辽河流域小麦白粉病综合治理体系

在田间,通过不同时期人工接种小麦条锈病菌和施用杀菌剂三唑酮的组合,测定小麦叶内三唑酮及其代谢产物三唑醇含量对病害相对侵染几率,潜育期,病斑扩展,产孢面积及传染期等组分的定量影响。结果表明,施药后不同批次接种,在一定时间内,麦叶内药剂可降低病害相对侵染几率并延长其潜育期;接种后施药在一个潜育期内,药剂可使病害潜育期提早。     

超高效液相色谱-串联质谱测定氟唑菌苯胺在小麦植株中的内吸传导特性

建立了超高效液相色谱-串联质谱（UPLC-MS/MS）测定氟唑菌苯胺在小麦植株中内吸传导特性的方法;定量分析了在小麦根部和叶部施药2种处理方式下氟唑菌苯胺进入植株后的分布和累积情况。植株样品前处理采用QuEChERS法,在反相色谱柱C18（100 mm × 2.1 mm, 1.8 μm）上,以0.1%甲酸水和乙腈为流动相,利用梯度洗脱,正离子电离（ESI+）,采用多反应离子监测模式（MRM）进行定性和定量。用基质匹配标准溶液外标法定量。结果表明:在0.5~100 μg/L内,氟唑菌苯胺的质量浓度与对应的峰面积间线性关系良好,线性回归方程为y = 12 808.4x + 308.518（r = 0.999 8）。在0.005、0.05和0.1 mg/kg添加水平下,氟唑菌苯胺在小麦植株中的回收率为92%~126%,相对标准偏差为0.50%~9.1%;以3倍信噪比计算,方法检出限为0.037 μg/kg;最低添加浓度为0.005 mg/kg。研究结果表明,氟唑菌苯胺于小麦植株根部施用后,可迅速在根部吸收并向茎部传导,且随处理浓度增大,药剂在不同部位的累积量增加;随处理后时间延长,药剂在不同部位的累积表现为先快速吸收而后缓慢平衡。其中以0.01 mg/L氟唑菌苯胺经根部施药2 h后,药剂在根、茎和叶中含量分别为10.4、0.6和0.3 μg/kg;氟唑菌苯胺经叶部单叶片施药后,亦可快速被叶片吸收,并可跨叶传导至其他叶片,进而在茎部和根部累积。随处理后时间延长,施药叶片药剂快速下降并达到平衡,其他植株部位药剂快速累积并达到平衡。其中以200 mg/L的氟唑菌苯胺经第2片叶施用20 μL,2 h后氟唑菌苯胺在根和茎中的含量分别为109.0和148.0 μg/kg,在第3片叶和旗叶中的含量分别为904.0和112.6 μg/kg。     

五种杀菌剂在水稻上的吸收与传导性能研究

茎叶喷雾是当前化学农药最常用的施药方式,但是存在着农药蒸发飘移、弹跳碎裂、因过度铺展而脱靶流失等缺陷,导致农药利用率低。通过研究农药在植物体内的吸收及传导性能,选择合适的农药研发根部施药的剂型与技术,能够降低环境因素对农药有效成分的不利影响,并通过农药的缓慢释放与剂量调控维持更长时间的药效,从而有效提高农药利用率。本研究以室内营养土和营养液两种模式培育的水稻为模式作物,研究了三环唑、噻呋酰胺、己唑醇、氟环唑和嘧菌酯5种不同类型的杀菌剂在水稻苗期植株中的吸收与传导行为。结果表明,这5种杀菌剂均可以被水稻幼苗根系吸收并向上传导,但效率存在差异。在营养土和营养液培养条件下,水稻幼苗根部的三环唑含量在4 h~2 d内明显高于茎叶部,施药5 d后三环唑在水稻中的转运因子值均大于1,说明三环唑具有良好的向上传输性能,而其他农药向上传输的能力较差。相比其他4种农药,三环唑更适合加工成根部施用的剂型,更易于通过水稻根部吸收后向上传输与分布,以有效防控茎叶部病害。该结果可为根部施用的药剂研发提供思路,为农药根部施药技术的发展提供指导。     

呋喃丹一次根区施药防治连晚二至四代褐稻虱适期探讨

呋喃丹内吸剂农药作为根区施药防治多种农业害虫较之目前常规用法有其许多优点,而引起国内外人们的重视。呋喃丹颗粒剂根区施药是把呋喃丹拌泥做药球深施到植株根部,通过根部吸收,再由植株中的输导组织把药剂自下而上输送到植株各部。因此,根区施药至呋喃丹农药出现在褐稻虱取食部位——植株基部叶鞘内,要有一定的时间。为了探索呋喃丹一次根区施药防治连晚二至四代褐稻虱的适期,我们进行了试验。     

三唑酮、三唑醇对小麦纹枯病菌形态和生理的影响

 小麦纹枯病菌(Rhizoctonia cerealis)在加入三唑酮(Triadimefon)或三唑醇(Triadimenol)的培养液中生长时,菌丝形态和生理发生明显的改变。菌丝畸形,表现为细胞肿大,细胞分隔处菌丝缢缩;药剂处理后,等量菌丝的麦角甾醇含量下降,1、5μg/ml的三唑酮和三唑醇处理,麦角甾醇含量比对照减少45.155.9%和27.5、48.9%;菌丝在药剂处理后,电解质渗漏增加,5μg/ml药剂处理一小时后,三唑酮组的菌丝之细胞电解质渗漏达2.58%,三唑醇组的渗漏为2.19%,空白对照组仅为0.65%。本研究结果表明,三唑酮、三唑醇对小麦纹枯病菌具有直接的伤害作用。     

高效液相色谱法研究啶菌噁唑(SYP-Z048)在番茄幼苗中的内吸传导特性

为明确啶菌噁唑(SYP-Z048)在植物体内的吸收传导特性及其在植物根部的吸收方式,于番茄幼苗根部或叶部施药后,采用高效液相色谱法(HPLC)分别测定了啶菌噁唑在根、茎、叶中的积累量;向含啶菌噁唑的培养液中分别添加羰基氰-间-氯苯腙、葡萄糖或色氨酸,以及在不同温度和pH条件下,分别测定了番茄幼苗根部对啶菌噁唑的吸收量及地上部分药剂积累量的变化。结果表明:50、100和200 mg/L啶菌噁唑处理番茄幼苗根部2 h后,在根部和茎部检测到目标药剂的含量分别为78.8、208.0、283.7μg/(g FW)和0.2、6.9、10.3μg/(g FW);16 h后,100 mg/L以上浓度处理组药剂可到达植株叶部;于中部叶片施加≥500 mg/mL的啶菌噁唑后72~124 h内,虽然在茎中未检测到药剂,但在根和上、下部叶片中均可检测到,表明药剂可在叶间传导转运至整个植株。不同浓度的羰基氰-间-氯苯腙、葡萄糖和色氨酸,以及低温条件和pH值等因子对番茄幼苗根部吸收药剂量和地上部分药剂积累量的影响与对照相比均无显著差异。研究表明,啶菌噁唑在番茄植株体内具有明显的向顶传导性及一定的向基传导性,同时其内吸传导过程以被动吸收占主导。     

吲哚乙酸引导下三唑醇在大豆植株中的传导与积累研究初报

将吲哚乙酸与三唑醇发生酯化反应后生成的吲哚乙酸三唑醇酯 ,在0.5 mmol/L浓度下水培和喷雾处理6~8叶期大豆植株,同时以相同浓度的三唑醇及其与吲哚乙酸的混合物为对照,色谱法测定不同时间植株不同部位吲哚乙酸三唑醇酯和三唑醇的含量。结果表明,与对照相比,吲哚乙酸三唑醇酯在大豆中具有明显的双向传导和向根部积累的特点。喷雾处理后,在12~60 h之间内吸量和根部积累量均出现最大值。     

新三唑类化合物P-4对小麦叶锈菌活体生物活性的研究

新合成的３２个１，２，４－三氮唑类似物在小麦叶锈病上活体生物活性研究表明，该类化合物对小麦叶锈菌有不同程度的生物活性。其中有１０个化合物的生物活性较为明显。这些化合物的化学结构和生物活性均未见报道。本文以２，２－二甲基－６－对溴苯氧基－４（１，２，４－三唑－１－基）己酮－３为例，在浓度１０μｇ／ｍｌ以上时对小麦叶锈菌活性达１００％。施药方法以叶面喷雾效果较好。高于标药剂三唑酮，但比烯唑醇差。残效期与三唑酮相似，内吸传导低于三唑酮。     

QuEChERS-超高效液相色谱-串联质谱法测定6种典型农药及3种代谢物在黄瓜中的残留消解动态

建立了超高效液相色谱-串联质谱(UPLC-MS/MS)同时检测黄瓜中多效唑、戊唑醇、丙硫菌唑、苯醚甲环唑、三唑酮、丁氟螨酯及3种代谢物B-3、三唑醇和CGA205375残留的分析方法,并采用该方法研究了6种农药不同施药剂量下在黄瓜中的消解动态.样品前处理采用QuEChERS方法,经乙腈提取,以N-丙基乙二胺(PSA)和...     

防治橡胶树褐根病0.5%戊唑醇膏剂的研制

由木层孔菌属有害层孔菌Phellinus noxius Corner引起的褐根病是我国橡胶树的主要根部病害之一。生产上常用挖隔离沟和灌根施药方式进行防治,但其耗费人力物力,防治成本高。为了寻求经济高效且环保的新技术,本研究通过对不同杀菌剂、填料、增稠剂、渗透剂和保湿剂进行筛选,制备了一种防治橡胶树褐根病的膏剂。随后,通过对外观、附着性、黏度、pH值、稳定性、成膜性及固含量流失率等性能指标的综合评价,确定了膏剂的最佳配方为：0.5%(质量分数,余同)戊唑醇、20%纳米硅藻土、2%羧甲基纤维素钠、6%乌迪尔树皮穿透剂、5%凡士林、5%棕榈油、5%乙二醇,余量为水。制备的膏剂为乳白色黏稠状,呈弱碱性,附着性强,黏度高,冷热储合格,成膜薄且有韧性,膜的固含量流失率为13.95%,耐雨水冲刷能力强。0.5%戊唑醇膏剂经过橡胶植株茎基部施药,通过气相色谱-串联质谱(GC-MS/MS)结合QuEChERs法检测橡胶根中戊唑醇的含量。结果表明,施药后24 h即可在植株根部检测到戊唑醇,96 h含量达到5.49 mg/kg,说明戊唑醇能穿透茎部树皮向下传导至根部。综上所述,膏剂剂型的研制为橡胶树褐根病的...     

Effect of triadimefon and triadimenol on growth of various plant species as well as on gibberellin content and sterol metabolism in shoots of barley seedlings

The fungicides triadimefon and triadimenol markedly reduced growth of coleoptiles, primary leaves, and roots of barley seedlings when grown for 7 days in petri dishes in the dark. The addition of gibberellins (A₁, A₃, A₄, A₇, A₉) alleviated growth retardation of primary leaves and coleoptiles induced by the fungicides. While fungicide-induced growth retardation of the shoots was partly relieved by kinetin, IAA did not show an alleviating activity. Triadimefon and triadimenol also substantially retarded the elongation of shoots of tomato and cotton plants and simultaneous application of GA₃ nullified the retardation. The fungicides only slightly interfered with both α-amylase production of intact germinating barley seed and the GA₃-induced α-amylase synthesis in barley endosperm. On the other hand, extracts of triadimefon- and triadimenol-treated shoot tissue of 10- to 12-day-old barley plants contained substantially lower gibberellin-like activity than control shoots. Both compounds also interfered in sterol metabolism of shoots of barley seedlings when compared to control plants, treatment resulted in lower amounts and altered proportions of C-4,4-desmethyl sterols. While both fungicides inhibited synthesis of C-4,4-desmethyl sterol fraction, sterols possessing C-4 and C-14-methyl groups were accumulated. It is assumed that triadimefon and triadimenol interfere in gibberellin and sterol biosynthesis in barley seedlings by inhibiting oxidative demethylation reactions.     

Control of loose smut (Ustilago nuda and U. tritici) infections in barley and wheat plants by foliar application of triadimefon

Foliar application of the broad-spectrum systemic fungicide triadimefon to loose smut-infected plants of wheat and barley produced a marked curative effect. Triadimefon was particularly effective when applied at the beginning of and during stem extension. In addition to reducing percentage plant infection, foliar application of this fungicide (particularly prior to flag leaf emergence) resulted in an increased proportion of infected ears which were only partially smutted. The curative effect of these early fungicide applications resulted in significant yield increases, as a consequence of increased grain number per m². Application of triadimefon to crops at ear emergence had no significant effect on percentage plant infection but resulted in lower levels of re-infection following artificial or natural inoculation of healthy ears, apparently as a result of a protectant effect of fungicide residues on or in the ovaries.     

Exogenous application of triadimefon affects the antioxidant defense system of Withania somnifera Dunal

Triadimefon is a triazole derivative, which have plant growth regulator properties. However, the influential mechanism of triadimefon on medicinal plants like Withania somnifera is not much studied. In the present investigation, the effects triadimefon at 10 mg L⁻¹ on the germination, early seedling growth, photosynthetic pigments, non-enzymatic antioxidant contents and activities of antioxidant enzymes were studied in W. somnifera Dunal plants. The germination percentage was not much affected by treatments and early seedling growth was reduced in terms of shoot length and leaf area but root length got increased with a concomitant enhancement in chlorophyll contents. The non-enzymatic antioxidants like ascorbic acid, reduced glutathione and α-tocopherol were increased in all parts (root, stem and leaf) of the seedlings. Triadimefon treatment caused an increase in the activities of antioxidant enzymes like superoxide dismutase, peroxidase, polyphenol oxidase and catalase. From our results it can be concluded that, the triadimefon can be used as a potential tool to enhance the antioxidant potential in medicinal plant W. somnifera.     

Photolysis,metabolism and other factors influencing the performance of triadimefon as a powdery mildew fungicide

Triadimefon, 1-(4-chlorophenoxy)-3,3-dimethyl-1-( 1,2,4-triazol-1-yl)butanone, applied at low dosage rates to leaves of marrow, apple or barley plants gave effective control of the appropriate powdery mildew fungi. The compound appeared to be systemic and to have considerable vapour-phase activity. In marrow plants, up to 56% of triadimefon was metabolised to a mixture of two corresponding diastereoisomeric secondary alcohols. The mixture was identical with that obtained by chemical reduction of triadimefon. This mixture was also a very effective systemic fungicide and active in the vapour-phase. Triadimefon was also reduced when incubated with Aspergillus niger but this was important only in shake culture. In replacement culture experiments, mycelial mats of this fungus converted the compound into a different metabolite, its isopropyl analogue. This may have resulted from participation of triadimefon in the C-4 demethylation processes involved in fungal biosynthesis of ergosterol. Photolysis caused cleavage of the C-1 to triazole bond liberating 1,2,4-triazole, 4-chlorophenol and 4-chlorophenyl methyl carbonate, all of which were non-fungitoxic. The importance of this photolysis in the in-vivo situation is discussed.     

Effects of triadimefon on the ultrastructure of rust fungi infecting leaves of wheat and broad bean (Vicia faba)

The effect of triadimefon on the fine structure of Uromyces vicia-fabae infecting leaves of broad bean, and brown rust caused by Puccinia recondita infecting wheat leaves, was studied using transmission electron microscopy. Changes were induced in intercellular mycelia following both root and leaf application of the fungicide. Incomplete and multiperforate septa occurred, and extensive wall thickening was found, often almost completely blocking the hyphae. Triadimefon vapour was shown to have a similar effect on intercellular hyphae of P. recondita as did direct application. The changes are discussed in relation to the mode of action of triadimefon and its effect on sterol biosynthesis.     

农药在植物中的内吸和传导行为与施药技术研究进展

农药的施用方式和施用效果与其在植物中的内吸和传导行为密切相关.农药在植物表面和内部的内吸和传导行为,不仅与其自身理化性质有关,还受植物种类、生长期、生长条件及施药方式等因素的影响.研究农药在植物体内的内吸和传导行为及其影响因素,对于选择合适的施药技术及提高农药利用率具有重要的指导意义.本文综述了农药在植物体内的内吸和传...     

THE SELECTIVE ACTION OF PICLORAM IN RED MAPLE AND WHITE ASH

Summary. White ash ( Fraxinus americana L. ) trees, 2 years of age, treated continuously with 10 ppm picloram (4-amino-3,5,6-trichloropicolinic acid) in nutrient culture were only slightly injured after 4 weeks whereas red maple ( Acer rubrum L.) trees were killed after only 2 weeks treatment.
When the roots were exposed to 10 ppm ¹⁴C-picloram, the rate of root uptake, acropetal translocation in the stem, and accumulation in the leaves was much lower in the susceptible red maple than in the tolerant white ash. The foliar penetration and translocation of ¹⁴C-picloram applied to the leaves was very slight but similar in both species. Although a radiolabelled picloram metabolite was isolated from plant extracts, it was formed at equal rates in both species.
It was concluded that the tolerance of white ash was not related to lower rates of picloram uptake or faster rates of picloram detoxication. It was postulated that the high susceptibility of red maple was due to a blockage of the xylem by picloram which caused death by a dessication of the leaves and upper stems.
Action sélective du piclorame sur Fraxinus amerieana L. et Acer rubrum L.     

Spray application factors and plant growth regulator performance: II. Foliar uptake of gibberellic acid and 2,4-D

Effects of droplet size and carrier volume on foliar uptake and translocation of gibberellic acid (GA₃) and 2,4-D were investigated. Simulated spray droplets were applied to primary leaves of 10-day-old Phaseolus vulgaris (cv Nerina) in droplet sizes and carrier volumes ranging from 0.5 to 10 μl and 10 to 200 μl per leaf, respectively. Doses of GA₃ (2 μg per leaf) and 2,4-D (100 μg per leaf) were held constant. Total uptake of GA₃ approached a penetration equilibrium within 24 h after application, but uptake of 2,4-D continued to increase. Decreasing droplet size and/or increasing carrier volume increased GA₃ and 2,4-D uptake. Translocation to stem and roots was positively related to total uptake. A positive linear relationship between the logarithm of the total droplet/leaf surface interface area and 2,4-D uptake or translocation was found, but for GA₃ this relationship was quadratic. Potential mechanisms of the effects of spray application factors on foliar uptake are discussed. © 1999 Society of Chemical Industry     

Preparations for the treatment of pruning wounds

Benodanil, triadimefon or triadimenol, prepared as solutions (30 g litre^?1) in a mixture of N-methyl-2-pyrrolidone and xylene(1+ 9 by volume), or benodanil, prepared by diluting an emulsified concentrate with water, were applied to the surface of stumps produced by removing branches from apple trees. The active ingredients penetrated in fungitoxic amounts at least 6 cm below the wound surface, except when diluted benodanil e. c. was used. No such penetration occurred when the stumps were treated with acrylic paints containing the same ingredients. Triadimefon and triadimenol persisted within the wood for at least 273 days. No treatment inhibited callus formation but none appeared to enhance it. There were more saprophytic fungi in samples taken from treated than from untreated stumps, and the number of microorganisms present in the wood decreased with distance from the wound surface. Only one basidiomycete fungus was present in wood samples taken 273 days after treatments were carried out.