrytis cinerea from apple were investigated. Stability of resistance was determined after consecutive transfers on potato dextrose agar (PDA) or being cycled on apple fruit. In vitro fitness components mycelial growth, osmotic sensitivity, conidial germination, and sporulation were evaluated on agar media. Pathogenicity, virulence and sporulation on apple fruit were evaluated at both 20 and 0°C. Competition between fungicide-resistant and -sensitive isolates on apple fruit also was evaluated. Resistance to the two fungicides was retained at levels similar to that of the initial generation after 20 and 10 transfers on PDA and five and three disease cycles on apple fruit at 20 and 0°C, respectively. Great variability in individual fitness components tested was observed among isolates within the same phenotype groups either sensitive or resistant to the fungicides but, when compared as phenotype groups, there were no significant differences in the mean values of these fitness components between resistant and sensitive phenotypes except that the phenotype resistant only to boscalid produced fewer conidia in vitro than sensitive isolates. Resistant isolates were as pathogenic and virulent on apple fruit as sensitive isolates. There was no significant correlation between the values of individual fitness components tested and the level of resistance to pyraclostrobin or boscalid, except that virulence at 20°C positively correlated with the level of resistance to the two fungicides. The final frequency of pyraclostrobin-resistant individuals in the populations was significantly decreased compared with the initial generation and no boscalid-resistant individuals were detected after four disease cycles on apple fruit inoculated with a pair mixture of a dual-sensitive isolate and one isolate each of the three phenotypes resistant to pyraclostrobin, boscalid, or both. The results suggest that resistance of B. cinerea to pyraclostrobin and boscalid was stable in the absence of the fungicides and that resistance to the two fungicides did not significantly impair individual fitness components tested. However, both pyraclostrobin- and boscalid-resistant isolates exhibited competitive disadvantage over the dual-sensitive isolate on apple fruit. 相似文献
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为了解致病类型G22-83及流行小种CYR32和CYR33对四川省近年小麦生产品种和后备品种的寄生适合度,在田间分别将致病类型G22-83、流行小种CYR32和CYR33接种于四川省109个小麦品种(系),采用综合病情指数法测定3个供试菌株的相对寄生适合度。结果显示,致病类型G22-83、流行小种CYR32和CYR33的平均寄生适合度分别为0.1930、0.0560和0.0379,且前者显著高于后两者;流行小种CYR32和CYR33的平均相对寄生适合度有差异,但是差异不显著。致病类型G22-83、流行小种CYR32和CYR33在四川省109个小麦品种(系)上相对寄生适合度的中位数分别为0.0626、0.0000和0.0000,前者在四川省109个小麦品种(系)上相对寄生适合度的平均水平和波动程度均高于后两者。致病类型G22-83在四川省小麦生产品种和后备品种上的寄生适合度较高,在今后一段时间内可能成为该地区小麦条锈菌的优势菌系。 相似文献
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2008年我国部分麦区小麦白粉病菌群体对温度的敏感性 总被引：1，自引：1，他引：0
The sensitivity of 113 isolates of wheat powdery mildew (Blumeria graminis f. sp. tritici) sampled from 6 provinces or cities in 2008 to temperature was tested by detached leaf segment method with setting up 5 different temperatures indoor. The results showed the mean ET50 (which represents the temperature that is required to obtain 50% of the maximum effect) of all isolates tested was 23.02℃. ET50 values of 17.70% isolates were more than 24℃. The highest and the lowest ET50 of isolates were 25.22℃ and 19.42℃, respectively. There were a certain differences for isolates sensitivity to temperature among different provinces or cites. It was also found that when temperature increased during 22-26℃, the latent period of isolates prolonged, and the latent period of different isolates was different at the same temperature, too. These results will provide a reference for the oversummering division of wheat powdery mildew, as well as the effect of climate to the disease. 相似文献
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研究小麦白粉病菌群体对温度的敏感性及其与毒性的关系,可为气候变化背景下小麦白粉病的长期发生趋势预测和防治提供依据。本研究对2013年采自云南、四川、河南、北京和陕西五省（市）的小麦白粉菌标样进行分离纯化,获得90个单孢子堆分离物,采用小麦离体叶段法进行温度敏感性测定,并利用32个已知抗病基因品种（系）进行毒性测定,且对两者之间的相关性进行分析。结果表明,供试菌株ET50分布于19.78℃~25.15℃,平均ET50为23.22℃,其中73.34%的供试菌株ET50值介于22℃到24℃之间,小于22℃的菌株占10%,大于24℃的菌株占16.67%。利用Popgen1.32软件对5个省（市）小麦白粉病菌群体的毒性进行多样性分析,结果表明五省市小麦白粉菌群体毒性水平上的多样性指数 H 值为0.237 0,其中四川群体毒性多样性水平最高,Nei’s基因多样性指数 H 值为0.221 2,河南群体最低, H 值为0.197 5。小麦白粉菌群体对温度敏感性与毒性多样性相关性分析结果表明,ET50与毒性多样性（ H 和 I 值）间存在显著的负相关。 相似文献