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1.
为判断溴甲烷和硫酰氟对舞毒蛾不同虫态的杀灭效果,在25℃下,分别在经过气密性检测的熏蒸桶内投入16、20、24、32 g/m3的溴甲烷和40、56、72、88 g/m3的硫酰氟,熏蒸处理舞毒蛾卵、幼虫、蛹和成虫4.5h.结果表明,经过4.5h熏蒸,杀灭舞毒蛾卵、1龄幼虫、蛹和成虫的溴甲烷浓度分别为32、20、24和16 g/m3,杀灭上述虫态硫酰氟浓度分别为88、56、72和40 g/m3.本文结果表明,舞毒蛾卵为最耐受溴甲烷和硫酰氟熏蒸的虫态,在目前口岸实际熏蒸处理中应充分考虑熏蒸剂对舞毒蛾卵的杀灭效果. 相似文献
2.
溴甲烷对松木木质包装穿透性研究 总被引：3，自引：0，他引：3
25℃、48g/m3起始剂量条件下,溴甲烷熏蒸12h,熏蒸箱内溴甲烷浓度衰减率超过40%,而12h后到48h熏蒸结束时,溴甲烷衰减率小于5%。箱内溴甲烷CT值在6h达到200g.h/m3。溴甲烷对松木的穿透是顺着木纹进行的。在熏蒸48h内,无虫害木块内部各采样孔的溴甲烷浓度与箱内浓度无法达到平衡,15cm处CT值不足200g.h/m3;有虫害木块内部各采样孔溴甲烷浓度在20h与箱内浓度基本平衡,15cm处的溴甲烷CT值达到200g.h/m3需13h。 相似文献
3.
熏蒸环境温度为5℃、10℃的条件下,设计6～10个不同剂量分别开展溴甲烷和硫酰氟熏蒸杀灭紫穗槐种子携带紫穗槐豆象(Acanthoscelides pallidipennis)老熟幼虫的毒力试验,应用PoloPlus软件进行机率值分析的结果表明:在5℃条件下,预计紫穗槐豆象老熟幼虫达到99.9968%死亡率所要求的CT值(Lct_(99.9968))为溴甲烷2855.7g.h/m~3、硫酰氟3973.5g.h/m~3,熏蒸24h所需剂量为119.3g/m~3、158.7g/m~3;在10℃条件下,Lct_(99.9968)为溴甲烷2145.2g.h/m~3、硫酰氟1436.3g.h/m~3,熏蒸24h所需剂量为88.1g/m~3、59.0g/m~3。因此,随着熏蒸温度的提高,硫酰氟对紫穗槐豆象老熟幼虫的毒力作用增长明显,可作为进出口紫穗槐种子检疫处理的有效熏蒸剂,但熏蒸的环境温度须高于10℃。 相似文献
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6.
氧硫化碳(COS)作为一种潜在的溴甲烷替代熏蒸剂,日益引起广泛关注。本文以松材线虫为研究对象,首先探讨了氧硫化碳熏蒸松材线虫时,温度和时间因子对其杀灭效果的影响。其次,配制了氧硫化碳和硫酰氟(SO_2F_2)的混剂,分析了不同体积比的混剂对松材线虫的熏杀效果。结果表明,温度和时间是影响氧硫化碳熏杀松材线虫效果的关键因素,熏杀效果随温度和时间的增加而提高;在25℃的条件下,氧硫化碳投药剂量为156.33 g/m~3,熏蒸时间为48 h,确保熏蒸散气前的CT值为3773.79 g·h/m~3时,松材线虫全部死亡;添加10%、30%和50%体积比的硫酰氟对氧硫化碳的熏杀效果增效明显,其中添加50%体积比的硫酰氟后,只需加入89.67 g/m~3的氧硫化碳和70.45 g/m~3的硫酰氟的混剂,即可使松材线虫全部死亡。 相似文献
7.
林木种实害虫熏蒸技术的研究 总被引：1，自引：2，他引：1
本文以国内林木检疫工作中经常遇到的8种林木种子携带的9种检疫性害虫为对象,进行了室内熏蒸试验、室内重复熏蒸试验、产地熏蒸试验。提出了溴甲烷、硫酰氟、氯化苦、磷化铝在-10～0℃、1～10℃、11～20℃条件下,熏蒸处理供试各种检疫性林木种实害虫安全有效 CT 值。测定了紫穗槐、落叶松、柠条、黄连木、刺槐种子在常温条件下对溴甲烷、硫酰氟、磷化铝的吸附量以及这三种熏蒸剂在这5种林木种子内的解吸速度。同时还测定了溴甲烷、硫酰氟、磷化氢、氯化苦在常温条件下,在散装黄连木、落叶松、柠条、紫穗槐、刺槐种子内的渗透力以及氟、氯、溴、磷在食用黄连木种子内的残留量。 相似文献
8.
溴甲烷熏蒸对桃蛀果蛾的毒力作用 总被引：1，自引：0，他引：1
对溴甲烷熏蒸处理桃蛀果蛾结果进行机率值法分析,推算出在25℃温度条件下溴甲烷熏蒸处理1.5h和2h,达到桃蛀果蛾Carposina sasakii Matsumura幼虫死亡率99%的浓度时间乘积(CT值)分别为43.79g·h/m3和46.77 g·h/m3;15℃和10℃温度条件下熏蒸处理3h,达到桃蛀果蛾幼虫死亡率99%的溴甲烷浓度分别为50.84 g·h/m3和118.55 g·h/m3.研究表明,溴甲烷熏蒸对桃蛀果蛾幼虫的毒性作用随着溴甲烷熏蒸浓度的增加而增加,相同熏蒸剂浓度条件下,随着温度升高,溴甲烷熏蒸效果明显增加. 相似文献
9.
国外熏蒸技术及硫酰氟的研究应用状况 总被引：1，自引：0，他引：1
国外广泛地应用熏蒸技术防治各种仑贮农产品及其加工产品,车辆、船仑害虫和房舍白蚁等。硫酰氟是本世纪50年代开发的斯的熏蒸剂,它具有对害虫效力高、不易燃、与室内物品不起化学反应、穿透能力强等优点,被广泛应用于建筑物防治白蚁及各种仑贮物品的熏蒸。 相似文献
10.
进境美国苜蓿草蒸热处理技术初探 总被引：2，自引：0，他引：2
《植物检疫》2019,(3)
为探索蒸热处理应用于进境美国捆包苜蓿草的可行性,本文研究了蒸热处理过程中捆包苜蓿草不同深度内的温度变化,并评估了蒸热处理对苜蓿草外观及主要营养成分的影响。结果表明,从室温29℃开始加热,随着加热时间的延长,热蒸汽从捆包苜蓿草的两端逐渐传递至中心,1 103 min后,捆包苜蓿草内部中心温度可达到56℃;处理后苜蓿草外观颜色变黄,主要营养价值蛋白质含量没有显著变化。 相似文献
11.
溴虫氟苯双酰胺是一种全新的双酰胺类杀虫剂,主要用于防治鳞翅目、鞘翅目、白蚁以及蚊蝇等害虫。为了明确溴虫氟苯双酰胺对小菜蛾的生物活性及解毒酶活性的影响,本研究选择氯虫苯甲酰胺为对照药剂,采用叶片药膜法测定了溴虫氟苯双酰胺对小菜蛾的生物活性,并测定了亚致死剂量(LC20、LC40)的溴虫氟苯双酰胺和氯虫苯甲酰胺对小菜蛾多功能氧化酶、谷胱甘肽S-转移酶和羧酸酯酶活性的影响。结果表明,溴虫氟苯双酰胺与氯虫苯甲酰胺对小菜蛾的生物活性相当,两者对小菜蛾的LC50分别为0.042和0.056μg/mL。与氯虫苯甲酰胺相似,亚致死剂量的溴虫氟苯双酰胺能够诱导小菜蛾体内羧酸酯酶活性升高,但溴虫氟苯双酰胺对多功能氧化酶和谷胱甘肽S-转移酶活性没有显著影响。 相似文献
12.
Toxicity of methyl bromide to soil-borne fungi 总被引：1，自引：0，他引：1
Nineteen fungal isolates, mostly plant pathogens cultured on agar, were subjected to fumigation with methyl bromide at known concentration x time product (CTP, concentration in mg/1 x time in h) in a fumigation chamber at controlled temperature. Survival of the fungi was determined by sub-culturing on fresh agar. An order of methyl bromide tolerance of the fungi was cetermined and it was shown that at low concentrations of the fumigant, prolonged exposure, to give a normally toxic CTP, did not kill important soil-borne pathogens. The implication of this in relation to field fumigations is discussed. 相似文献
13.
通过对红桔油、柠檬叶油、红河橙油、山苍子油、留兰香油、松节油、黄樟油、互叶白千层油、蓝桉叶油9种植物精油,在浓度为40μL/L及熏蒸时间为12、24、36、48、60h下,对长角扁谷盗成虫的熏蒸活性测定,结果表明蓝桉叶油、互叶白千层油、柠檬叶油、留兰香油及红桔油的熏杀效果较好,尤以蓝桉叶油的效果最佳。蓝桉叶油在浓度40μL/L,经12、24、36、48h和60h不同熏蒸时间,对长角扁谷盗的LC50分别为15.29,6.44,6.55,3.32、1.29μL/L;当蓝桉叶油熏蒸浓度为4、8、12μL/L时,其LT50分别为45.48、27.28、17.64h。 相似文献
14.
A method is presented for estimating the persistence and concentration of residual free methyl bromide (MB) present in apples during the aeration period following fumigation. The method is based on determining the rate of decline in concentration of methyl bromide in the exhaust air stream during aeration. The rate was shown to follow two consecutive pseudo-first-order decay curves. The first component of the curve resulted primarily from removal of MB from the free air space in the chamber, and the second component resulted from the desorption of MB from the apples. Estimates of the concentration of MB residue in apples were obtained from the regression parameters for the second decay curve. The technique gave good estimates of the residue concentration over a wide range of fumigation conditions and ventilation rates, and may be useful for determining the duration of aeration period required to achieve a proposed residue tolerance of 0.2 mg kg ?1 methyl bromide. 相似文献
15.
BACKGROUND
Ethanedinitrile (EDN) is a fumigant being commercialized worldwide as an alternative phytosanitary treatment to methyl bromide (MB) for forest products. The penetration characteristics of MB and EDN were measured through the bark of wooden blocks (100 × 100 × 50 mm) cut from the upper (average bark thickness 5 ± 2 mm) and lower (average bark thickness 25 ± 5 mm) trunk of recently felled pine (Pinus radiata D.Don) trees. Doses of 48 g m−3 MB and 50 g m−3 EDN were applied to chambers at 10 and 20°C for 10 h.RESULTS
Penetration of MB was influenced by the interaction between fumigation time and temperature, with concentrations increasing at a higher rate at 20°C compared with at 10°C. After 10 h, an average concentration of 8.05 ± 0.89 g m−3 had penetrated the bark of log sections at 20°C, whereas 5.20 ± 0.89 g m−3 was measured at 10°C. By contrast, the factors examined in this study did not significantly impact the penetration of EDN. Concentration × time (CT) values for MB under the bark were 35.20 ± 2.30 g h m−3 at 10°C and 55.85 ± 9.58 g h m−3 at 20°C; whereas for EDN, CT values were 19.50 ± 6.80 g h m−3 at 10°C and 19.08 ± 4.10 g h m−3 at 20°C.CONCLUSION
MB can achieve a higher concentration under the bark of log sections during simulated fumigations, but all of the factors examined affected the ability of MB to penetrate the bark of wooden blocks. By comparison, the penetration of EDN through the bark is more consistent than MB under laboratory conditions. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献16.
九种植物精油对玉米象成虫的熏蒸作用比较 总被引：14，自引：2，他引：14
采用广口瓶密闭方法,测定红桔油Citrus tangerina、柠檬叶油Citrus limonum、 红河橙油Citrus hongheensis、 山苍子油Litsea cubeba、留兰香油Mentha spicata、松节油Pinus tabulaeformis、黄樟油Cinnamonum camphora、互叶白千层油Melaleuca alternifolia、蓝桉叶油Eucalyptus globulus等9种植物精油,在熏杀浓度为16 μL/L、熏蒸时间为24、36、48及60 h条件下,对玉米象Sitophilus zeamais成虫的熏蒸活性。结果表明:黄樟油、互叶白千层油、柠檬叶油、留兰香油及松节油的熏杀效果较好,尤以黄樟油的效果最佳。黄樟油在12、24、36、48和60 h不同熏蒸时间下的LC50值分别为31.43、11.26、6.16、2.72和1.11 μL/L。可考虑将黄樟油作为磷化氢及溴甲烷的替代药物用于控制玉米象的危害。 相似文献
17.
Kevin N
T Norman 《Pest management science》2000,56(2):154-158
The persistence of methyl bromide (MB) in white rice, brown rice, sultanas, raisins, pumpkin seeds, brazil nuts, groundnuts and walnuts was monitored following laboratory fumigations at different concentration time products and temperatures. A sensitive automated headspace gas chromatographic method with a limit of quantitation of 0.005 mg kg−1 was used to determine MB residues. Nuts and seeds sorbed the highest amounts of MB followed by rice and dried fruit. Measurable MB residues were shown to persist in nuts and seeds for 10 weeks and in dried fruit for four weeks following a fumigation with recommended concentration time products. The data presented suggest MB residues may persist in unprocessed nuts, seeds or dried fruit at the point of consumption using recommended fumigation practices, or particularly following overdosing or multiple fumigations. Crown copyright © 2000 Reproduced with the permission of Her Majesty's Stationery Office 相似文献
18.
温度和土壤水分对祁连山青海云杉林土壤呼吸的影响 总被引：7，自引：2，他引：5
采用美国Li-cor公司生产的LI6400-09土壤呼吸室和LI6400便携式光合作用测量系统对祁连山云杉林土壤呼吸速率进行野外测定,并通过多元回归对其影响因子进行了分析。结果表明:土壤呼吸总体趋势是夏季高,其它季节低,但季节动态呈现不规律的多峰曲线;气温、地表温度以及5cm、10cm、15cm和20cm的土壤温度均与土壤呼吸速率呈显著的指数关系,温度对土壤呼吸的影响在低温时比高温时更显著;土壤呼吸的平均速率为2.145μmol.m-2.s-1。以气温、地表温度以及5cm、10cm、15cm和25cm的土壤温度为依据得到的Q10值依次为2.67、2.23、4.17、4.32、4.36和4.54;0~10cm和10~20cm土层的土壤含水量均与土壤呼吸速率呈相关关系,当土壤水分含量较低的情况下,随着土壤水分含量的增加,土壤呼吸速率也随着增加,但是当土壤水分含量增加到一定程度时,土壤呼吸速率则表现出降低的趋势。 相似文献
19.
为了研究覆膜与氮肥用量对雨养春玉米农田CH_4吸收的影响,在覆膜(FM)与不覆膜(BP)条件下分别设置了0、100、250、400 kg·hm~(-2)4个氮肥水平,共8个处理,采用静态暗箱-气相色谱法对农田CH_4的吸收通量进行连续观测,同时观测影响通量变化的温度、水分以及硝铵态氮等环境因子。结果表明:旱作春玉米农田是甲烷的汇,休闲期的累积吸收量占年总吸收量48%~60%,在年总吸收量中占了不可忽视的一部分;FM0、FM100、FM250、FM400和BP0、BP100、BP250、BP400在2014—2015年的年总吸收量分别为0.99、1.38、1.3、1.37 CH_4-C kg·hm~(-2)和1.43、1.77、1.68、1.56 CH_4-C kg·hm~(-2),地膜覆盖和施氮量的增加均未显著改变雨养春玉米农田对CH_4的吸收量;雨养春玉米农田土壤CH_4的吸收速率与0、10 cm土层土壤温度呈极显著正相关,与土壤孔隙含水量(WFPS)、NH4+-N之间呈极显著负相关,不覆膜条件下与NO3--N之间呈负相关关系,且达到极显著水平(P0.01)。 相似文献
20.
Serial subculturing of an alfalfa field isolate of Verticillium albo-atrum produced two variants which were significantly less virulent than the original. When conidia of the original isolate, stored at − 70 °C, were infused into alfalfa cuttings, the pathogen grew from spore trapping sites into contiguous vessels and began to sporulate within 24 h. The frequency of vessels in which sporulation occurred at 24 h was similar in alfalfa genotypes known to differ in disease ratings and in host resistance to lateral penetration of vessels. With conidia of the two variants as inoculum, hyphae were found to penetrate much more extensively from trapping
ites into adjacent vessels by 24 h. However, the more virulent original isolate sporulated two to three times more frequently. An isolate of V. albo-atrum from potato, which was non-pathogenic to alfalfa, had limited lateral penetrating ability in alfalfa but never sporulated by 24 h in laterally penetrated vessels. Of parameters studied, including sporulation and radial growth, only early vascular sporulation in laterally penetrated vessels correlated with the greater virulence of the original alfalfa isolate. 相似文献