杨木板材干热处理时间预测模型的建立

木质包装热处理标准要求使木材中心温度达到56%并保持30min以上,然而中心温度直接检测受仪器设备、检测技术等因素的影响.为了准确监测中心温度,建立根据环境参数如厚度、含水率、加热温湿度等预测中心温度的数学模型,本项研究使用KBF'/20型恒温恒湿热处理箱,在设定温度为65、70、75、80、85℃,相对湿度分别为50、70、90%的热处理条件下,对厚度为5、7.5、10和12.5cm,含水率分别为20%、50%、75%、100%的杨树木板进行热空气处理试验,对升温速率与各环境参数之间相互关系进行分析,结果表明:升温速率与加热温度、湿度呈直线正相关,与木板厚度、含水率呈直线负相关.在此基础上,利用SPSS进行多元直线回归分析后,建立了预测中心温度达到56℃所需时间的预测模型,其预测值与实测值的偏差的绝对值平均为2.78%,最大偏差为-9.95%和11.73%.     

热处理杀灭木质包装中松材线虫的技术研究

近年来,出入境检验检疫部门多次从经热处理的木质包装中截获松材线虫.本实验利用电热恒温箱和热处理窑对携带松材线虫的进口木质包装进行热处理试验,结果表明:在实验室和工厂化热处理试验中,木材中心温度达到56℃时处理4h不能完全杀灭木质包装中的松材线虫;木材中心温度达到60℃时在实验室试验中需要3.5h方能完全杀灭松材线虫,而在工厂化热处理试验中,木材中心温度达到60℃处理2h,尚不能完全杀灭松材线虫;实验室和工厂化试验表明,仅当木材中心温度达到65℃,保持0.5h以上方能100%杀灭松材线虫.本文探讨了实验结果与目前IPPC推荐的国际标准(即木材中心温度56℃时处理30min以上)不一致的原因.     

针叶类木质包装热浸泡处理试验

为摸索木材热浸泡处理方法,分别用56℃、66℃、76℃的恒温水浴浸泡木段,检测其中心温度,当水浴温度76℃,持续处理时间2h时,直径10cm供试松木中心温度能保持56℃以上30min;水浴52℃条件下,供试松材线虫在5min内被100%杀死.     

含水量和装载量对松木片吸附溴甲烷的影响

在18℃、RH为60%～70%室内恒温条件下,对不同含水率和不同装载量的松木片的熏蒸结果表明:松木片含水量对溴甲烷熏蒸处理效果影响明显。在18℃、8g/m3处理24h,松材线虫死亡率(y)与碎木片含水量(x)之间关系式为:y=129.654-1.062x(R=0.967);碎木片对溴甲烷的吸附随水分含量升高而增加,58%、55%、49%含水率的碎木片对溴甲烷的吸附与含水率为30%、37%碎木片的吸附差异显著。载量对溴甲烷熏蒸处理松木片中松材线虫影响显著,松材线虫死亡率(y)与松木片载量(x)之间关系式为:y=105.809-0.247x(R=0.973);随实验碎木片载量的增加,对溴甲烷的吸附量也加大。     

减压条件下溴甲烷对松材线虫熏蒸效果的研究

利用XMG-35真空熏蒸库在25～30℃和减压条件下,选择不同压力和浓度梯度,模拟对含有松材线虫的木质包装材料进行4h的熏蒸处理.结果表明,回气的条件下,熏蒸压力为30kPa、50kPa、70kPa时,100%杀死木质包装材料中的松材线虫所有虫态的有效剂量分别为72g/m3、80g/m3、88g/m3.减压熏蒸对松材线虫的杀灭效果和环境温度、压力、投药剂量及木质包装材料的厚度有关.     

氧硫化碳及其混剂熏杀松材线虫效果研究

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。     

木质包装松材线虫溴甲烷熏蒸处理

为寻求一定温度下溴甲烷熏蒸处理杀灭木质包装中松材线虫的有效浓度和时间,给国际贸易中木质包装松材线虫的熏蒸处理提供科学依据,进行了木质包装松材线虫溴甲烷熏蒸处理研究.研究分实验室基础试验和集装箱应用试验两部分,先在实验室中筛选出熏蒸有效浓度和时间,再于集装箱中进行应用试验.结果表明:11～15、16～20、≥21℃时,溴甲烷剂量分别为64、56、48g/m3,熏蒸24h,24h时浓度分别不低于32、28、24g/m3,即CT值分别为1152、1008、864 gh/m3,能够100%杀灭木质包装中松材线虫的成虫、幼虫及卵.此外,证实了国际植物检疫措施标准ISPM NO.15<国际贸易中木质包装材料控制准则>中熏蒸处理的要求偏低,不能完全杀灭木质包装中松材线虫.     

国外木质包装热处理除害失效原因分析

本研究设计了热处理除害效果的测定方法；分析了国外热处理失效的主要原因；验证了热处理标准只要木材中心温度不低于56℃，时间不少于30min，就可以达到热处理除害效果。     

外高桥口岸截获松材线虫的情况分析

外高桥局于 1 998年 1 1月 2 7日首次从宁波北仑电厂进口的美国汽轮机木包装箱上截获松材线虫至 2 0 0 0年 1 0月 ,共截获松材线虫 41批 (1 998年 3批 ,1 999年 2 9批 ,2 0 0 0年 9批 ) ,其中从美国进口货物的木包装上截获 3 9批、占 95 % ,从日本进口的木包装上截获 2批、占 5 %。这些松材线虫的截获及除害处理 ,有效地防止了松材线虫的传入及扩散 ,同时为我国政府作出决策 ,要求美国、日本对木包装先行热处理 ,再输入中国提供了有力的依据。本文就外高桥局截获的松材线虫的情况从几个方面统计总结。希望对在检验检疫第一线的工作人员有所…     

落叶松和杨木材料对溴甲烷吸附与尾气交换性能评估研究

室温10～14℃条件下,针对规格为5 cm×10 cm×60 cm、含水率为15%～20%的白杨和落叶松材料,使用不锈钢熏蒸箱(185 L)开展了溴甲烷吸附以及尾气交换试验测试,结果表明:24 h内落叶松的吸附量持续增加,杨木经4 h吸附后基本达到饱和;24 h单位体积(m~3)落叶松、杨木吸附溴甲烷的质量分别为166.0±1.8 g和187.5±1.3 g;在每小时8～9次风量循环熏蒸箱体积的情况下,经过30 min循环,熏蒸尾气中溴甲烷的利用率约为50%,吸附于木质材料中的溴甲烷未发生解吸。基于本试验结果,建议在熏蒸尾气循环应用中增加循环风速,采用间歇循环等措施,提高气体交换效率。     

Assessing risks of pine wood nematode Bursaphelenchus xylophilus transfer between wood packaging by simulating assembled pallets in service

The risks of Bursaphelenchus xylophilus (pine wood nematode) transfer in relation to wood material were assessed. Combinations of infested and non‐infested adjacent boards, long‐blocks and blocks of Pinus pinaster, simulating assembled pallets, were assessed. For the recipient wood, pieces with natural moisture content (MC), heat‐treatment (56°C for 30 min in the core) and kiln‐drying to <20% MC were tested, along with in‐service boards from pallets. Donor and recipient wood materials were kept in direct contact at 25°C or 10°C, with nine replicates per treatment. Bursaphelenchus xylophilus was found to transfer rapidly at 25°C when the wood had an MC above fibre‐saturation point (>30%). Nematode reproduction was rapid and sustained, gradually declining to zero at 40 weeks. Bursaphelenchus xylophilus did not transfer to kiln‐dried or to in‐service wood with an MC below fibre‐saturation point, or to wood at 10°C. The key factors determining nematode transfer were the ambient temperature, the nematode load of the donor wood and the MC of the recipient wood, with a ‘barrier’ of 20% MC below which it becomes unsuitable for nematode transfer. This finding indicates that there is a limited risk of spread of B. xylophilus in treated and untreated solid wood packaging materials.     

Pest survey of softwood boxes,with special emphasis on pinewood nematode,Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae)

Wood packaging material (WPM) is an important pathway for the spread of non‐native plant pests. To reduce the likelihood of plant pest movement with WPM, the International Standard for Phytosanitary Measures No. 15: “Regulation of Wood Packaging Material in International Trade” (ISPM 15) was developed in the framework of the International Plant Protection Convention. To be compliant with this Standard, WPM shipped internationally must be either heat‐treated or fumigated, regardless of any specific characteristics of the WPM. The objective of this survey was to determine if Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae) or insects, especially Monochamus spp. (Coleoptera: Cerambycidae), were present in a specific subset of softwood boxes. While not compliant with ISPM 15, these boxes had been treated with wood preservatives, stored indoors for over five years, and, in addition to meeting various quality standards, almost all had a moisture content below 20 percent. United States Department of Agriculture staff inspected a sample of 630 softwood boxes, focusing on those showing signs of possible pest infestation. Based on a binomial distribution with an efficacy of detection equal to 0.95, a sample size of 630 provides a 95 percent confidence of detecting pests if >0.5 % of boxes are infested. No B. xylophilus or insect pests were found in the boxes, though other nematode genera (Aphelenchoides, Aphelenchus, and Filenchus), which feed on decomposing fungi in wood and do not damage trees, were found in 21 boxes. This study demonstrates that not all types of WPM present a high phytosanitary risk. It may be worthwhile to consider an amendment to ISPM 15 to differentiate between various risk categories of WPM in order to minimize costs and environmental impacts associated with treatments currently prescribed in ISPM 15.     

溴甲烷对松木片中松材线虫的熏蒸作用

采用二次正交旋转组合设计,在室内条件下研究了溴甲烷剂量、熏蒸处理时间和处理温度对松木片中松材线虫熏蒸效果的影响。结果表明,溴甲烷剂量是影响熏蒸效果的最主要因子;14、18 ℃和22 ℃条件下处理24 h,松材线虫死亡率达99.9%时的溴甲烷浓度分别为17.92、16.07、14.87 g/m3; 14、18、22 ℃条件下,松材线虫死亡率达99.9%时,溴甲烷浓度和时间乘积,即CT（99.9）分别为192.52、174.705、166.229 g&#8226;h/m3。溴甲烷可用于口岸松木片中松材线虫的除害处理。     

木质包装中松材线虫的实时荧光PCR检测

松材线虫是进境木质包装中的重要检疫对象之一。本研究以进境木质包装中截获的12种伞滑刃属线虫,包括4种不同来源的松材线虫、3种不同来源的拟松材线虫、豆伞滑刃线虫、大尖尾伞滑刃线虫、阿苏里伞滑刃线虫、伯氏伞滑刃线虫及拟小刺伞滑刃线虫为材料,进行实时荧光PCR检测。结果显示,仅松材线虫可观察到明显的荧光强度变化,而其他线虫的荧光强度没有变化。通过研磨样品的方法,提取单条松材线虫的DNA,进行实时荧光PCR试验,检测成功率为100%,且不论是雄虫、雌虫或幼虫均能检测出来。该研究对于我国口岸进境木质包装中松材线虫的检测具有一定的实际意义。     

嗜菌异小杆线虫的分离鉴定及生物学特性分析

为了发掘具有耐高温特性的昆虫病原线虫,本实验室对在山东地区采集的122份土样进行了线虫分离,得到异小杆线虫JNR,扩增其ITS基因和D2-D3基因,并构建系统进化树,分析可得:线虫JNR与嗜菌异小杆线虫Heterorhabditis bacteriophora在同一分支,同源性达到98%以上,为嗜菌异小杆线虫品系。为进一步了解该线虫品系的生物学特性,本试验研究了其侵染力、高温耐受力及水平运动能力。结果表明,线虫JNR有较好的耐热性,38℃条件下处理16 h,存活率最高54%,24 h时为32%;40℃水浴处理2 h,低浓度500 IJs/mL下存活率28%,3 h后全部死亡。对大蜡螟和小菜蛾的生测结果显示,在10、15、20、25、30、35、40、60、120、240 IJs/头剂量下处理24 h,蔬菜害虫小菜蛾先出现死亡,大蜡螟则在48 h后出现死亡;大于20 IJs/头剂量下,处理48 h后线虫对大蜡螟的校正死亡率达到59.5%,高于对小菜蛾的侵染效果。在剂量120 IJs/头以上,72 h后寄主的校正死亡率均能达到100%。异小杆线虫JNR在30℃条件下水平运动能力比在18、25℃时强,48 h时有31%的个体运动到3.6 cm处。以上研究表明,该线虫有较强的侵染力,特别是在温度相对较高时具有较好的耐热力和水平运动能力,对防治蔬菜田小菜蛾具有应用开发潜力。     

Survival of Bursaphelenchus xylophilus and Monochamus galloprovincialis in pine branches and wood packaging material

Survival and development of Bursaphelenchus xylophilus (pine wood nematode) was studied for up to 40 weeks in Pinus pinaster sawn wood and branches: 30 boards (1200 × 100 × 25 mm), 30 long‐blocks (1200 × 95 × 95 mm), 10 pine branches with bark and nine branches without bark (1200 mm long). The nematode was found in all materials and through the entire sampling period, with higher abundance in the sawn wood (boards and long‐blocks). In the initial period B. xylophilus reproduced abundantly and a population peak was detected at 8–12 weeks. Subsequently, the populations declined and became dominated by third‐stage resistant larvae (J_III), and in the final sample nematode abundance was very low. Nematode decline in the wood was correlated with a decrease in the moisture content (MC) to below fibre saturation. Survival of the insect vector Monochamus galloprovincialis was also assessed in sawn boards (1200 × 100 × 25 mm, n = 31) and blocks (160 × 95 × 95 mm, n = 40). The majority of the larvae were killed when sawing the wood, although some adults successfully emerged from the boards (10% survival) and blocks (37%). These results represent a contribution to the quantification of the risks of dispersing pine wilt disease through wood packaging materials, confirming that untreated wood can support healthy and abundant B. xylophilus populations for sufficient time for vectors surviving the sawing process to complete their development, to emerge and disperse the nematode.     

Seeking alternatives to probit 9 when developing treatments for wood packaging materials under ISPM No. 15

ISPM No. 15 presents guidelines for treating wood packaging material used in international trade. There are currently two approved phytosanitary treatments: heat treatment and methyl bromide fumigation. New treatments are under development, and are needed given that methyl bromide is being phased out. Probit 9 efficacy (100% mortality of at least 93 613 test organisms) has been suggested as an evaluation criterion for new wood treatments, and is based on fruit fly research. We question requiring probit 9 efficacy for wood pests (insects, nematodes and fungi) and discuss challenges to meeting this requirement. Instead, we suggest a 3‐step, laboratory‐based alternative approach. Step 1 involves laboratory experiments (screening) to estimate the lethal dose for the most tolerant stage of each target pest. We consider each infested piece of wood as an experimental unit, not the individual pests, to avoid pseudoreplication. Step 2 requires replicated experiments (with no survivors) at the estimated lethal dose. We suggest a minimum sample size of 60 experimental units, which achieves 0.95 statistical reliability at the 95% confidence level. Step 3 entails studies under simulated operational conditions using wood samples similar in size to wood packaging material and infested to levels that reflect field conditions.     

桃小食心虫病原菌—球孢白僵菌TST05菌株生物学特性研究

[目的]研究从自然染病的桃小食心虫幼虫上分离的球孢白僵菌TST05菌株的生物学特性.[方法]测定不同培养基、外界不同温度和湿度对该菌株菌丝营养生长及孢子萌发的影响.[结果]该菌株在PDA、PPDA、SDAY、SMAY 4种培养基上均生长良好,菌落厚而致密,产孢量均大于3.95×107孢子/mL;菌株适应的温度和湿度范围宽,15～30℃之间,RH 30 ％～100％之间孢子均可萌发、生长和产孢.随着温度接近25℃、湿度增大,孢子的萌发率、菌落的生长速率和产孢量都显著增加.15℃、RH 100％时产孢量为1.32× 107孢子/mL;25℃、RH 30％时,产孢量也能达到1.37×107孢子/mL;25℃、RH 100％时产孢量达到6.19×107孢子/mL.15℃、RH 100％孢子萌发率为52.28％;25℃、RH＞80％时,孢子萌发率都能达到90％以上.[结论]TST05菌株能适应北方干旱低温条件,可开发成为防治桃小食心虫的生物制剂.     

Suppression of pine wilt disease by an antibacterial agent,oxolinic acid

BACKGROUND: Pine wilt disease (PWD) is very complex and has been reported to be caused by pine wood nematode, Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle, and its accompanying bacteria. However, there is no report on the control of PWD by antibacterial agent. The present study was performed to investigate disease control efficacy of antibacterial agents against PWD. RESULTS: Among six antibacterial antibiotics tested, oxolinic acid (OA) showed the strongest antibacterial activity against five bacteria isolated from three strains of pine wood nematode. In in vivo assay, it effectively suppressed the development of PWD in three‐year‐old seedlings of Pinus densiflora Sieb. & Zucc.; it showed 71% control when injected at 3 mg per seedling. A mixture of OA and the nematicidal agent abamectin (Ab) showed higher disease control efficacy against PWD than either OA or Ab alone. In addition, OA alone and a mixture of OA and Ab also controlled PWD in approximately 20‐year‐old pine trees under field conditions. CONCLUSION: This is the first report on the suppression of PWD by OA. The result strongly indicates that PWD could be controlled by antibacterial antibiotic alone and a combination of antibacterial and nematicidal agents. Copyright © 2010 Society of Chemical Industry     

进境木包装松材线虫检验检疫制样方法比较

对来自日本、韩国的进境木包装 ,采用不同直径的电钻钻取木屑各 1 0 g和采用薄木片 1 0 g ,进行 6次重复制样进行线虫分离 ,结果表明差异显著。同时采用薄木片 1 0 g、30 g、6 0 g进行线虫分离 ,同样差异显著。进境木包装用电钻取样 ,获得线虫量较小 ,不能在实际工作中运用。薄木片制样 ,能较多的获得线虫 ,符合进境木包装检疫工作的需要。