有机酸对甘薯紫色素热稳定性与抗氧化性的影响

甘薯紫色素在酸性条件下呈稳定的红色,可作为天然红色素.优化了甘薯紫色素提取条件,研究4种有机酸不同浓度对甘薯紫色素热稳定性及抗氧化性的影响.结果表明,苯甲酸、乙酸和乙二酸可显著提高甘薯紫色素的热稳定性,程度依不同浓度而异,而抗坏血酸则显著降低其热稳定性.苯甲酸、乙酸、乙二酸和抗坏血酸可以显著提高甘薯紫色素加热后的抗氧化性,程度依不同浓度而异.     

甜高粱育种思路探讨

甜高粱生物产量高,含糖量高,乙醇转化率高,抗逆性强,是能源作物,对其合理开发利用,对我国粮食安全、能源安全具有重大意义。我国甜高粱育种水平落后,现有品种不能适应生产发展的需要。创新育种思路,可从选育粮糖兼用型品种和自交不结实的品种方面进行甜高粱品种选育。     

SUSTAINABLE NUTRIENT MANAGEMENT PACKAGE FOR COST-EFFECTIVE BIOENERGY BIOMASS PRODUCTION

Commercial fertilizer (particularly nitrogen) costs account for a substantial portion of the total production costs of cellulosic biomass and can be a major obstacle to biofuel production. In a series of greenhouse studies, we evaluated the feasibility of co-applying Gibberellins (GA) and reduced nitrogen (N) rates to produce a bioenergy crop less expensively. In a preliminary study, we determined the minimum combined application rates of GA and N required for efficient biomass (sweet sorghum, Sorghum bicolor) production. Co-application of 75 kg ha^?1 (one-half of the recommended N rate for sorghum) and a modest GA rate of 3 g ha^?1 optimized dry matter yield (DMY) and N and phosphorus (P) uptake efficiencies, resulting in a reduction of N and P leaching. Organic nutrient sources such as manures and biosolids can be substituted for commercial N fertilizers (and incidentally supply P) to further reduce the cost of nutrient supply for biomass production. Based on the results of the preliminary study, we conducted a second greenhouse study using sweet sorghum as a test bioenergy crop. We co-applied organic sources of N (manure and biosolids) at 75 and 150 kg PAN ha^?1 (representing 50 and 100% N rate respectively) with 3 g GA ha^?1. In each batch of experiment, the crop was grown for 8 wk on Immokalee fine sand of minimal native fertility. After harvest, sufficient water was applied to soil in each pot to yield ～1.5 L (～0.75 pore volume) of leachate, and analyzed for total N and soluble reactive P (SRP). The reduced (50%) N application rate, together with GA, optimized biomass production. Application of GA at 3 g ha^?1, and the organic sources of N at 50% of the recommended N rate, decreased nutrient cost of producing the bioenergy biomass by ～$375 ha^?1 (>90% of total nutrient cost), and could reduce offsite N and P losses from vulnerable soils.     

双热源半自动控温甜樱桃促成栽培系统设计与试验

为解决甜樱桃促成栽培产量和质量不稳定的问题,该研究根据甜樱桃促成栽培特点,研制了一种双热源半自动控温甜樱桃促成栽培系统。该系统以煤、柴为燃料的地炕式加热炉为补充加热方式,结合太阳能调控温度。通过与传统大棚比较,分析了该系统对甜樱桃栽培产量及经济效益的影响。结果表明:连续2 a应用甜樱桃促成栽培系统的大棚产量稳定在11 550 kg/hm2以上,优质果率超过80%,年经济效益比普通大棚高37%(2012年)和36%(2013年)。该系统采用半自动测控促成栽培环境,使环境因子的检测和报警实现自动化,明显降低了劳动强度,在甜樱桃促成栽培中推广应用,可取得显著经济效益。     

干旱胁迫与正常供水钾肥影响甘薯光合特性及块根产量的差异

【目的】干旱胁迫影响甘薯叶片光合特性及块根产量,研究通过施肥缓解干旱胁迫机理可为甘薯抗旱高产栽培提供理论依据。【方法】选用食用型甘薯品种“泰中6号”为材料,以硫酸钾(K2SO4)为供试肥料,水分处理设为土壤最大持水量的60%~70%(正常供水W1)和30%~40%(干旱处理W0); 钾肥设K0、 K1、 K2、 K3四个水平,K2O用量分别为0、 12.0、 24.0和36.0 g/m2。分析不同钾肥用量对不同生长时期甘薯叶片相对含水量、 叶绿素荧光参数、 光合特性及收获期块根产量的影响。【结果】在干旱胁迫和正常灌水条件下,施钾处理均显著增加了甘薯叶面积和叶片叶绿素含量,提高净光合速率(Pn),增加光合产物的生产和积累,提高块根产量和收获指数。两种水分条件下,块根产量均以K2处理最高, 干旱胁迫下K2与K3处理差异显著,正常灌水处理不显著。两种水分条件下,甘薯叶片光合参数对钾肥的响应存在显著差异,干旱胁迫下施钾使叶片水分利用效率(WUE)增大,气孔导度(Gs)降低,气孔阻力增大,蒸腾速率(Tr)和胞间CO2浓度(Ci)降低,水分蒸腾量减少; 而正常灌水条件下上述指标对钾肥的响应趋势相反。两种水分条件下施钾均可以增大叶片相对含水量(RWC),提高实际光化学效率(ΦPSII)和最大光化学效率(Fv/Fm),但是干旱胁迫下施钾增幅较大。【结论】干旱胁迫下适量施钾可以提高甘薯的抗旱性,增加甘薯产量,过量施钾使甘薯产量显著降低,而正常水分供应时,稍多钾肥对产量影响不显著。干旱胁迫与正常灌水条件下施钾对叶片光合参数的调控效应存在显著差异。施用钾肥可增大叶面积,提高叶绿素含量和光合性能,调节叶片气孔关闭,增大叶片气孔阻力,减少水分蒸腾损失,增加叶片相对含水量,提高水分利用效率和净光合速率; 施钾还能提高叶片PSⅡ原初光能转换效率和实际光化学效率,减少过剩激发能对光合机构的破坏,提高甘薯叶片的光合能力。干旱条件下钾肥的调节功能优于正常水肥供应。     

基于电子鼻传感器阵列优化的甜玉米种子活力检测

针对甜玉米种子活力传统检测方法操作繁琐、重复性差等不足,该研究利用电子鼻技术建立甜玉米种子活力快速检测方法。利用电子鼻获取不同活力甜玉米种子的气味信息,再结合主成分分析(PCA,principal component analysis)、线性判别分析(LDA,linear discriminant analysis)、载荷分析(loadings)和支持向量机(SVM,support vector machine)对气味信息进行提取分析,建立甜玉米种子活力的定性定量分析模型。结果显示:PCA和LDA分析均无法区分不同活力的甜玉米种子,而SVM的鉴别效果较好。全传感器阵列数据集SVM分类判别模型训练集和预测集正确率分别为97.10%和96.67%,建模时间为30.75 s,回归预测模型训练集和预测集决定系数R~2分别为0.993和0.913,均方差误差分别为2.23%和8.50%。经Loadings分析将10个传感器阵列优化为6个。优化后传感器阵列数据集SVM分类判别模型训练集和预测集正确率分别为98.55%和96.67%,建模时间为21.81 s,回归预测模型训练集和预测集决定系数R~2分别为0.982和0.984,均方差误差分别为3.80%和3.01%。结果表明:基于SVM的电子鼻技术可以实现对不同活力甜玉米种子的高效判别和预测,将传感器阵列优化为6个,判别和预测效果均有所提升。该研究为电子鼻技术应用于甜玉米种子活力检测提供理论依据。     

甘薯联合收获机高度自适应集薯装置设计与优化

甘薯收获是甘薯生产中用工量最多、劳动强度最大的环节。为了解决甘薯联合收获机集薯环节存在伤薯率高、自动化程度低等问题,该研究开展了高度自适应集薯装置的机械结构设计与控制系统搭建。系统及结构设计充分考虑物料物理性状及作业过程中的运动学与力学特性,通过新的集薯方式以满足落薯高度自适应、集薯装筐和自动卸料换筐等作业要求。通过落薯高度自适应功能减小并控制薯块下落的高度达到有效减少甘薯伤薯率与破皮率的目的。在单因素试验分析结论的基础上,以清选平台转速、落薯机构转速和落薯设定高度为试验因素,开展三因素三水平Box-Benhnken试验,以伤薯率、破皮率、微破率和损伤率为试验指标建立多元回归方程并进行响应面分析。回归模型进行多目标优化后获得装置最优工作参数组合为：清选平台转速108.07 r/min、落薯机构转速74.75 r/min、落薯设定高度18.15 cm。对优化结果进行验证试验,试验结果为：伤薯率0.39%、破皮率0.54%、微破率22.93%和漏薯率0.54%,各评价指标与模型预测值相近。研究结果可为甘薯联合收获机高度自适应集薯装置进一步设计与优化提供参考。     

Effect of Preharvest Sprays of Calcium on Cracking and ‘Schattenmorelle’ Sour Cherry Fruit Quality Harvested Mechanically

The aim of the study was to examine effect of preharvest sprays of calcium (Ca) in the form of Ca-chloride (CaCl₂), Ca-nitrate [Ca(NO₃)₂], or a mixture of Ca-formate, Ca-acetate, CaCl₂, and Ca(NO₃)₂ on cracking and quality of ‘Schattenmorelle’ sour cherry fruit harvested mechanically. The experiment was conducted in 2008–2009 at a commercial orchard in central Poland. Mature trees grew on a coarse-textured soil poor in organic matter, at a spacing of 4.0 × 1.5 m. The spray treatments of Ca were performed at 7-day intervals, starting 28 days before harvest, at the rates of 5.0–5.6 kg Ca ha^?1 per season. The trees sprayed with water were treated as the control. Fruit were harvested mechanically when peduncle-fruit detachment force dropped below 3 N. The results showed that preharvest Ca sprays caused no leaf damage. This measure did not affect yield, mean fruit weight, soluble solids concentration and titratable acidity of fruit, and weight loss of fruit during 24 h after harvest. Fruit sprayed with Ca had improved status of this nutrient, and were less liable to juicy leakage from the stem scar, rain-induced cracking, and preharvest decay caused by Glomerella cingulata. The above effects of Ca sprays did not depend on the tested material. It was concluded that preharvest sprays of Ca as CaCl₂ and/or Ca(NO₃)₂ should be recommended in ‘Schattenmorelle’ sour cherry orchards to reduce fruit losses resulting from rain-induced cracking, leakage of juice, and the incidence of cherry bitter rot.     

甜高粱茎秆液态发酵制取乙醇工艺技术

甜高粱茎秆液态发酵制取乙醇工艺技术是国家高技术研究发展计划(863计划)《甜高粱茎秆制取乙醇》(课题编号:2001AA 514040)项目中关键技术之一,本文简要的论述了该项技术的工艺流程、工作原理和性能指标。该项研究成果主要以甜高粱茎秆汁液为原料,采用固定化酵母流化床快速发酵工艺,并克服了固定化细胞技术中普遍存在的载体机械强度低、使用寿命短等技术难题,同时根据乙醇酵母的生理、生化特性制定了一套适用于高技术的乙醇生产新工艺。该项技术具有发酵速度快、发酵率高,成熟醪酒份高、残糖低、能耗低。     

氮磷钾肥配合施用对甘薯的增产效果

通过10几年来甘薯氮、磷、钾配比田间试验结果表明：甘薯每公顷施N150-225kg，N：P2O5：K2O比例以1：0.3～0.5：0.8～1.2为宜。增产效果N〉K〉P，旱地明显高出水旱轮作地。通过大面积示范推广测产统计和228个田间小区试验分析，配方施肥比当地常规施肥每公顷平均增产鲜薯3587kg和4881kg，增产效果较好。