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151.
152.
为了探究利于三七生长发育和降低发病率的灌溉施肥模式。以3年生三七为研究对象,采用大田试验,试验共设置3个灌水水平:W1(低水,0.5FC,FC为田间持水量)、W2(中水,0.7FC)、W3(高水,0.9FC),设置4个施肥水平:F1、F2、F3、F4,全年施肥量均为96 kg·667m-2,根增重期∶苗期∶花期∶果期的施肥比例分别为25%∶25%∶25%∶25%、20%∶25%∶30%∶25%、15%∶30%∶30%∶25%和10%∶40%∶20%∶30%。分析生育期不同施肥量和灌溉耦合对三七生长特性、光合特性、干物质积累和发病率的影响。结果表明:W2F4处理的地上部分鲜重、地上部分干重、根鲜重、根干重都最大,其苗期和果期的株高和茎粗也最大;茎粗增量最大的处理为W1F3和W2F3,株高增长量最大的处理为W2F3和W2F4;三七花期的净光合速率(Pn)、叶片瞬时水分利用效率(WUE)和光能利用效率均高于果期;6、7、8月发病率较低的处理为W2F4和W2F3。综上可知,适当的水分胁迫和苗期、果期增肥有利于提高三七产量,降低发病率。 相似文献
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154.
Panax wangianus (Syn. Panax pseudoginseng) S. C. Sun (Araliaceae) is a critically endangered, medicinal plant of North-East India. The objective of this study was to determine how plant size affects flowering phenology and to evaluate the effect of climatic factors on flowering, fruiting and seed production. Data on vegetative and repro- ductive characters were monitored from 2016 individuals of Panax wangianus population in Law Lyngdoh, Smit sacred grove in Nongkrem, Shillong, India. Leaflet area was measured by a planimeter. Size variables of both vegetative and reproductive traits in different age classes were measured. Climatic factors were recorded from 2007 to 2009. Age was recorded by counting the number of bud scale scars on the rhizome. Light intensity and relative humidity were measured using a photometer, LiCor Model LI-189 and thermohygrometer respectively. Different climatic variables are correlated with vegetative and reproductive phenological events. Statistical analysis revealed that a strong positive correlation was observed between the age versus vegetative and reproductive characters, except 1%-2% plants showed neoteny. Morphological variations were observed in natural conditions on the basis of the number of prong and carpellate conditions. Phenological status revealed that most of the individuals of the age class 35-50 years and above 50 years contributed the most to flowering, fruiting and seed production. Age class was significant to predict the size of the plant and its reproductive capacity. Climatic factors such as temperature, precipitation and relative humidity show synergistic effect on both the vegetative and reproductive phases in Panax wangianus in the undisturbed Nongkrem sacred grove. The color of flowers of P. wangianus also varied depending upon the sunlight intensity. Therefore, in the view of conservationand management, the age class of 35-50 years and above 50 years is the most important for population sustainability. 相似文献
155.
本文采用乙酸乙酯作为提取溶剂,以乙酸乙酯—正已烷—氯仿作为洗脱剂,以硅胶为支持剂进行干柱层析,获得一淡黄色油状物,经IR、′H—NMR、~(13)C—NMR和MS光谱鉴定为人参环氧炔醇(Panaxydol)。 相似文献
156.
将当归、人参、桔梗3种中草药浸提液添加到绿色巴夫藻的培养液中,研究其对绿色巴夫藻的生长及叶绿素a含量的影响。结果表明:当归浸提液体积分数为1 00%~2 00%,桔梗浸提液体积分数为0 60%时,能提高绿色巴夫藻的生长及叶绿素a含量。各体积分数的人参浸提液对生长没有明显作用,但使叶绿素a的含量有不同程度的降低。因而,在绿色巴夫藻的培养过程中,可以添加一定量的当归、桔梗浸提液。 相似文献
157.
浙江省庆元县西洋参引种课题协作组 《浙江林学院学报》1989,(4)
1984年引种加拿大产的西洋参种子0.680kg。经4年引种试验,结果表明西洋参在引种地生长良好,开花结果正常,子代小苗形态和生态习性无异常变化;皂甙、氨基酸和无机元素等含量与原产地美国和加拿大基本相同。试验取得初步成果。 相似文献
158.
西洋参果实中发芽抑制物质——二苯胺的分离鉴定 总被引:5,自引:0,他引:5
利用纸层析(PC)、薄层层析(TLC)和质谱(MS)方法,首次从西洋参(Panax quinquefolium Linne)果实中提取、分离并鉴定出发芽抑制物质-二苯胺。以白菜(Brassica chinensis Linne)种子为指示植物,测定出二苯胺对其胚根生长抑制率达到50%时的浓度(中等抑制浓度-IC50)为74.13μg/mL.同时,改进了传统的将PC纸和TLC板分为十等份的抑制物质分离方法。 相似文献
159.
160.
AIM: To investigate whether excessive endoplasmic reticulum stress (ERS) is involved in the protective mechanism of Panax quinquefolium saponins (PQS) against ischemia/reperfusion (I/R) injury in rat myocardium. METHODS: The model of myocardial I/R injury in vivo was made by ligating the left anterior descending artery for 45 min followed by 24 h of reperfusion in SD rats. The hemodynamics and serum content of cardiac troponin T (cTnT) were measured. The myocardial infarct size was measured by Evans blue and 2, 3, 5-triphenyltetrazolium chloride (TTC) staining. Cardiomyocyte apoptosis was detected using in situ TDT-mediated dUTP nick end labeling (TUNEL). The protein levels of glucose-regulated protein 78 (GRP78), calreticulin (CRT), C/EBP homologous protein (CHOP), caspase-12, apoptosis-associated proteins Bax and Bcl-2 were determined by Western blotting. RESULTS: Compared with I/R group, the mean arterial pressure in PQR+IR group was decreased by 32.0%, and left ventricular±dp/dtmax was increased by 64.0% and 35.0%, respectively.The serum content of cTnT was decreased by 53.3%, the percentage of area of necrosis (AN)/area at risk (AAR) was reduced by 65.5% and the apoptosis rate was decreased by 54.9%.The myocardial pathological changes were improved. Bcl-2 protein expression was increased by 110.0% and that of Bax was decreased by 47.8%. CRT protein expression was decreased by 43.4 %, CHOP protein expression and the protein level of cleaved caspase-12 were decreased by 38.6% and 23.7% in PQS+I/R group. CONCLUSION: PQS alleviates I/R injury in myocardium by inhibition of excessive ERS. 相似文献