不同移栽期对粳稻品质的影响

采用不同移栽期对2008年辽宁省水稻区域试验中晚熟A组14个水稻品种的9个品质性状进行变异分析及主成分分析,结果表明:不同移栽期对稻米不同品质性状的影响不同;综合6移栽期稻米品质性状达优质稻谷国标的概率,胶稠度的达标率最高,垩白度表现最差,一级达标率为0;不同品质性状对移栽期变化所表现的变异程度不一致,垩白度、垩白粒率变异最大,其次是整精米率和胶稠度,长宽比的变异度最小;主成分分析中,包含糙米率、精米率、整精米率和垩白度的第一主成分因子对稻米品质的贡献最大,贡献率达42.78%,其次是胶稠度和碱消值,与前者的累计贡献率达60.72%。     

Biological characterization of French Potato virus Y (PVY) isolates collected from PVY‐susceptible or ‐resistant tobacco plants possessing the recessive resistance gene va

Improved tobacco cultivars introgressed with alleles of the recessive resistance va gene have been widely deployed in France to limit agronomical consequences associated with Potato virus Y (PVY) infections. Unfortunately, necrotic symptoms associated with PVY have been reported on these cultivars suggesting that PVY is able to overcome the resistance. A field survey was performed in France in 2007 to (i) estimate the prevalence of PVY in tobacco plants showing symptoms and (ii) characterize PVY isolates present in susceptible and va‐derived tobacco cultivars. A serological typing procedure, applied to 556 leaves collected from different French tobacco growing areas, was performed using polyclonal antisera raised against different viral species including PVY. Viral species were detected in 80·8% of leaves and PVY was present in 83·5% of infected samples. However, statistical analysis confirmed that the probability of a tobacco plant being infected with PVY is reduced in va hosts. Eighty‐six PVY isolates were mechanically inoculated on one susceptible and three va‐derived tobacco cultivars used as indicator hosts to define virulence of these isolates against alleles 0, 1 and 2 of the va gene. Both qualitative and quantitative analyses showed that 55 PVY isolates were able to overcome the three va alleles. Moreover, the monitored biological diversity of PVY isolates was higher in the susceptible tobacco hosts than in the va‐derived ones. This study helps to understand consequences of the deployment of the va gene in tobacco on diversity and virulence of PVY isolates.     

万寿菊根提取物对西瓜枯萎病菌的抑菌活性成分及作用机理研究

本文研究了万寿菊根提取物中西瓜枯萎病菌的抑菌活性成分及其抑菌作用机理。结果表明,在4类主要化学物质中,精油类含量最高(59.8%),且抑菌效果最佳;10mg/mL精油提取物的抑制率在24、36和48h分别为62.83%,58.31%和56.30%。在西瓜枯萎病的3个主要发病期(苗期、伸蔓开花期和座果期)施用精油提取液,能有效抑制西瓜枯萎病菌,促进植株生长,同时提高西瓜植株的POD和SOD酶活性,并维持CAT活性,有效减轻了西瓜枯萎病菌对植株的毒害作用。     

中国土地利用社会经济环境综合评价方法(英文)

稳健主成分分析(RPCA)法可用于评价土地利用的社会经济环境。该文展示了RPCA法在土地利用社会经济环境综合评价中的应用。利用RPCA法并基于土地利用的社会经济环境的区域分异特征将中国土地利用社会经济环境划分为8个分区,分别代表土地利用社会经济环境的8个级别。研究表明,采用RPCA法不易受到土地利用社会经济环境各成分要素异常值影响,所获得的土地利用社会经济环境分区较为科学与合理。由此可见,应用RPCA法可以有效地提取土地利用社会经济环境表征指标,可应用于提炼土地利用社会经济环境区域分异特征。     

^15N Isotope Techniques for Estimating Effects of Urea-N Fertilizer Application Rate on Yields and Nutrient Contents of Pakchoi Cabbage and Asparagus Lettuce and Nitrogen Utilization Efficiency

A pot experiment combined with^15N isotope techniques was conducted to evaluate effects of the varying rates of urea-N fertilizer application on yields,quality,and nitrogen use efficiency （NUE） of pakchoi cabbage （Brassica chinensis L.） and asparagus lettuce （Lactuca saiva L.）.^15N-labbled urea （5.3515N atom %） was added to pots with 6.5 kg soil of 0.14,0.18,0.21,0.25,and 0.29 g N/kg soil,and applied in two splits：60 percent as basal dressing in the mixture and 40 percent as topdressing.The fresh yields of two vegetable species increased with the increasing input of urea-N,but there was a significant quadratic relationship between the dose of urea-N fertilizer application and the fresh yields.When the dosage of urea-N fertilizer reached a certain value,nitrate readily accumulated in the two kinds of plants due to the decrease in NR activity; furthermore,there was a linear negative correlation between nitrate content and NR activity.With the increasing input of urea-N,ascorbic acid and soluble sugar initially increased,declined after a while,and crude fiber rapidly decreased too.Total absorbed N （TAN）,N derived from fertilizer （Ndff）,and N derived from soil （Ndfs） increased,and the ratio of Ndff and TAN also increased,but the ratio of Ndfs and TAN as well as NUE of urea-N fertilizer decreased with the increasing input of urea-N.These results suggested that the increasing application of labeled N fertilizer led to the increase in unlabeled N （namely,Ndfs） presumably due to ＂added nitrogen interaction＂ （ANI）,the decease in NUE of urea-N fertilizer may be due to excess fertilization beyond the levels of plant requirements and the ANI,and the decrease in the two vegetable yields with the increasing addition of urea-N possibly because the excess accumulation of nitrate reached a toxic level.     

模拟葡萄汁中添加可同化氮对酵母菌酒精发酵的影响

【目的】研究添加可同化氮对模拟葡萄汁酒精发酵的影响,确定利于酵母菌酒精发酵的可同化氮水平,为葡萄酒酿造过程中可同化氮的添加提供依据。【方法】设计3种氮素添加方式,分析不同质量浓度可同化氮和添加处理下模拟葡萄汁的酒精发酵过程及产物的差异,对各处理酒精发酵过程中的酵母菌数量和还原糖含量及酒精发酵结束后的游离氨基酸、铵态氮、有机酸、香气成分含量进行测定和分析。【结果】随着可同化氮质量浓度的升高,酵母菌数量增加,酒精发酵速率增大,二次添加可同化氮使酵母菌数量增加较快,糖消耗速率增大;可同化氮质量浓度为240mg/L时,有机酸的总生成量最高,二次添加可同化氮降低了有机酸的总生成量,提高了乳酸、乙酸和琥珀酸的生成量,但柠檬酸的生成量有所降低;可同化氮质量浓度的升高有利于生成较多的香气成分,二次添加处理可以提高高级醇和酯类的生成量,但对酸类生成量无明显影响。【结论】可同化氮是酵母菌进行正常酒精发酵必需的大量营养元素,可同化氮质量浓度低于90mg/L时,添加有机氮(氨基酸)和无机氮(铵态氮)均能促进酵母菌完成酒精发酵,可同化氮质量浓度的升高有利于生成较多的香气成分。     

美国大杏仁烘烤和贮存过程中的香气成分分析

【目的】研究美国大杏仁烘烤和烘烤后贮存过程中香气成分及其含量的变化,为美国大杏仁的加工及贮存提供理论依据。【方法】通过氯化钙柱吸附法制备样品,采用气相色谱-质谱联用仪对美国大杏仁烘烤前、后及烘烤后贮存3个月和6个月的风味成分及其含量进行分析。【结果】美国大杏仁烘烤前的主要挥发性物质有25种,烘烤后的主要挥发性物质有44种,烘烤后贮存过程中的主要挥发性物质有50种;美国大杏仁中的挥发性香气成分主要为芳香醛类、脂肪族醛类、芳香醇类、脂肪族醇类、吡嗪类及其衍生物,苯甲醛是美国大杏仁挥发性成分的主要特征香气组分。【结论】纸袋包装的烘烤美国大杏仁在37℃下贮存6个月时已经氧化变质,高含油量及高不饱和脂肪酸的存在是引起烘烤杏仁变质的主要原因,壬醛、己醛、2-辛烯醛、辛醛及庚醛等脂肪族醛类物质是烘烤美国大杏仁氧化酸败后产生不良气味的主要组分;壬醛和己醛的组分含量可以作为油脂氧化程度及确定烘烤美国大杏仁货架期的检测指标。     

船载海吊关键部件设计

船载海吊是海洋工程装备的重要工具,对提高效率、安全生产有重要意义。船载海吊是通过回转动作和改变起重臂的跨度,将起重吊钩移至本方货场上方,吊起货物后移至目标船的货场上方,放下货物。与普通起重机械相比,船载海吊没有行走机构,其关键部件包括起升机构、回转机构和变幅机构,即通过起升机构提升或下降货物,通过回转机构在水平方向沿圆弧弧线运移物品,通过变幅机构改变吊臂倾角实现变幅。当然还需要考虑海上波浪运动对作业的影响,船载海吊还包括波浪补偿装置,提出了海浪补偿系统的操作流程。最后,基于AutoCAD对船载海吊进行了三维建模。     

Effect of different dietary ratios of sunflower and linseed oils on growth and carcass traits of rabbits

As part of an experiment aiming to modify the meat fatty acid profile, this work studied the growth and carcass traits as affected by various dietary ratios of sunflower oil and linseed oil. A diet without added oil served as a control (C). Four other diets were equally 4% oil-enriched but they differed in the incorporation ratios of sunflower oil (S) to linseed oil (L), i.e. 4% S to 0% L (diet 4%S), 3% S to 1% L (diet 3:1%SL), 2% S to 2% L (diet 2:2%SL) and 0% S to 4% L (diet 4%L). The oil-rich diets had slightly higher digestible energy contents (11.4 vs 10.6 MJ/kg) than the C feed. In each group 10 litters of 7 to 9 Pannon White kits per litter were studied in the pre-weaning period from 21 to 35 days old. Growth and slaughter traits were assessed with 50 and 30 rabbits per group, respectively. No significant effects of diets were found on litter and doe performances. The only significant differences in growth performance of the C, 4%S, 3:1%SL, 2:2%SL and 4%L rabbits were for the 35–49 day feed intake (88, 86, 84, 84 and 83 g per day, respectively, P = 0.046), the 35–84 day growth rate (36, 38, 37, 35 and 37 g/day, P = 0.034) and the 84-day body weight (2608, 2703, 2664, 2565 and 2628 g, respectively, P = 0.022). There were several significant differences in carcass traits including the weight of reference carcass (1357, 1391, 1388, 1380 and 1369 g, respectively, P = 0.004) and left longisimus dorsi meat (78, 79, 81, 81 and 76 g, respectively, P = 0.046) of rabbits. The diets had major effects on the L*, a* and b* colour values (lightness, redness and yellowness) of meat and fat. Carcass colour of the C and 4%S rabbits was closer and the 4%L rabbits was further from the European consumer's preference of light coloured, less red and slightly yellow rabbit meat. Our result reveals the importance of age and body weight at slaughter. Taking the growth and slaughter performances and, the recent belief of human health benefits from lower n− 6/n− 3 FAs dietary ratios into account, the 2:2%SL diet seems most appropriate if the interests of the raisers, meat processors and buyers are considered equally.     

食品营养与检测专业高素质应用型人才培养的创新与实践

通过调查食品企业对品质检测人员的意见要求,对食品营养与检测专业原有教学模式进行改革,重新制定培养目标,建立了以能力培养为主线,突出实践教学环节的课程体系;加强实践性教学环节;构建实验教学和配套的考核体系;实行＂学院行政—教研室—教师线＂、＂学院党总支—辅导员—班主任线＂双线管理的综合素质培养模式。