首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
番茄晚疫病菌对甲霜灵、霜脲氰和烯酰吗啉的敏感性检测   总被引：5，自引：0，他引：5  
 【目的】研究广西番茄晚疫病菌对甲霜灵、霜脲氰和烯酰吗啉的敏感性,以期为该病的综合治理提供科学依据。【方法】用菌落生长直径法测定病菌对甲霜灵、霜脲氰和烯酰吗啉的敏感性,并用叶盘漂浮法加以比较。【结果】2000～2006年,从广西8个冬春植番茄区采集分离了239个菌株,测定结果表明,对甲霜灵表现为敏感型、中间型和抗性型的频率分别为42.26%、35.98%和23.53%,不同地区和年份的菌株对甲霜灵的敏感性差异很大。来自田林县、武宣县的菌株均为甲霜灵敏感性菌株,但在田阳县,抗甲霜灵菌株占优势,抗性频率高达51.35%,一些菌株的EC50值在500 µg•ml-1以上,抗性水平超过105倍。虽然霜脲氰在广西使用了近10年,烯酰吗啉也已应用了5～6年,但并未检测到番茄晚疫病菌对它们的敏感性下降的抗药性亚群体,病菌的敏感性接近正态分布,因此可以采用它们的平均EC50值（霜脲氰0.1647±0.0255 µg•ml-1,烯酰吗啉0.0970±0.0052 µg•ml-1）作为抗药性监测的敏感性基线。叶盘漂浮法测定结果与菌落生长直径法一致。【结论】广西田林县、武宣县和南宁市番茄晚疫病菌尚未出现抗甲霜灵菌株,仍可用甲霜灵来防治该病,而其它地区则应减少或不使用甲霜灵,改用霜脲氰或烯酰吗啉。  相似文献   

2.
The isolates of Phytophthora infestans on tomato in the Guangxi Zhuang Autonomous Region, China, were determined for the sensitivities to metalaxyl, cymoxanil and dimethomorph to give the basic information for integrating disease management. Sensitivities were tested by measuring the radial growth on agar medium amended with fungicide, compared with the floating-leaf-disk method. 239 isolates were collected from eight tomato growing areas during 2000-2006. The testing results indicated that the frequencies of sensitive, intermediate, and resistant isolates to metalaxyl were 42.26, 35.98, and 23.53%, respectively. Variations in sensitivities amongst isolates from different areas or different years were very high for metalaxyl. All isolates from Tianlin and Wuxuan were sensitive to metalaxyl, but the metalaxyl-resistant isolates predominated in Tianyang, with the frequency of 51.35%. The EC50 values of certain isolates from Tianyang were higher than 500 μg mL-1 and their resistance levels were over 100000 folds. Cymoxanil has been used for nearly 10 years in Guangxi, and dimethomorph has been used for 5-6 years. However, there was no decrease in sensitivity of P. infestans populations and the sensitivities of the pathogen were nearly normally distributed. Hence, their mean EC50 value [cymoxanil (0.1647±0.0255) μg mL-1, dimethomorph (0.0970±0.0052) μg mL-1] could be used as the baseline sensitivities for monitoring the field resistance development. The comparison with the floating-leaf-disk method indicates that both the techniques provided equivalent results. These studies suggested that metalaxyl can be continuously applied in Tianlin, Wuxuan, and Nanning due to the resistant isolates that have not been found, while for those areas with resistant isolate, the use of metalaxyl should be reduced or alternated, and cymoxanil or dimethomorph was recommended for controlling late blight disease of tomato.  相似文献   

3.
为明确致病疫霉菌甲霜灵抗性菌株对氟吗啉、嘧菌酯、吡唑醚菌酯、烯酰吗啉和霜脲氰的敏感性,采用菌丝生长速度法,并用叶盘漂浮法加以比较,测定了致病疫霉菌甲霜灵抗性菌株和敏感性菌株对供试杀菌剂的敏感性.试验结果表明,供试5种杀菌剂对致病疫霉菌甲霜灵抗性和敏感菌株的菌丝生长、孢子囊的形成都具有明显的抑制作用.对致病疫霉菌甲霜灵抗...  相似文献   

4.
With the bioguided fractionation of the ethanol extracts from the leaves of Momordica charantia, we obtained two most active compounds against the feeding of the diamondback moth, Plutella xylostella larvae. The antifeedant activity of momordicine Ⅰ and momordicine Ⅱ against the second and the third instar larvae of Plutella xylostella were tested using leaf discs of cabbage in the laboratory. The results showed that momordicin Ⅰ and momordicin Ⅱ had significant antifeedant activity on the larvae of P. xylostella, and momordicin Ⅱ was more active than momordicin Ⅰ. The concentrations for 50% antifeedant effects （AFC50） of momordicin Ⅱ against the second and the third instar larvae of P. xylostella were 76.69 and 116.24μg mL^-1, whereas that of momordicin I was 144.08 and 168.42μg mL^-1, respectively. In addition, momordicin Ⅰ and momordicin Ⅱ had significant inhibitive effect on the rate of weight gain and survival of P. xylostella larvae.  相似文献   

5.
Active oxygen quantum yield, insecticidal activities and stability of diphenylthiophene were studied for the first time. The results showed that maximum diphenylthiophene absorbency variety was 0.438 after irradiation for 280 min and that of α-terthienyl (α-T) was 0.480 after irradiation for 200 min with UV. LC50 values ofdiphenylthiophene and α-T against 3rd instar larvae of Aedes albopictus were 9.18 × 10-3 and 9.69 × 10-4 μg mL-1 when treated for 24 h, respectively. LC50 values of the two chemicals against the 3rd instar larvae of Plutella xylostella were 267.87 and 222.22 μg mL-1 when treated for 24 h, respectively. The half lives of diphenylthiophene and α-T in methanol were 113.62 and 10.65 h. Difference between quantum yield of diphenylthiophene and α-T was not significant and they all possessed high toxicity to Aedes albopictus and Plutella xylostella, but diphenylthiophene was more stable than α-T. It could be concluded that diphenylthiophene has overcome the deficiency of photoactivated insecticides which degraded quickly in the environment and could not be applied on the field. Diphenylthiophene could kill the insects and accelerate the degradation rate of triazophos. The benefits of diphenylthiophene can be further exploited and applied on the field.  相似文献   

6.
甘肃省马铃薯致病疫霉交配型组成及其对甲霜灵的抗药性   总被引：2，自引：0，他引：2  
为了明确甘肃省马铃薯致病疫霉交配型组成与对甲霜灵的抗药性,采用生长速率法对2007-2012年采集标样中分离到186株致病疫霉菌进行甲霜灵抗药性测定,利用对峙培养法对147株代表性菌株进行交配型测定。结果表明:甘肃省马铃薯致病疫霉交配型由A1、A2、A1A2交配型和自育型菌株组成,分别占被测菌株的61.20%、20.40%、2.10%、16.30%;186株致病疫霉中28.50%的菌株对甲霜灵表现敏感,15.60%表现中抗,55.90%表现高抗。甘肃省马铃薯致病疫霉交配型组成复杂,各采集地组成差异较大,对甲霜灵表现抗药性的菌株普遍存在各采集地。  相似文献   

7.
【目的】研究抗氟吡菌胺突变体对不同杀菌剂的交互抗性并评估马铃薯晚疫病菌对氟吡菌胺的抗性风险。【方法】通过紫外线照射菌丝体、紫外线照射孢子囊和药剂驯化的方法获得抗氟吡菌胺的马铃薯晚疫病菌突变体,计算突变体的突变频率,测定抗性突变体的抗性水平,研究突变体在无药条件下继代培养10代后抗性能否稳定遗传,测定突变体在RSA培养基和离体叶片上的适合度(菌丝生长速率、产孢子囊能力及复合适合度指数),比较抗性菌株与其亲本敏感菌株的竞争力,分析对氟吡菌胺表现不同敏感性的菌株对不同药剂的交互抗性,并通过笔者实验室建立的抗性风险量化标准评定马铃薯晚疫病菌对氟吡菌胺的抗性风险。【结果】共获得21个抗性菌株,抗性水平介于61—3 157倍,紫外线诱导孢子囊的突变率为2.78×10~(-7);大多数抗性突变体的适合度与其亲本菌株无显著性差异;竞争力测定试验中,2株突变体的第1、3、7代的共18次抗药频率测定中,有3次测定的抗药频率显著低于初始频率,有4次测定的抗药频率显著高于初始频率,其余11次测定的抗药频率与初始频率均无显著性差异;所有突变菌株的抗药性均能稳定遗传;抗氟吡菌胺菌株及其亲本菌株对氟吡菌胺的lgEC_(50)与这些菌株对嘧菌酯、吡唑醚菌酯、霜脲氰、烯酰吗啉、双炔酰菌胺、甲霜灵、氟醚菌酰胺的lgEC_(50)之间的相关系数(r)分别为0.104(P=0.654)、0.311(P=0.170)、0.228(P=0.081)、0.376(P=0.093)、0.214(P=0.351)、0.122(P=0.599)、0.963(P=0.000);致病疫霉对氟吡菌胺基本抗性风险值为15。【结论】氟吡菌胺与氟醚菌酰胺之间存在交互抗性,与嘧菌酯、吡唑醚菌酯、霜脲氰、烯酰吗啉、双炔酰菌胺、甲霜灵之间无交互抗性,马铃薯晚疫病菌对氟吡菌胺的固有抗性风险为高度,应加强马铃薯晚疫病菌对氟吡菌胺的抗性风险管理,建议生产上将氟吡菌胺与其他类药剂交替或混合使用。  相似文献   

8.
In order to assess the effects of chemical properties of soil salinity on electrical conductivity of 1：5 soil/water extract （EC1：5）, the study focused on revealing the main chemical factors contributing to EC of soil extracts and their relative importance. The relationship between EC1：5 and the chemical properties of soil salinity in the delta oasis of Weigan and Kuqa rivers, China, were studied using path coefficient analysis, a path analysis method. We studied each key element affecting EC1：5 either directly or indirectly. The results obtained show that the salt content, total dissolved solids （TDS）, and the sum of the sodium ion concentration and the kalium ion concentration are the most influential factors on 1：5 soil/ water extract （EC1：5） in the 0-10 cm and the 30-50 cm soil layer. The results show that the sequence of direct path coefficients in the 0-10 cm and the 30-50 cm soil layers on soil conductivity is TDS→Na^＋ ＋ K^＋→Salt content→Ca^2＋→Cl-→the sodium dianion ratio （SDR）→pH→ SO4^2-→HCO3^-→Mg^2＋→the soluble sodium percentage （SSP） sodium absorption ratio （SAR） and TDS→Salt content→Na^＋ ＋ K^＋→Ca^2＋→SDR→Mg^2＋→HCO3^-→SSP→pH→SO4^2-→SAR→Cl^-. The salt content, chlorine ion, and SAR are the main factors affecting 1：5 soil/water extract （EC1：5） in the 10-30 centimeter soil layer. The order of direct path coefficients result is as follows： Salt content→Cl^-→SAR→SSP→TDS→Ca^2＋→Mg^2＋= SO4^2-→HCO3^-→pH→SDR→Na^- ＋ K^＋. Moreover, the effects of HCO3^-, pH were very weak. Though the direct path coefficients between EC1：5 and SAR, SO4^2- and Ca^2＋ were not high, influence of other chemical factors caused the coefficients to increase, making the summation of their direct and indirect path coefficients relatively high. The models of the different soil layers were structured separately. Evidences showed that multiple regression relations between EC1：5 and most of the primary factors had sound reliability and very good accuracy. The research results can serve as a reference to the scientific management amelioration and utilization of saline in the Delta Oasis of Weigan and Kuqa rivers.  相似文献   

9.
【目的】番茄叶霉病是危害温室番茄的重要病害之一,其致病菌对常用杀菌剂已产生不同程度的抗性,亟待开发高效替代药剂。研究旨在探索番茄叶霉病菌（Fulvia fulva）对咯菌腈的敏感性,建立敏感性基线,明确咯菌腈在田间的防治效果。【方法】在山东济南、泰安、聊城、潍坊、莱芜、淄博6个蔬菜产区采集感叶霉病的番茄叶片,经分离纯化后,培养得到126株番茄叶霉菌株;采用菌丝生长速率法和孢子萌发法,测定咯菌腈对3株代表菌株菌丝生长、分生孢子萌发和芽管伸长3个生长发育阶段的抑制活性;利用菌丝生长速率法测定不同地区的126株菌株对咯菌腈的敏感性,并建立敏感性基线。通过两年的田间试验,评价咯菌腈的保护作用和治疗作用。【结果】咯菌腈对番茄叶霉病菌芽管伸长和菌丝生长均有较强的抑制活性,平均EC50值分别为0.30和0.80 μg·mL-1,而对孢子萌发抑制作用较弱,平均EC50值均＞100 μg·mL-1。不同地区番茄叶霉病菌群体间对咯菌腈的敏感性均无显著差异。其中,潍坊地区叶霉菌株对咯菌腈敏感性最高,平均EC50值为0.43 μg·mL-1;淄博地区叶霉菌株敏感性相对较低,平均EC50值为0.79 μg·mL-1。泰安、济南、聊城、莱芜地区的叶霉菌株敏感性无显著差异,平均EC50值分别为0.65、0.75、0.71、0.58 μg·mL-1。咯菌腈对供试菌株菌丝生长的EC50值在0.16-1.69 μg·mL-1,平均值为0.64 μg·mL-1,敏感性频率呈单峰曲线分布,符合正态分布,可作为番茄叶霉病菌对咯菌腈的敏感性基线。2016-2017年田间试验表明,咯菌腈对番茄叶霉病均具有较好的防治效果,咯菌腈在60.75 g a.i./hm2剂量下对番茄叶霉病保护作用和治疗作用防治效果分别为72.21%-75.02%和61.94%-70.65%,均显著高于对照药剂苯醚甲环唑100 g a.i./hm2、代森锰锌700 g a.i./hm2和甲基硫菌灵540 g a.i./hm2,与氟吡菌酰胺150 g a.i./hm2防治效果差异不显著;咯菌腈有效成分为40.50 g a.i./hm2时对番茄叶霉病保护作用和治疗作用的防治效果分别高于对照药剂甲基硫菌灵540 g a.i./hm2的保护和治疗防治效果。2017年咯菌腈有效成分为20.25 g a.i./hm2时对番茄叶霉病保护作用和治疗作用的防治效果分别显著高于对照药剂代森锰锌700 g a.i./hm2和甲基硫菌灵540 g a.i./hm2的保护作用和治疗作用的防治效果。咯菌腈对番茄叶霉病的保护作用均高于治疗作用。【结论】咯菌腈对番茄叶霉病菌菌丝生长和芽管伸长具有显著的抑制作用,而对孢子萌发基本无抑制作用,山东省6个蔬菜产区番茄叶霉病菌对咯菌腈相对比较敏感。该药剂在番茄叶霉病的田间防治中具有一定的应用潜力。  相似文献   

10.
【目的】研究广西烟草黑胫病菌对甲霜灵的敏感性,为烟草黑胫病药剂防治提供科学依据。【方法】采用菌落生长速率法对从广西主要烟区采集分离到的196株烟草黑胫病菌株进行对甲霜灵的敏感性测定。【结果】甲霜灵对196株菌株的EC50在0.0691~1.0243 μg/mL,平均EC50为0.3618±0.0297 μg/mL;来自田林县的菌株TL05为最敏感菌株,EC50为0.0691 μg/mL;来自靖西县画洞镇的菌株ZXHD12为最耐药菌株,EC50为1.0243 μg/mL;各烟区烟草黑胫病菌对甲霜灵的敏感性有一定差异,其中南丹、田林县的菌株较敏感,而隆林、靖西、德保、富川县的部分菌株较耐药;196株菌株中,敏感型、一般耐药型和耐药型菌株分别占1.53%、66.84% 和31.63%。【结论】广西烟草黑胫病菌已对甲霜灵产生不同程度的抗性,甲霜灵作为生产上防治烟草黑胫病的主要药剂具有较大的风险,建议生产上甲霜灵与其他杀菌剂进行轮换使用。  相似文献   

11.
This study was designed to control plant fertility by cell lethal gene Barnase expressing at specific developmental stage and in specific tissue of male organ under the control of Cre/lox system, for heterosis breeding of chili pepper （Capsicum annuum L.）. Chili pepper inbred lines （A, D, E, and I） were transformed with Cre gene and Barnase gene situated between loxp, separately, by means of Agrobacterium co-culture. In this study, we had established a high transformation system by extensive study of affecting factors including genotype, selection of marker, and lethal dose. Cotyledon with petiole from 9-11-day-old seeding was pre-cultured on media MR[MB（MS mineral＋vitamine B5）＋BA（6-Benzyladenine） 5.0 mg·L^-1 ＋IAA（indoleacetic acid） 1.0 mg·L^-1＋GA3（gibberellic acid） 1.0mg·L^-1＋sucrose 3%＋agar 6.5g·L^-1] for 2d. The explants were infected by Agrobacterium tumefaciens when their OD600（optical density at 600 nm）reached 0.6-0.9. After co-cultured for 4-5 d on media MC [MB＋BA5.0 mg·L^-1＋IAA 1.0 mg·L^-1 ＋GA3 1.0 mg·L^-1＋sucrose 3% ＋agar 6.5 g·L^-1＋AS （acetosyringone） 200μmol·L^-1, these cotyledons with petiole were cultured on selective differentiation medium in the media MT[MB medium supplemented with BA [5.0 mg·L^-1＋ IAA 1.0 mg·L^-1＋ GA3 1.0 mg·L^-1＋ AgNO3 5.0 mg·L^-1＋ CW （coconut water） 5% ＋ Km （kanamycin） 65 mg·L^-1＋ Cb （carbenicillin） 500 mg·L^-1＋ 3% sucrose ＋ agar 6.5 g·L^-1].The Kmr （kanamycin resistant） bud rosettes were elongated on selective elongation medium and rooted on rooting medium. PCR and Southern blotting analysis of Kmr plantlet indicated that the foreign genes had been integrated into the genome of pepper. The transgenic plants with Cre gene developed well, blossomed out, and set fruit normally. The transgenic plants with Barnase gene grew well with normal appearance of flower, but they showed different fertility from complete sterility, partial sterility to complete fertility, and similar results were obtained from in vitro pollen germination experiments.  相似文献   

12.
In this study, the oxidative damage of α-terthienyl （α-T） to the Spodoptera litura （SL） cell and its mechanism were investigated. MTT was used to compare the toxicity of α-T and rotenone to the SL cell. The output of malondialdehyde and relative content of glutathione were determined with 2-thiobarbituric acid （TBA） and 5, 5＇-dithio-bis （2-nitrobenzoic acid） （DTNB）, respectively. Transmission electron microscope （TEM） was employed to observe the influence of α-T on the membrane and organelle of the SL cell. The result showed that the IC50 value of α-T to the SL cell was 0.21 μg mL^-1, whereas the corresponding dose of rotenone was 12.25 μg mL^-1. The output of MDA had the same changing tendency with the concentration of α-T, whereas the content of GSH had the negative correlation with it. According to TEM, the cell membrane and karyotheca swelled and couldn＇t retain integrity, the intracellular substances leaked out, unidentified granules appeared in the SL cell. The mitochondria expanded, and the membrane and subcellular organelle were damaged severely. In this study, it was found that after oxidative damage induced by α-T, the output of MDA increased notably, whereas the relative content of GSH decreased. This indicated that the antioxidant ability of cell weakened. The result of TEM implied that the SL cell suffered from oxidative damage under the appointed dose.  相似文献   

13.
The paper was to find the bacteria to degrade aflatoxin B 1 （AFB 1） and realize the application of biological degradation on AFB 1. Using cumarin as the carbon source and energy on the first screening, then the ten strains which were first screened out were taken to degrade AFB 1 100 pg kg^-1. Strain NMO-3 was screened out of ten strains, the degradation ratio of AFB 1 reached 85.7%, which was more prominent than the others （P 〈 0.01）. With the analysis of colony morphology, physiological and biochemistry experiments, and 16S rDNA gene sequence, the strain NMO-3 was finally identified as Stenotrophomonas sp. Using cumarin as the carbon source and energy could screen out the AFB 1 degradation strains. Acute toxicity tests show that the viable number of NMO-3 lower than 3.12 × 10^10 cfu mL-1 is safety. The crude enzyme was obtained by 65% ammonium sulfate fractionation, and it could degrade AFB1. It is the first report for the strain＇s detoxi- AFB1.  相似文献   

14.
1997-2001年在内蒙古自治区和甘肃省马铃薯主产区采集马铃薯晚疫病菌并进行了交配型和药剂敏感性测定。结果为：采自内蒙古的143株菌中有140株是典型A1交配型、3株是可自育的A1交配型；采自甘肃的41株菌中有40株是典型A1交配型、1株为可自育的A1交配型；二省都未发现A2交配型。表明内蒙古和甘肃马铃薯主产区的晚疫病菌以A1交配型占绝对优势。对甲霜灵（metalaxyl)的敏感性测定显示：内蒙古菌株中有50．8％表现高度抗性、42．5％表现中度抗性、只有6．7％表现敏感，说明内蒙古马铃薯主产区的晚疫病菌普遍对甲霜灵具有了抗性；甘肃的菌株中，26．8％表现高度抗性、29．3％表现中度抗性、43．9％表现敏感；同时发现甲霜灵可刺激某些技性菌株的生长。试验还测定了35株菌对烯酰吗啉(dimethomarph)和腈嘧菌脂(mzoxystrobin)的敏感性：其中对烯酞吗啉表现敏感的占94％、中度敏感的占6％；对腈嘧菌脂敏感的占71．4％，中度敏感的占28.6％；未发现对二种药剂高抗或不敏感菌株，且烯酰吗啉和腈嘧菌脂与甲霜灵均无交互抗性。  相似文献   

15.
【目的】研究广西烟草黑胫病菌对甲霜灵的敏感性,为烟草黑胫病药剂防治提供科学依据。【方法】采用菌落生长速率法对从广西主要烟区采集分离到的196株烟草黑胫病菌株进行对甲霜灵的敏感性测定。【结果】甲霜灵对196株菌株的EC50在0.0691-1.0243μg/mL,平均EC50为0.3618±0.0297μg/mL;来自田林县的菌株TL05为最敏感菌株,EC50为0.0691μg/mL;来自靖西县画洞镇的菌株ZXHD12为最耐药菌株,EC50为1.0243μg/mL;各烟区烟草黑胫病菌对甲霜灵的敏感性有一定差异,其中南丹、田林县的菌株较敏感,而隆林、靖西、德保、富川县的部分菌株较耐药;196株菌株中,敏感型、一般耐药型和耐药型菌株分别占1.53%、66.84%和31.63%。【结论】广西烟草黑胫病菌已对甲霜灵产生不同程度的抗性,甲霜灵作为生产上防治烟草黑胫病的主要药剂具有较大的风险,建议生产上甲霜灵与其他杀菌剂进行轮换使用。  相似文献   

16.
咯菌腈对四种牡丹叶片病原真菌的抑制活性   总被引：2，自引：1，他引：1  
【目的】探究咯菌腈对牡丹黑斑病菌(Alternaria suffruticosae)、黄斑病菌(Phyllosticta commonsii)、腔孢叶斑病菌(Hainesia lythri)和叶霉病菌(Cladosporium paeoniae)菌丝生长、孢子萌发、芽管伸长及产孢的抑制活性,分析咯菌腈在牡丹病害化学防治上的应用前景。【方法】采用菌丝生长速率法测定咯菌腈对菌丝生长的抑制活性,采用涂布平板法测定咯菌腈对孢子萌发、产孢时间及产孢量、芽管伸长及芽管和孢子形态的影响。【结果】咯菌腈对腔孢叶斑病菌菌丝生长的抑制作用最强,EC_(50)为0.01μg·mL~(-1),其次为黑斑病菌和黄斑病菌,分别为0.07和0.35μg·mL~(-1);咯菌腈对4种病菌的孢子萌发均有较强的抑制作用,对腔孢叶斑病菌的抑制作用最强,其EC_(50)为1.26μg·mL~(-1),对其他3种病菌孢子萌发的EC_(50)在3.27—3.45μg·mL~(-1);0.1μg·mL~(-1)咯菌腈对4种病菌分生孢子芽管伸长的抑制率在40%—70%,表明咯菌腈对4种病菌分生孢子芽管伸长均有明显的抑制作用,浓度越大抑制作用越强,各浓度间差异显著,其中对腔孢叶斑病菌芽管伸长抑制的EC_(50)为0.04μg·mL~(-1),抑制作用最强,对其他3种病菌芽管伸长的EC_(50)在0.08—0.22μg·mL~(-1);咯菌腈对黑斑病菌和黄斑病菌分生孢子和芽管的致畸作用强烈,可导致孢子及芽管膨大、过度分枝,而对叶霉病菌和腔孢叶斑病菌致畸作用较弱,芽管及孢子形态基本正常;咯菌腈可推迟黑斑病菌、黄斑病菌及叶霉病菌的产孢时间,对黑斑病菌产孢量的抑制作用最强,EC_(50)为0.05μg·mL~(-1),对叶霉病菌次之,EC_(50)为0.38μg·mL~(-1),但对腔孢叶斑病菌产孢有促进作用。【结论】咯菌腈对牡丹黑斑病菌及腔孢叶斑病菌的菌丝生长、孢子萌发及芽管伸长均有很强的抑制作用,但对腔孢叶斑产孢具有一定的促进作用;对叶霉病菌和黄斑病菌孢子萌发及芽管伸长、黄斑病菌菌丝生长及叶霉病菌产孢的抑制作用强烈;由于咯菌腈内吸活性较弱,无法抑制已侵入牡丹叶片的病原真菌的生长,故建议作为保护剂在病害发生前施用。  相似文献   

17.
旨在明确云南省马铃薯春作区晚疫病菌对甲霜灵的敏感性,为马铃薯晚疫病化学防治提供参考。采用菌落直径法对2018-2020年采自云南省春作区的301株马铃薯晚疫病菌进行甲霜灵敏感性测定,结果显示:甲霜灵高抗、中抗、敏感菌株分别占测定菌株的76.41%、21.26%和2.33%。研究结果表明,2018-2020年云南省马铃薯春作区晚疫病菌甲霜灵抗性菌株已高达97.67%,甲霜灵已不能在云南省春作区用于防治晚疫病。  相似文献   

18.
辣椒疫病防治剂的室内筛选*   总被引：1，自引：0，他引：1  
 用菌丝生长抑制法和孢子囊萌发抑制法分别测定了烯酰吗啉、氢氧化铜、王铜、甲霜灵、福美双、三乙膦酸铝、氨基寡糖素、霜霉威、百菌清、代森锰锌等10种杀菌剂对辣椒疫霉菌的毒力。结果表明,烯酰吗啉对辣椒疫霉菌菌丝生长的抑制效果最好,EC50为1.06 μg/mL;氢氧化铜对孢子囊萌发的抑制效果最好,EC50为1.68 μg/mL;代森锰锌对菌丝生长和孢子囊萌发也具有较好的抑制作用;霜霉威对辣椒疫霉菌的菌丝生长和孢子囊萌发几乎都没有抑制作用。对辣椒疫霉菌产孢子囊培养基的筛选结果为米糠琼脂培养基为最佳培养基,产孢子囊量最多且个体较大、均匀一致。  相似文献   

19.
The propagation of laser light in kiwifruit (Actinidia deliciosa) tissue was measured by backscattering imaging and modelled with the Monte Carlo (MC) method. The parameters of the vision system (8 bit/channel camera, 27.42 μm/pixel resolution) and the laser module (785 nm, 45 mW, Ø1 mm) were utilized in simulation. The required number of the photons was optimized with time-resolved MC model. The injected photon pulse travelled further than the beam radius and the calculated intensity fell below the noise level of the camera within 1 ns time. This short pulse contains 2.49 × 108 photons and its application reduced computation load compared to the amount emitted within the integration time of 0.5–8.3 ms. The statistical effects of the optical properties of the tissue, scattering coefficient (μs) absorption coefficient (μa) and anisotropy factor (g), on photon flux was evaluated within ±20% range relative to expected mean values of μa = 0.9 cm−1 and μs = 40 cm−1. The anisotropy factor was taken into account using the Heyney–Greenstein phase function and was adjusted to g = 0.8 ± 20%. Because individual significance of each optical property was also analysed, scattering (μs) and transport corrected reduced scattering coefficients (μ′s=[1−g]μs) must be distinguished. The multi-factor ANOVA test pointed out the highest importance (p < 0.001) of the anisotropy factor amongst scattering and absorption coefficients.In the kiwi backscattering images, rotation of the intensity profiles was observed as a result of changing anisotropy. The measured and calculated profiles were compared to estimate the anisotropy factor of kiwifruits. Significant difference (p < 0.01) was found between anisotropy of premium quality and overripe pieces with respect to the fruit texture properties.  相似文献   

20.
为了明确霜脲氰、烯酰吗啉、精甲霜灵、氟啶胺和双炔酰菌胺对番茄晚疫病菌的抑菌作用及其田间防效,采用菌丝生长速率法测定了5种杀菌剂对番茄晚疫病菌的室内毒力,并进行了田间防效试验。结果表明:5种杀菌剂均对番茄晚疫病菌表现出很强的抑菌活性;72%霜脲氰·锰锌可湿性粉剂1 500 g/hm2、50%烯酰吗啉可湿性粉剂300 g/hm2、68%精甲霜灵·代森锰锌水分散粒剂1 224 g/hm2、500 g/L氟啶胺悬浮剂200 g/hm2和23.4%双炔酰菌胺悬浮剂150 g/hm2对番茄晚疫病的田间防治效果均80%。霜脲氰、烯酰吗啉、精甲霜灵、氟啶胺和双炔酰菌胺仍可用于番茄晚疫病的防治。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号