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1.
苦豆草生物碱对柳蓝叶甲的拒食作用 总被引：1，自引：0，他引：1
研究苦豆草生物碱对柳蓝叶甲取食的影响.结果表明:苦豆草生物碱总碱及其单体对柳蓝叶甲具有较强的拒食作用,且随着浓度的升高拒食作用增强.在选择性取食条件下,随着总碱处理浓度的升高,试虫对处理叶的取食量迅速下降;而对未处理叶的取食量没有显著的差异,但随着处理浓度的升高,总取食量明显下降.在供试的6种生物碱单体中,苦豆碱和槐胺碱对柳蓝叶甲的拒食活性较强.其中处理浓度为5 mg·mL-1时,在选择性取食条件下,苦豆碱的拒食率高达99.4%,而在非选择性取食条件下,则以槐胺碱的拒食活性较强,达91.7%. 相似文献
2.
在实验室条件下研究苦豆子生物碱对柳蓝叶甲产卵行为的影响.结果表明:苦豆子不同生物碱对柳蓝叶甲成虫的毒力不同,因而对柳蓝叶甲产卵行为的影响也不同.在选择性取食条件下,5 mg·mL-1苦豆子生物碱即对柳蓝叶甲成虫产卵具有强烈的抑制作用,槐果碱、苦参碱、苦豆碱和总碱对柳蓝叶甲成虫产卵抑制率分别为61.2％,61.3％,46.3％和53.2％.槐定碱和氧化苦参碱对产卵的抑制效果较差,抑制率仅为6.4％和5.3％.在选择性条件下虽然苦参碱对柳蓝叶甲的产卵驱避率高达54％,但各生物碱单体之间无显著差异.在非选择性取食条件下,苦豆子生物碱对柳蓝叶甲成虫产卵的抑制作用更为强烈,用总碱、苦豆碱、氧化苦参碱和槐定碱处理后的叶片饲喂12天,其产卵抑制率平均分别为82.2％,74.4％,55.6％和33.6％.当用毒力较弱的氧化苦参碱、苦豆碱或槐定碱处理时,柳蓝叶甲雌虫倾向于把卵产在非生物碱处理的叶片上;这些生物碱处理对柳蓝叶甲卵块大小无显著影响但产卵量明显受抑制.当用毒力较强的槐胺碱或槐果碱处理时,柳蓝叶甲的产卵量和卵块大小均受明显影响. 相似文献
4.
柳蓝叶甲生物学特性观察及防治试验 总被引：2，自引：0，他引：2
通过野外采集柳蓝叶甲(Plagiodera versicolora)成虫进行室内饲养及野外生物学特性观察,并采用5种商品农药对室内饲养的成虫和幼虫进行了毒杀试验,结果表明,柳蓝叶甲在浙江丽水1a发生9代,以成虫在杂草丛、落叶层、土壤缝隙中越冬.翌年3月上旬出蛰活动,5月至10月为成、幼虫危害盛期,11月上旬开始越冬.室内农药试验表明,480 g/L毒死蜱乳油1000倍液对柳蓝叶甲成、幼虫都有很好的防治效果,死亡率可达100%;4.5%绿爽跳甲高效型微乳剂2 000倍液、1.8%阿维菌素乳油4 000倍液对柳蓝叶甲幼虫有较好的防治效果,死亡率分别为100%、89.3%,但对成虫防治效果不理想,害虫死亡率仅分别为44.9%、6.9%;20%氰戊菊酯乳油5 000倍液、3%啶虫脒微乳剂2000倍液对成、幼虫的防治效果均不理想. 相似文献
5.
海芒果、夹竹桃、黄婵、乌桕对柳蓝叶甲的毒杀活性 总被引：2，自引：0，他引：2
用索氏提取法获得了海芒果Cerbera manghas、夹竹桃Nerium indicum、黄婵Alamanda cathartica和乌桕Sapium sebiferum的叶片乙醇提取物,在室内分别测定了这4种植物不同浓度提取物对柳蓝叶甲（plagiodera versicolora）的防治效果,结果表明：4种植物提取液原液的校正死亡率最终均达到100%,尤以夹竹桃、海芒果处理的效果最为显著,其提取液处理后叶甲的校正死亡率都高于乌桕和黄婵处理的,仅1天后,供试昆虫的校正死亡率就达到100%。海芒果和夹竹桃提取物处理后叶甲的校正死亡率曲线呈现平稳上升的趋势,乌桕和黄婵处理后叶甲的校正死亡率曲线趋向于平直。试验结果为进一步在生产实践中有效应用植物杀虫剂提供参考依据。 相似文献
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7.
柳蓝叶甲(PlagiodernversicoloraLaichartig)又名柳蓝金花虫。分布于山东、河南、安徽、辽宁、吉林等省,幼虫啃食杨树、柳树叶背叶肉,成虫取食嫩叶,呈缺刻或穿孔,常以初春发生量大,严重影响苗木和幼树生长。1形态特征1.1成虫体椭园形,深蓝色,具金属光泽,雌虫体长4.5-5.0mm,体宽 相似文献
8.
柳蓝叶甲[Plagiodera versicolora(Laichart)]又名柳蓝金花虫,以成、幼虫为害柳树叶片,亦加害杨树,我省发生普遍,淮北和沿淮一带较严重。1980—81年室内饲养、圃地定点观察和野外调查表明,该虫在我省每年8—9代,以成虫在落叶层、杂草丛、石块下或土中越冬,翌年4月上旬日平均温度12℃时出蛰取食活动,3—5天 相似文献
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10.
以含有Cry3Aa基因的重组质粒pBCC3为基础,利用PCR和DNA重组技术,从pBCC3中克隆出抗虫基因Cry3Aa,将其正向插入载体pCAMBIA1305的CaMV35S启动子和NOS终止子之间,构建成pCAMBIA1305-Cry3Aa植物表达载体,并导入根癌农杆菌EHA105。采用农杆菌介导的遗传转化法,将Cry3Aa基因转入已转Cry1Ac+API基因的741毛白杨无性系pB29中,获得转双Bt基因的741杨。在含潮霉素的培养基中进行多次继代筛选,获得抗性稳定的无性系9个,编号为pCCA1—pCCA9。采用特异引物分别对转基因植株进行PCR检测,结果显示Cry1Ac基因稳定存在于pB29中,Cry3Aa基因已整合到各无性系的基因组DNA中。ELISA毒蛋白检测,转基因株系都有Cry1Ac和Cry3Aa杀虫蛋白表达。用转基因植株叶片进行柳蓝叶甲(鞘翅目)和美国白蛾(鳞翅目)室内饲虫试验结果表明,转基因植株具有双抗性。根据对测试昆虫的致死率划分高中低3个抗性水平,其中pCCA2,pCCA5,pCCA6,pCCA9具有双高抗;pCCA3,pCCA4和pCCA7对柳蓝叶甲表现出中、低抗性,对美国白蛾则高抗;而pCCA1表现对美国白蛾的极低抗性,对柳蓝叶甲则高抗。 相似文献
11.
《Scandinavian Journal of Forest Research》2012,27(5):427-435
In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads. 相似文献
12.
《Scandinavian Journal of Forest Research》2012,27(3):206-217
The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage. 相似文献
13.
《Scandinavian Journal of Forest Research》2012,27(1):53-61
This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland. 相似文献
14.
《Scandinavian Journal of Forest Research》2012,27(1):15-27
The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions. 相似文献
15.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。 相似文献
16.
《Scandinavian Journal of Forest Research》2012,27(2):131-138
The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):472-479
Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken. 相似文献
19.
Srisuda Thippayarugs Banyong Toomsan Patma Vityakon Viriya Limpinuntana Aran Patanothai Georg Cadisch 《Agroforestry Systems》2008,72(2):137-148
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic
or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts
(stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea
(Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content
as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest
N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized
to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea,
largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for
N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant
components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N
released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures
were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality
components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in
the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols.
Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest
age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its
components are mixed. 相似文献
20.
A. Rigueiro-Rodríguez M. R. Mosquera-Losada E. Gatica-Trabanini 《Agroforestry Systems》2000,48(3):245-256
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste
disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization,
(2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two
pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea
(Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect
on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage
sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but
affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral
systems.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献