2,4-D丁酯麦田除草效果及其对小麦安全性的研究

对小麦2叶1心至拔节前用2，4－D丁酯做茎叶处理的除草效果进行了研究。结果表明：在小麦2叶1心至返青期施用72％2，4－D丁酯乳油对小麦田越年生杂草有理想除草效果。冬前施用2，4－D丁酯对小麦有一定药害，使小麦产量受到影响，用药越早，小麦产量越低。在产量构成因素中，以穗数受药害影响最大；冬后小麦返青至拔节期施用2，4－D丁酯，对小麦产量无影响。     

Akt-mediated phosphorylation of EZH2 suppresses methylation of lysine 27 in histone H3

Enhancer of Zeste homolog 2 (EZH2) is a methyltransferase that plays an important role in many biological processes through its ability to trimethylate lysine 27 in histone H3. Here, we show that Akt phosphorylates EZH2 at serine 21 and suppresses its methyltransferase activity by impeding EZH2 binding to histone H3, which results in a decrease of lysine 27 trimethylation and derepression of silenced genes. Our results imply that Akt regulates the methylation activity, through phosphorylation of EZH2, which may contribute to oncogenesis.     

不同生长素诱导对拟南芥根生长发育的影响

利用奈乙酸(NAA)、吲哚乙酸(IAA)、吲哚丁酸(IBA)和2,4-D等4种生长素的不同浓度(0,0.01,0.02,0.05,0.1,0.15和0.2 mg/L)的溶液,分别在MS培养基上对拟南芥萌发的幼苗进行处理,对其生根情况进行测定,结果表明:4种生长素都能抑制拟南芥主根生长,促进不定根生长。2,4-D的抑制作用最明显;IBA与IAA的促进作用差异不显著;NAA在0.05 mg/L时,促进作用最强。     

小麦／玉米带田中光捕获、利用及干物质积累特点

通过间作与相应单作的比较证实了小麦玉米间作具有明显的间作产量优势，施肥对这种间作优势有促使作用。间作优势在光资源的捕获利用方面的表现主要是其提高了ＰＡＲ的捕获效率而非利用效率。小麦相对于玉米的竞争力更强，施肥有缓解这种强烈竞争的作用     

推进科研经费“放管服”改革的实践与思考

《关于进一步完善中央财政科研项目资金管理等政策的若干意见》（中办发［2016］50号）提出：“进一步推进简政放权、放管结合、优化服务,改革和创新科研经费使用和管理方式,促进形成充满活力的科技管理和运行机制”。为贯彻落实好中央文件精神,激发科技创新活力,文章就科研单位如何推进科研经费“放管服”改革的重点在加强学习培训、新政细化落地、优化管理服务、加强内控建设等方面谈了一些自己的学习思考与具体做法,并对进一步推进新政落地提出了意见建议。     

Microbial community and ovine host response varies with early and late stages of <Emphasis Type="Italic">Haemonchus contortus</Emphasis> infection

The interactions between gastric microbiota, ovine host, and Haemonchus contortus portray the ovine gastric environment as a complex ecosystem, where all factors play a pertinent role in fine-tuning each other and in haemeostasis. We delineated the impact of early and late Haemonchus infection on abomasal and ruminal microbial community, as well as the ovine host. Twelve, parasite-naive lambs were divided into four groups, 7 days post-infection (dpi) and time-matched uninfected-control groups; 50 dpi and time-matched uninfected control groups were used for the experiment. Six sheep were inoculated with 5000 H. contortus infective larvae and followed for 7 or 50 days with their corresponding uninfected-control ones. Ovine abomasal tissues were collected for histological analysis and gastric fluids were collected for PH value measurements, microbial community isolation and Illumina MiSeq platform and bioinformatic analysis. Our results showed that Haemonchus infection increased the abomasal gastric pH (P = 0.05) and resulted in necrotizing and inflammatory changes that were more severe during acute infection. Furthermore, infection increased the abomasal bacterial load and decreased the ruminal microbiome. A 7-day infection of sheep with H. contortus significantly altered approximately 98% and 94% of genera in the abomasal and ruminal bacterial profile, respectively (P = 0.04–0.05). However, the approximate altered genera 50 days after infection in the ovine abomasal and ruminal microbiome were about 62% and 69%, correspondingly (P = 0.04–0.05) with increase in some bacteria and decrease in others. Overall, these results indicate that Haemonchus infection plays a crucial role in shaping stomach microbial community composition, and diversity.     

黄土丘陵区小流域生态恢复对土壤有机碳和全氮的影响

生态恢复工程是防治黄土高原土壤侵蚀和恢复土壤肥力的重要措施,研究退耕还林还草和梯田等生态恢复措施对有机碳(SOC)、全氮(TN)的影响,对准确评估土壤固碳固氮能力和土壤碳氮循环具有重要意义。选取黄土丘陵区典型小流域5种不同生态恢复0—100cm土层为研究对象,探讨了生态恢复措施条件下,坡耕地转变为林地、草地、灌木地及梯田过程中,不同土层深度土壤SOC与TN的含量及其储量变化规律。结果表明:生态恢复措施、土壤深度对流域土壤SOC与TN有极显著的影响(P0.01)。林地与灌木地SOC与TN在土壤0—20cm土层出现富集,草地SOC与TN则在0—40cm土层出现富集,梯田的0—20cm土层SOC富集比较明显,而TN未出现富集现象。坡耕地SOC与TN未出现富集现象。坡耕地在经过不同的生态恢复措施后,土壤SOC与TN含量及储量均会有所增加。从SOC与TN之间的相关性看,林地、草地表现为极强,灌木表现为强,而坡耕地与梯田为中等。研究为提高黄土丘陵区土壤碳氮含量的评估提供科学依据,促进区域生态恢复合理规划。     

分根交替渗透胁迫与脱落酸对玉米根系生长和蒸腾效率的影响

用Hoagland溶液培养玉米幼苗, 研究分根交替胁迫对玉米根系生长和叶片蒸腾效率的影响, 实验证明： 当一半根系处于高水势, 另一半根系处于低水势, 并在一定时间间隔内交替, 4～5天后受胁迫一半根系能够形成大量侧根使根总量和总长度超过未受胁迫的对照, 当1/2根受胁迫时, 这部分根系内源ABA含量明显增加, 与气孔导度     

河西走廊灌漠土定位连施氯化铵氯离子行为的研究

定位连施氯化铵试验表明,施入土壤的氯离子15．88%～26．92%破作物吸收,47．O%～59．4%淋失至地下深层,24．7% ～26．1% 残留于O～]50cm土层;由于作物吸收和灌水淋洗作用,0～40cm作物根群集中层残留率仅占3．0%～6．6%,其中0～20cm耕作层残留率0．71％～2．4％,对作物品质与发育无不良影响,土壤性质未变。氯离子残留量与连施年限呈负相关;淋失量与连施年限呈正相关;残留量、淋失量均与施入量呈正比。指出含氯化肥应与无氯化肥搭配或间歇性施用。     

大豆产量与大豆专用肥中主要成分配比关系

采用４因素二次饱和Ｄ－最优设计,通过微机模拟计算,建立了大豆产量与大豆专用肥中氮、磷、钾、褐煤等主要成分用量的数学模型。对参试因素及其产量进行了较系统的分析,获得了最高产量施肥量;筛选出大豆产量１２００￣１８００ｋｇ／ｈｍ＾２时,以１５０ｋｇ／ｈｍ＾２为间距的５组专用肥主要成分优化组合方案;当大豆产量≥１８００ｋｇ／ｈｍ＾２时,专用肥中主要成分最佳用量为：氮肥（Ｎ）３８．９５￣８８．２３ｋｇ／ｈｍ