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121.
GA1,3,4,7酶联免疫检测法(ELISA)的建立 总被引:11,自引:1,他引:11
用碳二亚胺法将赤霉素A4与卵清蛋白连接,形成GA4-OVA复合物用于包板,利用GA4-Me与GA4-0VA对兔抗GA4-PAbs竞争结合反应,建立了GA1,3,4,7间接酶闻免疫检测法。其灵敏度,检测范围和最小检测样品量分别为45pg,0.2-200ng和50-500mg,样品的平均回收率为97%,批内和批间的变异系数分别为4.2%和4.8%。 相似文献
122.
P. Monneveux M. P. Reynolds J. González Aguilar R. P. Singh W. E. Weber 《Plant Breeding》2003,122(5):379-384
The 7DL.7Ag translocation from Lophopyrum elongatum that carries Lr19, a leaf rust resistance gene, was found to be associated with a significant increase in grain yield under irrigated, disease‐free conditions, but a generally lower yield under moisture stress conditions. These studies, however, involved a limited number of genetic recipients and environments, and the effect of the translocation on physiological traits was not considered. We examined the translocation effect in six different recipient genotypes and under five environmental conditions, including drought and heat stress. The increase in grain yield under irrigated conditions was associated with a higher rate of biomass production in the 7DL.7Ag lines and may be attributed to higher sink strength. Effect of the translocation on physiological traits was noted only under heat stress and was not associated with difference in yield. Under moisture stress conditions, 7DL.7Ag lines yielded less than their corresponding recipients, possibly because of a longer growing cycle. It is concluded that the effect of the 7DL. 7Ag translocation may very much depend on the phenological adaptation of the recipient genotype and the translocation may be useful for enhancing yield, mainly under favourable conditions. 相似文献
123.
夏播大豆品种的生育期特性与农艺性状的关系分析 总被引:2,自引:0,他引:2
从 339个大豆品种中选取生育期小于 1 0 0d的 1 0 3个品种进行生育期结构特性与农艺性状的分析。结果表明 :①R1最长的为华北品种 ,最短的为外国品种 ;②R7最长的为东北品种 ,最短的为南方品种 ;③R1与生育前期即营养生长阶段 ,高纬地区长于低纬地区 ;R7与生育后期即生殖生长阶段 ,低纬地区长于高纬地区 ;④R1、生育前期长的品种 ,单株荚数、单株粒数多 ,株高较高 ;R7、生育后期长的品种 ,百粒重高 ;⑤筛选出一批对光温不敏感的品种 相似文献
124.
The present study was aimed to investigate the possible interaction of the standardized extract of Acorus calamus (AC) with Cytochrome P450 enzyme, quantitative determination of the α-asarone in the AC rhizome was performed by RP-HPLC method. In vitro interaction of the plant extract was evaluated by CYP450-carbon monoxide complex (CYP450-CO) assay. Effect on individual isoforms such as CYP3A4 and CYP2D6 isozymes were analyzed through fluorescence product formation and respective IC50 values were determined. CYP450-CO assay showed moderate interaction potential. Extract showed higher IC50 values (46.84 ± 1.83-32.99 ± 2.21 μg/ml) comparing to the standard inhibitors and lower IC50 value than α-asarone (65.16 ± 2.37-42.15 ± 2.45 μg/ml). 相似文献
125.
Elena Valkama Minna Kivimenp Helin Hartikainen Anu Wulff 《Agricultural and Forest Meteorology》2003,120(1-4):267
The possible ameliorative effects of selenium (Se) addition to soil on the detrimental effects of enhanced UV-B radiation were tested on strawberry and barley during 4 months of field experiment in Kuopio, Central Finland. Control plants were exposed to ambient levels of UV radiation, using arrays of unenergized lamps. A control for UV-A radiation was also included in the experiment. Added Se, applied as H2SeO4, at the level of 0.1 mg kg−1 soil (low dosage) and 1 mg kg−1 soil (high dosage) increased Se concentrations in plants more than 10 and 100 times, respectively. After 4 months of exposure, strawberry and barley plants were harvested for biomass analysis. Chlorophyll fluorescence was measured using the Hansatech FMS2 fluorescence monitoring system. Leaf anatomy and ultrastructure were observed by light and transmission electron microscope. Several effects of UV and Se as well as their interaction were found, mostly for strawberry, but not for barley, indicating species-specific responses. Our results provided evidence that the high Se concentration in soil had no ameliorative effect but increased the sensitivity of strawberry to enhanced UV-B radiation in the field. Under ambient radiation, Se did not alter leaf growth of strawberry, whereas under UV-B radiation, the high Se addition significantly decreased leaf growth. Strawberry runner biomass was affected by the interaction of Se and UV. Under ambient radiation Se did not change dry weight of runners, but in combination with UV-A or UV-B radiation the high Se dosage decreased dry weight of runners by about 30%. Although the high Se concentration positively influenced on quantum efficiency of photosystem II (PSII) in strawberry leaves, it reduced runner biomass, leaf number and ratio of starch to chloroplast area. This suggests that the harmful effects of the high Se dosage on photosynthetic processes occurred as a result of changes in activity or/and biosynthesis of enzymes, rather than alteration of PSII. At the low concentration, Se effects were slight and variable.Although barley leaves accumulated higher Se concentrations than strawberry, there were no apparent changes in their growth, biomass or chlorophyll fluorescence due to Se effect either alone or in combination with UV-B. However, at the ultrastructural level, an enlargement in the peroxisome area was found due to combination of UV radiation with Se, suggesting the activation of antioxidative enzymes, possibly catalase. Decrease in mitochondrial density in barley cells in response to Se might be attributed to alteration of mitochondrial division. Increase in the proportion of cells with cytoplasmic lipid bodies due to combined effect of UV-B and Se indicated the alteration of lipid metabolism and the acceleration of cell senescence in barley. Main UV-B effects were found, mostly at the tissue and ultrastructural level in strawberry, but not in barley, indicating species-specific susceptibility to enhanced UV-B radiation. UV-B-treated strawberry plants developed marginally thinner leaves with reduced ratio of starch to chloroplast area in their cells, suggesting negative influence of UV-B on photosynthetic processes. 相似文献
126.
龙岩7—3自育成以来,至今还在全国各地大面积推广应用,表现出高产、稳产、适应性广和商品性好等特点。该品种在福建连城县甘薯种植1万多公顷中占80%,是龙岩连城县地瓜干最主要的原材料来源。文中介绍了其选育、特征特性及加工利用。 相似文献
127.
Diana Stuart 《Agriculture and Human Values》2008,25(2):177-181
I explore the role of nature in the agrifood system and how attempts to fit food production into a large-scale manufacturing
model has lead to widespread outbreaks of food borne illness. I illustrate how industrial processing of leafy greens is related
to the outbreak of E. coli 0157:H7 associated with spinach in the fall of 2006. I also use this example to show how industry attempts to create the
illusion of control while failing to address weaknesses in current processing systems. The leafy greens industry has focused
efforts on sterilizing the growing environment and adopting new technologies, while neglecting to change the concentrated
structure of processing systems. Repeated breakdowns in these systems illustrate a widening fault line between attempted and
failed control of nature in industrial food production.
相似文献
Diana StuartEmail: |
128.
新疆陆地棉胚状体发生高效再生体系的建立 总被引:4,自引:0,他引:4
对新疆两个陆地棉品种胚状体发生及植株再生研究的结果表明:胚状体发生、萌发、成苗各阶段,品种问存在明显差异。新陆早1号、新陆早7号正常植株率最高分别达657%,85.7%。在胚状体发生、发育不同阶段,激素的调控作用因品种而异。异常胚是转化为正常再生植株的有效途径,异胚转化率可达47.7%。移栽基质研究表明,移栽前期选用拉卡粒,中后期转入混合土:珍珠岩=1:1的移栽基质中再生植株生长最好,再生植株移栽成活率达81.0%。建立了两个品种的胚状体发生高效再生体系。 相似文献
129.
本研究以大豆种子7S球蛋白变异系统的含硫氨基酸含量提高效果为目的,对41个7S球蛋白变异系统的氨基酸、蛋白质含量进行分析。结果在41个7S球蛋白变异系统中有、13个系统的含硫氨基酸含量超过了联合国粮农组织制定的标准,占7S球蛋自变异系统的31.7%。平均数显著性测验结果,7S球蛋白变异系统的含硫氨基酸、蛋氨酸、就氨酸含量都极显著高于正常品系,而其蛋白质含量没有显著差异。相关分析结果,7S球蛋白变异系统的蛋氨酸与优氨酸含量间,蛋氨酸及胱氨酸与含硫氨基酸含量间均为极显著正相关;蛋氨酸含量与蛋白质含量间呈显著负相关;胱氨酸及台硫氨基酸含量与蛋白质含量间无显著相关。 相似文献
130.
为了探讨小干涉RNA(siRNA)对靶基因Smad7mRNA表达的阻断作用,采用体外转录方法制备Smad7基因的小干涉RNAs(siRNAs),用脂质体介导瞬时转染BERP35T 2肺癌细胞系,并采用Northernblot杂交检测靶基因mRNA的表达丰度。结果表明,根据Smad7编码区序列在体外成功地制备了针对2个不同靶序列的siRNAs;Northernblot杂交显示,在转染siRNA的BERP35T 2细胞中,不管是内源性的还是外源性的,Smad7mRNA的表达丰度均明显下降。说明Smad7基因编码区中542563bp及701722bp2个区域均是siRNA作用的有效靶序列,本研究设计并制备的siRNAs能有效抑制Smad7基因的表达。 相似文献