Impact of organic manure and chemical fertilizers on artemisinin content and yield in Artemisia annua L

Artemisinin isolated from the aerial parts of Artemisia annua L. is a promising and potent antimalarial drug. It posses remarkable activity against both chloroquinine resistant as well as chloroquinine sensitive strains of Plasmodium falciparum. It is also useful in the treatment of cerebral malaria. The relatively low content of artemisinin in A. annua and unavailability of cost effective and viable synthetic protocol however, are major obstacles to the commercial production of the drug. The enhanced production of artemisinin is hence, highly desirable, which can be achieved by adequate and judicious supply of plant nutrients. The present experiment was therefore, designed to study the effect of organic manure (15 tonnes ha⁻¹) and chemical fertilizers (N₄₀₊₄₀, P₄₀, K₄₀, S₁₅₊₁₅ kg ha⁻¹; nitrogen, phosphorus, potassium and sulphur) on the accumulation of artemisinin and biomass in various plant parts through the developmental stages of A. annua L. Artemisinin yield (kg ha⁻¹) was also determined through the developmental stages of A. annua L. Artemisinin content and artemisinin yield of dried leaves were increased significantly at pre-flowering stage in the plants treated with NPKS (27.3% and 53.6%) and NPK (18.2% and 33.5%), respectively, when compared with control. Maximum dry yield of leaf ranging from 2596 to 3141 kg ha⁻¹ was observed at pre-flowering stage with various treatments.     

钾肥用量对油菜产量及钾素利用效率的影响

通过11个大田试验研究了钾肥用量对油菜产量、养分含量、养分累积量及钾肥利用效率的影响。结果表明,施钾（K2O）60、120和180kg/hm2与不施钾相比平均籽粒产量分别增加16.8%、21.6%和19.8%,籽粒含钾量增加2.9%、9.1%和7.8%,植株地上部钾素总累积量提高42.9%、63.0%和82.2%。说明施钾能提高油菜籽产量、提高油菜对钾素吸收和累积。油菜钾肥农学利用率、偏生产力、表观利用率和生理利用率均随钾肥用量的增加而显著下降,100kg籽粒需钾量随钾肥用量的增加而增加。综合结果表明,湖北省油菜钾肥高产高效生产的适宜推荐范围为60~120kg K2O/hm2。     

不同品种甘蔗对钾素吸收差异性的研究

研究了温室沙培条件下不同品种甘蔗在0.02和2 mmol/L钾水平处理下的吸钾特性与钾利用效率的关系。结果表明:施钾促进甘蔗根部、茎(叶)部生长,降低根冠比,提高光合速率,有利于生物量的积累;低钾胁迫,促进粤糖159(YT159)根系生长,增加吸收面积,提高根际钾素有效性。随着钾水平的提高,粤糖2号(YT2)和新台糖22号(ROC22)的根系也随着生长,YT159的根系生长则受到抑制;在两种钾水平的处理下,YT159的生物量、根系形态指标值、光合速率都比ROC22和YT2要高,说明YT159是钾高效品种。从低钾到高钾处理中,YT159的生物量增幅小,发达的根系使其能够正常生长,因此,YT159也是耐低钾品种。     

Potassium acetate-catalyzed acetylation of wood at low temperatures I: simplified method using a mixed reagent

Ezomatsu wood blocks were acetylated in a mixture of acetic anhydride and acetic acid containing excess potassium acetate (KAc). The mixture method enabled rapid acetylation at 120°C: a 20% weight gain (weight percent gain; WPG) was achieved within 30 min while the WPG did not exceed 18% after 120 min of conventional uncatalyzed acetylation. At 40°C, however, a satisfactory WPG was not achieved with the mixture method because both the wood swelling and KAc concentration in the reagent solution were limited at that temperature. In addition, the antiswelling efficiency attained by the mixture method was irregularly low, probably because of nonuniform reaction involving shrinkage of the cell lumina. These results suggest that the mixture method is not advantageous for low-temperature acetylation, whereas it enables simple and rapid acetylation at high temperature.     

富钾基因型烤烟的钾积累及根系生理特性

采用室内营养液培养(钾浓度为3 mmol L^-1)的方法, 以富钾基因型烤烟农大202与2个一般型品种净叶黄、NC89为材料, 研究富钾基因型烤烟钾积累及根系生理特性。结果表明, 3个烤烟品种根和茎中钾积累量无显著差异, 但农大202的叶片钾积累量、根系活力和根系总活力、根系H⁺分泌量、根系阳离子交换量(CEC)、根系可溶性蛋白含量和ATPase活性均极显著高于另两个品种。净叶黄、NC89间除根系活力和根系H⁺分泌量差异达显著水平外, 其他根系生理特性差异均不显著。根系钾吸收动力学参数结果显示,农大202苗期钾离子最大吸收速率(V_max)较高而米氏常数(K_m)和钾离子吸收临界浓度(C_min)较低, 而旺长期的V_max、K_m及C_min均较高, 说明其根系具有较高的钾吸收速率, 但旺长期后耐低钾能力较差。     

黄淮海三省两市作物秸秆及其养分资源利用现状分析

摘要：基于历年统计数据和农户调研数据,分析了黄淮海地区作物秸秆及其养分资源的利用情况。结果表明：2007年黄淮海地区秸秆资源数量达到2.1亿t,秸秆N、P2O5、K2O、C养分资源产生量分别在189.8、60.0、298.2、8944.8万t。从秸秆资源利用来看,2006年秸秆还田比例较2000下降6.1%,其中河北省秸秆还田比例上升16.7%,河南和山东两省秸秆还田比例分别下降13.6%、12.6%。从主要作物秸秆还田比例分析,河北省秸秆还田比例中,小麦秸秆、玉米秸秆还田比例历年平均分别达到65.1%、53.0%;河南和山东分别为56.5%、57.1%,44.8%、18.1%。作物秸秆养分还田情况表明：各种秸秆养分中,N、C养分还田比例较低,只有不到50%,大量损失到环境中去; P2O5、K2O养分还田比例较高,平均在60%以上,这与假设的秸秆作燃料和饲料养分的还田率有关,估算中假设大部分畜禽排泄物和秸秆燃料的灰分能够及时还田。因此,加强畜禽粪便和灰分的管理,增加其还田比例,是提高养分循环利用率和减少秸秆养分利用过程中损失的重要途径。     

不同施钾量对土壤钾素动态的影响

通过定位试验研究了不同钾肥用量情况下土壤钾素的动态变化,结果表明:在完全不施肥或只施用氮、磷肥的情况下,土壤速效钾含量呈现逐年下降趋势,平均每年下降2mg/kg。在施用氮、磷肥的基础上,钾肥用量在112.5kg/hm2(K2O)时可维持土壤钾素原有水平;钾肥用量在225kg/hm2时可提高土壤速效钾含量以及土壤速效钾占土壤全钾的比例,改善土壤钾素状况。     

我国烟草钾素营养的研究现状及探讨

分析了钾对烟草品质的影响情况,钾已成为提高我国烟草品质的重要限制因素,阐述了影响我国烟草含钾量的主要因素以及钾营养研究现状,提出了提高我国烟叶含钾量的有效途径。     

Influence of pasture botanical composition and fertilization treatments on tree growth

Silvopastoral systems, which combine tree and pasture production, are more complex ecosystems than exclusively agronomic systems. Good silvopasture management should seek to increase positive interactions (or synergies) and reduce negative interactions among system components (soil, trees, grass and cattle) to increase global system productivity. Tree growth and pasture production within such systems can be optimized through appropriate species selection and fertilization. The aim of the present study, carried out over the course of 3 years, was to compare how traditional fertilisation, sewage sludge dose, and potassium affect pasture-tree competition, botanic composition and tree growth in a silvopastoral system located on agricultural land during the early years of system development. The addition of potassium is recommended for improving tree growth in silvopastoral systems with slightly acidic soil, especially if the pasture has high legume content. White clover is a good choice of species for silvopastoral systems because it promotes tree growth. Our study revealed that pasture production improved when sewage sludge was used as a fertiliser, but annual production was still more strongly dependent on weather conditions.     

氮磷钾硅肥对香稻桂香占产量及品质的影响

为了确定香稻品种桂香占施肥方案,探讨不同施肥水平与各个影响产量、品质的因素之间的关系,采用了施用氮、磷、钾和硅对桂香占产量及品质影响.在α=0.5显著水平剔除不显著项后,分析结果显示尿素、过磷酸钙、氯化钾、Na2SiO3.9H2O分别施用26,0,48,56 g/m2时,产量达最大值5 352.6 kg/hm2.单因素中对产量影响:P>N,且K,Si无影响.互作因素影响中:K与Si互作(产量与之正相关)>P与K互作(产量与之负相关)>P与Si(产量与之负相关).