Up-regulation of miR-181a attenuates releases of CSE-induced pro-inflammatory factors and expression of collagen IV,fibronectin and α-SMA in human bronchial epithelial cells

AIM: To investigate the effect and potential mechanism of microRNA-181a (miR-181a) on cigarette smoke extract (CSE)-induced the productions of pro-inflammatory factors and the expression of collagen IV, fibronectin and α-smooth muscle actin (α-SMA) in human bronchial epithelial cells (HBECs). METHODS: CSE-induced miR-181a expression was detected by RT-qPCR in the HBECs. After tansfected with miR-181a mimic, the releases of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6 and transforming growth factor-β1 (TGF-β1) were measured by ELISA, the protein expression of collagen IV, fibronectin and α-SMA was determined by Western blot. The activation of NF-κB/TGF-β1/Smad3 pathway was also evaluated by Western blot. RESULTS: CSE increased the levels of TNF-α, IL-1β, IL-6 and TGF-β1 and the expression of collagen IV, fibronectin and α-SMA, and decreased the expression of miR-181a in the HBECs (P<0.05). However, transfected with miR-181a mimic partially prevented the releases of TNF-α, IL-1β, IL-6 and TGF-β1, and inhibited the expression of collagen IV, fibronectin and α-SMA (P<0.05). Additionally, the activation of NF-κB/TGF-β1/Smad3 evoked by CSE was attenuated after transfected with miR-181a mimic. CONCLUSION: Up-regulation of miR-181a prevents the releases of CSE-induced pro-inflammatory factors and expression of collagen IV, fibronectin and α-SMA in the HBECs, and its mechanism may be related to the inhibition of NF-κB/TGF-β1/Smad3 pathway.     

马铃薯真菌病害拮抗菌株鉴定及初步应用

针对马铃薯真菌病害发生严重、多种病害混合发生、缺乏安全有效防治方法的问题，对前期筛选出的高效拮抗 菌株BA-26 进行分类鉴定，研究其胞外代谢产物的稳定性，明确防病促生作用。通过形态特征、生理生化特性鉴定以及 16S rDNA 序列分析，BA-26 菌株为解淀粉芽孢杆菌（Bacillus amyloliquefaciens），该菌株对8 种马铃薯病原真菌均表现出 较强的拮抗作用，对茄链格孢菌（Alternaria solani）、茄病镰刀菌（Fusarium solani）、燕麦镰刀菌（Fusarium avenaceum） 的抑菌率大于80%；胞外代谢产物经100 ℃处理30 min、紫外照射8 h、pH 2～10 酸碱处理、蛋白酶处理1 h 后，相对抑菌 率均维持在80% 以上；室内抑菌活性测定结果表明BA-26 滤液对茄病镰刀菌的抑制率为91.3%；盆栽试验中，每盆施用 20 mL 浓度为4.0×10⁹ cfu · mL^-1 的BA-26 发酵液使马铃薯根长、须根数、株高、叶片中叶绿素含量分别显著增加32.07%、 111.94%、48.0%、19.6%。表明解淀粉芽孢杆菌BA-26 对马铃薯真菌病害抑菌谱宽，胞外代谢产物稳定性强，有较强的防病 促生作用，具有开发为马铃薯专用生防菌剂的潜力。     

群体感应信号物质对吡咯伯克霍尔德氏菌JK-SH007在杨树内定殖的影响

为了明确杨树溃疡病生防菌吡咯伯克霍尔德氏菌JK-SH007的群体感应系统是否与其内生定殖相关，本文通过群体感应指示菌紫色杆菌CV026和液相色谱串联四级杆飞行时间质谱技术（HPLC-Q-TOF-MS）确定其群体感应信号物质种类，并利用结晶紫染色、菌体回收、GFP标记等技术，研究其群体感应信号物质对该菌株生物膜及在杨树苗内的定殖能力的影响。结果表明，菌株JK-SH007产生的群体感应信号物质为含8个碳原子酰基侧链的辛酰基-L-高丝氨酸内酯（C₈-HSL）。群体感应信号物质C₈-HSL的添加对该菌株生物膜及在杨树苗内的定殖能力有影响，并且呈现低浓度促进，较高浓度抑制的规律。C₈-HSL的添加与菌株JK-SH007生物膜的OD值和菌体量具有显著相关性，相关系数分别为0.923和0.756。当添加1.0% C₈-HSL终浓度达到5×10^{-8 g/L}时，菌株JK-SH007生物膜的形成量达到峰值。荧光显微镜镜检发现，当添加100 μL C₈-HSL时，杨树组培苗根和茎中GFP荧光标记的菌株JK-SH007的定殖数量明显较CK多。菌株JK-SH007的群体感应与其在杨树内的内生定殖能力密切相关，群体感应信号物质C₈-HSL具有增强菌株JK-SH007内生定殖的能力，同时也表明该物质有利于该菌株生防效果的发挥。     

魔芋绿色防病高效栽培技术

魔芋是高经济价值作物，种植魔芋是我国秦巴、云贵区域的特色，是山区农民增收、脱贫致富的有效途径。由于良种缺乏、种植水平不高，魔芋病害重、产量低等这些问题，导致魔芋效益并不理想。本文首先分析魔芋生长环境的需求特性、生长面临的重大病害以及适宜的种植方式；进而总结魔芋生产各环节相关种植技术要点，形成一套魔芋绿色防病高效栽培技术体系；最后从品种、防病和栽培三个角度对魔芋研究与产业发展趋势进行展望。     

东莨菪素包衣种子诱导大豆抗灰斑病研究

为研究东莨菪素（一类香豆素类植物保卫素）对大豆灰斑病的防治效果，本研究通过室内试验，盆栽试验和田间小区试验，调查了东莨菪素对大豆灰斑病的防效及促生作用。结果表明：东莨菪素对灰斑病菌有显著的抑制效果。在东莨菪素浓度为8.10 mg/L时对灰斑病的诱抗效果较好，且处理后的大豆叶片内东莨菪素含量显著上升，在田间试验中，对株高、鲜重、主根长等生理指标有促进作用，且抗病性显著增加。      

Trichoderma species associated with green mould disease of Pleurotus ostreatus and their sensitivity to prochloraz

Green mould disease causes serious economic losses in Pleurotus ostreatus crops worldwide, including in Italy, where prochloraz is the only chemical fungicide allowed to control the disease. The effectiveness of the doses 0.01, 0.05, 0.25 and 1.25 μL L⁻¹ (field dose) of prochloraz (Sponix Flow, 450 g L⁻¹), against colony growth rate and spore germination of Trichoderma pleuroti, T. pleuroticola and T. guizhouense strains on wheat straw extract agar plates were evaluated. Complete inhibition of Trichoderma pleuroti and T. pleuroticola growth was shown by the field dose of prochloraz, and also by the 0.25 μL L⁻¹ dose for T. pleuroti. Complete inhibition of spore germination occurred for all Trichoderma strains at field dose, and at 0.25 μL L⁻¹ for T. pleuroti strains. In in vivo assays, the effect of prochloraz doses 0.05, 0.25 and 1.25 μL L⁻¹ on colonization of straw substrate by T. pleuroti, T. pleuroticola and T. guizhouense inoculated at two spore densities (10² and 10⁵ spores mL⁻¹) immediately after P. ostreatus spawn was studied. Trichoderma pleuroti and T. pleuroticola were both responsible for green mould disease, whereas T. guizhouense was not pathogenic. Trichoderma pleuroti was more aggressive than T. pleuroticola. Prochloraz was effective against T. pleuroti at the field dose, and against T. pleuroticola at 0.25 and 1.25 μL L⁻¹. The study on Trichoderma × Pleurotus interaction type showed that Trichoderma species were active against the mycelial growth of P. ostreatus by competition for space and nutrients, and neither hyphal interaction nor effect by volatile or nonvolatile metabolites occurred.     

应用缩节安(DPC)调控棉花株型的定位定量效应研究

缩节安(1,1-dimethyl piperidinium chloride, DPC)是棉花生产中广泛应用的植物生长延缓剂,其调控棉花茎枝生长的定位定量效应尚缺乏系统的量化研究。本研究2013—2014年在田间条件下分别于棉花现蕾期、盛蕾期后、盛花期前、盛花期后和打顶后单次应用不同剂量的DPC,测量了DPC作用有效期内的棉花株高和主茎生长速率,探究了所有主茎节间及所有果节对DPC的响应。结果表明, DPC处理对棉花主茎节间的影响范围为N节(应用DPC时的主茎节)以下1～4个和N节以上0～6个(打顶条件下),对果枝的影响范围为N节以下1～11个和N节以上0～5个,其中N节以下果枝受影响的果节多于N节以上果枝。将盛蕾期后和盛花期前2次应用DPC的效应叠加,其影响范围几乎可以覆盖全部主茎节间(果枝始节以上)和全部果节。DPC应用剂量与其作用强度并不总存在较好的线性关系。DPC的定位定量效应除了与应用时间和剂量有关,还受到温度、降水等环境条件和棉株生物量、源库关系的影响。     

Screening oat germplasm for better adaptation to cold stress in the Southern Great Plains of the United States

Oat (Avena sativa L.) is one of the most important forage crops in the Southern Great Plains of the United States. However, it is more sensitive to cold stress than other small grains. In this study, diverse oat germplasm was evaluated for winter survival across multiple years and locations in the region. Field screening started with an observation trial of 1,861 diverse genotypes in the 2012–2013 season and was followed by four seasons of replicated trials from 2013 to 2017. Selection of good winter survivors was started in 2014–2015 season. All trials were laid out in randomized complete blocks with replications of two in 2013–2014 and 2014–2015, four in 2015–2016, and three in 2016–2017. Winter survival was scored in a 1‐to‐9 scale. Data were analysed for each year and location separately. Additive main effects and multiplicative interaction (AMMI) analysis were carried out on combined data of 35 genotypes that were commonly grown in each year and location. Highly significant (p < 0.001) variations were observed among genotypes, environments and genotype‐by‐environment interaction (GEI). The first three interaction principal components (IPCs) were highly significant (p < 0.001), explaining 96% of GEI. Broad sense heritability ranged from 46% to 93%, while heritability for all environments combined was relatively low (24.6%). At the end of the two cycles (2014/2015‐to‐2016/2017) of selection, mean winter survival was improved by more than 38% per cycle compared with the base population mean. Genotypes CIav 4390, CIav 6909 and CIav 7618 showed significantly higher winter survival than the standard checks Okay and Dallas. Genotypes CIav 4390 showed 20% and 35% improvement over the standard checks Okay and Dallas, respectively. Winter survival improvement in oat will remain a difficult task because of high GEI and low heritability. The identified superior genotypes will be used as crossing parents to transfer cold tolerance genes to other elite lines.     

内蒙古牧区现代化建设中畜牧业高质量发展对策的研究

在对内蒙古部分牧业旗（县）实地调研的基础上,总结分析以33个牧业旗（县）为代表的内蒙古牧区畜牧业发展取得的进步和存在的主要问题,系统地提出了注重产业化经营、注重规划专业化生产布局、注重草原畜牧业生产方式转变、注重良种繁育体系建设、注重调整畜群结构及繁育方式、注重农牧区饲草资源互补利用体系建设的“六注重”牧区畜牧业高质量发展建议,以期为推进内蒙古牧区现代化建设提供参考。