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141.
芫花乙醇粗提物经石油醚及氯仿萃取,萃取物经柱层析、薄层层析和生测后分别获得较纯组分.以这两种组分进行结构鉴定及返回生物测定(试虫卫矛尺蠖Abraxesmiranda),结果证明,β-谷甾醇是芫花中具有强烈拒食活性的组分之一.这两个组分中均有雪松醇,其杀虫活性有待于进一步研究证实. 相似文献
142.
本文根据2001和2002年的调查结果,记述了广东省东莞莲花山自然保护区的昆虫种类调查结果.共计11目69科193种。 相似文献
143.
桑树杂交组合桂桑优12的育成 总被引:3,自引:1,他引:2
应用遗传互补和杂种优势原理 ,育成桑树新品种 (杂交组合 )桂桑优 12。其F1群体整齐、发条数多、枝高节密、叶大叶厚、耐剪伐、再生能力强、发芽较早、收造较晚、产叶量较高、叶质较优、繁育较易 ,适宜常规栽培以及加速生丰产和省力化养蚕栽培。与对照沙 2×伦 10 9相比 ,每公顷桑叶产量增产 11 36 % ,桑叶养蚕万头蚕产茧层量增加 4 4 2 % ,10 0kg桑叶产茧量增产 3 18% ,每公顷桑园产茧量增产 19 6 3%。 相似文献
144.
利用8个微卫星标记对杜长大三元杂交群体5个种群,斯格配套系8个种群的遗传结构进行了分析。通过计算等位基因频率、基因杂合度、平均杂合度、多态信息含量、纯种间的遗传距离、F-统计量和迁移率进行分析。结果表明各群体的平均基因杂合度存在一定差异。纯种、祖代、父母代、商品代群体的平均座位杂合度和多态信息含量随着群体在杂交繁育体系中位置的由高到低而逐渐升高。Nei氏标准遗传距离显示,父本和母本间的遗传距离大,遗传距离大的父本和母本用于杂交,产生的杂种优势最大,这与实际的杂交组合一致。Fst衡量等位基因频率群体间方差,杜长大群体大约总变异的1.02%~15.60%来自种群间,而剩余的84.40%~98.98%来自种群内,斯格群体大约总变异的3.02%~15.22%来自种群间,而剩余的84.78%~96.98%来自种群内,斯格和杜长大纯种的遗传分化处于较小到中等之间。 相似文献
145.
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147.
MO Jiayuan GAO Jiuyu FENG Lingli LI Yueyue TIAN Weilong LIU Xiaoxiao CHENG Feng LIANG Liang LEI Shuqiao WEN Wei LIANG Jing LAN Ganqiu 《中国畜牧兽医》2007,47(12):3965-3975
In order to identify the molecular markers related to alive litter size of Bama Xiang pigs,the genome-wide association study (GWAS) was used to map and screen the candidate genes affecting the alive litter size trait.Ear tissue samples of 297 Bama Xiang pigs with multiple parity records were collected,and DNA was extracted and genotyped by porcine 50K SNP beadchip.After quality control and genotype imputation,the alive litter size of Bama Xiang pigs were GWAS by Tassel.The results showed that the average number born alive per litter of Bama Xiang pigs increased gradually with the increasing of parity in the range of 1-9 parities.A total of 32 816 SNPs were obtained after quality control and filtration.8 SNPs related to alive litter size of Bama Xiang pigs were screened by genome-wide association analysis,which were significant at genome or chromosome level.Based on the enrichment analysis of the coding genes in the region between 500 kb upstream and downstream of the associated significant SNP loci,and the QTL regions and gene functions related to porcine reproductive traits,4 genes (CAPZB,MSH3,CITED2 and HSD17B7) were finally identified to be candidate genes related to alive litter size of Bama Xiang pigs. 相似文献
148.
XIONG Xiaoyan QIN Zhenbin MO Hongfang HE Dongxian YU Lintian XU Jiarong 《中国畜牧兽医》2007,47(12):4032-4040
This study was designed to evaluate the synergistic effect of VA5 immunopotentiator on pigeon ND4416 inactivated vaccine.160 healthy pigeons were randomly divided into four groups,including ND4416 strain inactivated vaccine group (NDV group),ND4416 strain inactivated vaccine and immunopotentiator (VA5) mixed group (NDV+VA5 group),La Sota inactivated vaccine group (La Sota group) and normal saline as the control group (C group),to assess their vaccine efficacy against virulent pigeon NDV by serological analysis and animal testing.Pigeons sera were collected at different time points after immunization and measured the HI antibody titer of each group.The results showed that VA5 immunopotentiator significantly improved the serum antibody level of pigeons immunized with pigeon Newcastle disease inactivated vaccine (P<0.05).In addition,comparative test of spleen lymphocyte transformation was conducted at various time points after immunization.The results indicated that VA5 effectively stimulated the lymphocyte transformation of immune pigeon.Pigeons in each groups were challenged with ND4416 strain at the 30th,90th and 180th d after immunization.The results presented that the NDV+VA5 group had 100% protection rate and higher than La Sota group.The duration of immunization test showed that the antibody titer of NDV+VA5 group reached peak 11.20log2 at the 21st d,remained 7.50log2 at 180th d,and the protection rate remained 100% at 180th d.It indicated that VA5 immunopotentiator sustained the immune duration of pigeon NDV vaccine up to 180 d.Moreover,the in vitro detoxification test results suggested that VA5 immunopotentiator reduced the in vitro detoxification cycle of pigeons after challenge.Overall,this study suggested VA5 immunopotentiator could significantly improve the immune efficacy of pigeon Newcastle disease inactivated vaccine,which provided a basis for further enhancing the efficacy of Newcastle disease vaccine,as well increased experimental data for the application of immunopotentiators. 相似文献
149.
云南、福建、湖南烟区烟草花叶病主要病毒种类检测及黄瓜花叶病毒亚组鉴定 总被引:10,自引:0,他引:10
采用抗原直接包被和双抗体夹心酶联免疫吸附测定法(ELISA)对采自云南、福建、湖南烟区烟草花叶病样品进行了病毒种类检测,利用三抗体夹心ELISA对黄瓜花叶病毒(Cucumber mosaic virus,CMV)的亚组类型进行了鉴定。在云南采集的520个花叶病样品中,烟草花叶病毒(Tobacco mosaic virus,TMV)、CMV和马铃薯Y病毒(Potato virus Y,PVY)总检出率分别为71.74%、55.01%和6.35%;在福建采集的150个花叶病样品中,TMV、CMV和PVY的总检出率分别为94%、24.66%和8.00%;在湖南采集的74个花叶病样品中,TMV、CMV和PVY的总检出率分别为58.11%、51.35%和2.70%。部分样品为2种以上病毒复合侵染。云南、福建和湖南采集的64个CMV阳性样品中,属亚组Ⅰ的样品为57个,占89.1%;属亚组Ⅱ的样品为10个,占15.6%;其中3个样品为亚组Ⅰ和亚组Ⅱ的复合侵染。 相似文献
150.