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111.
胡萝卜悬浮培养细胞和原生质体的玻璃化法超低温保存   总被引:7,自引:1,他引:6  
采用玻璃化法成功地超低温保存了胡萝卡悬浮培养细胞及其原生质体,存活率分别为83.3%(TTC法检测)和47%(RDA法检测)。冻后细胞能恢复生长并再生植株。分析了玻璃化法超低温保存植物悬培养浮细胞和原生质体的主要影响因素。  相似文献   
112.
本文对大籽蒿、野艾、椒蒿的营养器官进行了组织形态学的观察.分析了药用植物的解剖学特征与药用成份的贮藏、运输和分泌的关系.并总结出这三种植物的茎与叶的显微结构特征可做为鉴别不同种和药材真伪的依据.  相似文献   
113.
The atrazine-resistant psbA gene of black nightshade was transferred to the chloroplast genome of atrazine-susceptible soybean by means of ovary microinjection during the stage of zygote. The identification was carried out by using the methods of spraying the leaves directly with atrazine solution, examining the change of leaf fluorescence kinetics under a brighter light induction, molecular hybridization, etc. The experimental results show that the transgenic soybean plants do have been obtained for the first time.  相似文献   
114.
Disposal of untreated industrial effluents is drastically deteriorating the quality of underground water. Research work has been conducted to analyze the effect of disposal of urea plant effluent on the quality of ground water of the District Mianwali Daudkhail, Pakistan. For this purpose the effluent and ground water samples were analyzed for pH, TDS, TSS, Cl, F, COD, BOD, Fe, Zn, Pb, Cu, Cr, Cd, Mn, and As. Results obtained were compared with WHO and NEQS standards for drinking and effluent emission limits, respectively. Moreover, effluent samples were also evaluated for irrigation purposes and results compared with criteria recommended for irrigation water. Results showed though the effluents were according to the standards given by National Environmental Quality Standards (NEQS) for liquid emission and fit for irrigation purposes, the quality of underground water was below standard due to having a higher quantity of total dissolved solids than permissible.  相似文献   
115.
壳聚糖抗庭院植物病原真菌的活性   总被引:1,自引:1,他引:0  
分别用过氧化氢和溶菌酶降解壳聚糖,制备得到了系列分子量(3.8×105,7.8×104,4.8×104,1.7×104,2.3×103)的壳聚糖样品.采用平板法研究了壳聚糖系列样品对大叶黄杨炭疽病、沿阶草炭疽病、广玉兰炭疽病和对节白蜡腐烂病等庭院植物病原真菌的体外抗菌性能.结果表明:水不溶性壳聚糖酸溶液均表现出抑菌活性,且随着浓度的增大而抑菌活性增强;中等分子量(7.8×104)壳聚糖比大分子量(3.8×105)壳聚糖和低分子量(1.7×104,2.3×103)壳聚糖抗菌作用强.  相似文献   
116.
植物生理信息采集处理系统研究   总被引:1,自引:0,他引:1  
以虚拟仪器理论为基础研制的植物生理信息采集处理系统.应用了传感器技术、自动测量技术、微计算机软硬件技术及数据的数学处理方法.植物生理信息采集处理系统由传感器、信号调理电路、数据采集卡、通用计算机和数据采集软件、数据处理软件构成,实现了植物生理信息多通道数据的实时自动采集和处理功能.系统具有测量集成、植株活体无损测量、信息数字化、全自动记录、用数据库管理数据等特点.  相似文献   
117.
液—液相转移催化法合成N,N′—二芳氧基乙酰基芳二胺   总被引:5,自引:0,他引:5  
陈继畴  杨素铀 《应用化学》1992,9(6):103-106
  相似文献   
118.
Cytoskeletal involvement in cotton fiber growth and development   总被引:1,自引:0,他引:1  
The organization of cellulose microfibrils in plant cell walls influences physical properties of the wall and thus cell expansion characteristics. Developing cotton fiber represents an excellent model system for the analysis of the biological regulation of cell wall patterns. Current research indicates that the cytoskeleton has a major role in directing the deposition and organization of cellulose microfibrils in the cell walls of many plant systems, including developing cotton fibers. Both microtubules and microfilaments appear to be involved in regulating changes observed in microfibril patterns during fiber development. The polylamellate architecture of the fiber wall can be attributed to changes in the orientation of cytoplasmic microtubules which appear to direct the orientation of microfibril deposition in each successive layer of the fiber wall. In the drug-induced absence of microtubules, cellulose is deposited in the fiber wall in a swirled pattern of bundled microfibrils. Interaction between adjacent microfibrils may influence cell wall organization on a localized level. In contrast to the direct involvement of microtubules on wall organization, microfilaments appear to be indirectly involved in the deposition of cellulose microfibrils. Current evidence indicates that microfilaments influence wall organization by controlling changes in microtubules patterns. Although a greater understanding of the relationship between the cytoskeleton and the fiber wall is needed, there is sufficient evidence to indicate that genetic manipulation of cytoskeletal components is one path toward future direct manipulation of cell expansion characteristic in many plant systems and may lead to improvements in the textile qualities of cotton fibers.  相似文献   
119.
Slurry-ETA-AAS is used to determine lead in plant materials. The stability of the slurry was studied and it was shown that, when NH4H2PO4 modifier is added, the shape of the time resolved absorbance signal for the sample and the standards is similar and the calibration line obtained using aqueous standards is parallel to the standard addition line. Results obtained for several reference materials (lead contents between 6.1 and 64.4 g/g) were in good agreement with the certified value, the relative standard deviation being 3–9%.  相似文献   
120.
植物生长促进剂WD-5和WD-9于苗期或苗、苔期各喷施150mg/kg,其叶面积增大,干物质量增加,光合强度增强;苗期喷施者的GAs和IAA含量分别比对照高37.4%~618.2%和38.2%~114.4%,但ABA含量也比对照高,因而易产生早衰现象.WD-5苗期喷施增产10.2%,苗、苔期各喷一次增产14.7%;WD-9苗期喷施增产13.1%,苗、苔期各喷一次增产9.0%.  相似文献   
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