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991.
992.
993.
杨小舟蛾发生规律与测报技术研究 总被引:12,自引:1,他引:11
杨上舟蛾[Micromelalopha troglodyta(Graeser)]中关中1年发生5代,以7、8月份的3、4代种群数量最大,危害最重。其天敌种类较多,多一年内种群数量消长影响较大,5~8月份降雨较多的年份发生较重。介绍了发育进度预测法,种群消长趋势指数预测法和黑光洒诱测法在杨小舟蛾测报中的应用。 相似文献
994.
Mercedes Fernandez-Moreno Alberto Arias-Perez Ruth Freire & Josefina Méndez 《Aquaculture Research》2008,39(5):474-481
Aequipecten opercularis (Queen scallop) and Mimachlamys (Chlamys) varia (Black scallop) are important natural resources occurring in Atlantic and Mediterranean coasts. To develop an optimal sustainable exploitation plan, it is important to study the genetic structure of the different populations. In this study, we used polymerase chain reaction‐restriction fragment length polymorphisms for the determination of the genetic variation and population structure of these two species in different localities. Ten composite haplotypes were generated for A. opercularis and 15 haplotypes for M. varia. Of these, six and four were unique respectively. The analysis of the distribution of the different haplotypes between the localities showed no clear evidence of subdivision in A. opercularis, while in M. varia the results indicated that the two localities analysed should be managed as separate stocks. 相似文献
995.
Most often a genetic linkage map is prepared using populations obtained from two highly diverse genotypes.However the markers from such a map may not be useful in a breeding program as these markers may not be polymorphie among the varieties used in breeding.…… 《分子植物育种》2007,5(2):219-220
Most often a genetic linkage map is prepared using populations obtained from two highly diverse genotypes. However, the markers from such a map may not be useful in a breeding program as these markers may not be polymorphic among the varieties used in breeding. For the past nine years, intraspecific maps have been gaining importance and such maps based on Swiss (PaiUard et al., 2003), Japanese (Suenaga et al., 2005), Australian (Chaimcrs et al., 2001) wheat varieties arc available. A map based on Indian wheat varieties however has not been reported. We constructed a genetic linkage map based on a cross between two Indian bread wheat (Triticum aestivum L.) varieties, Sonalika and Kalyansona. One hundred and fifty F2 individuals were analyzed for arbitrarilyprimed polymerase Chain reaction (AP-PCR), random amplified polymorphic DNA (RAPD), inter simple sequence repeats (ISSR), Sequence Tagged Microsatelhte Sites (STMS), Amplified Fragment Length Polymorphism (AFLP) markers, seed storage proteins and known genes. A linkage map was constructed consisting of 236 markers and spanning a distance of 3 639 cM with 1 211.2 cM for A genome, 1 669.2 cM for B genome, 192.4 cM for D genome and 566.2 cM for unassigned groups, 相似文献
996.
997.
吉林省耕地压力指数时空分异特征研究及其预测研究 总被引:1,自引:0,他引:1
笔者运用耕地压力指数模型和灰色系统理论GM(1,1)模型,对吉林省2003—2012 年间的耕地利用压力指数时空分异特征进行分析,并对其动态变化和未来发展趋势进行了预测。研究结果显示:随着时间的推移,加之国家放开“二胎政策”人口不断在增加,未来人口会出现增加趋势,即使在规定未来十年内人们的人均食物需求量也会不增加的基础上,最小人均耕地面积的增加幅度越来越小,以及大量耕地向建设用地转换,使得耕地压力指数有过大的趋向,而且2017—2027 年吉林省的耕地压力指数处于上升的趋向,即使耕地压力不是很明显,但仍不可忽视。过大的趋向,而且2017-2027年吉林省的耕地压力指数处于上升的趋向,即使耕地压力不是很明显,但仍不可忽视。 相似文献
998.
【目的】探索饲喂细菌表达目标基因dsRNA介导桔小实蝇flightin基因RNAi的可行性。【方法】将桔小实蝇flightin基因的相应干扰片段构建至L4440干扰载体,并转化大肠杆菌HT115(DE3)菌株,利用IPTG诱导表达flightin基因对应的dsRNA,命名为flightin-dsRNA。【结果】通过饲喂表达flightin-dsRNA的大肠杆菌10倍浓缩菌液,桔小实蝇flightin基因的表达普遍出现了不同程度的上调,其中,雌虫饲喂后5、10、20 d,雄虫饲喂后5 d与对照差异显著,雄虫饲喂后15 d诱发约43%的下调;该方法对桔小实蝇飞行能力及胸部肌肉发育未产生明显影响。【结论】通过饲喂表达flightin-dsRNA的大肠杆菌对桔小实蝇flightin基因进行RNA干扰不可行或干扰效果不明显。 相似文献
999.
Laddawan Krongpong Kunihiko Futami Takayuki Katagiri Makoto Endo Masashi Maita 《Fisheries Science》2008,74(5):1055-1061
Furazolidone, an antibacterial drug that was once widely used in the livestock industry and aquaculture, is now prohibited
in numerous countries. It is difficult to detect residual furazolidone because it is readily metabolized in animal tissues
but, by using and liquid chromatography coupled with tandem mass spectrometry, its metabolite, 3-amino-2-oxazolidinone (AOZ)
can be detected. Here we describe the validity of an enzyme-linked immunosorbent assay (ELISA) kit to detect AOZ in Japanese
eel Anguilla japonica tissue. ELISA is capable of detecting AOZ at 1.0 μg/kg in an eel sample with excellent accuracy and precision. Our results
show that ELISA is suitable for regulatory purposes and for studying the fate of AOZ residues in eel treated with furazolidone.
To measure the persistence of AOZ in eel tissues, eels (1.4–6.5g) were immersed in tanks containing 2 and 10 mg furazolidone/L
for 3 h, and then maintained in a tank supplying well water for the next 160 days. The half-lives of AOZ, calculated from
the linear terminal part of the excretion curve, were 25.0 days in muscle and 21.6 days in liver from fish exposed to 2 mg/L
furazolidone. In the eels treated with 10 mg/L furazolidone, by contrast, high levels of AOZ were detected in liver and muscle,
but the half-lives of AOZ were similar to those in fish treated with 2 mg/L furazolidone. The half-lives of AOZ in eel tissues
were prolonged by the condition of low water temperature. 相似文献
1000.
凡纳滨对虾6个养殖群体遗传多样性的比较分析 总被引:4,自引:1,他引:3
中国多批次引进凡纳滨对虾Litopenaeus vannamei并结合生产开展了相对独立的育苗工作,但对引进群体及引进后留种形成的本地群体的遗传变异水平缺乏了解,不利于种质管理及利用。此研究采用AFLP技术对抽查的6个养殖群体进行分析,发现进口群体具有相对较高的遗传多样性水平;养殖性能较好的东方、海星和旭明群体遗传多样性水平与进口群体相近;而乾塘群体遗传变异水平最高,推测可能是与其种质混杂有关;广益群体遗传多样性水平最低,可能已出现近交衰退。通过对各个群体间的遗传距离进行分析,为下一步根据亲缘关系的远近开展群体问杂交育种提供技术依据。 相似文献