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1.
Gyung Ja Choi Seon-Woo Lee Kyoung Soo Jang Jin-Seog Kim Kwang Yun Cho Jin-Cheol Kim 《Crop Protection》2004,23(12):1215-1221
Three substances that show antifungal activity against Blumeria graminis f. sp. hordei were isolated from roots of Rumex crispus and identified as chrysophanol, parietin, and nepodin. The substances were tested for plant disease control activity in vivo against six plant pathogenic fungi. All specifically reduced the development of barley powdery mildew. The concentrations required for 50% disease control were 4.7 μg/ml for chrysophanol, 0.48 μg/ml for parietin, and 20 μg/ml for nepodin. These agents showed both curative and protective activity against barley powdery mildew. Chrysophanol (100 μg/ml) and nepodin (400 μg/ml) were more effective than the fungicides fenarimol (30 μg/ml) and polyoxin B (100 μg/ml), under glasshouse conditions, against cucumber powdery mildew, which is caused by Podosphaera xanthii. Parietin (30 and 10 μg/ml) reduced the development of cucumber powdery mildew as efficiently as fenarimol (30 μg/ml) and more effectively than polyoxin B (100 μg/ml). 相似文献
2.
西沙群岛草海桐链格孢叶斑病发生普遍,前期笔者鉴定了该病的病原菌为长柄链格孢菌（Alternaria longipes）。为进一步明确该病原菌的生物学特性及其对杀菌剂的敏感性,采用生长速率法对长柄链格孢菌的生物学特性进行了初步研究,并测定了苯醚甲环唑等13种杀菌剂对该病原菌的室内毒力。结果表明：该菌菌落最适生长培养基为马铃薯葡萄糖固体培养基（PDA）,其次是马铃薯蔗糖固体培养基（PSA）;适宜生长温度范围为25~30℃,最适生长温度为28℃;适宜生长pH为5.0~7.0,最适pH为6.0;最佳碳源为蔗糖,而果糖不利于菌落生长;最佳氮源为甘氨酸,而尿素不利于菌落生长;光照时间对菌落生长无显著影响。室内毒力测定表明,苯醚甲环唑水分散粒剂的抑菌效果最好,EC50值为0.15 μg/mL,其次是氟硅唑乳油、己唑醇悬浮剂和戊菌唑乳油,其EC50值分别为0.37、0.44和0.51 μg/mL,嘧菌酯悬浮剂和多菌灵可湿性粉剂的抑菌效果最差,EC50值均大于3000 μg/mL。 相似文献
3.
为探讨LED光源在金线莲工厂化栽培中的应用,利用研发的具有不同比例红（R）、蓝光（B）的LED灯作为光源,以白色荧光灯为对照（CK）,设置以下5个试验处理,T1：R/B(3/7), PPFD 20 μmol/(m2·s);T2：R/B(7/3), PPFD 20 μmol/(m2·s);T3：R/B(3/7), PPFD 30 μmol/(m2·s);T4：R/B(7/3), PPFD 30 μmol/(m2·s);T5：R/B(7/3), PPFD 50 μmol/(m2·s),研究不同比例红蓝光源及其光照强度对金线莲的生长、光合作用、叶绿素荧光反应和生理特性的影响。结果表明：与对照处理相比,T4、T5处理的金线莲株高、茎粗、植株干鲜重显著提高;T5处理的金线莲叶片净光合速率显著高于其他处理,而T1、T3处理间差异不显著,但显著高于T2、T4处理。不同比例红蓝光处理下金线莲叶片的叶绿素含量显著高于对照处理,在相同的光照强度下,R/B(7/3)处理的金线莲叶片叶绿素含量大于R/B(3/7)处理。不同比例红蓝光源处理的金线莲叶片最大光化学效率、光系统II活性均显著高于对照处理;红光比例减少,蓝光比例增加,可降低金线莲叶片最大光化学效率、光系统II活性,同时光系统II实际光化学效率和光合电子传递效率也随之降低。T2处理可有效提高金线莲叶片SOD和CAT活性,但POD活性降低;T4处理下金线莲叶片POD和CAT活性降低,SOD活性升高;与对照相比,T1处理的金线莲叶片MDA含量显著增加,较对照提高19.4%,而T5处理与对照差异不显著。综合各处理金线莲生长来看,T5处理R/B(7/3), PPFD 50 μmol/(m2·s)的金线莲生长最好,保持较高的光合速率及生理活性。 相似文献
4.
为明确百香果炭疽病菌（Colletotrichum karstii）的生物学特性,并筛选出防治效果较好的杀菌剂,采用生长速率法探究该病菌的生物学特性及9种杀菌剂对该病菌的室内毒力。结果表明：该病菌适宜在萨氏（SDAY）培养基上生长,适宜pH为6~9,适宜生长温度为20~30 ℃,最适温度为25 ℃,可高效利用蔗糖与甘氨酸;室内毒力测定发现9种杀菌剂对该病菌菌丝生长均有一定的抑制作用,其中75%肟菌·戊唑醇WG的抑制效果最好,EC50为0.0667 mg/L,其次为18.7%丙环·嘧菌酯SE、42.4%唑醚·氟酰胺SC、25%吡唑醚菌酯SC、50%咪鲜胺锰盐WP,EC50值分别为0.3335、0.4567、0.4630、0.8187 mg/L。 相似文献
5.
2007—2018年,本课题组在对中国木薯主栽区的病害调查中发现了一种国内尚未记载的叶斑病。病害主要危害叶片,形成圆形或不规则形、常密集分布的白色至黄褐色的病斑,故命名为白点病。该病在云南、海南、广西等地区均有发生,绝大多数主栽品种和部分新育成种质均受害。经病菌分离和回接实验以及病菌形态观察、核糖体基因间隔区和β-微管蛋白基因序列分析,将该病病原鉴定为链格孢(Alternaria alternata)。病菌离体培养实验表明,菌丝生长最适条件为V9、OA、CA或CMA培养基,28℃,D-麦芽糖、D-山梨醇或D-乳糖,硝酸钠,光暗交替,pH8。分生孢子萌发最适温度为28℃,而致死温度为60℃处理5min。杀菌剂敏感性测定结果表明,在所测试的10种药剂中,10%苯醚甲环唑WG和25%吡唑醚菌酯WG的EC50值分别为0.12、0.47 mg/L,对菌丝生长抑制率最高。 相似文献
6.
Leen C. Davidse Oda C. M. Gerritsma Joy Ideler Klaas Pie Grardy C. M. Velthuis 《Crop Protection》1988,7(6):347-355
The activity of the phenylamide fungicides metalaxyl, cyprofuram, benalaxyl and oxadixyl against phenylamide-sensitive and phenylamide-resistant strains of Phytophthora megasperma f. sp. medicaginis and Phytophthora infestans has been compared in several tests. Metalaxyl showed the highest activity amongst the four fungicides against mycelial growth of sensitive strains on agar media. Benalaxyl and cyprofuram showed the highest activity against resistant strains. RNA synthesis of sensitive strains, measured as [3H]uridine incorporation, was inhibited by about 80% (P. megasperma) and by about 40% (P. infestans) by all phenylamides at concentrations of 1 μg/ml. At higher concentrations inhibition remained at this level, indicating that only part of the RNA synthesis was inhibited. RNA synthesis of resistant strains was completely insensitive to metalaxyl and oxadixyl at concentrations as high as 200 μg/ml. Cyprofuram, however, at concentrations above 1 μg/ml (P. megasperma) and 10 μg/ml (P. infestans) was inhibitory and at 200 μg/ml this compound almost completely inhibited the phenylamide-sensitive part of the RNA synthesis of both strains. In contrast to the other phenylamides, benalaxyl affected [3H]uridine uptake into mycelium at concentrations higher than 10 μg/ml, and at 100 μg/ml inhibition of uptake was almost total with both sensitive and resistant strains of both Phytophthora species. Inhibition of [3H]uridine uptake obviously is a feature of a second mechanism of action of benalaxyl. Endogenous RNA polymerase activity of isolated nuclei from sensitive strains of P. megasperma was inhibited at phenylamide concentrations as low as 0·1 μg/ml whereas that from resistant strains was not affected at concentrations as high as 100 μg/ml. Similarly, endogenous nuclear RNA polymerase activity of sensitive P. infestans strains appeared to be more sensitive to the phenylamides than that of resistant P. infestans strains. This suggests that resistance that developed in field strains of P. infestans has a basis similar to that of mutagen-induced resistance in laboratory strains of P. megasperma. Tests of the fungicidal activity of the phenylamides determined in a lucerne seedling assay (P. megasperma) and a detached potato leaf assay (P. infestans) clearly differentiated between sensitive and resistant strains. Resistance levels to cyprofuram and benalaxyl were as high as those to metalaxyl and oxadixyl, indicating that the additional effect of a second mechanism of action of benalaxyl and the property of cyprofuram to inhibit RNA synthesis of resistant strains at higher concentrations are of limited practical importance for counteracting phenylamide resistance. 相似文献
7.
通过探讨白木香冠层光谱和形状特征与叶片含锌量的模型关系,实现幼龄白木香冠层含锌量的快速无损诊断,为实现白木香智能化培育经营提供新思路。以幼龄白木香为研究对象,通过多光谱相机获取白木香冠层图像,结合相位相关法及贝叶斯分割法精确提取白木香冠层,在应用偏最小二乘（partial least squares, PLS）算法对图像光谱和形状特征进行降维的基础上,分别构建偏最小二乘回归（partial least squares regression, PLSR）模型和偏最小二乘-广义可加模型（partial least squares- generalized additive models, PLS-GAM）以图像特征对含锌量进行估测和分析,并通过比较模型评价指标与常用套索回归（lasso regression, LassoR）和多元逐步回归（multiple stepwise regression, MSR）模型进行对比,确定适用于白木香锌含量估测的最佳模型。研究表明：（1）结合相位相关法和贝叶斯算法能够较好地分割出白木香冠层图像,效果显著优于对各波段图像进行直接分割的方法;（2）基于多光谱图像特征提取6个主成分CF1、CF2、CF3、CF4、CF5和CF6,PLSR建模分析结果表明CF1和CF2与白木香冠层含锌量具有显著的线性关系,模型调整后R2adj为0.475;（3）PLS-GAM建模分析结果表明,CF1、CF2和CF4与白木香冠层含锌量均存在显著的非线性关系,模型调整后R2adj为0.679,显著高于基于线性关系构建的PLSR模型;（3）经过模型评价对比,PLS-GAM模型估测精度最高,RMSE为0.095,较PLSR、LassoR、MSR模型分别降低了26.4%、43.1%和34.9%,为适用于估测白木香冠层含锌量的最优模型。因此,结合相位相关法及贝叶斯分割法能够实现对白木香冠层多光谱图像的精准分割,基于光谱和形状特征构建的PLS-GAM模型对白木香冠层含锌量具有良好的估测效果,有利于推动白木香微量元素诊断的研究进程,对幼龄白木香的智能化作业有重要意义。 相似文献
8.
为探究枯草芽孢杆菌与化学杀菌剂协同防治橡胶树根病的可行性,为橡胶树根病的可持续防治提供依据。采用抑菌圈法和平板菌落计数法分别测定7种杀菌剂和枯草芽孢杆菌Czk1菌株对橡胶树红根病菌、褐根病菌的毒力以及杀菌剂与Czk1菌的生物相容性,并用Horsfall法确定复配方案。结果表明："根康"对橡胶树红根病菌和褐根病菌的EC50分别为0.6253、0.0522 μg/mL,EC50均最低且与Czk1菌有很好的生物相容性。"根康"（EC50=0.6253 μg/mL）与Czk1(EC50=6.46×10 7 CFU/mL)混配,体积比V(Czk1)∶V("根康")=7∶3时,对红根病菌的增效比率值IR值为1.60;"根康"（EC50=0.0522 μg/mL）与生防菌Czk1（EC50=2.33×10 8 CFU/mL）混配,体积比V(Czk1)∶V("根康")=7∶3时,对褐根病菌IR值为1.51。研究表明,"根康"可与Czk1联用协同防治橡胶树根病,菌药复配剂的防效明显优于单剂"根康"和单剂生防菌Czk1的防效,且混配剂中"根康"使用量只有单剂的1/3,大幅降低了化学药剂的使用量。 相似文献
9.
Occurrence of resistant strains of Botrytis cinerea to anilinopyrimidine fungicides in table grapes in Chile 总被引：1，自引：0，他引：1
Effort to control gray mold caused by Botrytis cinerea failed in a table grapevine (Vitis vinifera) vineyard near Santiago, Chile where cyprodinil (Vangard 50 WP), a new fungicide of the anilinopyrimidine group, had been applied alone up to four times per year during two growing seasons. A relatively high frequency (38.5%) of resistant isolates of B. cinerea (EC50 for mycelial growth inhibition varied from 2.9 to 4.84 μg ml−1) may explain the partial loss of field control efficacy obtained. Resistance was correlated with a complete loss of in vivo sensitivity to cyprodinil. Resistant isolates of B. cinerea showed cross resistance to the anilinopyrimidines fungicides mepanipyrim and pyrimethanil. Cyprodinil partially impaired conidia germination and differentially affected conidial germination of resistant and sensitive isolates. Significant differences (p<0.05) in growth rate, sclerotia production and osmotic sensitivity were found among isolates of B. cinerea, but no correlation could be drawn between these biological differences and resistance or sensitivity. This indicates a disruptive selection characteristic of monogenic resistance. Thus, strategies were implemented to avoid the further development and spread of resistance in B. cinerea to the anilinopyrimidine fungicides. To our knowledge this constitutes the first mention of resistance in B. cinerea populations to anilinopyrimidine fungicides in South America. 相似文献
10.
为有效利用热区农业废弃物砂仁茎叶及优质牧草资源,添加不同比例的砂仁茎叶与‘热研4号’王草混合青贮,研究其对王草营养成分和发酵品质的影响,筛选最佳混合青贮比例,以期提高饲料营养品质。按照完全随机设计试验,鲜重基础条件下,‘热研4号’王草和砂仁茎叶的混合比例依梯度分为100∶0（对照组）、90∶10（A1组）、80∶20（A2组）、70∶30（A3组）,每组均加入10 mg/kg的EM菌,青贮30 d后开封进行检测分析。结果表明：各试验组乳酸（LA）/乙酸（AA）比值均大于2,均有少量丙酸（PA）和丁酸（BA）检出。A2和A3组感官品质为优良;随着砂仁茎叶比例升高,青贮料pH显著升高,各处理组的干物质（DM）、粗蛋白（CP）、粗脂肪（EE）和粗灰分（ASH）均呈现上升趋势;铵态氮/总氮（NH3-N/TN）、LA和AA含量逐渐降低,且A3组NH3-N/TN显著低于CK和A1组（P<0.05）;各处理组LA和AA含量显著低于对照组（P<0.05）,但各处理组间LA和AA含量差异不显著（P>0.05）;A3组的DM、CP、EE和ASH含量显著高于CK（P<0.05）,水溶性碳水化合物（WSC）含量显著低于CK（P<0.05）,且A1、A2和A3组间差异不显著（P>0.05）,中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）含量显著低于CK（P<0.05）;从营养价值和发酵品质考虑,建议砂仁茎叶与‘热研4号’王草以30∶70比例混合青贮较为适宜。 相似文献
11.
为了明确苦瓜双色平脐蠕孢叶斑病菌（Bipolaris bicolor）的生物学特性及其对杀菌剂的敏感性,研究了不同培养条件对该病原菌菌丝生长的影响,并测定了10种杀菌剂对该病原菌的抑制作用。结果表明：该病原菌菌丝生长最适温度为25~30 ℃,最适pH范围为6~7,适宜培养基为马铃薯蔗糖培养基（PSA）和玉米粉培养基（CMA）,持续黑暗和光暗交替有利于菌丝生长;不同碳源和氮源对菌丝生长的影响差异显著,其中葡萄糖和蛋白胨分别为最适碳源和氮源,菌丝生长致死温度为45 ℃。250 g/L苯醚甲环唑乳油毒力最强,EC50为0.0233 mg/L,其次为250 g/L吡唑醚菌酯悬浮剂、20%抑霉唑水乳剂和50%嘧菌环胺水分散粒剂。 相似文献
12.
芝麻棒孢叶斑病是芝麻常发性病害,严重影响着芝麻的产量和品质。为确定芝麻棒孢叶斑病防治的最佳时期,制定有效的药剂防治措施,2017-2019年对黄淮芝麻主产区平舆县的棒孢叶斑病发生情况进行了监测,并测定了16种杀菌剂的室内毒力和田间防效。结果表明,芝麻棒孢叶斑病的发生初期为现蕾期-初花期,病情发展的转折期为初花期-盛花初期(黄淮产区为7月20日-31日,此时田间发病率小于3%或病情指数小于1)。16种供试杀菌剂中己唑醇、咪鲜胺、氟硅唑、戊唑醇、苯醚甲环唑、腐霉利、噻呋酰胺和咯菌腈对芝麻棒孢叶斑病菌的毒力较强,EC50分别为1.5734×10-4、0.1248、0.7128、1.3922、2.0014、2.7323、5.4327、6.1285 mg/L;噻呋酰胺、己唑醇、嘧菌酯、戊唑醇和苯醚甲环唑的田间防效和增产效果较好,防效分别为67.19%、65.86%、61.17%、60.87%、61.83%,增产率分别为38.96%、36.86%、39.72%、34.96%、38.56%;苯醚甲环唑、己唑醇、嘧菌酯和戊唑醇施药2次的防效和增产效果最佳。综... 相似文献
13.
Deena Errampalli Rick D. Peters Kathy MacIsaac Danny Darrach Peter Boswall 《Crop Protection》2006,25(12):1231-1237
The pre-planting seed tuber treatments of chlorine dioxide (ClO2), thiophanate-methyl (TPM), and a combination treatment of ClO2, followed by TPM, were evaluated for control of stem canker and black scurf (Rhizoctonia solani), and storage rots; black scurf, common scab (Streptomyces scabies), dry rot (Fusarium spp.) and silver scurf (Helminthosporium solani) on potato (Solanum tuberosum L.) cv. Kennebec. Field experiments were conducted in two consecutive years, 1999 and 2000, at the Agriculture and Agri-Food Canada Research Farm in Harrington, Prince Edward Island (PEI), Canada. The combination treatment of ClO2 (200 μg g−1) and TPM (50 g active ingredient100 kg−1 of tubers) significantly (P=0.05) reduced stem canker and black scurf on progeny tubers at harvest and after storage. The low incidence of scab and dry rot in untreated controls hindered the evaluation of the efficacy of the combination treatment and also showed that conditions were not favourable for disease development during this period at Harrington. The combination treatment was not effective on silver scurf in storage. A comparison among control, ClO2, TPM, and the combination treatment indicates that pre-planting ClO2 treatment may have killed the majority of the black scurf sclerotia on the tuber surface and that the combination of TPM fungicide treatment following ClO2 treatment gave protection to progeny tuber by suppressing the growth of the R. solani. A higher marketable yield was observed in the combination treatment as compared with the untreated control. Phytotoxicity was not observed in tubers treated with the combination treatment. 相似文献
14.
卷瓣凤梨属（Alcantarea）植物是凤梨科植物中较晚被引入中国的观赏凤梨之一,与目前国内常见的观赏凤梨商业品种不耐强光不同,卷瓣凤梨属植物较喜光,加上其体型硕大,既可观叶也可赏花,较适合应用于室外园林中。但是不同种和品种对光照的需求各有差异,特别是对于夏季室外全光照环境的耐受性尚未明确。为了研究不同卷瓣凤梨属植物对夏季强光和高温环境的适应性,以3种大型卷瓣凤梨的成熟植株为研究对象,运用Li-6400光合测定仪进行夏季全光照环境下光合特性日变化的测定,并进行光合生理指标与环境因子的相关性分析。3种卷瓣凤梨属植物在夏季高温季的日变化曲线都为双峰型,且都在8：00达到最高点,中午11：00出现谷底,其中帝王卷瓣凤梨（红叶型）的净光合速率（Pn）日变化曲线较为平缓,谷底高而浅,中午Pn显著高于其他2个种,表现出对夏季强光及伴随着的高温环境具有较强的耐受性,且9：00—13：00的Pn下降是由气孔限制引起的;‘优雅’和格拉齐卷瓣凤梨的Pn双峰曲线谷底较深,其中‘格拉齐’的Pn变化最为剧烈,在早晚光线和气温不太高的环境下具有较高的Pn,强光下光合作用下降明显,中午11：00到达谷底,次峰较高,出现在15：00;‘优雅’和‘格拉齐’在上午9：00—13：00的Pn下降是由非气孔限制引起的。气孔导度（Gs）是影响3种凤梨夏季全光照环境下Pn的主要光合生理指标,具有极显著或显著正相关性,但与其他光合生理指标及环境因子间相关系数较低,可能是各因素间存在交互影响所致。3种卷瓣凤梨中,帝王卷瓣凤梨（红叶型）对室外全光照环境的适应较强,植株生长正常,格拉齐卷瓣凤梨和‘优雅’卷瓣凤梨对强光比较敏感,其中‘格拉齐’叶色变黄,‘优雅’则发生叶丛中央的新叶不正常密集生长的现象,因此后2种更适合中午有一定荫蔽的环境,本研究为卷瓣凤梨属植物在室外园林中露地应用提供理论依据。 相似文献
15.
Tobacco brown spot caused by Alteraria alternata is a devastating disease of tobacco worldwide. In this study, we reported the effects of a strobilurin fungicide azoxystrobin and a sterol inhibitor difenoconazole on mycelial growth, spore germination, and control of brown spot. Both mycelial growth and spore germination bioassay results showed that sensitivity of A. alternata to difenoconazole was significantly lower than that to azoxystrobin. Azoxystrobin and the compound of azoxystrobin plus difenoconazole provided excellent control efficacy on tobacco brown spot in field. Disease control efficacies for three sprays of azoxystrobin at doses of 0.094, 0.19 and 0.28 Kg a.i./ha, of azoxystrobin plus difenoconazole at 0.15, 0.22 and 0.29 Kg a.i./ha, and of difenoconazole at 0.12 Kg a.i./ha were between 86.00% and 89.67%, between 86.14% and 89.23%, and between 55.14 and 58.41%, respectively. No phytotoxic symptoms were observed for the fungicides in field. These fungicides could potentially be used for brown spot control in tobacco. 相似文献
16.
菜用甘薯存在产量低、品质差以及在种植过程中由于不合理施肥造成生态环境恶化等问题,因此,针对以上问题开展本研究。氮肥作为农业肥料投入的主要部分,是影响菜用甘薯产量和品质的重要因素,通过设置不同氮素形态配比处理,根据菜用甘薯茎尖产量和品质相关指标的变化,揭示菜用甘薯产量和品质对氮素形态配比的响应机制,为提升菜用甘薯产量和品质的同时减轻因不合理施肥造成环境污染提供理论依据。本研究为大田试验,供试品种为生产上主栽的2个菜用甘薯品种‘福薯18’（F18）和‘鄂薯10号’（E10）,采用两因素裂区试验设计,设5个氮素形态配比处理为：（1）NH4+-N∶NO3--N∶CONH2-N =1∶1∶1 (N1);（2）NH4+-N∶NO3--N∶CONH2-N = 1∶0∶2 (N2);（3）NH4+-N∶NO3--N∶CONH2-N = 2∶0∶1 (N3);（4）NH4+-N∶NO3--N∶CONH2-N = 1∶2∶0 (N4);（5）NH4+-N∶NO3--N∶CONH2-N = 2∶1∶0 (N5)。研究结果表明,N4和N5处理均可显著提高菜用甘薯的茎尖产量、总酚含量、总黄酮含量、可溶性糖含量、苯丙氨酸解氨酶(PAL)酶活性和IbPAL基因表达量;同一时期不同处理间差异显著,随着生育期的不断推进,各项指标的变化呈先升后降的趋势,其中以N4处理效果更为显著,除可溶性糖含量在N3处理下最低外,其他各项指标均在N2处理下最低,由相关性分析证实,总酚、总黄酮和可溶性含量及PAL酶活性与IbPAL基因表达量呈显著正相关,而可溶性糖含量与基因表达量呈负相关,表明可溶性糖含量的变化与IbPAL基因表达无相关性;由氮素形态配比处理可知,相对于N2和N3处理,N4和N5处理为植株提供了更多的NO3--N,由此推断NO3--N在菜用甘薯生长发育过程中起到更为重要的促进作用,而CONH2-N在本研究中对甘薯产量和品质的促进作用并不突出。而N4处理即NH4+-N∶NO3--N∶CONH2-N = 1∶2∶0的配肥方案是促进菜用甘薯产量和品质提升的最佳配施组合。本研究结果可为合理配肥以获得理想的作物产量和品质提供理论依据,为在其他作物上开展相关研究提供参考。 相似文献
17.
襄阳市主要花生种植区土壤中黄曲霉菌分布及产毒力研究 总被引：1，自引：0，他引：1
为掌握襄阳市主要花生种植区土壤中黄曲霉菌的分布和产毒特征,从襄阳市主要花生种植区采集土壤样品36份,进行黄曲霉菌分离、鉴定和产毒力研究。结果表明,襄阳市不同花生种植区土壤中黄曲霉菌落数平均为5997.6 cfu/g,且分布存在显著差异,菌落数由高到低依次为襄州、枣阳、宜城、谷城;鉴定获得黄曲霉菌株中产毒菌株占63.6%,产毒量范围ND～304.9μg/L,不产毒菌株占36.4%;产毒菌株可分为7种产毒类型组合,其中同时产AFB1、AFB2和AFG1三种类型的黄曲霉菌占比最多,为54.0%。在适宜培养条件下,产毒力分析结果为襄州地区每克土壤中黄曲霉菌产AFT的理论值最高,可达2080.0×103μg/L,且其中分离出的菌株平均产毒量最高,为218.7μg/L。可以看出襄阳市花生代表性产区土壤中黄曲霉菌分布数量显著高于我国南、北方花生主产区的平均水平,但其菌株的平均产毒能力却远低于全国其它地区。本研究初步得出了襄阳市花生主产区黄曲霉菌的分布特征和产毒特征,可为襄阳市花生黄曲霉毒素防控提供理论依据。 相似文献
18.
本文建立了气质联用仪测定稻田环境中苯醚甲环唑和嘧菌酯的残留分析方法,对苯醚甲环唑和嘧菌酯在水稻、土壤和田水中的消解动态和残留规律进行了研究。苯醚甲环唑和嘧菌酯在糙米、稻壳、植株、土壤和田水中的最低检测浓度均为0.20 mg/kg,最小检出量为0.2 ng,在不同样品中的平均加标回收率为80.8%~109.5%,相对标准偏差在1.7%~19.7%之间。田间试验结果表明,苯醚甲环唑和嘧菌酯在水稻植株和田水中的残留消解动态规律均符合一级动力学反应模型,苯醚甲环唑在水稻植株和田水中的残留消解半衰期分别为6.3~11.6 d和1.4~11.6 d;嘧菌酯在水稻植株和田水中的残留消解半衰期分别为3.6~8.7 d和2.9~23.1 d。以推荐剂量600 g/hm2和1.5倍推荐剂量900 g/hm2,最多施药3次,距最后一次施药15 d时,苯醚甲环唑和嘧菌酯在糙米中的最高残留量分别为0.461 mg/kg和0.634 mg/kg,低于我国国家标准《食品中农药最大残留限量》(GB2763-2014)中规定的糙米中苯醚甲环唑最大残留限量0.5 mg/kg和欧盟、美国规定的糙米中嘧菌酯最大残留限量5.0 mg/kg。 相似文献
19.
20.
Teruo Nonomura Yoshinori Matsuda Miki Bingo Maiko Onishi Kazuhiko Matsuda Satoshi Harada Hideyoshi Toyoda 《Crop Protection》2001,20(10):935-939
The chemical control agent 3-(3-indolyl)butanoic acid, previously reported as a control agent for the bacterial wilt pathogen Ralstonia solanacearum, was shown to suppress the growth of green algae during hydroponic culture of tomato. The algicidal activity of the compound was effective at 10 μg/ml, completely preventing generation of green algae under non-shaded greenhouse conditions. The algicidal effect was mainly due to suppression of the growth of motile unicellular algal cells tentatively identified as Chlamydomonas spp., which are commonly occurring in the hydroponic solution and vigorously multiply to form an algal mat on the sponge supports. The compound has potential as a non-phytotoxic algicide for hydroponically cultured crop plants. 相似文献