【作者】 袁菲；

【导师】 骆有庆；

【作者基本信息】 北京林业大学 ， 森林保护， 2010， 博士

【摘要】 阿尔山林区历史上曾在1982年、1992年和2002年三次暴发落叶松毛虫Dendrolimus superans Bulter的危害,第三次暴发后大量次期性害虫(落叶松八齿小蠹Ips subelongatus Motschulsky、云杉大黑天牛Monochamus urussovi Fisher、云杉小黑天牛Monochamus sutor Linnaeus、白带长角天牛Acanthocinus carinulatus Gebler等)快速侵入。本文以内蒙古阿尔山林区的落叶松林Larix gmelinii (Rupr.)Rupr.为研究对象,分析了落叶松毛虫与蛀干害虫这两类害虫之间的发生规律和侵入顺序；对次期性蛀干害虫在落叶松上的功能生态位进行研究,明确各钻蛀性害虫对其危害的不同程度,找出相应的生态对策控制虫害的暴发和蔓延；对优势蛀干害虫国内新记录种白带长角天牛的生物学特性进行了研究；同时运用聚集信息素监测与防治优势蛀干害虫落叶松八齿小蠹,对其天敌的种类与控制作用进行调查。主要研究结果如下：1.通过设置标准样地、笼内收集和虫害木解析等方法,对阿尔山林区主要钻蛀性害虫的跟进顺序、生态位、对寄主的影响程度等进行了研究,结果表明：阿尔山林区落叶松毛虫危害后造成树势衰弱,落叶松八齿小蠹首先入侵,然后是白带长角天牛,最后是云杉大黑天牛和云杉小黑天牛。落叶松毛虫暴发后三种天牛的平均虫口密度随之上升。落叶松八齿小蠹在落叶松主干上占据的生态位从树干基部到接近树顶部,在老龄立木上的虫口数量大于中龄立木,不危害健康树；白带长角天牛在枯死木中占据的生态位较衰弱木上高,危害程度与树龄、树皮厚度呈正比；云杉大黑天牛在衰弱木上主要危害4m以下树干,枯死木上可危害至6m；云杉小黑天牛在衰弱木上主要危害5m以下树干,枯死木上可危害至7m,危害程度与树龄呈正比,三种天牛均不危害健康树和幼树。主要钻蛀性害虫中,落叶松八齿小蠹的危害程度远远大于三种天牛。2.在落叶松衰弱立木上,生态位宽度以落叶松八齿小蠹最高,在中龄和老龄树上分别达到0.5782、0.5498,在落叶松中龄和老龄枯死立木上,白带长角天牛的空间生态位宽度分别达到0.5143、0.6294,分布较衰弱木广,而云杉大黑天牛空间生态位宽度在衰弱和枯死立木上都最低。在落叶松立木上的空间生态位重叠指数以落叶松八齿小蠹对其他三种优势天牛偏高,天牛之间的空间生态位相似性比例指数均较高且差距较小,说明四种害虫对空间生态位的占据有很大相似程度。四种害虫的空间种间竞争系数均很大,说明对空间和资源的竞争非常激烈,在这种情况下四种害虫能够共存,根本原因是由于取食部位的分化。3.应用多个聚集度指标和Iwao, Taylor等的回归分析法对落叶松八齿小蠹坑道在落叶松主干上的垂直分布进行了研究。落叶松八齿小蠹坑道数量与落叶松树干不同高度变化成线性关系,拟合的直线方程为y=-10.867x+92.884(R2=0.9995)；坑道的分布与落叶松立木阴面和阳面关系不大；当落叶松八齿小蠹的平均虫口密度达到1120头/1000cm2时,落叶松八齿小蠹的坑道基本属于均匀分布。4.白带长角天牛在中国东北内蒙古阿尔山林区一年一代,在落叶松树上只危害韧皮部,以幼虫在韧皮部虫道内越冬,老熟后于次年5月化蛹,5月下旬为化蛹高峰期,蛹期45天左右。6月初羽化成虫,成虫羽化后补充营养,6月底至8月上旬为成虫交配产卵期,成虫一生可多次交尾。卵产于树缝内,其中70.5%的树缝内一粒卵,6.8%的树缝内三粒卵,22.7%的树缝内无卵。卵期7-11天。7月上旬新一代幼虫孵化,孵化率37.8%。9月初幼虫越冬。5.应用落叶松八齿小蠹聚集信息素对内蒙古阿尔山林区落叶松八齿小蠹的月扬飞规律、日扬飞规律、林缘外不同距离以及林内不同高度诱捕器诱集效果等进行了试验,结果表明：落叶松八齿小蠹的成虫发生期从5月中旬开始,到8月底结束,期间有两次明显的扬飞高峰期；成虫主要集中在中午12点、下午2点和4点天气最热的时候活动；林缘外此聚集信息素对落叶松八齿小蠹的有效引诱距离为200米左右,在90米以内引诱效果最佳；林内树干1.5m处为最佳的诱捕器设置高度。6.用购自两个公司的两种不同落叶松八齿小蠹引诱剂(引诱剂1,引诱剂2)分别对落叶松八齿小蠹及其天敌红胸郭公虫Thanasimus substriatus Gebler进行室内GC-MS分析、触角电位试验以及室外的田间引诱试验,结果表明：落叶松八齿小蠹和红胸郭公虫对两种引诱剂反应完全不同,落叶松八齿小蠹对化合物引诱剂2 (ipsenol占主要成分)反应强烈,且引诱剂2诱集的落叶松八齿小蠹数量远远大于红胸郭公虫,说明ipsenol占主要成分同时结合少量的2-methyl-3-buten-2-ol以及一些植物源挥发物可以诱集到大量的目标害虫落叶松八齿小蠹,同时对捕食性天敌红胸郭公虫也有引诱作用；红胸郭公虫对化合物引诱剂1 ((S)-cis-verbenol占主要成分)反应强烈,说明在化合物组分中(S)-cis-verbenol占主要成分,同时结合少量的ipsenol,1-verbenone以及一些植物源挥发物可以诱集到大量的捕食性天敌,但是对目标害虫落叶松八齿小蠹几乎没有作用。Ipsenol对诱集落叶松八齿小蠹起重要作用,而(S)-cis-verbenol则对诱集天敌红胸郭公虫起重要作用,试验结果为以后的害虫监测以及生物防治提供了理论依据。7.对内蒙古阿尔山地区落叶松八齿小蠹天敌的调查,发现落叶松八齿小蠹天敌包括捕食性天敌红胸郭公虫,寄生性天敌暗绿截尾金小蜂Tomicobia seitneri (Ruschka)、长蠹刻鞭茧蜂Coeloides bostrichorum Giraud以及螨类、微生物。分析了天敌的自然控制作用,红胸郭公虫对落叶松八齿小蠹成虫的日最大捕食量为10.7头(1头红胸郭公虫成虫与20头、40头、60头、80头、100头落叶松八齿小蠹成虫,室内17-25℃)；暗绿截尾金小蜂对落叶松八齿小蠹幼虫的寄生率为20.5%,对其蛹的寄生率为13.7%；长蠹刻鞭茧蜂对其幼虫的寄生率为6.5%；而微生物对落叶松八齿小蠹幼虫的寄生率为4.3%,对蛹的寄生率为5.4%,对成虫的寄生率为2.1%。暗绿截尾金小蜂是落叶松八齿小蠹最有利用价值的天敌昆虫。更多还原

【Abstract】 There had been three outbreaks of Dendrolimus superans Bulter in Aershan of Inner Mongolia. After the third outbreak, many insect borers such as Ips subelongatus Motschulsky, Monochamus urussovi Fisher, Monochamus sutor Linnaeus and Acanthocinus carinulatus Gebler invaded Larix gmelinii (Rupr.)Rupr. forests quickly. In this paper, based on the research objectives of L. gmelinii forests, the rule between these two kinds of pests and invasive sequence was analyzed; the function niche in the larch of secondary pests was studied, as for definituding the different damaged extend of insect borers and finding the relative ecological measures to control the outbreak and spreading of pests; biological characteristics of A. carinulatus was studied with detail; meanwhile as for monitoring and controlling I. Subelongatus, aggregation pheromone was used and natural enemies and their suppressive effects were also discussed and analyzed. The main results are as follows:1. Methods involved included setting sample plots, collecting adults in iron traps and measuring areas of galleries to study the invasive sequence, their ecological niche and the extent of the different effects by the main insect borers to their hosts. The results showed that the damage of D. superans weakened L. gmelinii, First I. subelongatus invaded, followed by A. carinulatus, M. urussovi and M. sutor. After the outbreak of D. superans, the average density of longhorn beetles per L. gmelinii tree increased. The ecological niche of I. subelongatus stretches almost from the base to the top of the trunk. The number of insects in older stands of L. gmelinii is larger than those in middle aged stands. They do not damage healthy trees of L. gmelinii. The ecological niche of A. carinulatus is higher in dead L. gmelinii trees than in weak ones. The degree of damage is directly proportional with age and depth of bark. M. urussovi mainly damages trunks below 4 m in weak trees; in dead trees they can do damage up to 6 m in height. M. sutor mainly damages trunks below 5 m in weak L. gmelinii trees; in dead trees they cause damage up to 7 m. Again, the degree of damage is directly proportional with age. None of the three species of longhorn beetles damage healthy L. gmelinii and younger trees. Among the main insect borers, the degree of damage caused by I. subelongatus is more serious than that of other insects.2. Studies on the ecological niche of the main insect borers in larch were carried out, main attention was paid to M. urussovi, M. sutor, A. carinulatus and I. subelongatus. The results showed that the spatial niche breadth index of I. subelongatus was the highest in weak standing larch, in middle aged and old larches it reached the values of 0.5782 and 0.5498, respectively. In the middle aged and old dead standing larches the spatial niche breadth index of A. carinulatus was 0.5143 and 0.6294, respectively, which is higher than in weak larches. The spatial niche breadth index of M. urussovi were the lowest in both weak and dead larch. Both the spatial niche overlap index and spatial niche proportion index of I. subelongatus to the three longhorned beetles were high, which indicated that the demand for space resources of the four insect species had little difference. The spatial interspecific competition coefficient of the four species was high, which indicated that the competition of space and resources was strong. Because of the different damaged areas in the trunk the four species can coexist. 3. Spatial distribution pattern of I. subelongatus galleries was examined by several aggregation indexes and regression analysis methods of Iwao, Taylor. The results indicated that the number of I. subelongatus galleries has linear relationship to the different height of larch trunk, linear regression equation is y=-10.867x+92.884 (R2=0.9995); galleries of I. subelongatus in sunny sides and shaded sides are nearly the same; when the average density of I. subelongatus reached 1120/1000cm2, galleries of I. subelongatus was uniform distribution.4. Biological characteristics of a new record pest insect A. carinulatus has been reported in China for the first time. During the last few years, outbreaks of this insect in larch plantations of the Aershan, Inner Mongolia have occurred. Each year one generation is born. The insects only damage the phloem in L. gmelinii, overwinter in galleries as larvae and pupate in May of the following year. The pupation culminates in late May. The pupal phase lasts about 45 d. Adults emerge in early June and require nutrition after emergence. Mating and oviposition occur from late June to early August and the adult males and females and may copulate many times in their lifetime. The female adults lay eggs in bark crevices. Oviposition sites with one egg occupy 70.5%,of all sites, sites with three eggs 6.8% and 22.7% of all crevices are without eggs. Eggs stay in this stage for a period of 7 to 11 d. Larvae hatch in early July and hibernate in early September. The rate of successful hatching is only 37.8%.5. Emergence regularity of I. subelongatus and attractive effect at different distance outside the forest and different hanging height in the forest were studied with aggregation pheromone of I. subelongatus in Aershan area, Inner Mongolia. The results showed the adult emerged from mid May to the end of August with two peaks. Its active time was between 12:00 and 16:00 when the temperature was relative high in a day. The effective attractive distance of I. subelongatus pheromone was about 200 m and the optimum distance was within 90 m. The best hanging height of the traps was about 1.5 m on trunk.6. Two different I. subelongatus lures (Ipslurel, Ipslure2) from two different manufacturers were tested on I. subelongatus and Thanasimus substriatus Gebler by using Gas Chromatography-Mass Spectrometry (GC-MS), electroantennogram (EAG) and field trapping. The results showed that I. subelongtus and its predator T. substriatus responded in significantly different ways to pheromone blends. Ipsenol-dominant blend attracted a high number of I. subelongatus and some T. substriatus, ipsenol with few 2-methyl-3-buten-2-ol and plant volatiles was attractive to I. subelongatus and T. substriatus as well; (S)-cis-verbenol-dominant blend attracted a high number of T. substriatus but almost no I. subelongtus. (S)-cis-verbenol with few ipsenol,1-verbenone and plant volatiles was attractive to predators but no bark beetles. These present results can be applied for population monitoring and biological control of Ips subelongatus.7. The natural enemies of I. subelongatuswere investigated. The most abundant species were the predatory beetle T.substriatus and the parasitic wasps Tomicobia seitneri (Ruschka) and Coeloides bostrichorum Giraud. In addition, some yet unidentified parasitic mites and pathogenic organisms were also recorded. The natural suppressive effects of the predators and parasitoids were analysed. The maximum predation of T.substriatus was 10.7 Ips beetles per day (1 T. substriatus with 20,40,60,80,100 I. subelongatus,17-25℃indoors). The parasitic rates of T. seitneri to I. subelongatus larvae and pupae were 20.5% and 13.7%, respectively. The parasitic rate of C. bostrichorum to I. subelongatus larvae was 6.5%. The parasitic rate of pathogenic organisms to I. subelongatus was 4.3%(larvae),5.4%(pupae) and 2.1%(adults). Our results indicate that T. seitneri is probably the most potential candidate for biological control of I. subelongatus.更多还原