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1.
Savi's pine vole (Microtus savii) is a rodent species of the Cricetidae family, inhabiting southern European agroecosystems. It is considered to be the main cause of rodent‐attributed damage in Italy. To achieve an effective management, detailed knowledge of this species is needed. However, the available information about this species is fragmentary and incomplete. In this paper, the existing knowledge of Savi's pine vole taxonomy, reproduction, population dynamics, habitat and food preferences is reviewed in order to organise available information and identify priority areas of future research. Some of the changes in farming practices that have occurred in recent decades may have increased the impact of Savi's pine vole populations in crop fields. To manage this pest species effectively, an integrated strategy is recommended (involving habitat management, trapping and, when appropriate, the use of rodenticides). The apparent lack of cyclical population outbreaks and the relatively small litter size and long gestation and interpartum period of this species suggest that it could be more manageable than other vole species, while its strict herbivorous diet, stable population size in open habitats and wide distribution seem to indicate it as an ideal model species for risk assessment studies. © 2015 Society of Chemical Industry  相似文献   

2.
松材线虫Hsp70基因的克隆与原核表达   总被引:2,自引:0,他引:2  
 热激蛋白70(Hsp70)是已知热休克蛋白家族中最重要的-种, 它在细胞内的大量表达可以明显改善细胞的生存能力, 提高对环境胁迫或伤害的耐受性。采用RACE-PCR技术, 从松材线虫(Bursaphelenchus xylophilus)中克隆了Hsp70基因的全长cDNA序列(共2 061 bp)(GenBank登录号为:DQ785812)。其编码-个分子量为70 kD的642个氨基酸的蛋白序列, 含有3段Hsp70家族的签名序列。同源性分析表明, 氨基酸序列与其它真核生物的Hsp70序列具有很高的相似性, 并与秀丽隐杆线虫(Caenorhabditis elegans)热激蛋白70家族中的hsp-1基因编码的氨基酸序列更为相似。因此, 将克隆的松材线虫Hsp70基因命名为Bx-hsp-1。构建了-个原核表达载体Bx70pEASY-E1, 当IPTG终浓度为0.4~0.8 mmol/L时, 能诱导表达融合蛋白。Bx-hsp-1基因的克隆和表达, 将为松材线虫的生态适应性机理研究奠定基础。  相似文献   

3.
感染松材线虫病松树滑刃目线虫调查   总被引:4,自引:0,他引:4  
 本研究首次在全国范围内调查感染松材线虫病松树体内滑刃目线虫的种群组成,包括种类记述和数量组成分析。结果表明:在300份样品中共分离得到10种滑刃目线虫,隶属于3科、4属,其中有2个国内新记录种;它们是松材线虫、拟松材线虫、霍夫曼尼伞滑刃线虫、薄荷滑刃线虫、大核滑刃线虫、小麦长尾线虫(国内新记录种)、爱尔密那长尾线虫(国内新记录种)、李氏长尾线虫、吴氏长尾线虫和外滑刃科线虫一种;描述并且图示比较它们的形态特征。种群数量组成分析表明:松材线虫在感病松树体内占据绝对的优势,削弱了松树线虫群落组成的多样性,即线虫群落结构趋向单一化。研究还表明,利用长尾属线虫的捕食习性来控制中国松材线虫病的流行与危害值得进一步探索与研究。  相似文献   

4.
The threat from pests and pathogens to native and commercially planted forest trees is unprecedented and expected to increase under climate change. The degree to which forests respond to threats from pathogens depends on their adaptive capacity, which is determined largely by genetically controlled variation in susceptibility of the individual trees within them and the heritability and evolvability of this trait. The most significant current threat to the economically and ecologically important species Scots pine (Pinus sylvestris) is dothistroma needle blight (DNB), caused by the foliar pathogen Dothistroma septosporum. A progeny‐population trial of 4‐year‐old Scots pine trees, comprising six populations from native Caledonian pinewoods each with three to five families in seven blocks, was artificially inoculated using a single isolate of D. septosporum. Susceptibility to D. septosporum, assessed as the percentage of non‐green needles, was measured regularly over a period of 61 days following inoculation, during which plants were maintained in conditions ideal for DNB development (warm; high humidity; high leaf wetness). There were significant differences in susceptibility to D. septosporum among families indicating that variation in this trait is heritable, with high estimates of narrow‐sense heritability (0.38–0.75) and evolvability (genetic coefficient of variation, 23.47). It is concluded that native Scots pine populations contain sufficient genetic diversity to evolve lower susceptibility to D. septosporum through natural selection in response to increased prevalence of this pathogen.  相似文献   

5.
In Hebei Province of North China, forest was recovered with natural recruitment in plantations with large area of clear-cutting Chinese pine(Pinus tabuliformis). This study was aimed to demonstrate the dynamic characteristics of recruits during the natural recruitment. Both plot survey and the spatial point-pattern analysis were performed. Five developmental stages of natural recruitment were selected and studied, including 1 year before and 2, 5, 8, and 11 years after clear-cutting. Different slope aspects were also included. Natural recruitment was always dominated by Chinese pine with a proportion of higher than 90%. For plots of 1 year before clear-cutting on east-and north-facing slopes, recruit densities were 7886 and 5036 stems/hm2, the average heights were 0.78(±0.85) and 1.06(±1.15) m, and the average diameters at breast height(DBH) were 3.21(±1.38) and 2.91(±1.38) cm, respectively. After clear-cutting, recruit density was initially increased, then it was gradually declined with time; however, the variation of average DBH was contrary to that of recruit density. Both of them were no longer varied between 8 and 11 years after clear-cutting. The average height of recruits continued to increase after clear-cutting. For the plots of 11 years after clear-cutting on east-and north-facing slopes, average heights of recruits reached 2.00(±1.14) and 2.24(±1.20) m, respectively. The statuses of recruits on north-facing slopes were better than those on east-facing slopes after clear-cutting. Meanwhile, recruits on east-facing slopes were always aggregated at small scales, while spatial pattern of recruits varied with time on north-facing slopes. Moreover, forest was recovered more quickly by natural recruitment than by artificial afforestation after clear-cutting. The structural diversity was higher in naturally regenerated forests than in plantations of the same age. Our results demonstrated that clear-cutting of Chinese pine plantations recovered by natural recruitment has the potential to be an effective approach for establishing multifunctional forest.  相似文献   

6.
The effect of three types of cover crop Calapogonium mucunoides Desv., Centrosema pubescens Benth. and Pueraria phaseoloides (Rexb.) Benth., and hand-weeding on the growth and yield of Pinus caribaea var. hundurensis Barr and Golf were investigated after 42 months of planting. The costs and benefits of the four methods are evaluated and compared. Results show no significant differences in survival percentage, but show significant differences in mean height of trees after 15 months. Survival percentage, mean height, girth and basal area of trees, measured after 42 months, showed no significant difference between treatments. However, trees grown with C. mucunoides had the highest values of all four variables measured. Economic analysis shows that cost per hectare is higher for hand-weeding while cover cropping has a higher net present value of investment. The results demonstrate that cover cropping is a more profitable alternative to hand-weeding in weed control in pine plantations, and that C. mucunoides will be the best choice of the three cover crops studied. Critères de choix économiques pour des méthodes de désherbage des jeunes plantations de pins (Pinus caribaea var hundurensis Barr and Golf) Les effets de 3 sortes de couvert végétal (Calapo-gonium mucunoides Desv., Centrosema pubescens Benth. et Pueraria phaseoloides (Rexb.) Benth. et du desherbage manuel sur la croissance et le rendement de Pinus caribaea var. hundurensis Barr et Golf ont étéétudiés après 42 mois de plantation. Les coûts et profits des quatre méthodes sont estimés et comparés. Les résultats ne montrent pas de différences significatives dans le pourcentage de survie, mais en revanche les différences sont significatives sur la hauteur moyenne des arbres après 15 mois. Le pourcentage de survie la hauteur moyenne, la surface basale et la circonférence des arbres mesurés après 42 mois n'expriment pas de différence significative entre les traitements. Cependant, les arbres élevés avec C. mucunoides ont des valeurs plus élevées pour les quatre variables envisagées. L'analyse économique montre que le coût par hectare est plus élevé pour le dèsherbage, tandis que le couvert végétal a une plus grande valeur nette d'investissement. Les résultats démontrent que le couvert végétal est une alternative plus rentable que le dèsherbage manuel dans les plantations de pins et que C. mucunoides est le meilleur choix parmi les trois espèces étudiées. L'analyse économique montre que le coût par hectare est plus élevé pour le désherbage manuel, tandis que le couvert végétal a une plus grande valeur nette d'investissement. Les résultats démontrent que le couvert végétal est une alternative plus rentable que le désherbage manuel dans les plantations de pins et que C. mucunoides est le meilleur choix parmi les 3 espèces étudiées. Ökonomische Kriterien für die Unkrautbekämpfung in Kulturen von Pinus caribaea var. hundurensis Barr & Golf Die Wirkung von Bodendeckern (Calapogonium mucunoides Desv., Centrosema pubescens Benth., Pueraria phaseoloides (Rexb.) Benth., und mechanischer Unkrautbekämpfung (Jäten) auf das Wachstum und den Zuwachs von Pinus caribaea var. hundurensis Barr & Golfwurde 42 Monate nach der Pflanzung untersucht. Die Kosten und die Wirksamkeit der 4 Varianten wurden verglichen. Während hinsichtlich des Anwachsens keine Unterschiede bestanden, ergaben sich für die mittlere Wuchshöhe der Bäume nach 15 Monaten signifikante Unterschiede. Überlebensrate, mittlere Höhe und Stammumfang waren 42 Monate nach der Pflanzung nicht significant verschieden, doch waren diese Parameter bei Calapogonium mucunoides am höchsten. Die Hektarkosten waren für die mechanische Unkrautbekämpfung höher als für die Bepflanzung mit Bodendeckern, die sich damit für Kiefernkulturen als wirtschaftlicher erwies. Von den 3 Bodendeckern ist die erstgenannte Art vorzuziehen.  相似文献   

7.
Pine wilt disease (PWD), recently introduced into Europe, is caused by the pine wood nematode (PWN) Bursaphelenchus xylophilus and is a devastating illness that affects mainly pine trees. It is known that the PWN is capable of infecting other conifers; however, there is currently no information on which other plant species may be susceptible to PWD. In this study, the potential susceptibility of two common species of European forests, Picea abies and Cupressus lusitanica, to PWN was assessed through the monitoring of visual external symptoms, dimension and localization of the nematode population in stems, quantification of total chlorophyll, total soluble phenolics and lignin, at 7, 14, 21 and 28 days after inoculation. The degree of susceptibility was established through the comparison of symptoms with Pinus pinaster, a well‐known PWN host. Furthermore, the stem ultrastructure of P. abies, C. lusitanica and Pn. pinaster was analysed by scanning electron microscopy. The results suggest that P. abies and C. lusitanica are resistant to PWN, and that lignin biosynthesis in these species is affected at an early stage of the infestation. Nevertheless, P. abies seems to be a compatible host that could act as a repository for PWN.  相似文献   

8.
20-(S)-喜树碱7-C-取代衍生物的合成及杀松材线虫活性研究   总被引:1,自引:1,他引:0  
为研究喜树碱(CPT)类化合物的杀线虫活性,以喜树碱为原料,经烷基化、氧化、酯化等步骤合成了13个7-C-取代的20-(S)-喜树碱衍生物,其中化合物 14 未见文献报道,所有衍生物的结构经红外光谱(FT-IR)、核磁共振氢谱(1H NMR)和液-质联用(LC-MS)等分析手段进行了表征。采用浸渍法测定了化合物对松材线虫Bursaphelenchus xylophilus的毒杀活性。结果表明:与母体化合物喜树碱相比,7-C-取代的20-(S)-喜树碱衍生物具有更强的杀线虫活性,其中化合物7-苄基喜树碱、7-甲酰基喜树碱、7-苯甲酰氧甲基喜树碱在24 h的致死中浓度(LC50值)分别为2.28、2.21和1.37 mg/L,明显高于母体化合物喜树碱的LC50值12.18 mg /L。  相似文献   

9.
松材线虫侵染对马尾松、黑松水分及其相关代谢的影响   总被引:7,自引:0,他引:7  
 以盆栽马尾松(Pinus massoniana)幼苗和离体水培黑松(P.thunbergii)、马尾松为材料,研究了松材线虫(Bursaphe-lenchus xylophilus)侵染对寄主水分、游离脯氨酸及叶绿素含量的影响以及由此引起的幼苗萎蔫与干旱萎蔫间的差异。松苗和离体枝接种松材线虫后,茎部相对含水量逐渐下降,早期下降缓慢,中后期加快。叶片变化滞后于茎部,相对含水量的明显下降发生在叶片褐变萎蔫症状出现之后(病害发展后期)。游离脯氨酸含量、叶绿素含量变化完全随叶片相对含水量的变化而变化。水分状况是影响受侵植株叶片脯氨酸和叶绿素含量的决定因子。自然干旱枯萎和由松材线虫侵染引起枯萎的松幼苗,两者从枯萎方式到茎、叶相对含水量的变化均存在显著差异。  相似文献   

10.
松材线虫种群遗传多样性AFLP标记的建立及其应用   总被引:2,自引:0,他引:2  
 松材线虫是极具危险性的外来入侵生物,其引起的松材线虫病,目前正在我国部分地区迅速扩展和蔓延,对我国林业生产造成了严重的经济损失。开展松材线虫的种群遗传学研究,是了解其成功入侵和爆发成灾内在机理的重要途径。但迄今为止,尚未找到很有效的分子标记方法来检测松材线虫入侵种群的遗传变异。本文采用AFLP分子标记技术,通过对各反应体系和反应条件的优化及对多态性引物组合的筛选,成功地建立了松材线虫的AFLP分子标记实验体系,并筛选出52对高效多态性的引物组合。应用4对引物对27个松材线虫种群样品进行遗传多样性检测,结果表明,AFLP是进行松材线虫种群遗传学研究的一种很灵敏和可靠的分子标记。此外,本文还对AFLP技术在松材线虫研究中的应用前景进行了讨论。  相似文献   

11.
Along with sulfate turpentine, the essential oils obtained by steam distillation from nine plant species naturally grown in Turkish forests were tested at three different concentrations to evaluate their effectiveness against the larvae of pine processionary moth (Thaumetopoea pityocampa Schiff). The results indicated that the essential oils from the nine species and sulfate turpentine were effective against the larvae of T pityocampa. The most effective essential oil in the control of the larvae was steam-distilled wood turpentine, followed by thyme herb oil, juniper berry oil, laurel leaf oil, lavender flower oil, eucalyptus leaf oil, lavender leaf oil, cypress berry oil, essential oil of styrax and sulfate turpentine, respectively, in terms of mean mortality time. It is therefore feasible to use these essential oils as environment-friendly insecticides in the control of T pityocampa.  相似文献   

12.
13.
Information is presented on new occurrences of two homopteran pests,Matsucoccus josephi Bodenheimer et Harpaz (Matsucoccidae) andPineus pini (Macquart) (Adelgidae), in Israel, Jordan and southern Lebanon.M. josephi occurs in Israel in almost all natural relicts of Aleppo pine (Pinus halepensis). It infests all plantations of Aleppo pine, brutia pine (Pinus brutia ssp.brutia) and Eldar pine (P. brutia ssp.eldarica) north of 31°12′ lat. N. Heavy damage has been observed in the Judean Foothills, Judean Mts. and northern Samaria.M. josephi and its specific predator,Elatophilus hebraicus Pericart (Hemiptera: Anthocoridae), are recorded for the first time in Jordan and southern Lebanon. The scale was found in all visited Aleppo pine and brutia pine stands in Jordan and in natural and planted brutia pine in southeastern Lebanon. Damage byM. josephi in Jordan was observed only in young plantations of Aleppo pine; in Lebanon no signs of injury were recorded.P. pini was found for the first time in Jordan, where it causes severe damage to young stands of Aleppo pine and stone pine (Pinus pinea). Contribution from the Agricultural Research Organization. No. 1225-E, 1993 series.  相似文献   

14.
杨笑如 《江西植保》2005,28(3):97-99
云南松毛虫是福建省沿海地区湿地松的重要害虫之一。该虫一年发生1代,以卵越冬,卵于翌年2月下旬孵化,幼虫7龄,历期158d~195d,以取食嫩针叶为主,幼虫老熟时下树,藏于草丛里或树干基部,在枯枝落叶中结茧化蛹,预蛹期50d~70d,成虫寿命5d~10d.其发生与林分的林木组成、气候、天敌等因子密切相关.试验表明:用25%灭幼脲3号,白僵菌与0.4%氰戊菊酯粉剂按4︰1混合制成的粉炮防治幼虫,有良好效果。  相似文献   

15.
为了探究长林小蠹Hylurgus ligniperda(Fabricius)触角上感器的类型和数量,为进一步探索其对化学信号的感受机制奠定基础,利用扫描电镜技术对长林小蠹雌雄成虫的触角感器进行观察。结果表明:长林小蠹触角上存在5种类型的感器和少量腺孔,包括毛形感器(ST-Ⅰ、 ST-Ⅱ、 ST-Ⅲ亚型)、锯齿形感器(SZ-Ⅰ、 SZ-Ⅱ、 SZ-Ⅲ亚型)、刺形感器(Sch)、腔锥形感器(Sco)和芽形感器(BS)。毛形感器约占总感器数的61%,锯齿形感器在触角的每一节均有分布,占感器总数的24.7%,刺形感器分布在柄节基部和梗节,腔锥形感器只少量散生在部分毛形感器带上,数量约占4.1%,鞭节端部分布有0~3个芽形感器,且有个体差异。长林小蠹雌雄成虫间触角感器的结构和类型无明显差异,雌虫ST-Ⅰ比例稍多,雄虫ST-Ⅱ比例稍多。  相似文献   

16.
17.
ABSTRACT A dominant gene for resistance to white pine blister was indicated by Mendelian segregation in full-sib families of western white pine parent trees selected for phenotypic resistance in six heavily infected stands in the Western Cascades of Oregon and Washington. Seedlings were artificially inoculated three times between 1959 and 1964 and observed for development of stem infection. Segregation at this locus (Cr2) occurred in only two of the six parent populations sampled: one a natural stand, Champion Mine (CM), and the other a plantation of unknown seed origin. At CM, reduced penetrance of this gene was expressed by altered Mendelian ratios (mostly less-than-expected resistant phenotypes) in families of specific combinations of certain parents, indicating the presence of modifier genes with effects that ranged from mild to almost complete suppression of Cr2. Between 1968 and 1994, an apparent shift in virulence at CM caused all of the resistant selections to become infected and die. Recent inoculations of many of the same or related families from these parents, made from grafted ramets in a seed orchard, showed that Cr2 conditions a classical hypersensitive reaction (HR) in needle tissues, the primary infection courts. In the latter tests, seedlings were challenged with wild-type and four other sources of inoculum at and near CM that were also suspected of having wider virulence than wild type. No seedlings segregating for HR that were inoculated with wild type subsequently developed stem symptoms, but the other inocula induced both susceptible and HR needle spots on Cr2- genotypes, and many of these seedlings did develop stem infections. This implied that spore genotypes with specific virulence to Cr2 are carried in these inocula.  相似文献   

18.
Fusarium circinatum is a highly virulent invasive pathogen that causes the disease commonly known as pine pitch canker (PPC). On mature trees, the most common symptoms of PPC include resin bleeding, resinous cankers, wilting of needles and dieback. In nurseries the main symptoms are yellowish needles, and wilting of foliage and shoots. PPC is considered one of the most important diseases of conifers globally and at least 60 species of Pinus along with Pseudotsuga menziesii are known to be susceptible. Quarantine regulations are crucial to minimize the risk of new introductions into disease-free countries. However, if these measures fail, implementation of environmentally friendly control methods is currently encouraged in an integrated management approach that minimizes the use of chemicals in forests. This review therefore summarizes current knowledge of biological control using endophytic fungi, bacteria and viruses, and other environmentally friendly methods to control PPC, including thermotherapy, natural products with fungicidal effects, promoters of innate host resistance mechanisms and breeding for resistance. Key research gaps to be addressed for improvement of effective management of this disease are discussed.  相似文献   

19.
The seasonal occurrence, behavior and gallery system of seven sympatric pine bark beetles were examined at two sites, using trap-logs and trap-trees ofPinus halepensis. Two groups of beetles were recognized:(a) Tomicus destruens, Hylurgus micklitzi andHylastes linearis, which are monogamous, univoltine, breed during the winter and early spring, and prefer the lower section of the tree;H. micklitzi andH. linearis tend to infest the main root system,(b) Orthotomicus erosus, Pityogenes calcaratus, Carphoborus minimus andCrypturgus mediterraneus, which are polygamous, multivoltine, and breed from spring to autumn.O. erosus usually infests the lower stem sections,P. calcaratus occupies the thin smooth bark aboveO. erosus, andC. minimus develops on the top stem.Cr. mediterraneus lives in the mines and egg tunnels of the other species and uses their gallery entrance holes. Occupation of different stem sections by the beetles, and beetle damage as related to tree age are discussed.  相似文献   

20.
ABSTRACT The distribution and frequency of the Cr2 gene for resistance to white pine blister rust (Cronartium ribicola) in western white pine (Pinus monticola) was surveyed in natural populations of the host by inoculation of open-pollinated seedlings from 687 individual seed parents from throughout most of the species' range. Because Cr2 is dominant and results in a conspicuous hypersensitive reaction (HR) in pine needles, the phenotype can readily be detected in offspring of susceptible seed parents fertilized by unknown Cr2 donors in the ambient pollen cloud. Gametic frequencies of Cr2 were thus determined as the proportion of total challenged seedlings that were pollen receptors exhibiting the Cr2 phenotype. Zygotic frequencies, the proportion of seed parents with progeny that segregated in Mendelian ratios for the Cr2 phenotype to the total number of parents, were a complementary, though less precise, measure. Cr2 frequency was rare overall, ranging from 0.004 to 0.008 in the Sierra Nevada to about 0.001 in the central Cascade Range; it was undetectable further north in the Cascades, as well as in the Rocky Mountains and Coast Mountains of the United States and Canada. The diminishing frequency of Cr2 from the southern and central Sierra Nevada northward mirrors that of Cr1 in sugar pine (P. lambertiana) and points to this region as the origin of both genes. We rationalize that this coincidence may have resulted from protection that these genes may have conferred on both species to an endemic pine stem rust congeneric with C. ribicola (C. occidentale) in recent geologic epochs.  相似文献   

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