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1.
松梢象对红松萜烯类挥发物的触角电位及行为反应   总被引:1,自引:0,他引:1  
本文研究了松梢象对寄主红松挥发物组分S型α一蒎烯、R型α一蒎烯、卢一蒎烯、β一月桂烯、罗勒烯、莰烯、3一蒈烯及反一柠檬烯8种挥发物,在0.0004、0.004、0.04、0.4及0.8mol/L浓度下的触角电位反应及行为反应。结果表明:这8种挥发物单体在各浓度下均能引起松梢象的触角电位(EAG)反应,且相同挥发物EAG...  相似文献   
2.
Bark beetle species in natural stands of spruce, Picea crassifolia (Kom.) were investigated in Maixiu Forest Park, Qinghai Province, northwest China, during 2005 and 2007. Two pioneer Ips species, Ips nitidus Eggers and Ips shangrila Cognato and Sun were found. I. nitidus occurs naturally in northwest China. I. shangrila is a new species in the world. In the past, it was confused with I. mannsfeldi Wachtl in China. The damage of these two Ips species has been very severe in Maixiu and the morphological and bio-logical characteristics were studied. I. nitidus starts to fly in early May and prefers the mid to lower part of the host tree to colonize as its habitat. I. shangrila always infests from the top of the trunk, especially in branches larger than 3 cm in diameter in the crowns and sometimes even colonizes entire young trees. The two Ips species are the most destructive secondary bark beetles on P. crassifolia and always cause mortality of trees by their cooperation.  相似文献   
3.
2005~2007年间,在黑龙江省朗乡林业局采用林间定期取样调查的方法,通过测量不同发育阶段幼虫的头宽,确定了松梢象甲幼虫的龄数;通过统计各龄幼虫数量和发育进度,用期距法确定了各龄幼虫发生盛期,并为当地松梢象甲的生产防治提出了最佳防治时间。  相似文献   
4.
光臀八齿小蠹是"三江源"隆务河流域天然林区危害云杉林的先锋虫种和优势种,严重威胁着三江源自然保护区麦秀核心区的云杉林。本文总结了近几年来对光臀八齿小蠹生活史、性的关系和交配方式、坑道、越冬、危害特点等习性系统的观察研究。  相似文献   
5.
抽样调查黑龙江省伊春地区上甘岭林业局2013年度阔叶红松混交林遭受松梢象甲危害的24个林班、59个小班内177块样地的立地和林分因子、受灾情况等,计算有虫株率、虫口密度、Simpson多样性指数,分析阔叶红松混交林立地因子和林分因子对松梢象甲发生及危害的影响。结果表明:在上甘岭林业局阔叶红松混交林中,南坡受松梢象甲的危害较北坡严重,南坡虫害发生数是北坡的189.80%,占总有虫样方的52.54%,为主要受灾区域;将受灾样地的有虫株率与郁闭度值进行一元二次方程拟合,y=–12.689x~2–11.713x+27.843,R~2=0.666 4;将受灾样地的有虫株率与Simpson指数进行一元二次方程拟合,y=0.001 3x~2–0.060 4x+1.084 1,R~2=0.720 8;随着Simpson多样性指数的增加和郁闭度的增加,有虫株率有明显降低的趋势。松梢象甲虫口密度与受灾林地的乔木平均树高和平均胸径呈显著相关。  相似文献   
6.
红松挥发性物质与松梢象危害的关系   总被引:1,自引:0,他引:1  
采用自动顶空进样与GC-MS联用技术,分析了被松梢象(Pissodes nitinus Roelofs)危害的红松主梢、健康红松(Pinus koraiensis Sieb.et Zucc.)主梢以及健康红松侧梢的挥发性物质成分,共发现22种挥发性物质。无论是主梢和侧梢,松芽挥发物的成分多于松针和松皮的挥发物;健康主梢与受害主梢挥发物的种类无差异,但与红松侧梢相比,红松主梢松芽中含有7种特有的挥发性物质,即α-水芹烯;1-甲基-4(1甲基亚乙基)苯;1,1-二甲基-3-甲基-1,3-丁二炔基环丙烷;十一烷;1,7,7-三甲基-乙酸-双环庚烷;α-胡椒烯;β-荜澄茄油烯。  相似文献   
7.
通过多年对松黄星象(Pissodes nitidus Rodlofs)虫情系统调查,初步弄清了松黄星象在伊春林区的发生规律,为更好地防治松黄星象提供依据。  相似文献   
8.
】大足鼠6月和10月高峰期的数量与上年3月的种群数量、性比和年龄结构有关。本文建立了线性回归,逐步回归和模糊相关的关系式。其中,模糊相关模型能最好地拟合原始数据,可作为预报手段  相似文献   
9.
Fertility control has been identified by studies in the laboratory and the field as a more appropriate and long‐term control strategy for rodent pests than lethal control. In this study, we investigated the effects of quinestrol on mass of reproductive organs and on social behaviors in female and male Himalayan field rats (Rattus nitidus). A total of 16 adult females and 16 adult males were randomly assigned to 4 groups. One male and one female group were fed rice with 0.005% quinestrol by weight for 7 days, and another 2 groups were fed rice only. After 7 days, rats were assigned to 10 min dyadic encounters between groups, and investigation, aggression, defense and attack latency were quantified. All animals were killed on day 10, and reproductive organs were dissected and weighed. Dyadic encounter data showed that there were obvious changes in social behaviors of quinestrol‐treated rats. Quinestrol significantly inhibited the investigative behavior of quinestrol‐treated males toward control females in Rattus nitidus, but seldom affected investigation between control males and quinestrol‐treated females. Aggression of control females toward quinestrol‐treated males was higher than that of quinestrol‐treated females, and defense of quinestrol‐treated males toward control females was more remarkable than that of control males. Quinestrol remarkably decreased wet masses of epididymis and spermotophore in males and ovaries in females, but had no effect on wet masses of testes and uteri after quinestrol treatment. These results indicate that the anti‐fertility effects of quinestrol on R. nitidus are attributed to not only suppressing reproductive organs but also impacting social behaviors associated with territory defense and mate choice.  相似文献   
10.
杨帆 《安徽农业科学》2008,36(7):2774-2776
[目的]为光泽黄颡鱼的养殖结构优化及其运输提供理论依据。[方法]利用静水方法研究温度变化对光泽黄颡鱼幼鱼耗氧率和窒息点的影响,探索鱼类呼吸代谢受环境变化影响的生理机制。[结果]不同体重光泽黄颡鱼幼鱼的耗氧率存在差异,体重较小的鱼的平均耗氧率较高,且白天平均耗氧率高于晚上。在11~29℃温度范围内,光泽黄颡鱼幼鱼耗氧率与温度呈显著的线性正相关,并且呈现曲线上升的趋势,其曲线回归方程为y=0.002 7x2-0.067 4x+0.516 5。光泽黄颡鱼幼鱼窒息点与体重和温度有一定关系。[结论]当温度为23~26℃时,光泽黄颡鱼幼窒息点最低,此时其生理代谢状态最佳,耐氧能力增强。  相似文献   
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