《植物及植物生理》课程能力教学改革初探

能力教学体系突出“以能力为本位”的职业教育思想,针对职业岗位群,以构建模块化的能力领域作为教学内容,具有较强的实践性与职业性。农业职业学校在借鉴能力教学模式与运用传统教学方法相结合的过程中,不可避免地会在教学观念、教学内容、教学方法、教学手段、教学评价等方面发生变革。     

CBE教学模式在高职工科教学中的应用分析

CBE是英文Competency Based Education的缩写。这个词语的含义是“以能力培养为中心的教学体系”。比起单纯的文化知识的吸收，它对知识的实际操作和运用更加重视。在这个教学模式中，“能力”是非常被看好的，在学习中提升自身能力，是CBE教学模式的最终目标。它强调的是职业或岗位所需能力的确定、学习、掌握和运用。如何改进教学模式，从而实现更高效率的教学，一直是教育界研究探讨的话题。CBE教学模式为高职学校提供了一个合理的参考模板，采用CBE教学模式已在高职学校范围内取得了良好的收益。     

New Citrate-Bicarbonate-Ethylenediaminetetraacetate (CBE) Method for Chemical Extraction of Hydrous Iron Oxides from Plant Root Surfaces

In the present study, the sodium citrate, sodium bicarbonate, and ethylenediaminetetraacetate (CBE) method was evaluated for iron (Fe) extraction from plant root surfaces and compared with the dithionite-citrate-bicarbonate (DCB) method. Iron plaque on root surfaces was induced by growing rice seedlings in soil with 1.8 mM Fe²⁺. Iron plaque was extracted following CBE and DCB methods. The effects of pH, temperature, and incubation time of these methods on Fe extraction from root surfaces were also examined. Iron extraction of CBE and DCB methods did not differ significantly (P < 0.05) at pH between 6 and 8, whereas Fe extraction decreased substantially for further increase of the pH of CBE and DCB solution. In some instances, there were significant differences between CBE and DCB methods in extracellular Fe extraction for temperature and incubation time. The average Fe extraction of CBE and DCB methods were 94% and 81%, respectively, indicating that CBE method would be a better choice for Fe extraction from plant roots. The recommended optimal conditions for CBE method are pH 8, volume of the solution 30 mL, incubation time 30 min, and solution temperature 22 ± 2 °C.     

CBE教学方法中的启发式教学

CBE教学提倡教学民主，课堂介导师生多向交往，以培养学生能力为重点，充分和启发式教学法，从而达到高等职业人才的培养要求。     

Germplasm resources of Vitellaria paradoxa based on variations in fat composition across the species distribution range

The karité (Vitellaria paradoxa Gaertner) is an economically important African tree with significant but little studied variation across its broad distribution range. Differences in economically important fat characteristics were determined for 42 karité populations in 11 countries. The results showed very high variability in all measured parameters both within and between populations. Kernel fat content range is generally 20–50%. Fatty acid composition is dominated by stearic (25–50%) and oleic (37–62%) acids. The variable relative proportions of these two fatty acids produces major differences in karité butter consistency across the species distribution range. The principal triglycerides are stearic-oleic-stearic (13–46%) and stearic-oleic-oleic (16–31%). Ugandan karité fat is liquid and requires fractionation to obtain a butter. West African karité butter is more variable, with soft and hard consistencies produced within the same local populations. The hardest butters are produced on the Mossi Plateau in Burkina Faso and northern Ghana. The implications of distinctive population characteristics as germplasm resources for the chocolate and cosmetic industries are discussed.This revised version was published online in November 2005 with corrections to the Cover Date.