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71.
通过分析青天葵及其常见混伪品的ITS2序列,建立青天葵新型真伪鉴别方法.采用植物基因组DNA提取试剂盒提取青天葵及其混伪品的叶片DNA,一对通用引物PCR扩增ITS2基因片段并直接双向测序.采用DNAMAN、ClustalX软件拼接比对序列,MEGA4.0软件构建NJ树,Schultz等建立的数据库和网站预测ITS2序列的二级结构.结果显示,获得的12条ITS2序列的长度范围为203-242 bp,GC含量范围为53.1%-71.8%.所有样品ITS2序列比对后的长度为249 bp,其中存在226个变异位点.青天葵种间K2P遗传距离(1.125)远大于种内K2P遗传距离(0.004).基于ITS2的序列的NJ树和二级结构均能直观地区分青天葵及其混伪品. 相似文献
72.
Prakash Y. S.; Gosselin L. E.; Zhan W. Z.; Sieck G. C. 《Journal of applied physiology》1996,81(3):1240-1248
73.
番茄五个品种的核型研究(摘要) 总被引:1,自引:0,他引:1
本文研究了番茄五个不同品种(武昌大红、加拿大、佛特、荷兰五号、青北早)的核型。1.番茄的核型公式如下: (1) 武昌大红。2n=24=2M+8m+12sm+2st (2) 加拿大。2n=24=4M+8m+12sm (3) 佛特。2n=24=2M+8m+10sm+4st (4) 荷兰五号2n=24=2M+14m+8sm (5) 青北早2n=24=4M+8m+12sm 2、五个品种中都具有一对随体染色体,但位于那一对染色体上也有相同和相异。“武昌大红”与“佛特”的随体在第9对上。“加拿大”在第7对上。“荷兰五号”及“青北早”位于第4对染色体上,并发现“武昌大红”、“加拿大”品种的随体,在同一品种也出现随体大小的差异。3、在各个品种中,染色体的全长、相对长度、臂比都存在着一些差异。4、对于番茄染色体的随体的大小及其在染色体对数的位置,染色体的形态结构,核形与番茄起源的关系进行了初步讨论。 相似文献
74.
75.
Xin Zhan Hai-Yan Hu Cai-Huan Ke Song-Nian Hu De-Xiang Wang Fei Chen 《Conservation Genetics》2009,10(4):1185-1187
Eleven novel microsatellite markers were isolated from small abalone, Haliotis diversicolor Reeve. These loci were tested on 22 individuals from two different geographic populations. We identified a total of 162 alleles
from the 11 microsatellite loci. All of the loci were highly polymorphic. Polymorphism information content (PIC) is ranging
from 0.7276 to 0.9163. Observed and expected heterozygosities ranged from 0.2727 to 1.0000 and from 0.7738 to 0.9429, respectively.
Three loci deviated significantly from Hardy–Weinberg equilibrium. No pairs of loci displayed linkage disequilibrium. These
polymorphic markers will be used to analyze population structure, genetic diversity and construct a genetic linkage map.
Xin Zhan and Hai-Yan Hu contribute equally to this study. 相似文献
76.
本研究中用融合标签技术通过单质粒转化和双质粒转化分别促进Aβ1-42淀粉样蛋白的可溶性表达.构建重组载体pET(yd-b42)、pET(Msb-b42)、pET(Od-b42)、pAY-sls[ydb42]、pAY-sls[tydb42],并在大肠杆菌中表达,通过SDS-PAGE验证分析.标签yd、Msb、Od、tyd都能很好的促进ABβ1-42淀粉样蛋白可溶性表达,其中yd、tyd的促溶效果最好.Aβ1-42淀粉样蛋白能在大肠杆菌中可溶性表达.为阿尔茨海默病的治疗提供进一步理论基础. 相似文献
77.
78.
He Liming Xu Yungang Zeng Fansuo Tian Hongmei Xiao Ying Liu Hualing Yu Lei Zhan Yaguang 《In vitro cellular & developmental biology. Plant》2021,57(2):307-318
In Vitro Cellular & Developmental Biology - Plant - The interspecific hybridization can take advantage of heterosis and combine the double parental traits most extensively, and is an effective... 相似文献
79.
Liu HT Huang WD Pan QH Weng FH Zhan JC Liu Y Wan SB Liu YY 《Journal of plant physiology》2006,163(4):405-416
The relationship between the accumulation in endogenous free salicylic acid (SA) induced by heat acclimation (37 degrees C) and the activity of PIP(2)-phospholipase C (PIP(2)-PLC; EC 3.1.4.3) in the plasma membrane fraction was investigated in pea (Pisum sativum L.) leaves. We focused our attention on the hypothesis that positive SA signals induced by heat acclimation may be relayed by PIP(2)-PLC. Heat acclimation induced an abrupt elevation of free SA preceding the activation of PLC toward PIP(2). Immunoblotting indicated a molecular mass with 66.5kDa PLC plays key role in the development of thermotolerance in pea leaves. In addition, some characterizations of PLC toward PIP(2) isolated from pea leaves with two-phase purification containing calcium concentration, pH and a protein concentration were also studied. Neomycin sulfate, a well-known PIP(2)-PLC inhibitor, was employed to access the involvement of PIP(2)-PLC in the acquisition of heat acclimation induced-thermotolerance. We were able to identify a PIP(2)-PLC, which was similar to a conventional PIP(2)-PLC in higher plants, from pea leaves suggesting that PIP(2)-PLC was involved in the signal pathway that leads to the acquisition of heat acclimation induced-thermotolerance. On the basis of these results, we conclude that the involvement of free SA may function as the upstream event in the stimulation of PIP(2)-PLC in response to heat acclimation treatment. 相似文献
80.
Yang Jiang Lin Ling Lingli Zhang Abigail Domingo Mingli Cai Chengfang Li Ming Zhan Jinping Wang Cougui Cao 《Acta Physiologiae Plantarum》2017,39(3):89
Transgenic Bacillus thuringiensis (Bt) rice have been reported to acquire effective resistance against the target pests; however, the insertion and expression of alien Bt genes may have some unintended effects on the growth characteristics of rice. A screen-house experiment was conducted and repeated twice to investigate the growth characteristics and Bt protein expressions in two Bt rice lines [MH63 (Cry2A*) and MH63 (Cry1Ab/Ac)], which had different Bt protein expression levels in leaves, under zero nitrogen (N0) and recommended nitrogen (NR) fertilizer applications. Compared to the counterpart MH63, MH63 (Cry2A*) under N0 experienced accelerated leaf senescence and a lower internal N use efficiency (IEN), resulting in a 23.2% decrease in grain yield and a lower accumulated biomass. These variations were revealed to be correlated to the higher ratio of the Bt protein content to the soluble protein content (BTC/SPC) with a maximum value of 4.3‰ in MH63 (Cry2A*) leaves in the late growth stage. Under NR, no differences in growth characteristics between MH63 (Cry2A*) and MH63 were found. The growth characteristics of MH63 (Cry1Ab/Ac), with a lower BTC/SPC in the late growth stage compared to MH63 (Cry2A*), were identical to those of MH63 under the two N applications. Results show that the transgenic Bt rice MH63 (Cry2A*), with a relatively higher Bt protein expression in the late growth stage, had an inferior adaptation to nitrogen deficiency compared to its non-Bt counterpart. And this inferior adaptation was found to be correlated with the higher BTC/SPC in MH63 (Cry2A*) leaves in the late growth stage. 相似文献