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1.
食品安全已成为当今社会广受关注的问题.尽管国内的一些学者就阿里山潜蝇茧蜂[Fopius arisanus(Sonan)]和橘小实蝇SIT技术分别开展了不同程度的研究,然而关于应用该蜂和不育雄虫对橘小实蝇[Bactrocera dorsalis (Hendel)]进行田间联合防治的研究还未见相关报道.为此,为探讨天敌昆虫和雄性不育技术对橘小实蝇的田间综合治理(IPM)技术,开展了阿里山潜蝇茧蜂和橘小实蝇不育雄虫的田间释放试验:首先应用性引诱剂降低田间野生雄虫数量;而后,释放橘小实蝇不育雄虫,进一步降低田间橘小实蝇种群数量;最后,释放阿里山潜蝇茧蜂对田间残余的橘小实蝇卵进行追踪寄生,以达到持续控制的目的.通过监测整个防控期田间橘小实蝇的种群数量以及果实受害率和防治效果作为评价指标评价该防治方法的综合防治效果.结果表明:应用阿里山潜蝇茧蜂、橘小实蝇不育雄虫并配合引诱剂的综合措施对橘小实蝇的种群数量有明显控制作用,田间总体防治效果可达90%左右.此外,提出完善橘小实蝇田间防控措施的建议,并提出该研究的不足以及有待进一步开展研究的方向.  相似文献   

2.
Using starch gel and polyacrylamide gel electrophoresis, the genetic diversity of 19 populations of black locust (Robinia pseudoacacia L.) distributed in China has been evaluated based on seven allozyme systems. Among the 14 enzyme loci studied, 12 of them showed polymorphic, giving a total of 40 alleles. The average allelic number (A) and the average effective allelic number (Ae) were 3.004 and 2.178, whereas the average of expected heterozygosity (He) and the observed heterozygosity (Ho) were 0.525 and 0.440, respectively. The total genetic differentiation (H T ) in the 19 populations tested was 0.536, including 0.515 within population (H S ) and 0.021 among populations (D ST ). The mean coefficient of genetic differentiation (G ST ) was 0.038, indicating that 3.8% of genetic differentiation was resulted from the populations, and the rest from those within the population. The genetic distance among the 19 populations was small, ranging from 0.015 to 0.065. Cluster analysis based on AVERAGE showed that populations with closer geographical distribution had higher genetic similarity than that in populations with far away distribution. There was no evident geographic differentiation pattern in Chinese black locust populations at a biochemical level.  相似文献   

3.
球孢白僵菌对烟粉虱后代生命表参数的亚致死影响   总被引:3,自引:1,他引:2  
【目的】关于昆虫病原真菌对昆虫生命表亚致死影响的研究较少,而由真菌侵染所产生的亚致死影响对于寄主昆虫的种群动力学至关重要,并最终影响着目标昆虫的害虫地位。论文旨在比较烟粉虱(Bemisia tabaci)亲代3龄若虫经球孢白僵菌(Beauveria bassiana)处理及对照子代种群的生命表参数,探讨球孢白僵菌对烟粉虱生命表参数的亚致死影响。【方法】应用年龄-阶段两性生命表分析经球孢白僵菌处理的烟粉虱后代的发育历期、存活率和繁殖率数据,以蒸馏水处理的个体作为对照。应用bootstrap方法计算种群生长参数的平均数和标准误;采用t-test比较分析球孢白僵菌处理组和对照组烟粉虱的种群参数、发育历期和繁殖力间的差异。【结果】球孢白僵菌处理的烟粉虱与对照之间在成虫前期、总产卵前期、1-4龄若虫存活率和生命表参数上存在着显著差异。与对照处理的烟粉虱成虫前期(20.59 d)相比,亲代接种球孢白僵菌使后代个体的成虫前期显著延长(26.58 d)。经球孢白僵菌处理的烟粉虱后代存活率(0.195)要比对照个体(0.76)低。球孢白僵菌处理烟粉虱后代种群的内禀增长率(r)、周限增长率(λ)、净增殖率(R0)、平均世代时间(T)和总繁殖率(GRR)分别为0.063 d-1 、1.065 d-1、6.85,30.613 d和41.883,而对照烟粉虱后代种群的上述参数分别为0.137 d-1 、1.147 d-1、33.443、25.575 d和51.44。【结论】亲代经球孢白僵菌处理的烟粉虱其子代种群增长要比对照组慢,死亡率高,但生殖能力并无显著性影响。该研究可为了解昆虫病原真菌对烟粉虱的长期影响提供理论依据。  相似文献   

4.
福州、三明野生蕉种群遗传多样性的RAPD分析   总被引:1,自引:0,他引:1  
应用RAPD分子标记对采自福州、三明的2个香蕉野生居群共37个个体进行遗传多样性分析.结果表明:两居群的遗传多样性水平差异不大,三明和福州两居群多态位点百分率分别为71.97%和83.12%;Ne i′s基因多样性指数分别为0.4110和0.2399;Shannon信息多样性指数分别为0.5995和0.4003.两地野生居群的遗传多样性水平较高,居群间产生的遗传分化小,居群内的遗传分化较大.在UPGMA聚类图中,除个别样本外,2个居群的个体按居群各自聚在一起,与两地野生蕉原生境考察结果一致.  相似文献   

5.
南方某矿区土壤镉污染及作物健康风险研究   总被引:2,自引:0,他引:2  
为了评估南方某县土壤镉污染情况、量化当地不同作物镉含量并对不同人群健康风险进行评估,从该县3个镇采集135份土壤样本,入户采集128份自产大米样本,种植区采集7份脐橙样本,对其中镉含量进行测定。结果表明,3镇采集土壤样品镉超标率分别为41.67%、28.81%和21.62%,地累积指数计算得到该县68.9%的土壤样本受到不同程度的镉污染,大米镉含量超标率分别为48.57%、34.48%、8.82%。而脐橙果肉样品中镉含量较低,远低于0.05 mg·kg-1。计算不同作物的危害商数(HQ)可得,食用自产大米的危害商数(HQ)值普遍大于1,风险较高,而食用脐橙果肉产生的健康风险低。种植脐橙具有一定的经济效益,且当地具有脐橙适宜的生长条件,故考虑在重污染区种植脐橙取代种植水稻。  相似文献   

6.
对吉富品系尼罗罗非鱼(Oreochromis niloticus)不同世代选育群体D-loop序列进行测定和分析,47个样本经重排比较后获得902 bp的同源序列。共检测到225个变异位点,占分析位点数的24.94%。同源序列中多态位点比例随着选育世代数的累进,呈现出降低的趋势。核苷酸多样性指数也呈现出同样的降低趋势,F0、F6、F7、F8、F9分别为0.074 02、0.068 72、0.064 15、0.049 52、0.044 55。多态位点比例、核苷酸多样性指数在不同世代间的变化趋势一致表明,随选育的进展,选育群体逐步纯化。选育基础群体F0与F6、F7、F8、F9之间的遗传距离呈增大趋势,表明较短时间内的人为选择可以造成与长期地理隔离效应相当的群体遗传分化。  相似文献   

7.
【目的】解决在农业环境中识别脐橙的目标区域存在的噪声干扰、检测效果不理想等问题。【方法】提出一种基于小波变换与Otsu阈值去噪的脐橙识别方法。首先选择较好的对比度,建立有利于图像分割的YCbCr颜色模型;然后设计一种基于Otsu阈值去噪的脐橙检测算法,进而减少脐橙分割区域的噪声干扰;最后提出质心补圆法确定脐橙在图像中的位置,并在原始图像中显示检测结果。【结果】泛青色和橙色脐橙识别率分别为87.10%和94.18%,顺光和逆光情况下脐橙识别率分别为92.96%和90.15%,遮挡和未遮挡情况下脐橙识别率分别为90.82%和93.18%,总识别率为92.07%。【结论】该方法环境适应性强,适用于农业环境下不同遮挡、光照和表皮颜色情况的脐橙图像识别处理。  相似文献   

8.
The level of genetic differentiation, gene flow and the relationship between geographical distance and genetic differentiation among six sheep populations of Mongolian group in China (Tong sheep, small-tailed Han sheep, Hu sheep, Tan sheep, Ujumuqin sheep and Bayinbuluk sheep) were analyzed using seven microsatellites. The trees were constructed from diversity coefficient (DC) distances among the six sheep populations. The overall heterozygote deficit across all the populations (F it) was between 0.167 (OarAE101) and 0.044 (MAF33). The over-all significant deficit of heterozygote, because of inbreeding within breeds, (F is) was between 0.089 (OarFCB304) and 0.005 (MAF33). The coefficient of genetic differentiation (F st) was between 0.100 (OarAE101) and 0.022 (OarFCB48). It indicated that 3.9% of the total genetic variation could be explained by breed differences and the remaining 96.1% by differences among individuals for each population. This illustrated that most variations existed within breeds and genetic differentiation level were very low among sheep breeds of the Mongolian Group in China. The average number of effective migrants exchanged per generation (Nem) ranged from 2.7369 (Tan sheep and Bayinbuluk sheep) to 44.3928 (Tong sheep and Hu sheep), and the mean value was 11.25213. Significantly positive relationships between the level of genetic differentiation and geographical distance and genetic distances were detected. It is concluded that genetic differentiation of sheep breeds of Mongolian group in China is mainly the result of natural selection (different living conditions). __________ Translated from Journal of Yangzhou University (Agricultural and Life Science Edition), 2007, 28(3): 22–26 [译自: 扬州大学学报(农业与生命科学版)]  相似文献   

9.
为评估连续三代减数分裂雌核发育团头鲂群体的遗传多样性和遗传纯合度,寻找区分不同团头鲂育种群体(团头鲂浦江1号选育系、连续三代减数分裂雌核发育团头鲂群体)的稳定的分子遗传标记,本研究以团头鲂(Megalobrama amblycephala)浦江1号选育系F9群体为对照组,利用39条多态性RAPD随机引物比较分析了团头鲂人工减数分裂雌核发育一代群体(G1)、二代群体(G2)和三代群体(G3)的遗传多样性和遗传结构,获得了用于鉴别不同团头鲂育种群体(F9、G1、G2、G3)的稳定的RAPD分子遗传标记,探讨了连续多代诱导减数分裂雌核发育对团头鲂基因纯化的效果。结果显示,39条RAPD随机引物在F9、G1、G2和G3群体中扩增条带总数分别为213条、202条、200条和190条,F9、G1、G2和G3群体的多态位点比例分别为36.15%、35.64%、27.00%和26.84%,F9、G1、G2和G3群体的Shannon信息指数分别为0.207 9、0.185 7、0.146 1和0.138 3。3个雌核发育群体的遗传多样性水平(多态位点比例、Shannon信息指数)均明显低于对照组F9群体,随着雌核发育世代数的增加,遗传多样性水平呈现逐代降低的趋势,即G1>G2>G3。4个群体的群体内个体间的平均遗传相似系数为0.828 5~0.906 0,3个雌核发育群体的群体内个体间平均遗传相似系数均明显高于对照组F9群体;群体内个体间的平均遗传相似系数呈现随雌核发育世代数的增加而升高的趋势,即G3>G2>G1。群体间成对FST值为0.269 2~0.419 5,经置换检验得到的FST值的P值为0.000 0~0.009 0,均达到极显著水平(P<0.01),表明4个群体间存在极显著的遗传分化。有5条随机引物在群体间产生了特异DNA片段,其中,4条随机引物(S3、S40、S58和S75)可用于区分G3群体和其他3个群体(F9、G1和G2),引物S3的鉴别可靠性最高;仅1条随机引物(S71)能用于区分G2群体和其他3个群体(F9、G1和G3)。本研究结果表明,连续多代的人工减数分裂雌核发育诱导已对团头鲂育种群体产生以下两方面的影响:一方面,遗传多样性明显降低,并呈现逐代降低的趋势;另一方面,遗传纯度明显升高,并呈现逐代升高的趋势。连续多代减数分裂雌核发育能显著加快团头鲂基因的纯合速度,雌核发育三代群体(G3)已经是一个遗传一致性较高的高纯品系。  相似文献   

10.
The pelagic larvae of many marine organisms can potentially disperse across hundreds of kilometers, but whether oceanographic or behavioral mechanisms can constrain dispersal over periods sufficient for the evolution of genetic differentiation remains unclear. Here, we concurrently examine larval duration and genetic population differentiation in a cleaner goby, Elacatinus evelynae, a member of the most species-rich genus of Caribbean reef fishes. Despite evidence for extended pelagic duration (21 days), populations of E. evelynae show strong genetic differentiation: among color forms (1.36 to 3.04% divergent at mitochondrial cytochrome b) and among island populations within color forms (Phi(ST) up to 70%). These results suggest that marine populations can remain demographically closed for thousands of generations despite extended larval duration, and that recognition cues such as color may promote speciation when geographic barriers are transient or weak.  相似文献   

11.
Selection of rootstock is very important for citrus production. Besides its major role on resistance, the rootstock also can affect fruit production and quality. Currently, the main concerns on selection of rootstock for citrus production are compatibility and resistance, due to less information on the impacts of rootstock to the performance of scion varieties. This study aims to provide information on performances of navel orange varieties on different rootstocks. Three late-ripening navel orange varieties(Citrus sinensis var. Powell, Chislett and Banfield) grafted on seven rootstocks(Swingle citrumelo(C. paradisi× P. trifoliata), Carrizo citrange(C. sinensis×P. trifoliata), X639(C. reticulata×P. trifoliata), MXT(C. sinensis×P. trifoliata), Hongju(C. reticulata), Ziyang Xiangcheng(C. junos) and trifoliate orange(P. trifoliata)) were used as plant materials for comprehensive comparison of the performances on tree growth, fruit yield and quality in 21 scion–stock combinations. Investigation was carried out in these combinations in field nine years after planting. Vigorous growth of all the three late-ripening navel orange varieties was observed on Carrizo citrange with the largest canopy volume at 33.34 m3 and the highest yield at 29.43 kg per tree, but a low yield efficiency at 2.87 kg m–3. On the contrary, those on trifoliate orange had the smallest canopy volume at 10.79 m3 and the lowest fruit yield at 12.51 kg per tree, but the highest yield efficiency at 3.95 kg m–3. Rootstocks did not show significant effects on fruit size, fruit shape index, peel thickness and the edible rate of the fruits, but fruit quality was significantly affected by the rootstocks. Fruits from the trees grafted on trifoliate orange presented the best quality with significantly higher total soluble solids(TSS) content than those on Ziyang Xiangcheng and Hongju, and also the highest ratio of TSS/titratable acidity(TA). The TA content was observed from the fruits on X639 at 0.59 g 100 mL–1. Vitamin C(Vc) content of fruits on Hongju was the highest at 49.25 mg 100 mL–1. Growth vigor of the trees was positively correlated with fruit yield at an extremely significant level. The canopy volume was negatively correlated with yield efficiency, but positively correlated with compatibility index. Results of this study indicated that the rootstock has great impacts on the growth vigor of the tree, yield efficiency and quality of the fruit. In order to achieve good quality and yield efficiency for navel orange production, less growth vigor rootstock such as trifoliate orange is highly recommended.  相似文献   

12.
中国3种不同生物型烟粉虱的种群DNA多态性研究   总被引:1,自引:1,他引:0  
利用基因组DNA的多态性研究了中国3种不同生物型烟粉虱的种群分化.烟粉虱种群分别采自北京、扬州和广州的不同寄主上,烟粉虱生物型包括B型、本地型(NaC)和一种新的生物型(Cv型).对3种生物型烟粉虱的RAPD-PCR结果进行遗传距离聚类分析,结果显示烟粉虱中国本地型和Cv型的种群关系比较近缘,二者与B型种群的亲缘关系较远.3个烟粉虱生物型的种群分化属于种内分化,据此推测Cv型烟粉虱可能起源于中国或其临近地区.  相似文献   

13.
 球孢白僵菌是一种广谱性虫生真菌,在害虫种群的自然控制中发挥着重要作用。为弄清云南省球孢白僵菌种群的遗传多样性,丰富云南虫生真菌多样性内容,本研究采用ISSR分子标记技术对云南不同地区及不同寄主来源的39个球孢白僵菌菌株的遗传多样性进行了分析。结果表明,有11个ISSRs可用于39个球孢白僵菌菌株群体PCR扩增,每个引物扩增5~15条DNA带。供试39个球孢白僵菌菌株群体的多态位点百分率(PPL)达99.09%,不同寄主来源亚种的Nei基因多样性(He)为0.3478,居群间的基因分化系数(Gst)为0.0724,总基因多样性(Ht)为0.3518,亚种群内基因多样性(Hs)为0.3263,不同寄主亚种群间的基因流(Nm)为6.4044;不同地理来源白僵菌种群Nei基因多样性指数He为0.3444,Shannon 指数I为0.5152;总基因多样性Ht为0.3473,亚种群内基因多样性Hs为0.2131,亚种群间的基因分化系数Gst为0.3862。综合遗传多样性结果,云南省球孢白僵菌种群遗传结构复杂、遗传异质性明显,从寄主来源来看,居群间遗传变异较小,居群内遗传分化较大;从地理来源来看,居群间遗传变异较大,居群内表现遗传变异较小。  相似文献   

14.
【目的】了解广东省球孢白僵菌Beauveria bassiana的群体遗传结构、基因流、菌株分化、遗传变异和寄主类型,以及与生态环境的相关性,为筛选优良生产菌株提供后备种质资源。【方法】采用SSR分子标记对广东省鼎湖山国家级自然保护区(以下简称"DHS")采集的81株球孢白僵菌进行遗传结构和多样性分析。【结果】使用8对SSR引物扩增81个菌株产生多态位点数为58个,多态位点比率为100%,其中,引物Ba12多态位点数最多(10个)。通过Popgene 32软件包分析发现,DHS球孢白僵菌种群Nei’s基因多样性指数(h)为0.212 6,Shannon信息指数(I_s)为0.348 7,可见其遗传多样性水平较高,群体异质性较强。将群体分别按照寄主和土壤、不同寄主目划分为不同亚群进一步分析,发现土壤亚群遗传多样性水平(h=0.192 5,I_s=0.309 9)略高于寄主亚群(h=0.176 9,I_s=0.278 3),种群间遗传分化程度较弱(N_m=1.662 9,G_(st)=0.130 7);不同寄主目群体间的遗传分化较小且基因流明显。基于UPGMA聚类分析发现,各分支菌株的分布趋势与分离基质、不同寄主目均没有相关性。【结论】DHS球孢白僵菌遗传谱系与分离基质和寄主来源均无明显相关性,不同生态环境和寄主类型的影响共同维持了DHS球孢白僵菌种群内遗传变异的多样性。  相似文献   

15.
Seven microsatellite loci were evaluated to compare the allele pool of Primorsky honeybee population (n = 90), which was introduced into the Novosibirsk region (south-western Siberia), with the populations of Middle Russian (n = 191, A.m. mellifera), Mountain Grey Caucasian (n =113, A.m. caucasica), Carniolan (n = 61, A.m. carnica) and Carpathian (n = 184, A.m. carpatica) races. The degree of genetic differentiation in Novosibirsk population using a variety of criteria (Fst, Rst (AMOVA), Nei genetic distances) was evaluated.  相似文献   

16.
中国蒙系6个绵羊品种的遗传分化和基因流   总被引:1,自引:2,他引:1  
利用7对微卫星引物对中国蒙系6个绵羊品种(同羊、小尾寒羊、湖羊、滩羊、乌珠穆沁羊和巴音布鲁克羊)的遗传分化、基因流、遗传分化程度与地理距离间的关系进行分析,并利用遗传距离构建系统树。结果表明:6个绵羊群体中,总群体近交系数Fit最高的位点为OarAE101(0.1670),最低的为MAF33(0.0440);群体间分化系数Fst最高的位点为OarAE101(0.1000),最低的为OarFCB48(0.0220);群体内近交系数Fis最高的位点为OarFCB304(0.0890),最低的为MAF33(0.0050)。Fst平均为3.9%,即由各群体内个体间的差异引起的遗传变异是96.1%,说明遗传变异绝大部分存在于品种内,品种间的遗传分化水平很低。6个绵羊群体每世代两群体间有效迁移个体数为2.7369(滩羊和巴音布鲁克羊)~44.3928(同羊和湖羊),平均为11.2521,均反映出品种间的基因流通畅。品种间的遗传差异与地理距离呈显著相关。初步推断我国蒙系绵羊品种间的遗传分化主要是自然选择(生境异质性)作用的结果。  相似文献   

17.
[目的]了解广西桂林Barnfield脐橙花芽分化的形态过程,调控脐橙花芽分化,为提高广西脐橙的果实产量和品质提供理论依据.[方法]用改良的FAA固定脐橙花芽,海氏苏木精整体染色,常规石蜡切片解剖,显微镜观察花芽分化的过程.[结果]Barnfield脐橙花芽大都在12月初进行花原基分化,高峰期集中在12月中下旬至次年1月上旬.12月中旬开始出现萼片原基,盛期在次年1月中下旬;次年1月中旬出现花瓣原基,中下旬进行雄蕊原基分化,高峰期在2月中下旬.[结论]在广西桂林地区环境条件下,Barnfield脐橙花芽分化期大致在12月至次年3月,分化进程存在前期较慢,后期较快的特点.  相似文献   

18.
长圆形纽荷尔脐橙变异株植物学特性描述及RAPD分析鉴定   总被引:1,自引:1,他引:0  
通过6 a鉴选,长圆形纽荷尔脐橙变异株与纽荷尔脐橙相比,植株形态、叶、花、产量和综合品质差异不明显;但果实外观却有明显差异,变异株果实呈长圆形,果形指数比纽荷尔脐橙大,果实颜色较深,为橙红色。通过RAPD分析鉴定,得到变异株和纽荷尔脐橙的遗传距离为0.005 5,差异较小。  相似文献   

19.
针对脐橙自动分级检测中存在正确识别率偏低、实时性不强的问题,提出一种综合特征提取方法:在对图像颜色模型进行转换后,用H分量图像提取脐橙的大小特征;S分量图像通过背景分割、边缘灰度补偿、整体亮度变换后提取脐橙的果面缺陷特征;采用R、G、R-G3个分量的均值和标准差提取脐橙的颜色特征。以脐橙的大小特征、果面缺陷特征和颜色特征为支持向量机(Support vector machine,SVM)的试验输入向量,进行脐橙分级检测试验,以实现提高脐橙自动分级正确识别率和增强实时。试验结果表明:该SVM分类器对脐橙分级的正确识别率为91.5%,处理时间为160ms,适合于实时环境下的分级检测。  相似文献   

20.
采用PCR扩增结合DNA克隆测序技术,分析了斑翅草螽Conocephalus maculates 9个地理种群mtDNA控制区序列的变异及遗传多样性.切除侧翼RNA基因序列后,最终获得的斑翅草螽mtDNA控制区比对后全长为676 bp,平均碱基组成T(37.8%),C(11.7%),A(41.3%)和G(9.1%).共检测到98个可变位点,占总位点数的14.5%,其中,9处碱基插入/缺失,74处转换(40个T/C,34个A/G),50处颠换(18个A/T,11个T/G,15个A/C,6个C/G).共定义46个单倍型,其中,4个为种群间共享单倍型(H02、H05、H08和H10),其余42个为各种群独有单倍型,包括6个种群内共享单倍型(H09、H11、H15、H18、H26和H38).单倍型总数占实验个体总数的69.7%,除四川峨眉山外,其余种群单倍型百分比均>50%.通过两两地理种群间的FST值差异显著性检验,将这些群体分为4组,分别为SC+CQ,GX+FLB+HN+YN,XZ和HB.以长瓣草螽C.gladiatus、峨眉草螽C.emeiensis、悦鸣草螽C.melaenus、竹草螽C.bambusanus为外群,构建的斑翅草螽mtDNA控制区单倍型NJ法系统树形成3个自举支持度较高的分支,其中,分支A由28种单倍体组成,包括本研究中除四川峨眉山(SC)和重庆万州(CQ)以外的7个种群;分支B由12种单倍体组成,包含除菲律宾拉乌尼翁(FLB)和江西南昌(JX)以外的7个种群;分支C由6种单倍型组成,全部来自西藏林芝(XZ)的单倍型.聚类结果表明,斑翅草螽不同地理种群间的遗传分化并不明显,即使是两两群体间FST值差异显著的群体,也未能形成完全独立的分支.  相似文献   

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