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11.
防治牡丹根腐病的有效药剂筛选 总被引:4,自引:0,他引:4
采用菌丝生长速率法和孢子萌发法,分别测定了咪鲜胺、醚菌酯、苯醚甲环唑、百菌清、多菌灵、代森锰锌等6种杀菌剂对牡丹根腐病菌的室内毒力。结果表明,6种药剂对病菌菌丝生长的EC50大小顺序为:咪鲜胺<多菌灵<代森锰锌<苯醚甲环唑<百菌清<醚菌酯,其中以咪鲜胺对牡丹根腐病病菌的菌丝生长抑制作用最强, EC50为0.200 mg/L;多菌灵、代森锰锌、苯醚甲环唑、百菌清依次减弱,醚菌酯的抑制菌丝生长的作用最小,EC50为33.98 mg/L。6种药剂对病菌孢子萌发的EC50大小顺序为:百菌清<咪鲜胺<苯醚甲环唑<多菌灵<代森锰锌<醚菌酯;其中以百菌清对牡丹根腐病菌的孢子萌发抑制作用最强,EC50为0.343 mg/L;咪鲜胺、苯醚甲环唑、多菌灵、代森锰锌依次减弱,醚菌酯抑制孢子萌发的作用最小,EC50为38.4 mg/L。 相似文献
12.
以对氯苯甲酸、甲醇、水合肼、对硝基苯甲醛、对甲氧基苯甲醛、苯乙酮为原料,合成了对硝基苯甲醛对氯苯甲酰腙、对甲氧基苯甲醛对氯苯甲酰腙及苯乙酮对氯苯甲酰腙。目标化合物的结构通过核磁共振氢谱、元素分析和红外光谱进行了表征,并试验了目标化合物对菜粉蝶幼虫的杀虫活性。活性筛选试验结果表明,对硝基苯甲醛对氯苯甲酰腙的触杀活性和胃毒活性最强。系列浓度试验表明,处理24h后,对硝基苯甲醛对氯苯甲酰腙对菜粉蝶幼虫的触杀活性和胃毒活性的EC50分别为497.85mg/L、287.01mg/L;处理48h后,二者分别为272.21mg/L、145.75mg/L。 相似文献
13.
对非洲凤仙(Impatiens wallerana Hook.f.)茎基腐病的症状进行了描述,结合病原形态特征、培养特性及rDNA-ITS序列分析结果,确定该病害由Rhizoctonia solani Kühn AG4-HG-Ⅰ融合群引起。病菌的生物学特性研究表明:菌丝较适生长温度为25~30℃;菌丝生长较佳的培养基为OA和PSA,较佳的碳源为D-(+)麦芽糖、α-乳糖和可溶性淀粉,较佳的氮源为硝酸钾和硝酸钠;pH=7时菌丝生长最好;光照条件对菌丝生长无影响;菌丝致死条件为51℃、10 min。采用生长速率法测定了病菌对30种杀菌剂的敏感性,结果表明,病菌对≥300亿个· g-1内生芽孢杆菌WP、1000亿个· g-1枯草芽孢杆菌WP、25%肟菌·50%戊唑醇WG、40%氟硅唑EC敏感性较高,对其EC50<1.0 mg· L-1,可以作为田间防治非洲凤仙茎基腐病的首选杀菌剂。 相似文献
14.
An experiment was conducted, in a dark room with controlled temperature (27.3–28.4 °C), to determine the acute toxicity of chlorine concentration to black tiger shrimp (Penaeus monodon fabicus) of sizes 0.02 g, 2.75 g, 8.47 g and 23.65 g. Toxicity tests on each of these shrimp sizes were run in triplicate in glass jars under static conditions without media renewal. The concentration of active chlorine that killed 50% of the shrimp of each size after 24‐h exposure (LC50‐24 h) was used as an indicator of acute toxicity. Chlorine concentrations applied in the shrimp toxicity test ranged from 2.0 to 14.5 mg L?1 in shrimp pond water. As the test water contained total suspended solids of 22.0–85.0 mg L?1 and total ammonia nitrogen of 0.18–0.40 mg L?1, the resultant concentrations of combined residual chlorine ranged from 0.6 to 3.5 mg L?1, which were the effective doses causing shrimp mortality. The test results showed that 24‐h LC50 for average shrimp size at 0.02, 2.75, 8.47 and 23.65 g occurred in water containing combined residual chlorine at a concentration of 0.91, 1.39, 1.74 and 1.98 mg L?1, for which the original application doses were 6.96, 2.05 11.50 and 13.34 mg L?1 respectively. 相似文献
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18.
Ute?FeilerEmail author Ilona?Kirchesch Peter?Heininger 《Journal of Soils and Sediments》2004,4(4):261-266
Background, Goal and Scope To date, standardised bioassays for the assessment of the ecotoxicological potential in sediments and dredged material use
test organisms like bacteria, algae and crustaceae. This paper presents the development and application of a novel sediment
contact test (whole sediment) withMyriophyllum aquaticum, a representative of rooted aquatic macrophytes. The aim of the present study is to demonstrate the value of a sediment contact
test with rooted macrophytes as a supplement to existing test batteries in order to improve the assessment of sediment toxicity.
Methods The newly developed sediment contact test withMyriophylhim aquaticum was applied to natural whole sediments. For performing the test, whorls ofMyriophyllum aquaticum were directly planted in the native sediment and incubated in the light at 24°C (cf. section results and discussion). The
end points of the test were the number of the shoots and the fresh weight of the whole plants. The duckweed growth inhibition
test withLemna minor according to ISO/DIS 20079 was performed in pore waters from sediment samples. The results of the sediment contact test withMyriophyllum aquaticum were compared with each other and with those of the aquatic duckweed test.
Results and Discussion A test protocol for the new plant-based sediment contact test using the aquatic plantMyriophyllum aquaticum as an indicator was developed. The best control sediment proved to be the OECD sediment (OECD 207). A test period of 10 days
appeared to be sufficient for the test. The increase of biomass and the derived growth rate were found to be the most suitable
evaluation parameters. The growth behaviour ofMyriophyllum aquaticum differed depending on the origin of sediments. Therefore, plant-affecting contamination, that is bound in sediments, was
indicated.
Conclusions The novel sediment contact test withMyriophyllum aquaticum can indicate phytotoxic effects in sediments. Therefore, it allows a better assessment of the overall-toxicity in whole sediments.
Recommendations and Outlook The sediment contact test withMyriophyllum aquaticum is a valuable tool for the evaluation of the ecotoxicological risk potential of waters and sediments. It should become a
complement to a standardised test battery generally used for the assessment of sediment toxicity. 相似文献
19.
Short- and long-term effects of heavy metals on phosphatase activity in soils: An ecological dose-response model approach 总被引:7,自引:0,他引:7
Summary The aim of this study was to provide manageable data to help establish permissible limits for the pollution of soil by heavy metals. Therefore the short-and long-term effects of heavy metal pollution on phosphatase activity was studied in five different soil types. The results are presented graphically as logistic dose-response curves. It was possible to construct a curve for sand and silty loam soil but it was more difficult to establish a curve for sandy loam and clay soil and nearly impossible (except for Cu) for peat. The toxicity of the various metals can be compared on the basis of mmol values. In clay soils, for Cd, Cr, Cu, and Zn, the 50% effective ecological dose (ED50) values were comparable (approximately 45 mmol kg–1), but the ED10 values were very different, at 7.4, 41.4, 15.1, and 0.55, respectively. At the ED50 value, toxicity did not decrease with time and, in sandy soils, was approximately 2.6 mmol kg –1 dry soil for Cd, Cu, and Zn. In four out of five soils, the Cd toxicity was higher 1.5 years after the addition of heavy metal salts than after 6 weeks. Toxicity was least in the sandy loam, silty loam, and clay soil, and varied in general between 12 and 88 mmol kg–1. In setting limits, the criteria selected (no-effect level, ED10 or ED50) determine the concentration and also the toxicity of the sequence. It is suggested that the data presented here could be very useful in helping to set permissible limits for heavy metal soil pollution. 相似文献
20.
Mercè Llugany Roser Tolrà Sandra Raquel Martín Charlotte Poschenrieder Juan Barceló 《植物养料与土壤学杂志》2013,176(6):851-858
Glutathione (GSH) and phenolics play an important role in plant defense against metal‐ion toxicity. The antioxidant activity and metal‐binding capacity of these compounds can account for the protective effects. In contrast to animal‐cell models, however, the possible interplay among these substances in stress defense of plants is poorly investigated. This study compares the influence of cadmium (Cd) on the profiles of both soluble phenolics and GSH in shoots of different Thlaspi and Noccaea species: two ecotypes of the nonhyperaccumulator T. arvense differing in Cd resistance (ecotype Aigues Vives, Cd‐sensitive, and ecotype Jena, Cd‐resistant) and two Cd‐tolerant Cd‐Zn hyperaccumulators N. praecox and N. caerulescens (formerly Thlaspi praecox and T. caerulescens). To reveal the possible influence of Cd‐induced sulfur (S) shortage on the stress response, plants receiving normal S concentrations (500 μM MgSO4) and plants treated with surplus S (500 μM MgSO4 + 500 μM K2SO4) were analyzed. Our working hypothesis was that species differences in tolerance to high tissue Cd concentrations should be reflected by differences in endogenous levels of GSH and phenolic compounds. The results reveal clear species‐dependent differences in both the constitutive patterns and the Cd‐ and S‐induced changes in shoot concentrations of GSH and phenolics. However, no simple relationship between these shoot concentrations and Cd accumulation and tolerance can be established. 相似文献