液相色谱与气相色谱法测定小麦中丙环唑(Propiconazole)的残留

用高压液相色谱紫外检测法,在波长229纳米处测丙环唑;气相色谱则采用电子捕获检测器。两法均以甲醇作样品的浸提溶剂,用液-液分配进行初步净化。如用气相色潜电子捕获检测器,需用氧化铝柱层析进一步净化。两法的回收率都大于80％。气相色谱法对样品的最低检出浓度为O.02毫克/公斤,液相色谱法则为0.4毫克/公斤。

Responses of Winter Wheat to Herbicide-Fungicide Tankmixes

Tankmixing herbicides with fungicides could improve production efficiency and reduce application costs. A total of six field trials were conducted from 2012 to 2014 in Ontario to study the tolerance of winter wheat to herbicide (fenoxaprop-p-ethyl/mefenpyr, prosulfuron + bromoxynil and fluroxypyr + MCPA ester) plus fungicide tankmixes (pyraclostrobin/metconazole, tri-floxystrobin/propiconazole, azoxystrobin/propiconazole and picoxystrobin) applied alone and as a tankmix. At 1 WAT, fenoxaprop-p-ethyl/mefenpyr applied alone or in tankmix with tri-floxystrobin/propiconazole or azoxystrobin/propiconazole fungicides caused minimal visible injury (up to 1.3%) in winter wheat but caused no significant injury when applied as a tankmix with pyraclostrobin/metconazole or picoxystrobin fungicides. There was no effect on visible injury in winter wheat with other herbicide and fungicide tankmixes. Fenoxaprop-p-ethyl/mefenpyr applied alone with no fungicide reduced winter wheat height 3% but had no adverse effect on height when tankmixed with fungicides evaluated. Prosulfuron + bromoxynil or fluroxypyr + MCPA ester herbicides applied alone with no fungicide or tankmixed with pyraclostrobin/metconazole, tri-floxystrobin/propiconazole, azoxystrobin/propiconazole and picoxystrobin fungicides had no adverse effect on winter wheat height. There was no adverse effect of herbicide plus fungicide treatments on winter wheat yield. Co-application of fenoxaprop-p-ethyl/mefenpyr, prosulfuron + bromoxynil and fluroxypyr + MCPA ester herbicides with pyraclostrobin/metconazole, tri-floxystrobin/pro- piconazole, azoxystrobin/propiconazole and picoxystrobin fungicides could provide winter wheat growers with a single-pass treatment for the control of weeds and diseases.

Photochemical Decomposition of Pesticide Chemicals in Aerosol Particles and Thin Films Relevant to Environmental Conditions

Contamination of the environment by pesticides is the inevitable aftermath of plant protection, and a substantial portion of pesticide pollutants exists in the form of aerosol particles levitated in the air and deposited on plants, and as the pesticide residues （thin films） on the surface of plant leaves. The sunlight photolysis could be the resource for the accelerated photochemical decomposition of pesticide compounds to minimize the long-term environmental contamination. The rates of photochemical decomposition of pesticide chemicals propiconazole （commercial formulation Tilt） and haloxyfop-ethoxyethyl （Zellek） were measured in particles of 0.12-1.3 μm in diameter and in films 0.04-0.2 μm thick. A specific polyaromatic sensitizer Shirvanol was used to induce accelerated decomposition of the above pesticide particulates under both the solar radiation and the artificial UV light. It was established that propiconazole decomposes by the sensitized photo-oxidation only, but haloxyfop-ethoxyethyl reacts in both the oxygen （air） and oxygen-free mediums via both the direct and sensitized reactions. The photochemical mechanisms are hypothesized and argued for the oxidative and non-oxidative decompositions. The haloxyfop-ethoxyethyl （Zellek） residues lbrmed on foliage upon pesticide treatments of agricultural fields would essentially decompose under sunlight via a direct photoreaction in 4-6 weeks, but the propiconazole （Tilt） contaminants probably need more time.

Application Effect of Pesticide Synergist‘Jijian' on Wheat Stripe Rust

The aim of this study is to clarify the application effect of pesticide decrement synergist ＇ Jijian＇ on wheal stripe lUSt. Sampling investigation, randomized block design and statistic analysis were carried out to find out the field efficacy of adding ＇ Jijian＇ to triadimefon WP and propiconazole EC on controlling wheat stripe rust. The results showed that during the epidemic period of stripe rust, the control effects on the 7^th and the 19^th d reached more than 93% and 100% , respectively, by the application of 15% triadimefon WP of 1 200 g/hm^2 and 25% propiconazole EC of 600 mlhm^2 , respectively for 2 times ; when 15% triadimefon WP of 840 g/hm^2 ＋ ＇ Jijian＇ of 225 g/hm^2 or 25 % propiconazole EC of 420 mlhm^2 ＋ ＇ Jijian＇ of 225 g/hm^2 were applied （ adding ＇ Jijian＇ and reducing the dosage of the 2 pesticides by 30% ） , the control effect on the 7^th d was 89.4% and 91.7% , respectively, while the control effect on the 19a＇ d was 99.8 - 100% ; when 15% triadimefon WP of 720 - 600 g/hm^2 ＋ ＇ Jijian＇ of 225 g/hm^2 or 25% propiconazole EC 360 - 300 mlhm^2 ＋ ＇ Jijian＇ of 225 g/hm^2 were applied （ adding ＇ Jijian＇ and reducing the dosage of the 2 pesticides by 40% - 50% ） , the control effect on the 7a＇ day reached more than 78.0% , while the control effect on the 19^th day was 97.7% - 99.8%. There was no significant difference on the control effect at the 7^th d between the treatments using the 2 pesticides alone and the treatments adding ＇ Jijian＇ and reducing the dosage of the 2 pesticides by 30%, but all had significant differences from the treatments adding ＇ Jijian＇ and reducing the dosage of the 2 pesticides by40% -50%. There was no significant difference on the control effect of the 19^th d among different treatments. Therefore, if the disease is not serious, the application of ＇ Jijian＇ can reduce the application amounts of pesticides by 40% -50%, that is, 15% triadimefon WP of 720 -600 g/hm^2 ＋ ＇ Jijian＇ of 225 g/hm^2 or 25 % propiconazole EC of 360- 300 ml/hm^2 ＋ ＇ Jijian＇ of 225 g/hm^2, which is helpful to reduce the pesticide application amounts and pesticide residue pollution, and save the control costs.

Fixation Property of Copper Triazole Wood Preservatives

According to AWPA E11-2006 standard,copper fixation rates of several copper-based formulations,such as ammoniacal copper,amine copper,and ammoniacal-ethanolamine copper,as well as alkaline copper quaternary(ACQ),were tested and compared in this paper.And the fixation rates of tebuconazole(TEB) and propiconazole(PPZ) in several formulations,such as copper azole,emulsified type and solvent type,were also compared.The determination of copper content in the leachate was analyzed by atomic absorption spectrom...

Alterations in sucrose metabolizing enzyme activities and total phenol content of Curcuma longa L. as affected by different triazole compounds

Changes in the sucrose metabolism of Cur-cuma longa L.plants were studied under treatment with different triazole compounds viz.,triadimefon(TDM)and propiconazole(PCZ).Plants were treated with TDM at 15mg/L and PCZ at 10mg/L separately by soil drenching on 80,110,and 140 days after planting(DAP).The plants were harvested randomly on 90,120,and 150DAP to determine the effect of both the triazoles on sucrose metabolizing enzymes and phenol content.The sucrose metabolism was studied by analyzing sucrose metaboliz-ing enzymes like sucrose synthase and sucrose phosphate synthase.All the analyses were assayed in leaves and tubers of both control and treated plants.It was found that both of the triazole compounds had profound effects on these parameters.