Field evaluation of insect-resistant transgenic Populus nigra trees

The performance of insect-resistant transgenic poplar trees (Populusnigra) expressing a Cry1Ac gene from Bacillus thuringiensis subsp. Kurstaki HD-1 against poplar defoliators was evaluated in the field at the Manas Forest Station in Xinjiang Uygur Autonomous Region during1994–1997. The results showed that the average percentage of highly damaged leaves on the transgenic trees was 10% while that on the control trees in nearby plantations reached 80–90%. The average number of pupae per m² of soil at 20cm depth in transgenic poplar plantation was 18 which was only 20% of that found in the non-transgenic control field. The number of pupae and the leaf-damage on transgenic trees described above are all far below the threshold set for chemical protection measures. The non-transformed poplar trees grown in the same plantation with the transgenic trees were also protected indicating that cross protection occurred between these two kinds of trees. Insect-resistant transgenic poplar trees have a potential application value in afforestation. This revised version was published online in August 2006 with corrections to the Cover Date.     

Effect of stachyose supplementation on growth performance, nutrient digestibility and caecal fermentation characteristics in broilers

1. The objective of this study was to evaluate whether the oligosaccharide stachyose enhances gastrointestinal tract health by fermentation and proliferation of desirable bacteria species and thus affects growth performance and nutrient digestibility in broilers. 2. A total of 432 1-d-old male Arbor Acres (AA) broilers were randomly allocated to one of 6 treatments, with 12 replicate pens per treatment and 6 birds per pen. Chicks were fed a maize-hamlet protein 300 (HP300) basal diet with 0, 4.0, 8.0, 12.0 or 16.0 g/kg stachyose. A sixth diet contained no HP300 but soybean meal (SBM) and provided 8.7 g/kg stachyose and 3.1 g/kg raffinose. The duration of the study was 42 d. 3. Stachyose contents above 12.0 g/kg depressed group body weights, average daily gain and feed/gain but not feed intake during the whole experimental period. Broiler growth decreased linearly and quadratically with increasing stachyose content. No differences were detected between diets supplemented with 12.0 g/kg stachyose and SBM. 4. Nutrient digestibility tended to decrease but not significantly with increasing stachyose. 5. Stachyose content had no significant positive effects on caecal pH, microflora population and the resulting short-chain fatty acid (SCFA) metabolites during the 42 d experiment, with only butyrate differing significantly in the initial period.     

作物遥感估产的现状及其展望

 总结了国内外作物遥感估产的状况，并对作物遥感的技术集成和便利化服务、数据处理、农业标准化、农学机理、扩大用户需求共4个方面作了展望。     

板栗壳色素的提取研究进展

板栗壳色素是一种天然色素,具有一定的抗氧化和抑菌作用。综述了板栗壳色素的理化性质,重点介绍了板栗壳色素的提取方法,展望了板栗色素的应用前景。     

高效液相色谱(High-performance liquid chromaography)测定水产品中孔雀石绿及其代谢物的残留量的检测方法

本中心应用《水产品中孔雀石绿残留量的测定液相色谱法》（SC／T3021—2004）检测方法，多次对实际水产品中孔雀石绿及其代谢物的残留量进行检测，总结了一些经验并对方法中的一些环节进行了改进，使检测方法更加科学，回收率更合理，符合要求，检出限更低。     

东方百合L_sCCR1基因的克隆及表达分析

百合茎秆的挺度直接关系到百合花采收后的货架寿命等重要商品性状,而这些商品性状与植物茎秆中的木质素的含量高低有关.本文应用RLM-RACE技术,从东方百合索蚌植株中克隆了木质素合成相关基因一肉桂酰辅酶A还原酶,定名为LsCCR1.该基因cDNA全长为1 499 bp,包括完整的阅读框,编码388个氨基酸.多重比对分析发现百合LsCCR1基因与其他植物上已经发现的CCR基因同源性多介于55%～66%之间.利用半定量PCR检测LsCCR1基因在百合不同组织中的表达差异,结果显示LsCCR1基因主要在百合的茎秆中表达,根部次之,叶片、鳞茎及花蕾中表达量较少,其表达模式与拟南芥、桉树及大麦中CCR基因的表达模式类似.     

Effects of nitrogen and water stress on the rehydration,endogenous hormonal regulation and yield of maize

Water scarcity is known to be a strong limiting factor affecting maize grown and yield in cold semi-arid regions. Numerous studies have shown that rehydration improves maize growth. Our study aimed to explore the effects of rehydration treatments on maize growth and yield under water and nitrogen stress during different growth stages. We selected the drought-tolerant maize variety Nendan 19 (ND19) and subjected it to water stress during the V6 (sixth-leaf), R2 (filling) and R6 (maturity) growth stages and a rehydration treatment after each stress stage. Our results indicated that N1 (N100 kg N ha⁻¹) and N3 (N300 kg N ha⁻¹) treatments significantly increased the leaf moisture status relative to water content (RWC), bound water content (BWC), free water content (FWC) and water potential (WP)) at different growth stages. Similar trends were observed in the accumulation of plant leaf and root hormones (zeatin+zeatin riboside, indole-3-acetic acid, abscisic acid and gibberellic acid), photosynthetic pigments and chlorophyll fluorescence. However, under the same water stress conditions, they decreased as the N rate increased and reached a minimum value in the S3 (water stress for N3) treatments. In addition, with growth stage advancement and extension of the rehydration time, both showed a gradual upward trend. The results showed that to save water resources in the cold semi-arid region, rehydration treatments (R2S1 and R2S3) significantly increased the photosynthetic pigments and chlorophyll fluorescence parameters, leaf moisture status, biomass, 100-grain weight, hormone content, ear characteristics and grain yield of maize.     

落叶松硫酸盐漂白浆配抄涂布原纸的试验研究

利用落叶松硫酸盐漂白浆配抄涂布原纸,结果表明,其中4种配比,即落叶松浆用量50%或70%,配用麦草浆50%或30%;或配用针叶材浆10%,桦木浆40%;或配用针叶材浆10%,麦草浆40%,所抄出原纸的主要技术指标均符合涂布原纸"特号"纸的质量标准.     

对CALIS中外文对照工具书101字段第一指示符取值的探讨

对CALIS中外文对照工具书的101字段第一指示符的取值情况进行了调研,对取值不规范、不统一的实例进行了归纳总结;结合编目工作实际,分析、探讨了中外文对照读物101字段第一指示符的取值原则。