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.     

林下斜纹夜蛾的发生与防治

斜纹夜蛾是一种间歇性猖獗发生的杂食性害虫,严重危害林下农作物生长发育,斜纹夜蛾1a繁殖6～7代,危害时间长达90 d,而且防治难度大.     

Can sieving size affect the determination of soil available micronutrients?

<正>Dear Editor,Globally, approximately two billion people suffer from micronutrient deficiencies(Tulchinsky, 2010; Myers et al.,2014).Soil micronutrient availability is of great importance for the evaluation of soil fertility and the determination of appropriate measures for improving crop quality and human health.The diethylenetriamine-penta-acetic(DTPA)     

我国驯鹿皮蝇蛆病的研究概况

在我国,驯鹿主要集中在内蒙古自治区根河市,数量已然不多,是一种濒危的动物,目前内蒙古自治区已经采取了必要的措施,对其进行了保护,并取得了满意的成效。然而某些寄生虫病严重地影响着驯鹿业的健康发展,其中驯鹿皮蝇蛆病就是其中的一种,给驯鹿养殖业造成了很大的损失。在我国关于驯鹿皮蝇蛆病的科技文献几乎空白,因此,本文对驯鹿皮蝇蛆病的病原体、流行病学、致病状况、防治等方面做一个综合性的概括,以增加人们对此病的了解,也为以后对此病的进一步研究提供一些参考。     

豫桃1号的栽培技术

通过严格疏花、疏果,适时套袋,因地因树采用适宜树形,强化树体管理防止缩果病等措施,豫桃1号在豫北10月下旬成熟,平均单果重250g,最大可达550g,外观漂亮,品质极上,可溶性固形物含量18.2%。     

氮磷钾养分配比对温室土培黄瓜产量及品质的影响

在日光温室内,采用盆栽方式研究了不同氮磷钾养分配比对土壤栽培黄瓜产量及其品质的影响。结果表明：增加磷素用量和比例可以显著提高黄瓜的产量;适量氮钾肥配合增施磷肥可以增加果实中可溶性蛋白含量,适量氮磷肥配合增施钾肥可以改善果实品质,提高可溶性糖和维生素C含量,降低硝酸盐含量。     

电商平台主导下中小型饲料企业的供应链融资研究

由于固定资产较少和不健全的财务制度造成中小型饲料企业很难从金融机构中获取贷款,导致其规模扩张和发展受到了制约.随着互联网和大数据技术的发展,电商平台主导下的供应链融资模式为中小型饲料企业融资提供了新的途径.本文阐述了电商平台主导下供应链融资的优势和模式,并提出了相关政策建议,为缓解中小型饲料企业的融资问题提供一些参考.     

马关县草果种植地的施肥效果试验

在马关县仁和镇的4年生草果种植地开展了施用不同量的农家肥、钾肥、普钙和复合肥促进草果植株开花结实效果的试验。结果表明:对该地的草果种植地进行合理的施肥能有效促进草果植株叶芽、花芽的分化,提高其结实率及结实量。各施肥处理的草果植株在叶芽数量、花芽数量、结实率及结实量等4个指标上均优于不施肥的对照,分别比对照提高了24.4%~204.9%、22%~97.6%、5.4%~36.9%和72.4%~442.3%。各施肥处理的草果植株在叶芽数量及结实量2个指标上存在极显著的差异,而在花芽数量及结实率2个指标上无显著差异。综合各施肥处理的草果植株结实量及结实率,在马关县及其土壤状况相似的草果种植地较佳的施肥肥种为钾肥或复合肥,其施肥量为钾肥200 g/株(丛)或复合肥400 g/株(丛),前者草果植株单株(丛)的结实量达8.46 kg,比不施肥的对照高442.3%,后者草果植株单株(丛)结实量达7.82 kg,比不施肥对照高401.3%。     

利用表面等离子共振技术检测牛奶中的朊蛋白

利用生物传感器——表面等离子共振传感器建立在活体动物中检测朊蛋白的方法,依据抗原—抗体特异性原理检测牛奶中朊蛋白。结果表明:应用表面等离子共振技术进行检测,1 h以内即可达到在缓冲液中标准最低检测限30 ng/mL的水平,牛奶样品的最低检测限是120 ng/mL。