灭菌促长剂防治柑橘贮藏期病害的药效试验

介绍了采用菌溶生长速率法测定灭菌促长剂对柑橘蒂病菌的ＥＣ５０为０．６６ｍｇ／ｋｇ,采用９００ｍｇ／ｋｇ药液浸泡柑橘２－３ｍｉｎ后风干,套袋,常温保存３０、６０、８０ｄ后的防治效果分别为９１．７４％８９．５５％和８３．０５％,明显优于多菌灵,说明灭菌促长剂可溶性粉剂对柑橘贮藏期病害有良好的防治效果。     

10%烯啶虫胺AS对柑橘粉虱室内毒力测定和田间药效试验

[目的]探明烯啶虫胺对柑橘粉虱的毒力和防治效果。[方法]采用药膜法测定烯啶虫胺对柑橘粉虱室内毒力,在田间进行小区药效试验。[结果]烯啶虫胺对柑橘粉虱成虫的LC50值为1.89 mg/kg;田间药效试验中,10%烯啶虫胺AS 100 mg/L对柑橘粉虱药后1、3 d防效分别为98.75%、96.04%。[结论]烯啶虫胺对柑橘粉虱有较高的活性和较好的防治效果。     

高效氯氟·噻虫嗪等6种药剂对柑橘木虱的防治效果

[目的]筛选防治柑橘木虱的高效低毒药剂,为生产上推广应用提供科学依据。[方法]依照田间药效试验准则,进行高效氯氟·噻虫嗪等6种药剂对柑橘木虱的田间防治效果评价。[结果]施药1次后15 d,22%高效氯氟·噻虫嗪微囊悬浮-悬浮剂73.3 mg/kg、10%吡虫啉可湿性粉剂66.7 mg/kg和4.5%高效氯氰菊酯乳油45 mg/kg三个药剂处理对柑橘木虱的防治效果优良,平均防效分别为93.95%、91.14%和89.32%。[结论]上述3种药剂对柑橘木虱有较好的防治效果,建议在生产上推广应用。     

18%氟唑菌酰羟胺·苯醚甲环唑悬浮剂防治柑橘疮痂病田间防效

[目的]明确18%氟唑菌酰羟胺·苯醚甲环唑悬浮剂对柑橘疮痂病的防治效果,为生产上应用提供理论依据。[方法]依照杀菌剂田间药效试验准则进行田间药效试验。[结果]18%氟唑菌酰羟胺·苯醚甲环唑悬浮剂100、120 mg/kg处理对柑橘疮痂病的防治效果都在79%以上,且对柑橘树无药害。[结论]18%氟唑菌酰羟胺·苯醚甲环唑悬浮剂对柑橘疮痂病有较好的防治效果,建议使用剂量为100~120 mg/kg。     

26％螺虫乙酯·联苯菊酯悬浮剂对柑橘木虱的田间防效

[目的]评价26%螺虫乙酯·联苯菊酯悬浮剂对柑橘木虱的防治效果。[方法]参照农药田间药效试验准则进行试验。[结果]26%螺虫乙酯·联苯菊酯悬浮剂43.3、52、65 mg a.i./kg在药后7、14 d的田间防效均在90.93%以上,药后21 d,防效保持在93.59%~99.43%,表现出较好的防治效果、速效性和持效性,对柑橘无药害。[结论]建议在柑橘新梢抽发期,柑橘木虱低龄若虫始盛期,使用26%螺虫乙酯·联苯菊酯悬浮剂43.3~52 mg a.i./kg喷雾为宜。     

15%唑虫酰胺悬浮剂对柑橘木虱田间药效评价

[目的]明确15%唑虫酰胺悬浮剂对柑橘木虱的田间防治效果,为生产上应用提供科学依据。[方法]依照田间药效试验准则进行田间药效试验。[结果]15%唑虫酰胺悬浮剂37.5、42.86、50.0 mg a.i./kg在药后1、3、7 d的田间防效均达92.3%以上,药后14 d,防效仍保持在90.0%~99.8%,表现出较好的防治效果、速效性和持效性,对柑橘无药害。[结论]建议在柑橘新梢抽发期、柑橘木虱若虫初发生时,使用15%唑虫酰胺悬浮剂37.5~50.0 mg a.i./kg喷雾为宜。     

24%螺虫乙酯SC防治柑橘木虱、粉虱等4种主要害虫田间药效试验

[目的]为探明螺虫乙酯对柑橘主要害虫的防治效果,于2010年5—8月进行了柑橘粉虱、潜叶蛾、木虱、红蜘蛛的田间药效试验。[结果]24%螺虫乙酯SC 1000 mg/L对柑橘粉虱药后1、3 d的防效高于90.1%;1 000 mg/L对柑橘潜叶蛾药后4 d的防效低于30.2%;对柑橘木虱防效不稳定,在5—6月2次试验中,只有500 mg/L对柑橘木虱防效高(药后24 h防效>95%),在8月的试验中,333、500、1 000 mg/L药后1~15 d的防效均低于82%;500 mg/L对柑橘红蜘蛛药后1~22 d的防效为48.7%~93.9%。[结论]24%螺虫乙酯SC对柑橘粉虱、红蜘蛛防效好;对木虱防效不稳定;对潜叶蛾防效差。     

灭菌促长剂防治柑橘贮藏期病害的药效试验及安全性评价

柑橘果实采收后在贮藏过程中常发生多种病害,过去每年因此造成的损失率达20%～30%,严重的达60%以上〔1〕。一些传统的药剂如甲基托布津、多菌灵等在一定程度上控制了病害的发生〔2〕,但由于病原菌的抗性日益严重,寻求新的药剂已成为当务之急。灭菌促长剂可溶性粉剂是1995年开发成功的杀菌剂,已获得国家专利,其有效成分为多菌灵草酸盐〔3〕,本文拟将灭菌促长剂应用于防治柑橘贮藏期病害的试验研究。1　材料与方法1.1　实验材料柑橘在湖北农学院柑橘园采摘,品种为温州蜜桔;蒂腐病原菌(ＤｉｐｌｏｄｉａｎａｔａｌｅｎｓｉｓＥｖａｎｓ)系从病…     

新型杀虫剂氟吡呋喃酮对柑橘木虱的田间防效

[目的]评价氟吡呋喃酮对柑橘木虱的防治效果,为生产上应用提供科学依据。[方法]依照田间药效试验准则进行田间药效试验。[结果]17%氟吡呋喃酮可溶性液剂50、66.7、100 mg a.i./kg在药后3、7、14 d的田间防效均高于88.5%,甚至高达100%,至药后21 d,防效依旧高达98.4%~100%,表现出良好的速效性和持效性,与对照药剂21%噻虫嗪悬浮剂50.0 mg a.i./kg处理效果相当,对柑橘无药害。[结论]建议在柑橘新梢抽发期,柑橘木虱若虫初发生时,使用17%氟吡呋喃酮可溶性液剂50~100 mg a.i./kg喷雾为宜。     

唑胺菌酯与咪鲜胺混剂对柑橘炭疽病的药效试验

[目的]明确唑胺菌酯和咪鲜胺在防治柑橘炭疽病上的可混性。[方法]采用生长速率法测定唑胺菌酯与咪鲜胺复配制剂对柑橘炭疽病菌的室内毒力,并在田间进行制剂药效试验。[结果]唑胺菌酯与咪鲜胺5个供试混剂的共毒系数均大于120,表现为明显增效作用,其中以5∶1的配比抑菌效果最好;田间20%唑胺菌酯·咪鲜胺SC 200 mg/L剂量下对柑橘炭疽病的防治效果与25%咪鲜胺EC 333 mg/L相当,明显高于70%甲基托布津WP。[结论]20%唑胺菌酯·咪鲜胺SC对柑橘炭疽病具有良好的防治效果,且对柑橘生长安全。     

Effect of concentration, temperature, moisture, liming and organic matter on the efficacy of the nitrification inhibitors benzotriazole, o-nitrophenol, m-nitroaniline and dicyandiamide

Laboratory experiments were carried out to study the effect of various factors that affect the efficacy of the nitrification inhibitors, benzotriazole, o-nitrophenol, m-nitroaniline and dicyandiamide. In a Paleustalf, increasing concentrations of the inhibitors from 0 to 15 mg/kg soil prolonged the nitrification up to 60 days. Increase in temperature from 10 to 30°C decreased the efficacy of all four nitrification inhibitors (by 6–62% at 30 days). Benzotriazole was equally effective in soil moisture conditions ranging from 40 to 80% of the maximum water holding capacity of the soil (WHC). o-Nitrophenol and m-nitroaniline were more effective at 60% WHC, while the efficacy of DCD was more at 40% WHC. Addition of 1000 mg/kg soil of fresh organic matter reduced the efficacies of o-nitrophenol, m-nitroaniline and benzotriazole by 55, 65 and 22%, respectively while the reduction in the efficacy of dicyandiamide was non-significant. Liming an acidic soil (Kandiustalf) to change the pH from 5.4 to 8.3 decreased the efficacies of the nitrification inhibitors and decreased the ammonium content in the soil at 30 days from 55 to 9 mg/kg in case of o-nitrophenol and m-nitroaniline and from 53 to 35 mg/kg in case of benzotriazole and dicyandiamide.     

腈菌唑在小麦,土壤上残留与降解的动态试验研究

本试验为腈菌唑在辽宁、江苏两地的两年残留测定，作物为小麦。分析目标为麦粉、麦杆、青植株、土壤，四种试材分析方法的添加回收率均为７５％以上。１９９３年土壤的半衰期辽宁、江苏分别为２７．２天和２３．７天，小麦青植株的半衰期辽宁、江苏分别为２．１天和２．５天；１９９４年土壤的半衰期辽宁、江苏分别为２５．８天和３６．７天，小麦青植株的半衰期辽宁、江苏分别为４．３天和３．３天。试验施药剂量为２５毫克／公斤（２．５克／亩）及５０毫克／公斤（５．０克／亩）两种，在收获期小麦麦粉及麦杆中的残留量都低于参照的允许残留量０．１毫克／公斤及２．０毫克／公斤，安全间隔期为２０天。分析结果表明腈菌唑对小麦使用安全。     

唑螨酯对土壤呼吸作用和过氧化氢酶活性的影响

通过模拟实验研究了杀螨剂唑螨酯对土壤呼吸作用和土壤巾过氧化氢酶活性的影响。结果表明，唑螨酯对土壤的呼吸作用有一定的影响，用1mg/kg剂量处理，初期土壤呼吸作用表现为轻微的抑制，到第15d则恢复到与对照一致。用5、10mg／kg剂量处理，则在培养期间内一直处于被抑制状态。唑螨酯对土壤中过氧化氢酶的活性有一定影响但不显著，在试验期间内，低浓度处理（1、10mg／kg）呈现出轻微的抑制-激活-恢复过程，而高浓度处理（40、80mg／kg）则呈现出抑制-激活-抑制-恢复过程。实验结果表明，唑螨酯对土壤微生物影响较小，属于低毒或无实际危害的农药。     

Tall Larkspur Ingestion: Can Cattle Regulate Intake Below Toxic Levels?

Tall larkspur (Delphinium barbeyi) is a toxic forb often consumed by cattle on mountain rangelands, with annual fatalities averaging about 5%. This study examined the relationship between food ingestion and toxicity in cattle. Two grazing studies suggested that larkspur consumption above 25–30% of cattle diets for one or two days led to reduced larkspur consumption on subsequent days. We subsequently hypothesized that cattle can generally limit intake of larkspur to sublethal levels. This hypothesis was tested by feeding a 27% larkspur pellet in experiment 1. Cattle given a 27% larkspur pellet ad libitum showed distinct cyclic patterns of intake, where increased larkspur consumption on one or two days was followed by reduced (P < 0.025) consumption on the following day. The amount of larkspur (mean 2007 g/day; 17.8 mg toxic alkaloid/kg body wt) consumed was just below a level that would produce overt signs of toxicity. Experiment 2 was conducted to examine cattle response to a toxin dose that varied with food intake. Lithium chloride (LiCl) paired with corn ingestion was used as a model toxin, and we hypothesized that if increased (decreased) consumption was followed by a stronger (weaker) dose of LiCl, cattle would show a transient reduction (increase) in corn intake. There was no difference (P > 0.05) between controls and treatment animals at the 20 or 40 mg LiCl/kg dose in the percentage of corn consumed, but the 80 mg LiCl/kg dose induced a cyclic response (mean 46%) compared to intake by controls (mean 96%) (P < 0.001). At the 80 mg/kg dose, LiCl induced an aversion to corn; when corn intake decreased on subsequent days and LiCl dose also decreased, cattle responded by increasing corn intake and apparently extinguishing the transient food aversion. Experiment 3 was similar to the LiCl trial, except that tall larkspur was the toxin. Cattle responded to oral gavage of ground larkspur with distinct cycles; days of higher corn consumption were followed by one to three days of reduced consumption. Corn intake for controls was higher (P < 0.01) than for larkspur-treated animals (means 84 and 52%, respectively; day × treatment interaction P < 0.01). The threshold for toxic effects on corn intake was 14 mg toxic alkaloid/kg body weight. In conclusion, cattle apparently limit ingestion of some toxins so that periods of high consumption are followed by periods of reduced consumption to allow for detoxification. Cyclic consumption generally enables cattle to regulate tall larkspur consumption below a toxic threshold and allows cattle the opportunity to safely use an otherwise nutritious, but toxic, plant.     

氧化沟污泥膨胀控制技术研究

以实际氧化沟工艺污水处理厂为对象,研究了氧化沟污泥膨胀特性;以小试模拟试验系统为对象,分别研究了投加季铵盐、PAM和次氯酸钠以及调整运行工艺参数等对氧化沟污泥膨胀的控制效果。试验结果表明,实际污水处理厂的丝状细菌为微丝菌（Microthrix parvicell）;在连续投加50 mg/L的季铵盐2 d以后,污泥膨胀问题得到有效控制;用2 mg/L的PAM控制氧化沟污泥膨胀较适宜,较短的时间内即可有效控制;30 mg/g MLSS的次氯酸钠可以使处于膨胀状态的氧化沟系统快速得到控制;提高氧化沟的溶解氧含量和污泥负荷,有助于抑制污泥膨胀和丝状菌增殖。     

Perfluorodecanoic acid and lipid metabolism in the rat

Alterations in lipid metabolism were axamined in adult male Sprague-Dawley rats seven days after a single intraperitoneal injection of perfluorodecanoic acid (PFDA; 20, 40 or 80 mg/kg). Because PFDA treatment caused a dose-related reduction in feed intake, the response of vehicle-treated rats pair-fed to those receiving PFDA was monitored to distinguish direct effects of the perfluorinated fatty acid from those secondary to hypophagia. Carcass content of lipid phosphorus and free cholesterol decreased in dose-dependent fashion in both PFDA-treated and pair-fed rats. Carcass triacylglycerols diminished in a similar manner, yet PFDA-treated rats at each dose had a higher concentration of neutral acylglycerols than their vehicle-treated, pair-fed counterparts. In vehicle-treated, pair-fed rats at the 80 mg/kg dose level, lipid phosphorus and free cholesterol as a proportion of carcass fat increased, whereas the share of the triacyl-glycerols declined. Because of the higher concentration of triacylglycerols in the carcass of rats treated with 80 mg/kg PFDA, enrichment of lipid phosphorus and free cholesterol in carcass fat was less than in their pair-fed partners. The amount of lipid phosphorus and free cholesterol per hepatocyte was similar in both PFDA-treated rats and their pair-fed partners. Liver triacyl-glycerols were markedly increased in PFDA-treated rats. A similar but less extensive augmentary effect of PFDA on hepatic esterified cholesterol was found. Concentration of triacylglycerols in plasma was not elevated in PFDA-treated rats, in spite of hepatic accumulation of esterified compounds. Also, the plasma level of free fatty acids and 3-hydroxybutyrate was similar in all treatment groups, including those receiving PFDA. Thus, the administration of PFDA appears to divert fatty acids from oxidation toward esterification in the liver.     

Dose-Dependent Effects of Resveratrol on Cisplatin-Induced Hearing Loss

Previous preclinical studies have demonstrated the otoprotective effects of resveratrol (RV) at low doses. This study aimed to investigate the dose-dependent effects of RV in rats with cisplatin (CXP)-induced hearing loss. Sprague-Dawley rats (8-weeks old) were divided into six treatment groups (n = 12/group) and treated as follows: control, 0.5 mg/kg RV, 50 mg/kg RV, CXP, 0.5 mg/kg RV + CXP), and 50 mg/kg RV + CXP groups. CXP (3 mg/kg) was intraperitoneally injected for 5 days. RV (0.5 or 50 mg/kg) was intraperitoneally injected for 10 days from the first day of CXP administration. Auditory brainstem response (ABR) thresholds were measured before and within 3 days at the end of the drug administration. Cochlear tissues were harvested, and the outer hair cells were examined using cochlear whole mounts. The mRNA expression of NFκB, IL6, IL1β, and CYP1A1, and protein levels of aryl hydrocarbon receptor (AhR) and cytosolic and nuclear receptor for advanced glycation endproducts (RAGE) were evaluated. The ABR threshold increased in the 50 mg/kg RV and CXP groups at 4, 8, 16, and 32 kHz. The 0.5 mg/kg RV + CXP group demonstrated decreased hearing thresholds at 4 and 32 kHz compared to the CXP group. Cochlear whole-mount analysis revealed loss of outer hair cells in the 50 mg/kg RV and CXP groups and partial prevention of these cells in the 0.5 mg/kg RV + CXP group. The mRNA expressions of NFκB, IL6, and IL1β were increased in the 50 mg/kg RV and CXP groups compared to the control group. In contrast, these levels were decreased in the 0.5 mg/kg RV + CXP group compared to the CXP group. The mRNA expression of CYP1A1 was increased in the CXP group, while it was decreased in the 0.5 mg/kg RV + CXP group compared to the control group. The protein levels of AhR and cytosolic RAGE decreased in the 0.5 mg/kg RV group. Low-dose RV had partial otoprotective effects on CXP ototoxicity. The otoprotective effects of RV may be mediated through anti-oxidative (CYP1A1 and RAGE) and anti-inflammatory (NFκB, IL6, and IL1β) responses. High-dose RV exerted an inflammatory response and did not ameliorate CXP-induced ototoxicity.     

The Synergism of Biochemical Components Controlling Lipid Oxidation in Lamb Muscle

Lipid oxidation of M. longissimus lumborum in fresh or vacuum packaged (aged) lamb meat stored at 3 °C for 0 or 4 weeks, respectively and displayed under refrigerated conditions for a further 4 days was assessed by measuring the concentration of malondialdehyde (MDA) in meat using the thiobarbituric acid reactive substances procedure. The effects of vitamin E, heme iron and polyunsaturated fatty acids (n-6 and n-3) on lipid oxidation were examined. Results showed a strong positive relationship between heme iron, n-6 and n-3 fatty acids and lipid oxidation when vitamin E was below 2.95 mg/kg muscle. When lipid oxidation was related to vitamin E concentration and the other three variables, respectively, any increase in heme iron or n-6 or n-3 fatty acids concentration did not influence lipid oxidation. Management of diet to elevate muscle vitamin E concentration above 3.45 mg/kg muscle is beneficial to maintain the level of lipid oxidation below 2.4 mg MDA/kg muscle in meat stored for up to 4 weeks. This demonstrates that vitamin E concentration in muscle has a greater influence on controlling lipid oxidation in muscle tissues than do heme iron or polyunsaturated fatty acids.     

Effects of perfluorodecanoic acid onde novo fatty acid and cholesterol synthesis in the rat

Perfluorodecanoic acid (PFDA) is a peroxisome proliferator that causes a dose-dependent (20–80 mg/kg) increase in hepatic triacylglycerol and cholesteryl ester levels in the rat. We hypothesized that PFDA may cause an increase in thede novo synthesis of fatty acids and cholesterol in this species, which would explain observed effects. The incorporation of³H₂O into tissue lipids was examined 7 days after rats received vehicle or 20 or 80 mg/kg of PFDA. PFDA treatment decreased the rate of synthesis of cholesterol and fatty acids in the liver and in epididymal fat pad. At a PFDA dose (20 mg/kg) that decreasedde novo synthesis of fatty acids and cholesterol, there was no effect on the concentration of fatty acids and cholesterol in the liver, epididymal fat pads, and plasma. We conclude that PFDA induced fatty liver is due to either a decrease in the oxidation of fatty acids in the liver, or an impairment of triacylglycerol catabolism and/or export from the liver, and is not the result of an increase inde novo synthesis of fatty acids and cholesterol.     

氟菌唑及其代谢物在梨和土壤中的残留及安全使用评价

为了评价氟菌唑及其代谢物在梨和土壤中的残留动态和环境安全性,采用田间试验的方法,对氟菌唑及其代谢物在梨及土壤中的残留消解动态及其最终残留量进行了研究。消解动态试验结果表明:氟菌唑在梨中的半衰期为3.0~5.0 d,氟菌唑在土壤中的半衰期为10.1~13.9 d。最终残留量试验结果表明:35%氟菌唑可湿性粉剂285.7~428.6 mg/kg连续喷药2~3次,施药间隔期为10 d,药后14 d,土壤中残留量为0.020~0.051 mg/kg,梨中残留量为0.020~0.085 mg/kg。推荐35%氟菌唑可湿性粉剂在梨上使用安全间隔期为14 d。