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1.
The population density and distribution of the three major boring pests,Holcocerus artemisiae,Sphenoptera sp.and Adosopius sp.were studied in their host plant Artemisia ordosica.Results show that the larvae of H.artemisiae mainly bore the rhizome of A.ordosica,but also the larvae of Sphenoptera sp.and Adosopius sp.bore the rhizome of A.ordosica.The adults of Sphenoptera sp.and Adosopius sp.feed on the leaves of A.ordosica as a nutritional supplement.The distribution of the larvae of three pests in their hos...  相似文献   

2.
[目的]松材线虫病是我国对森林危害和威胁最严重的病害,控制其传播媒介昆虫松褐天牛是防治松材线虫病的主要手段。作者发现的松褐天牛深沟茧蜂(Iphiaulax monochamusi Yang)是寄生松褐天牛中老龄幼虫的重要天敌。为明确松褐天牛深沟茧蜂的寄生率与寄主树木、寄主和环境因子的关系,开展了本研究。[方法]通过解剖46株松褐天牛危害致死的马尾松,调查了松褐天牛深沟茧蜂寄生率与马尾松、松褐天牛和环境因子之间的关系。[结果]调查研究表明:寄主树木的高度、胸径和树龄对松褐天牛深沟茧蜂寄生率没有显著影响,松褐天牛的数量对松褐天牛深沟茧蜂寄生率亦没有显著影响,而松褐天牛幼虫龄期和松褐天牛幼虫在树干上的位置显著影响松褐天牛深沟茧蜂寄生率。松褐天牛深沟茧蜂寄生率与松褐天牛龄期呈显著正相关,其偏好寄生3~5龄幼虫;就天牛在其危害寄主树木上的位置而言,松褐天牛深沟茧蜂偏好寄生马尾松主干上部和在韧皮部危害的松褐天牛幼虫,其对位于马尾松树干上部的寄主幼虫寄生率最高,达27.38%,对在韧皮部生活、危害的寄主幼虫寄生率为20.18%,显著高于位于木质部生活的寄主幼虫寄生率(5.46%)。逐步回归分析表明:影响松褐天牛深沟茧蜂寄生率的关键环境因子是寄主树木的坡位和其它天敌寄生率,其中,坡位与松褐天牛深沟茧蜂呈显著正相关,其它天敌寄生率与松褐天牛深沟茧蜂寄生率呈显著负相关。[结论]以上研究初步明确了松褐天牛深沟茧蜂的寄生率与寄主树木、寄主害虫和天敌之间的关系,为今后利用该重要天敌控制松褐天牛打下了基础。  相似文献   

3.
Of all plant materials used to cover the roofs of traditional Japanese buildings, Japanese cypress (Chamaecyparis obtusa) bark, hiwada, has the longest service life and has been used from ancient times. However, wood and bark properties after hiwada harvest have not been evaluated in detail. We studied whether decortication for hiwada production in winter affected xylem and phloem formation. Decorticated trees still preserved all inner bark and part of the outer bark, and both decorticated and control trees had similar annual ring structures at all stem heights in the xylem and phloem. In both xylem and inner bark, no significant difference in ring width at any stem height was found between annual rings before and after decortication. Thus, this study revealed that the decortication of bark for hiwada production does not affect the formation of xylem and the inner and outer bark if decortication is carried out by highly skilled workers in winter.  相似文献   

4.
A trial to detect optimal pin-pricking timing in evaluating the ability to form traumatic resin canals (TRCs) of Cryptomeria japonica was examined to select resistant trees to Semanotus japonicus using 14 clones in 2001 and 2002. Resistance to S. japonicus and the ability to form TRCs in the phloem was evaluated by inoculating newly hatched larvae in the bark and by a pin prick, which was conducted every 10 days (four times) on the trunk around the larval phloem-feeding period, respectively. The larval survivorship varied greatly among clones for both years. The mean appearance of newly formed TRCs was generally higher in late treatment for both years, and the tangential width of them was also higher in 2001, whereas those of pre-formed TRCs were not higher for either year. The larval survivorship did not show significant correlations with the appearance and the width of pre-formed TRCs on all treatments. However, it showed significant negative correlations with the appearance of newly formed TRCs on the second and third treatments on the 2-year-old layer, although this was not significant with the width of them. This suggests that resistant clones might have the mechanism of rapidly forming TRCs when just at the stage of newly hatched larval entering the phloem. Thus, although the relationship between the appearance and the width of newly formed TRCs is not clear, pin-pricking treatment when the newly hatched larvae just enter the bark may be one of optimal times for the evaluation of the resistance of C. japonica to S. japonicus. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

5.
In Honghuaerji region,Scambus sp. is an effective natural enemy of the mongolian scotch pine cone weevil (Pissodes validiirostriis Gyll). The percentage of parasitism on larvae of the mongolian scotch pine cone weevil amounts to 20 to 30% commonly, sometimes as high as 45% or more, thus significantly regulating the weevil population. But the high mortality of larvae ofScambus in winter, which according to the surveys (conducted in 1986, 1987, and 1988) were 24.00%, 51.03% and 47.70% respectively, seriously influenced the natural suppression effect. In order to reveal the cause of winter death of this natural enemy, from 1990 authors studied the winter physiological indices, cold hardiness and overwintering protection ofScambus larvae, in the purpose of providing scientific basis of usingScambus in biological control.  相似文献   

6.
The artemisia weevil, Adosomus sp., has become an important wormwood (Artemisia ordosoca and A. sphaerocephala) pest in recent years in Ningxia Province, China. The number of larval instars should be determined before further studies on its life history, biology and integrate management of pest (IMP). In this study, we measured the length and width of head capsule, based on frequency histograms and Dyar’s law, from which we concluded that the larvae of Adosomus sp. have four instars. Of the two variables measured, the width of head capsule provided the best division of instars. The average width of head capsule of the 1st instar larvae was 1.348±0.152 mm, the 2nd 2.109±0.199 mm, the 3rd 3.563±0.492 mm and the 4th 5.974±0.581 mm.  相似文献   

7.
[目的]日本学者Kosaka与Ogura发现松褐天牛成虫除携带松材线虫外,雌成虫卵巢内还携带有另一种线虫,他们将其命名为卵巢线虫,并认为这种线虫是松褐天牛成虫的寄生性线虫。我国对该种线虫的研究迄今未见报道。为了证明这种线虫在我国是否存在和分布,开展了本项研究。[方法]分期分批捕获刚羽化的松褐天牛雌雄成虫,采用解剖松褐天牛成虫松树木质部及感病的松褐天牛幼虫等方法,调查卵巢线虫的存在与分布。[结果]通过调查研究,发现我国的松褐天牛成虫体内有该卵巢线虫存在,分布于松褐天牛成虫、幼虫体内和松树木质部3个部位;在松褐天牛成虫体内的卵巢线虫通过松褐天牛雌成虫产卵而接种、进入寄主树木木质部中。同时,木质部的卵巢线虫也有一部分进入松褐天牛幼虫体内寄生,另一部分仍在木质部生活,当松褐天牛幼虫再次发育为成虫时,在木质部中的卵巢线虫和已被寄生的松褐天牛幼虫体内的卵巢线虫再次进入松褐天牛成虫体内,完成循环。卵巢线虫在松褐天牛雌、雄虫体内均有分布,携带率为44.4%,其中松褐天牛雌成虫携带率为43.8%,松褐天牛雄成虫携带率为45.0%,两者间无显著差异;每头松褐天牛成虫平均携带卵巢线虫574条,其中雌成虫平均携带816条,雄成虫平均携带308条,具显著差异。初步研究表明,卵巢线虫在松褐天牛成虫体内只能完成产卵到1~4龄的幼虫阶段,不能完成一个完整的世代;在松褐天牛幼虫体内寄生和在木质部生活的卵巢线虫能完成一个完整世代,但具体过程尚不清楚;调查中未观察到卵巢线虫对松褐天牛成虫有寄生致病或致死的现象,但对松褐天牛幼虫有寄生致死的能力;卵巢线虫常与松材线虫同时存在,而且侵入松树及离开松树的方式与松材线虫相同。[结论]我国松褐天牛体内也发现有卵巢线虫存在;目前尚不能证明该线虫对松褐天牛成虫具有寄生致死性,但对松褐天牛幼虫具有一定的寄生致死性;卵巢线虫的生活史与松材线虫相似,是否与松材线虫一样对松树具有危害性以及其病理作用还有待于进一步研究。  相似文献   

8.
沙蒿尖翅吉丁幼虫危害特性和空间格局研究   总被引:2,自引:0,他引:2       下载免费PDF全文
油蒿(Artemisia ordosica Krasch.)为菊科蒿属半灌木,具有耐旱、耐瘠薄、抗风蚀、喜沙埋、结实丰富、采种容易、生长迅速、固沙作用强等特点,是我国重要的荒漠灌木林植物,在荒漠化防治中具有特殊的重要作用。近年来,由于生态环境的改变,灾害性天气频发,我国内蒙古、宁夏、陕西等地的油蒿灌丛内  相似文献   

9.
Pittosporum tobira L. (Family Pittosporaceae) is an important plant species grown in parks and gardens in Turkey. The cottony cushion scale, Icerya purchasi Maskell (Homoptera: Coccina, Margarodidae), is an important pest of P. tobira, and causes damage mainly to the leaves, branches and stems of the host plant. In spite of the great economic importance of I. purchasi to its host plant P. tobira, information has been limited on some basic anatomical parameters of the nature of the damage to leaves and branches. The present study was, therefore, initiated to investigate the insertion and penetration of stylets into the leaves and branches of P. tobira, the length of stylets and depth of penetration in both of these tissues, and penetration of stylets into the cortex, xylem and phloem tissues and into the secretory and non-secretory canals of the leaves and branches. The results showed great variations between the leaves and branches in all the criteria observed in I. purchasi infesting P. tobira. The study found 20 whole and 23 broken mouthparts in the leaves as compared to 3 whole mouthparts and 1 broken in the branches. Length of the stylets inserted into the leaves ranged from 33.83 m to 540.93 m and into the branches from 202.85 m to 340.8 m. The stylets reached greater depths in the leaves, at 540.93 m, as compared to 498.67 m in the branches. The stylets in the leaves were associated with 12 secretory canals, but with none in the branches. It was found that three stylets reached xylem in the leaves as compared to one in the branches. Similarly, 17 stylets in the leaves reached to the phloem, but only 2 in the branches. No stylets were found in the cortex of the leaves, but one was found in the branches. In the leaves, 11 stylets reached and remained in the non-secretory canals, but none in the case of the branches.  相似文献   

10.
The factors involved in the successful escape of overwintered larvae of Epinotia granitalis from host oleoresin in the phloem of Cryptomeria japonica were studied. The mortality, period, and body weight of E. granitalis overwintered larvae while feeding on the phloem of C. japonica were compared with the same parameters for Semanotus japonicus larvae. The seasonal fluctuation in the ability of C. japonica to form traumatic resin canals in the phloem was also assessed. The oleoresin mortality of E. granitalis was low compared with that of S. japonicus. Although both species started feeding on approximately the same date in spring, the feeding period of E. granitalis was only about 24 days, showing that E. granitalis faced the danger of host oleoresin for a shorter period than S. japonicus. The larval weight of E. granitalis was consistently greater than that of S. japonicus through the phloem-feeding period of E. granitalis, and the growth rate was also higher in E. granitalis, suggesting that E. granitalis had a better ability to avoid host oleoresin. These results demonstrated that not only the feeding habits, that is, the tendency of a single larva to feed at several sites, but also the shorter feeding period and larger body size were probably the important factors facilitating escape of E. granitalis from host oleoresin mortality. Furthermore, the ability of C. japonica to form traumatic resin canals increased after the starting date of larval feeding in spring. Because E. granitalis finished feeding before the culmination of the ability of C. japonica to form traumatic resin canals, it was likely that the shorter feeding period was the most important factor in enabling E. granitalis to escape from mortality by host oleoresin.  相似文献   

11.
Sugar beet, Beta vulgaris L. is a strategic crop of sugar industry in Egypt. It is threatened by several insect pests among most important of them is the beet beetle Cassida vittata. This work deals with the biological control of this insect using four Egyptian and imported entomopathogenic nematodes (EPNs). The nematodes included Steinernema carpocapsae S2, Heterorhabditis bacteriophora S1, S. feltiae and H. bacteriophora (1-3). Daily mortality of larvae, pupae and adults of C. vittata were recorded after treatment with serial concentrations (from 500 to 4,000 infective juveniles/ml) of each of four studied EPNs. Development of nematodes in insect bodies was followed up. S. carpocapsae S2 was chosen for the application against different stages of the pest in a sugar beet field. In the field, single application of S. carpocapsae S2 killed 65% of the larvae, 92% of the pupae and 57.3% of the adults of C. vittata within a week. This work is the first report on using the EPNs to control sugar beet beetle.  相似文献   

12.
利用蒲螨和管氏肿腿蜂防治双条杉天牛幼虫   总被引:5,自引:0,他引:5       下载免费PDF全文
Pyemotes sp. and Scleroderma guani were used to control the larvae of Semanotus bifasciatus. The results as follows: (1) the suitable control time of Pyemotes sp.was from early April to early May. The reason was that in this time, the larvae of S. bifasciatus were young and not bored into xylem that was so easy to be parasitized by Pyemotes sp. With the parasitic rate 80% in average. Indoor experiment showed that the Pyemotes sp. had the same tropism selection to every instar for the host, but the parasitic rate was higher in low instar than other instars.(2)Using Scleroderma guani to control S. bjfasciatus, the suitable time was from mid May to mid June, the optimal ratio of host and parasite was 1∶ 1. Indoor experiment showed that Scleroderma guani had strong tropism toward middle-aged and elder larvae, the parasite linger around them and choose suitable position on hosts where they could lay eggs successfully. This behavior showed that Scleroderma guani had strict selectivity for their hosts. In experiment, the authors found a phenomenon that in one trap wood, both the Pyemotes sp. and Scleroderma guani could be found at the same time, they themselves did not affect each other and otherwise they could increase the parasitic rate for host. So, the authors suggested that in practice to control pests especially for boring pests, the Scleroderma guani and Pyemotes sp could be used at the same time.  相似文献   

13.
铁杉大痣小蜂(Megastigmus sp.)隶属膜翅目Hymenoptera细腰亚目Apocrita长尾小蜂科Torymidae大痣小蜂属Megastigmus,在云南省主要分布于丽江市、维西县。通过野外调查和标本采集,并结合室内饲养观察,对其生物学特性进行了研究。结果表明该虫在丽江1年发生1代,完全在种子内取食、发育。  相似文献   

14.
松墨天牛生物学特性的研究   总被引:18,自引:0,他引:18  
松墨天牛在福建闽北1a发生1代,以3~5龄幼虫在蛀道内越冬,极少数以低龄幼虫在树皮下越冬。4月上旬越冬幼虫在木质部内做一椭圆形蛹室化蛹,历时13~15d后成虫羽化。羽化后的成虫从蛹室向外咬圆形的羽化孔道飞出,6月上中旬是成虫羽化出孔的高峰期。成虫的雌雄性比为1∶1。在林间,成虫寻找松树嫩枝树皮补充营养,5~9d后开始交尾产卵,产卵前在树皮上咬刻槽,造成泪滴状松脂流下,1刻槽产卵1粒,少数可产2~4粒。卵期6~10d。幼虫孵化后取食松树内皮和韧皮部,在树皮外可见白色纤维状或褐色粉末状木屑与粪便的混合物。3龄幼虫咬一长椭圆形蛀入孔进入木质部,此后树皮外不再出现蛀屑。幼虫在蛀入木质部前死亡率极高,只有31 68%能蛀入树干中,幼虫期易受白僵菌侵染。幼虫期260~310d。  相似文献   

15.
The biology and host plant range of Lixus nordmanni Hochhuth were studied in the eastern part of Turkey. This weevil feeds and grows on Heracleum trachyloma Fisch. et C.A. Mey, Heracleum sosnowskyi Manden, Heracleum pastinacifolium C. Koch, H. platytaenium Boiss., Angelica sylvestris L. and Falcaria sp. of the family Apiaceae (=Umbellifera). In the early spring, adults emerged from overwintering places and started feeding on host plants. After feeding for several days on leaves, they mated and laid eggs on the main stem of a host. After emergence, larvae fed in stems up to late summer and pupated in the same places. Pupae were found at the beginning of autumn and then adults of the new generation emerged from the stem. Most of adults overwinter under dry plants at rootneck and under stones. L. nordmanni have one generation per year in eastern Anatolia. This Caucasian weevil species is recorded for the first time for Turkish fauna. The biology and host plant records are presented.  相似文献   

16.
[目的]本研究有助于了解EXP基因家族的基本特征,为深入研究其功能搭建平台。[方法]本研究对从巨桉(Eucalyptus grandis Hill)中筛选出35个EXP基因家族成员(Egr EXP1 Egr EXP35),利用生物信息学方法对其基因特征与表达模式进行综合分析。[结果]巨桉EXP基因分布在8条染色体之上,EXP蛋白均定位在细胞质膜上发挥作用,大多数的家族成员具有信号肽。巨桉EXP编码的蛋白质由α-螺旋、延伸链、无规卷曲、β-转角组成。进化分析结果表明,巨桉EXP蛋白与毛果杨(Populus trichocarpa) EXP蛋白的进化关系接近。35个巨桉EXP基因在巨桉未成熟木质部、成熟叶片、韧皮部、茎尖、木质部以及幼叶组织中表达模式存在显著差异。[结论]EXP基因家族各成员的表达模式不同,Egr EXP17、Egr EXP18可能在巨桉木材形成过程中起重要作用。  相似文献   

17.
多纹豹蠹蛾在福建省一年一代,以幼虫在树干基部蛀道中越冬,幼虫19龄,历期313—321d,每树大多仅有一条幼虫和一个排粪孔;6月中旬为羽化高峰期,成虫具趋光性;7月上、中旬为孵化盛期。受害植物已知 20种,以木麻黄为主,被害株率最高达82%。可选用湿地松、柠檬桉为木麻黄的混交树种;杜绝带虫苗木造林;幼虫蛀入期对排粪孔喷注白僵菌,害虫死亡率86.7—98.3%,幼虫未蛀入时对嫩枝小喷溴菊酯或氧化乐果液剂,均可收到良好的防治效果。  相似文献   

18.
Six kinds of extracts drawn fromAjuga multiflora andA. multiflora var.brevispicata and A. multiflora var.serotina using methanol and acetone were used in this experiment to test their killing activity to the second instar larvae ofHyphantria cunea and their influence on its natural enemies. The average death rate caused by those extracts on the second instar larvae was 85.70%. The mortality rate caused by the extracts drawn with methanol was from 88.89% to 96.33%, which was significantly higher than that caused by acetone extracts. Those extracts were safe toTrichogramma dendrolimi, Coccinella septempunctata, the natural enemies ofH. cunea. We did not found any evidence shown that those extracts had any influence the emergence and the development ofT. dendrolimi. Those methanolic extracts gotten fromA. multiflora andA. multiflora var.brevispicata had no significant effects on the mortality of the larvae and adults ofC. septempunctata. Those extracts could be used in the control ofH. cunea safely. The research was sponsored by National Nature Science Fundation (39470586) (Responsible Editor: Chai Ruihai)  相似文献   

19.
对小果垂枝柏大痣小蜂的主要生物学特性进行观察研究,结果表明:小果垂枝柏大痣小蜂在云南省曲靖地区1 a发生1代,以幼虫越冬,翌年4月中旬开始化蛹;6月中旬开始羽化,6月下旬为羽化盛期;成虫产卵于当年生幼嫩小球果种子内,卵于6月中旬开始孵化;幼虫在种子内取食约10个月并随种子同步发育,一生仅取食1粒种子,无转移危害习性。成虫在上午6∶00—9∶00和下午12∶00—15∶00羽化最多,雌雄性比为0.9∶1,雌虫平均寿命为7.1 d,雄虫平均寿命为5.2 d。  相似文献   

20.
The sugar beet weevil, Bothynoderes punctiventris Germ. (Coleoptera: Curculionidae), is one of the most damaging pests of sugar beets in Turkey and has been traditionally controlled by application of large amounts of insecticides. The current study used laboratory microcosms to evaluate the possibility of using entomopathogenic nematodes as an alternative control method. The nematodes Steinernema feltiae (strain TUR-S3), Steinernema weiseri (BEY) and Heterorhabditis bacteriophora (TUR-H2) had previously been isolated from Turkey. Nematode-induced mortality generally increased as soil temperature increased from 15 to 25°C but decreased when larvae were located deeper in soil. Heterorhabditis bacteriophora caused the highest larval mortality at 25°C at all depths (5–20 cm). Steinernema feltiae and S. weiseri were more effective than H. bacteriophora at 15°C at all depths. Increasing the application rate of infective nematode dauer juveniles (DJs) affected the number of DJs that penetrated each insect larva and the number of DJs produced per insect. The highest production of DJs per larva occurred at application rates of 50 DJs/larva for S. feltiae and S. weiseri and 100 DJs/larva for H. bacteriophora. Reproduction decreased again at higher application rates. Heterorhabditis bacteriophora had the highest reproductive capability. The results indicate that S. feltiae and S. weiseri might be more effective against this pest early in the growing season when soil temperature is low and that H. bacteriophora might be more effective later in the season when temperature increases.  相似文献   

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