绿色木霉L24对玉米幼苗生长的影响

采用绿色木霉L24菌株分生孢子可湿性粉剂浸种和叶面喷施两种方式处理玉米,通过对玉米幼苗的出苗率、根长、苗高、过氧化物酶含量、叶绿素含量、根系活力和丙二醛含量等形态指标和生理生化各项指标的测定,研究木霉L24菌株对玉米幼苗生长的影响。结果表明,木霉L24菌株分生孢子可湿性粉剂对玉米的出苗率、根长和苗高等均有促进作用,可有效提高玉米过氧化物酶含量、叶绿素含量和根系活力,降低丙二醛含量。     

Soil Health and Soil Fertility Assessment by the Haney Soil Health Test in an Agricultural Soil in West Tennessee

The Haney Soil Health Test (HSHT) is a recent approach to quantify soil health by focusing mostly on soil biology. It uses a new extractant (H3A) for the extraction of plant available nutrients, a new method of soil respiration measurement (24-hr CO₂ burst) using Solvita® gel system, and a new approach in determining bioavailable carbon (C) and nitrogen (N) namely water extractable organic C (WEOC) and water extractable organic N (WEON). A soil health score is calculated by combining Solvita® respiration, WEOC, and WEON data. The objective of this study was to test the feasibility of HSHT to detect the management-induced changes in soil nutrient levels and soil health in the production systems of west Tennessee. We tested soils collected from a cover crop field trial established in 2013 on a no-till corn (Zea mays L.) – soybean [Glycine max (L.) Merr.] rotation. Compared to Mehlich-1 and Mehlich-3, H3A extracted the lowest amount of soil extractable phosphorus, potassium, calcium and magnesium. Neither the soil health score nor its component parameters showed significant differences between cover crop treatments and the control. In addition, the Solvita® CO₂ data did not provide a reliable estimation of potentially mineralizable N. Overall, the HSHT did not detect differences in soil health due to cover cropping in west Tennessee. We conclude that HSHT, though a promising concept due to its focus on linking soil biology with soil fertility and soil health, may need extensive field evaluation and refinement in contrasting soils and climates across the US.     

Pulsatilla saponin A affects proliferation and radiosensitivity of breast cancer cells by regulating miR-24-3p/RNF2 expression

AIMTo investigate the effect of Pulsatilla saponin A on proliferation and radiosensitivity of breast cancer cells and its mechanism. METHODSHuman breast cancer MCF-7 cells were treated with Pulsatilla saponin A at concentrations of 0, 5, 10, 15 and 20 mg/L and transfected with microRNA-24-3p (miR-24-3p) over-expression vector or inhibitory expression vector. The proliferation and radiosensitivity of the MCF-7 cells were measured by MTT assay and colony formation assay. The miR-24-3p expression and ring finger protein 2 （RNF2） mRNA level were detected by RT-qPCR. The protein expression of RNF2 was determined by Western blot. The luciferase reporter assay was used to detect the targeting relationship between miR-24-3p and RNF2. RESULTSCompared with control group (0 mg/L), the proliferation inhibitory rate of the MCF-7 cells was significantly increased in 5, 10, 15 and 20 mg/L Pulsatilla saponin A groups (P<0.05). The survival score of the MCF-7 cells treated with Pulsatilla saponin A was significantly decreased after irradiation, and the expression of RNF2 was significantly decreased (P<0.05). miR-24-3p targeted RNF2 and negatively regulated its expression. When the MCF-7 cells were simultaneously treated with Pulsatilla saponin A and miR-24-3p, the cell survival curve significantly shifted down. Inhibition of miR-24-3p expression reversed the proliferation-inhibiting and radiation-sensitizing effects of Pulsatilla saponin A on the MCF-7 cells. CONCLUSION Pulsatilla saponin A may affect the proliferation and radiosensitivity of breast cancer cells through miR-24-3p/RNF2 signaling pathway.     

四川省的盆地、攀西地区和川西高原“24节气”气温、降水的气候特征分析

利用四川省147个县站1961～2018年的逐日平均气温和降水量资料以及1961～2018年“24节气”初日日期,统计分析盆地、攀西地区和川西高原三个区域“24节气”气温、降水以下三个方面的特征,为人们生产生活提供参考。三个特征是：“24节气”平均气温和降水量随节气变化分布特征;相邻两个节气平均气温和降水量的节气变量;“24节气”各节气58年来平均气温和降水量历史序列的线性变化趋势。     

小麦抗叶锈病基因Lr24的一个新STS标记

来源于长穗偃麦草的基因Lr24对小麦叶锈病具有很高的抗性, 本研究旨在开发用于Lr24基因分子标记辅助育种的新的分子标记。从定位于小麦3D染色体的22对SSR、EST-SSR引物中筛选出4对揭示TcLr24多态性的引物, 用468株F2抗感群体对这4对引物进一步检测, 得到1个与Lr24共分离的EST-SSR标记Xcwem17。对该标记进行测序, 并设计了STS引物。用该STS引物及已知的Lr24 SCAR引物对试验群体进行验证, 两对引物在该F2群体中均表现共分离, 且Xcwem17可在TcLr24单基因系和已知含Lr24的农家品种泰山1号中可扩增出180 bp单一条带, 感病对照及其余7个近等基因系无扩增。该EST-SSR标记可直接用于分子标记辅助选择。     

抗稻瘟病基因Pi-2(t)紧密连锁的SSR标记的筛选与应用

根据已报道的双侧连锁标记并利用已公布的水稻基因组序列信息,在广谱抗稻瘟病基因Pi-2（t)的附近找到了一个新的SSR标记,记为SRM24,估计它与Pi-2（t)间的距离大约只有0．5cM或43kb。利用该标记,成功地将Pi-2（t)从供体材料5173导入到迄今广泛使用的雄性不育保持系珍汕97B中,获得了一批携有Pi-2（t)的珍汕97B近等基因系。     

智慧图书馆24小时自助服务架构及其实现研究

[目的/意义]智慧图书馆被认为是未来图书馆发展的主导模式和最高形态,其提供的智慧服务本身具有开展自助服务的天然需求,读者在24小时"无人值守"的情况下可获取到更加高效、便捷、智能的服务.[方法/过程]从技术、经济、操作3个层面分析了智慧图书馆开展24小时自助服务的可行性,从管理系统、人员管理、读者管理、空间改造、服务创...     

爱滋病毒抗原(P_(24))检测马传染性贫血病毒的研究

本研究通过基因工程技术生产了爱滋病毒的Ｐ２４抗原,并且运用于马传贫病毒的血清学检查,与传统方法所制备的马传贫抗原对照检测军马２５２４匹以及本实验室保留的各种马传贫阳性血清２２４份。结果显示马传贫血清能够免疫沉淀爱滋病毒（ＨＩＶ）的Ｐ２４,表明它们之间有着共同的抗原决定簇,且Ｐ２４检测法检测率高,检测周期仅３～４ｈ,明显优于传统法,可用于马传贫的快迅检测。     

免耕改良退化人工草地试验

为改善退化人工草地优质牧草生长条件,对杂草、蛴螬危害引发的退化草地,进行低成本免耕改良试验.结果表明:化学除杂、全日制放牧免耕补播与常规法(耕作重播)均能改善人工种植牧草生长环境,杂草、蛴螬数量明显降低;两种免耕补播比常规法重播成本分别降低54.1%,64.3%;改良草地优质牧草覆盖度、组分、产草量均有显著提高.     

Temperature integration of Hederahelix L.: Quality aspects and growth response

Reducing energy use in greenhouses contributes to the profitability of horticulture. Important energy savings can be realized through the use of temperature integration. However, such a greenhouse heating strategy is only acceptable for commercial purposes if there are no adverse effects on plant growth and quality. During this 3-month study, Hedera helix ‘Green Ripple’ and H. helix ‘Shamrock’ were subjected to a day/night temperature regime of 20/20 °C (control) and two treatments with temperature integration over 24 h and 4 d, respectively, based on a DIF of 13.5 °C, maintaining the average temperature at the same level of the control. Temperature treatments resulted in a promotion of stem elongation. After 3 months, shoot length rose up to maximum 37.3% when temperature integration was applied. However, temperature integration reduced total dry weight and particularly root dry weight was negatively affected. In addition, assessments of relative growth rate, shoot extension rate, specific leaf area, total leaf area and pigment concentrations were performed and it was concluded that dynamic temperature regimes with longer integration periods support commercial production of English ivy.