生物有机复混肥对木薯甘蔗产量及土壤肥力的影响

针对广西土壤养分状况,利用木薯皮、淀粉渣、酒精渣,经生物发酵处理,配以合理氮、磷、钾化肥研制成生物有机复混肥。2006～2007年在木薯、甘蔗上进行施用试验。结果表明：在同等N＋P2O5＋K2O总养分施用条件下,生物有机复混肥与进口复合肥、通用复混肥比较,木薯分别增产14．16％、16．94％,甘蔗分别增产4．46％、12．40％。土壤有机质、速效氮、速效磷等养分有显著的提高。     

木薯分子标记研究进展

综述分子标记技术在木薯属植物品种(系)的鉴定、遗传多样性研究、分子遗传图谱构建以及目标性状的基因定位等方面的应用，并展望分子标记在我国木薯研究中的应用前景。     

广东木薯园土壤肥力调查及评价

分别选择国家木薯产业技术体系广州综合试验站位于广东兴宁、翁源、遂溪、开平、云安5个示范县的木薯园作为代表点,采集木薯根际表层土壤(0～20cm),测定土壤pH值、有机质含量等12个指标,分析广东木薯园的土壤肥力。结果显示,调查木薯园pH值值普遍较低(4.5～6.0),土壤酸性较强;云安和翁源土壤有机质含量处于中等水平(25.28g/kg和22.37g/kg),而兴宁、遂溪和开平较低,各样点有机质平均含量为16g/kg;整体供氮水平较低、平均含量75.95mg/kg,有效磷含量相对较高( 20mg/kg),有效钾含量分布不均匀,最低为兴宁(85.61mg/kg)、最高为翁源(252.66mg/kg);土壤交换性钙含量普遍处于中等水平(平均409.41mg/kg),交换性镁含量较低(平均39.50mg/kg);铜、铁两种微量元素并不缺乏(平均含量分别为0.66、122.86mg/kg);有效锌含量分布不均匀,表现为云安开平兴宁遂溪翁源;有效锰含量除兴宁(62.29mg/kg)外,其他4个木薯园均较低;5个木薯园均存在缺硼现象(平均含量0.13mg/kg)。因此应该合理施肥,提高广东木薯种植地土壤有机质含量水平,重视镁肥和硼肥施用,以改善镁硼缺乏现象。     

非粮燃料乙醇研究进展

非粮燃料乙醇可替代部分化石能源,其是我国应对环境、能源及粮食危机的重要途径。阐述了我国发展燃料乙醇的必要性,介绍了国内外燃料乙醇的发展现状,以及目前非粮(纤维素、木薯和甜高粱)燃料乙醇产业的技术特点及产业现状,对各种原料生产燃料乙醇的经济性进行了分析,并对产业的发展趋势和前景进行了展望。     

我国西南山区中小水电站临河(沟)型弃渣场处理措施研究

我国西南地区由于山高坡陡,建设过程中产生了大量的弃土、石、渣(后简称弃渣),这些弃渣如得不到较好的处理将造成严重的水土流失,弃渣处理正慢慢成为水保和环评验收中的制约性因素之一。因此,开发建设项目应充分重视渣场的有效处理。着重探讨西南高山区中小水电开发临河(沟)型渣场的工程措施,包括拦渣堤、排水沟等的设计简化过程。     

双工位木薯种茎切割机的设计与试验

木薯是我国重要的经济作物,拥有大量的种植面积,但木薯的切种步骤仍大量采取手工作业.为提高切种效率、减少种植户劳动量,设计了一种双工位木薯种茎切割机.运用三维建模软件UG建立三维模型,导入Adams虚拟样机中进行仿真分析,并通过制作物理样机进行试验.结果表明:各项性能指标均满足设计要求,结构合理,可替代目前木薯切种步骤中...     

丹参药渣中提取丹参酮的研究(摘要)(英文)

[目的]水浸丹参和三七后药渣中提取丹参酮并确定丹参酮成分。[方法]采用有机溶剂法提取丹参药渣中丹参酮,7种有机溶剂分别为甲醇、正己烷、石油醚、乙酸乙酯、丙酮、乙醚、二氯甲烷、三氯甲烷。以薄层层析法检测确定最佳提取溶剂。在薄层层析板上,用毛细管吸取标准品及样品,点样于薄层层析板上,每次点样依照样品浓度确定点样次数,每次点样均须用电吹风吹干。丹参酮展开剂的配方为:石油醚∶乙酸乙酯∶冰乙酸=8∶3∶1(V∶V∶V),直接观察;三七皂苷展开剂为V(氯仿)∶V(甲醇)∶V(水)=14∶6∶1,用10%H2SO4加热显色。通过高效液相色谱法确定丹参药渣中丹参酮成分。高效液相色谱法(HPLC):高效液相色谱仪为美国Waters2695-2996DAD;色谱柱为HypersilODS25μm(4.6mm×150.0mm)fromElite;进样量,10μl;体积流量,1.0ml/min。洗脱液A为水,B为甲醇。洗脱条件,初始时,A为40%,B为60%;5min时,A为40%,B为60%;20min时,A为20%,B为80%;30min时,A为20%,B为80%。[结果]乙醚为丹参药渣中提取丹参酮的最佳溶剂。水浸丹参和三七后干药渣,先经乙醇提取得到脂溶性提取物,再以乙醚为溶剂进行索氏提取,丹参酮混合物得率为2.17%;高效液相色谱法检测,丹参酮混合物中丹参酮ⅡA、次甲丹参醌、隐丹参酮、丹参酮I含量分别为3.62%、1.02%、2.56%、2.75%。[结论]丹参药渣中丹参酮成分与药材丹参基本一致,丹参药渣可以作为一种丹参酮资源,具有开发利用的价值。     

木薯内源细胞分裂素含量对块根淀粉积累的影响

[目的]探讨木薯内源细胞分裂素(CTK)含量与块根淀粉积累的关系,为高淀粉木薯品种选育及栽培提供理论依据.[方法]以低淀粉木薯品种华南124和高淀粉木薯品种辐选01为试材,测定不同生育时期木薯叶片、茎秆和块根中的CTK含量与淀粉积累量,并分析两者间的相关性.[结果]华南124叶片CTK含量呈先下降后缓慢上升的变化趋势,辐选01则与之相反,呈先上升后缓慢下降的变化趋势.两个品种茎秆、块根CTK含量及块根淀粉积累速率均呈先上升后下降的变化趋势,淀粉含量从苗期至成熟期逐渐上升.在淀粉积累的关键时期即块根膨大中期(9月15日),辐选01叶片、茎秆和块根的CTK含量及淀粉积累速率均大于华南124,且除茎秆CTK含量外其他指标均达差异显著水平(P<0.05),说明该时期是形成高、低淀粉木薯品种淀粉含量差异的主要时期.相关性分析结果表明,华南124和辐选01块根CTK含量与淀粉积累量呈极显著正相关(P<0.01,下同),相关系数分别为0.58和0.60;华南124茎秆CTK含量和辐选01叶片CTK含量与其块根淀粉积累量呈极显著负相关,相关系数分别为-0.66和-0.75.[结论]木薯块根CTK含量对淀粉的积累起促进作用,而茎秆CTK和叶片CTK含量分别对低淀粉和高淀粉木薯品种的淀粉积累呈极显著的负向调节作用.     

Distinct strains of the re‐emergent Cassava common mosaic virus (genus: Potexvirus) infecting cassava in Argentina

Cassava common mosaic disease (CCMD) has been reported in all regions where cassava is grown in the Americas and the causal agent, Cassava common mosaic virus (CsCMV), has been identified as a mechanically transmitted potexvirus (Alphaflexiviridae). In Argentina, cassava is grown mainly in the northeast (NEA) region that shares borders with Brazil and Paraguay. Increasing incidences of CCMD were observed during the years 2014 to 2016 associated with severe leaf mosaic symptoms and yield reductions where the occurrence of CsCMV was confirmed by RT‐PCR and sequencing. In this work, the virus has been successfully purified and a double‐antibody sandwich (DAS‐) ELISA test has been developed from an Argentinean isolate of CsCMV to extend the diagnostics of the disease. A collection of 726 samples was screened and CsCMV was detected with 100% prevalence in the NEA region. Additional co‐infecting viruses were detected in some plants (64.4%); in these, CCMD symptoms correlated with CsCMV only, although more severe symptoms could be observed in mixed infected plants. Sequence analysis of the conserved RdRp domain showed a wider diversity of CsCMV isolates. Interestingly, a separate phylogenetic cluster was formed by isolates from the NEA region that only shared 77.1% to 80.3% nucleotide identity with the other clusters. These results indicate the presence of mixed strains occurring in the NEA region and suggest the presence of geographically distinct strains of CsCMV in South America.     

A novel long non-coding RNA,DIR, increases drought tolerance in cassava by modifying stress-related gene expression

Cassava is an important tropical cash crop. Severe drought stresses affect cassava productivity and quality, and cause great economic losses in agricultural production. Enhancing the drought tolerance of cassava can effectively improve its yield. Long non-coding RNAs(lncRNAs) are present in a wide variety of eukaryotes. Recently, increasing evidence has shown that lncRNAs play a critical role in the responses to abiotic stresses. However, the function of cassava lncRNAs in the drought response r...