Insights into the mechanism of L-malic acid on drip loss of chicken meat under commercial conditions

Background A deterioration in the meat quality of broilers has attracted much more attention in recent years.L-malic acid(MA)is evidenced to decrease meat drip loss in broilers,but the underlying molecular mechanisms are still unclear.It’s also not sure whether the outputs obtained under experimental conditions can be obtained in a com-mercial condition.Here,we investigated the effects and mechanisms of dietary MA supplementation on chicken meat drip loss at large-scale rearing.Results Results showed that the growth performance and drip loss were improved by MA supplementation.Meat metabolome revealed that L-2-aminoadipic acid,β-aminoisobutyric acid,eicosapentaenoic acid,and nicotinamide,as well as amino acid metabolism pathways connected to the improvements of meat quality by MA addition.The transcriptome analysis further indicated that the effect of MA on drip loss was also related to the proper immune response,evidenced by the enhanced B cell receptor signaling pathway,NF-κB signaling pathway,TNF signaling pathway,and IL-17 signaling pathway.Conclusions We provided evidence that MA decreased chicken meat drip loss under commercial conditions.Metabolome and transcriptome revealed a comprehensive understanding of the underlying mechanisms.Together,MA could be used as a promising dietary supplement for enhancing the water-holding capacity of chicken meat.

Effects of drip and flood irrigation on carbon dioxide exchange and crop growth in the maize ecosystem in the Hetao Irrigation District,China

Drip irrigation and flood irrigation are major irrigation methods for maize crops in the Hetao Irrigation District,Inner Mongolia Autonomous Region,China.This research delves into the effects of these irrigation methods on carbon dioxide(CO_(2))exchange and crop growth in this region.The experimental site was divided into drip and flood irrigation zones.The irrigation schedules of this study aligned with the local commonly used irrigation schedule.We employed a developed chamber system to measure the diurnal CO_(2)exchange of maize plants during various growth stages under both drip and flood irrigation methods.From May to September in 2020 and 2021,two sets of repeated experiments were conducted.In each experiment,a total of nine measurements of CO_(2)exchange were performed to obtain carbon exchange data at different growth stages of maize crop.During each CO_(2)exchange measurement event,CO_(2)flux data were collected every two hours over a day-long period to capture the diurnal variations in CO_(2)exchange.During each CO_(2)exchange measurement event,the biological parameters(aboveground biomass and crop growth rate)of maize and environmental parameters(including air humidity,air temperature,precipitation,soil water content,and photosynthetically active radiation)were measured.The results indicated a V-shaped trend in net ecosystem CO_(2)exchange in daytime,reducing slowly at night,while the net assimilation rate(net primary productivity)exhibited a contrasting trend.Notably,compared with flood irrigation,drip irrigation demonstrated significantly higher average daily soil CO_(2)emission and greater average daily CO_(2)absorption by maize plants.Consequently,within the maize ecosystem,drip irrigation appeared more conducive to absorbing atmospheric CO_(2).Furthermore,drip irrigation demonstrated a faster crop growth rate and increased aboveground biomass compared with flood irrigation.A strong linear relationship existed between leaf area index and light utilization efficiency,irrespective of the irrigation method.Notably,drip irrigation displayed superior light use efficiency compared with flood irrigation.The final yield results corroborated these findings,indicating that drip irrigation yielded higher harvest index and overall yield than flood irrigation.The results of this study provide a basis for the selection of optimal irrigation methods commonly used in the Hetao Irrigation District.This research also serves as a reference for future irrigation studies that consider measurements of both carbon emissions and yield simultaneously.

Integrated network pharmacology and metabolomics to explore the mechanisms of Shenzao dripping pill against chronic myocardial ischemia

Background:Shenzao dripping pill(SZDP)is empirically prescribed for treating cardiac diseases.Nevertheless,there is a lack of comprehensive knowledge regarding the underlying mechanisms contributing to its therapeutic effects.The objective of this study is to investigate the underlying mechanism of SZDP against chronic myocardial ischemia(CMI)in a rat model.Methods:In this study,we utilized electrocardiographic and echocardiographic detection along with pathological tissue analysis to evaluate the efficacy of SZDP.The integration of network pharmacology and metabolomics was conducted to investigate the mechanisms.Molecular docking and molecular dynamics simulations were used to validate the binding energy between the compounds of SZDP and the associated targets.Results:The results showed that SZDP was able to improve T wave voltage,reverse CMI abnormalities in ejection fraction and fractional shortening,and restore histopathological heart damage.Metabolomics results indicated that disturbances of metabolic profile in CMI rats were partly corrected after SZDP administration,mainly affecting purine metabolism.13-Docosenamide may be the potential metabolic biomarker of the therapeutic application of SZDP for CMI.Integrating network pharmacology and metabolomics,thiopurine S-methyltransferase(TPMT),xanthine dehydrogenase/oxidase(XDH),bifunctional purine biosynthesis protein ATIC(ATIC),and cytochrome p4501A1(CYP1A1)were identified as possible targets of SZDP to exert therapeutic effects by enhancing the metabolic levels of L-Tryptophan,Deoxyribose 1-phosphate and Phosphoribosyl formamidocarboxamide.Conclusion:SZDP has a therapeutic effect on CMI by regulating metabolite levels,acting on the targets of TMPT,XDH,ATIC,and CYP1A1,and reducing cardiomyocyte injury and myocardial fibrosis.

Drip fertigation and plant hedgerows significantly reduce nitrogen and phosphorus losses and maintain high fruit yields in intensive orchards

A field experiment was carried out to evaluate the effects of drip fertigation combined with plant hedgerows on nitrogen and phosphorus runoff losses in intensive pear orchards in the Tai Lake Basin.Nitrogen and phosphorus runoff over a whole year were measured by using successional runoff water collection devices.The four experimental treatments were conventional fertilization(CK),drip fertigation(DF),conventional fertilization combined with plant hedgerows(C+H),and drip fertigation combined with plant hedgerows(D+H).The results from one year of continuous monitoring showed a significant positive correlation between precipitation and surface runoff discharge.Surface runoff discharge under the treatments without plant hedgerows totaled 15.86%of precipitation,while surface runoff discharge under the treatments with plant hedgerows totaled 12.82%of precipitation.Plant hedgerows reduced the number of runoff events and the amount of surface runoff.Precipitation is the main driving force for the loss of nitrogen and phosphorus in surface runoff,and fertilization is an important factor affecting the losses of nitrogen and phosphorus.In CK,approximately 7.36%of nitrogen and 2.63%of phosphorus from fertilization entered the surface water through runoff.Drip fertigation reduced the accumulation of nitrogen and phosphorus in the surface soil and lowered the runoff loss concentrations of total nitrogen(TN)and total phosphorus(TP).Drip fertigation combined with plant hedgerows significantly reduced the overall TN and TP losses by 45.38 and 36.81%,respectively,in comparison to the CK totals.Drip fertigation increased the vertical migration depth of nitrogen and phosphorus nutrients and reduced the accumulation of nitrogen and phosphorus in the surface soil,which increased the pear yield.The promotion of drip fertigation combined with plant hedgerows will greatly reduce the losses of nitrogen and phosphorus to runoff and maintain the high fruit yields in the intensive orchards of the Tai Lake Basin.

Growth and nitrogen productivity of drip-irrigated winter wheat under different nitrogen fertigation strategies in the North China Plain

Excessive application of nitrogen (N) fertilizer is the main cause of N loss and poor use efficiency in winter wheat (Triticum aestivum L.) production in the North China Plain (NCP).Drip fertigation is considered to be an effective method for improving N use efficiency and reducing losses,while the performance of drip fertigation in winter wheat is limited by poor N scheduling.A two-year field experiment was conducted to evaluate the growth,development and yield of drip-fertigated winter wheat under different split urea (46%N,240 kg ha^(-1)) applications.The six treatments consisted of five fertigation N application scheduling programs and one slow-release fertilizer (SRF) application.The five N scheduling treatments were N0–100 (0%at sowing and 100%at jointing/booting),N25–75 (25%at sowing and 75%at jointing and booting),N50–50(50%at sowing and 50%at jointing/booting),N75–25 (75%at sowing and 25 at jointing/booting),and N100–0 (100%at sowing and 0%at jointing/booting).The SRF (43%N,240 kg ha^(-1)) was only used as fertilizer at sowing.Split N application significantly (P<0.05) affected wheat grain yield,yield components,aboveground biomass (ABM),water use efficiency(WUE) and nitrogen partial factor productivity (NPFP).The N50–50 and SRF treatments respectively had the highest yield(8.84 and 8.85 t ha^(-1)),ABM (20.67 and 20.83 t ha^(-1)),WUE (2.28 and 2.17 kg m^(-3)) and NPFP (36.82 and 36.88 kg kg^(-1)).This work provided substantial evidence that urea-N applied in equal splits between basal and topdressing doses compete economically with the highly expensive SRF for fertilization of winter wheat crops.Although the single-dose SRF could reduce labor costs involved with the traditional method of manual spreading,the drip fertigation system used in this study with the N50–50 treatment provides an option for farmers to maintain wheat production in the NCP.

Effect of fertigation frequency on soil nitrogen distribution and tomato yield under alternate partial root-zone drip irrigation

Alternate partial root-zone drip fertigation (ADF) is a combination of alternating irrigation and drip fertigation,with the potential to save water and increase nitrogen (N) fertilizer efficiency.A 2-year greenhouse experiment was conducted to evaluate the effect of different fertigation frequencies on the distribution of soil moisture and nutrients and tomato yield under ADF.The treatments included three ADF frequencies with intervals of 3 days (F3),6 days (F6) and 12 days (F12),and conventional drip fertigation as a control (CK),which was fertilized once every 6 days.For the ADF treatments,two drip tapes were placed 10 cm away on each side of the tomato row,and alternate drip irrigation was realized using a manual valve on the distribution tapes.For the CK treatment,a drip tape was located close to the roots of the tomato plants.The total N application rate of all treatments was 180 kg ha^(-1).The total irrigation amounts applied to the CK treatment were450.6 and 446.1 mm in 2019 and 2020,respectively;and the irrigation amounts applied to the ADF treatments were 60%of those of the CK treatment.The F3 treatment resulted in water and N being distributed mainly in the 0–40-cm soil layer with less water and N being distributed in the 40–60-cm soil layer.The F6 treatment led to 21.0 and 29.0%higher 2-year average concentration of mineral N in the 0–20 and 20–40-cm soil layer,respectively and a 23.0%lower N concentration in the 40–60-cm soil layer than in the CK treatment.The 2-year average tomato yields of the F3,F6,F12,and CK treatments were 107.5,102.6,87.2,and 98.7 t ha^(-1),respectively.The tomato yield of F3 was significantly higher (23.3%) than that in the F12 treatment,whereas there was no significant difference between the F3 and F6 treatment.The F6 treatment resulted in yield similar to the CK treatment,indicating that ADF could maintain tomato yield with a 40%saving in water use.Based on the distribution of water and N,and tomato yield,a fertigation frequency of 6 days under ADF should be considered as a water-saving strategy for greenhouse tomato production.

Liqi Huoxue dripping pill protects against myocardial ischemia-reperfusion injury via the PI3K/Akt/GSK-3β signaling pathway in rats

Background:Liqi Huoxue dripping pill(LQHXDP),a traditional Chinese drug for coronary heart disease,has a protective effect on the heart of rats with myocardial ischemia-reperfusion injury(MIRI)in previous studies;however,its mechanism of action remains unclear.The purpose of this study was to investigate the protective mechanism of LQHXDP on MIRI in rats and its relationship with the PI3K/Akt signaling pathway.Methods:In this study,Sprague-Dawley rats were pre-infused with LQHXDP(175 mg/kg/d)for 10 days.PI3K inhibitor LY294002(0.3 mg/kg)was intravenously injected 15 minutes before ischemia.The rat model of MIRI was established by ligating the left anterior descending coronary artery.Subsequently,cardiac hemodynamics,serum myocardial injury markers,inflammatory factors,myocardial infarct size,antioxidant indexes,myocardial histopathology,and phosphorylation levels of key proteins of PI3K/Akt signaling pathway were assessed in rats.Results:LQHXDP was found to improve cardiac hemodynamic indexes,reduce serum creatine kinase MB isoenzyme activity and cardiac troponin and heart-type fatty acid binding protein levels,lower serum interleukin-1 beta,interleukin-6 and tumour necrosis factorαlevels,reduce the myocardial infarct size and enhance the antioxidant capacity of myocardial tissue in MIRI rats.Pathological analysis revealed that LQHXDP attenuated the extent of myocardial injury and protected mitochondria from damage in MIRI rats.Immunoblot analysis revealed that LQHXDP increased the expression levels of p-Akt and p-GSK-3βin MIRI rat cardiomyocytes.PI3K inhibitor LY294002 could impair these effects of LQHXDP.Conclusion:LQHXDP attenuated myocardial injury,attenuated oxidative stress injury and reduced inflammatory response in MIRI rats,and its protective effects were mediated by activating of PI3K/Akt/GSK-3βsignaling pathway.

不同滴灌定额对玉米花后叶片光合性状及籽粒生长发育的影响

为探讨玉米应对不同滴灌定额的生理响应机制,在控制条件下开展2 a池栽试验,以2个具有耐旱性差异的玉米品种为材料,设置CK1(耐旱型品种、500 mm)、T1(耐旱型品种、350 mm)、T2(耐旱型品种、200 mm)、CK2(干旱敏感型品种、500 mm)、T3(干旱敏感型品种、350 mm)和T4(干旱敏感型品种、200 mm)6个处理,分析玉米叶片光合、叶绿素荧光、光合响应特性及籽粒灌浆特性、籽粒中激素含量、淀粉合成酶活性、产量的变化。结果显示,随滴灌定额减少玉米R3期叶片净光合速率(Pn)等4项光合参数、光系统Ⅱ最大光化学量子产量(Fv/Fm)等4项叶绿素荧光参数均呈下降趋势,气孔限制百分率(Ls)和非光化学猝灭系数(NPQ)呈增加趋势。玉米叶片表观量子效率(AQE)等10项光合响应相关参数均随滴灌定额减少而下降,CK1、T1与CK2处理光补偿点(LCP)与光饱和点(LSP)、CO_(2)补偿点(CCP)与CO_(2)饱和点(CSP)间差值范围较其他处理大。籽粒灌浆速率在开花后25 d达到峰值,T2和T4处理较CK1和CK2处理显著下降。随滴灌定额减少籽粒中细胞分裂素(CTK)、生长素(IAA)含量下降,脱落酸(ABA)含量增加。T2和T4处理籽粒中酸性蔗糖转化酶、蔗糖合酶、淀粉合成酶与腺苷二磷酸葡萄糖焦磷酸化酶活性均较CK1和CK2处理显著下降。玉米产量随滴灌定额减少而显著下降,T1处理较CK1处理仅下降3.45%~4.51%。T1处理与CK1和CK2处理在上述指标间均无显著差异。采用T1处理的玉米叶片仍能维持光合性能和光系统Ⅱ结构,增强叶片对光与CO_(2)适应能力,玉米籽粒相关激素含量和淀粉合成相关酶活性增加,有效调控了籽粒生长发育及灌浆进程,玉米产量及其构成因素均表现较佳。

Green High-yield and High-efficiency Cultivation Techniques of Integrated Management of Water and Fertilizer for Maize under Mulch Drip Irrigation

The green high-yield and high-efficiency cultivation techniques of integrated management of water and fertilizer for maize under mulch drip irrigation are described from the aspects of high yield target of maize and its component factor indexes,pre-sowing preparation,sowing,post-sowing management,field management at the seedling stage,integrated management of water and fertilizer for target yield of maize,rational application of micro-fertilizer,comprehensive prevention and control of diseases and pests,timely harvest,etc.,in order to provide a reference for agricultural technicians,maize farmers and maize industry development in northern Xinjiang.

High-yield Cultivation Techniques of Drip Irrigation under Ground Membrane for Cotton

Yuepuhu County in Xinjiang has a long history of cotton planting and is a national high-quality cotton base county.In 2002,it was appraised by the Ministry of Agriculture as the"Hometown of High-yield Cotton Production in China",with an annual cotton planting area of about 43000 ha.Traditional cotton planting has disadvantages such as waste of water resources,low water use efficiency,easy breeding of diseases and insect pests,and unfavorable ground temperature recovery at the seedling stage.In order to solve the low water use efficiency in cotton planting in Yuepuhu County,reduce the occurrence of diseases and insect pests,promote sustainable cotton production,and improve the economic benefits and local ecological benefits of cotton planting,Yuepuhu County promoted the application of the resource-saving technology drip irrigation under ground membrane cotton comprehensive cultivation technology mainly promoted by the Ministry of Agriculture.This paper mainly discusses the disadvantages of traditional cotton planting,the main technical content of drip irrigation under ground membrane technology,the problems found in the practice process and the solutions,so as make cotton growers in Yuepuhu County better understand the planting technology under plastic film,and to better promote the development of cotton industry in Yuepuhu County and the surrounding regions.

麝香黄芪复方滴丸含药血清促进骨髓间充质干细胞增殖分化

背景:骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)已被广泛用于治疗神经系统疾病,但由于血脑屏障的限制以及干细胞在受损部位存活率、分化率低,导致治疗效果有限。目的:探讨麝香黄芪复方滴丸含药血清对BMSCs增殖、迁移和向星形胶质细胞分化的影响。方法:SD雄性大鼠连续灌胃麝香黄芪复方滴丸5 d后进行腹主动脉取血,分离血清备用。采用CCK-8法检测体积分数5%,10%,20%含药血清对BMSCs增殖的影响;划痕实验观察体积分数10%含药血清对BMSCs横向迁移的影响;Transwell小室培养BMSCs,用结晶紫染色和DAPI核染色观察体积分数10%含药血清对BMSCs纵向迁移的影响;用含体积分数10%含药血清的诱导液或与星形胶质细胞共培养观察BMSCs向星形胶质细胞分化情况。结果与结论:①体积分数10%和20%含药血清在第2,3天促进细胞增殖更明显,且两种体积分数无统计学差异;②在划痕30,48 h时,10%含药血清组BMSCs迁移量显著高于对照组;③10%含药血清组BMSCs穿过Transwell小室滤过膜的数量高于对照组;④体积分数10%含药血清可能促进BMSCs向星形胶质细胞方向分化,但分化作用较弱,星形胶质细胞能进一步促进含药血清诱导BMSCs向星形胶质细胞方向分化;⑤结果表明,体积分数10%含药血清能促进BMSCs体外增殖、迁移;与星形胶质细胞共培养可能促进BMSCs向星形胶质细胞方向分化。

减氮施炭对温室膜下滴灌黄瓜土壤呼吸和氮素气态损失的影响

为降低温室蔬菜过量施氮的不利影响,明确减氮施炭条件下温室膜下滴灌黄瓜土壤呼吸和氮素气态排放特征,以不覆膜不施炭(CK)为对照,设置覆膜(M)、覆膜施炭(MB)、覆膜施炭减氮(MBN_(80%))共4个处理,对覆膜条件下减氮施炭处理对黄瓜产量、耗水量、土壤养分动态、土壤呼吸、N_(2)O排放和氨挥发的影响进行探讨。结果表明:与CK相比,M可降低温室膜下滴灌黄瓜全生育期耗水量20.95%,提高水分利用效率41.03%,降低0~20 cm表层土铵态氮48.12%,降低全生育期氨挥发32.35%、N_(2)O排放量14.34%和CO_(2)排放量12.68%(<0.05)。施炭后,与CK相比,MB可降低耗水量28.37%,提高水分利用效率55.60%,降低表层土铵态氮30.0%,提升硝态氮12.37%,有机质56.28%,降低氨挥发36.68%、N_(2)O排放18.64%,但却显著增大了CO_(2)排放4.66%(p<0.05)。同M对比,MB可在M基础上,进一步提升表层土有机质和铵态氮含量,降低氨挥发,但促进了CO_(2)排放。覆膜施炭减氮20%后,与CK相比,MBN_(80%)可增产25.47%,降低耗水量32.43%,提升水分生产率72.67%,降低表层土铵态氮56.33%,增加有机质51.72%,降低氨挥发40.48%、N_(2)O排放20.79%(p<0.05)。CK全生育期全球增温潜势(global warming potential,GWP)和活性氮排放分别为13.57 t·CO_(2)-eq·hm^(-2)和6.54 kg·hm^(-2),M可显著降低GWP(14.15%)和活性氮排放(27.37%);在M基础上施炭,将进一步降低活性氮排放,但导致GWP显著增大;而在MB基础上减氮20%,可同时显著降低GWP和活性氮排放(p<0.05)。与CK相比,MBN80%在通过施炭20 t·hm^(-2),减氮20%条件下,实现增产25.47%,降低耗水量32.43%,增加有机质51.72%,增加收入17.52%,降低活性氮排放35.32%和GWP 2.28%,也可在MB的基础上,进一步实现增产,降低氨挥发,并破解M和MB处理CO_(2)排放增大的问题(p<0.05)。研究揭示了减氮施炭条件下温室膜下滴灌黄瓜土壤呼吸和氮素气态排放特征,为实现温室蔬菜节水增产固碳减排提供理论依据和技术支撑。

“精准滴灌式”党员教育管理模式在高校学生社区中的实践运用

当前,高校要推进“一站式”学生社区综合管理工作必须紧紧围绕党建引领,将党建文化、专业学习、校园文化等内容充分融入到社区管理和活动之中,使学生社区切实成为融思想教育、行为导向、生活服务、文化熏陶为一体的“第二课堂”主阵地和学校立德树人的新高地。近年来,韶关学院积极探索“精准滴灌式”党员教育管理模式在高校学生社区的实践运用,尤其在强化党建引领、优化社区软硬件设施建设、凸显学生自我管理的主体作用与持续推进和完善制度建设等方面,为“一站式”学生社区综合管理的深入开展提供强有力的平台与保障,确保其在立德树人根本任务上发挥实效。

干旱地区水盐胁迫对水稻产量构成及稻谷品质的影响研究

针对宁夏引黄灌区传统稻田蒸发量大,盐渍化耕地占地面积广、改良问题难,土地生产力下降等问题。采用水稻滴灌旱作方式,以富源4号(96D10)作为研究对象,通过设置不同土壤水分水平(W1:高100%、W2:中80%及W3:低60%田间持水率)及盐分水平(S1:轻1.2 g/kg、S2:中3.1 g/kg及S3:重5.3 g/kg),探究不同水盐胁迫对水稻产量构成及稻谷品质的影响规律。结果表明,水盐胁迫对水稻产量及品质具有较为显著的影响,其中产量构成因素中,千粒重W3S3较W1S1下降15.89%(2021年)和15.58%(2022年),饱籽率W3S3较W1S1显著下降3.45%(2021年)和4.05%(2022年),单位产量W3S3较W1S1显著下降56.48%(2021年)和63.09%(2022年);品质方面整精米率W3S3较W1S1显著下降12.65%(2021)和13.56%(2022),垩白米率W3S3较W1S1显著上升164.71%(2021)和122.73%(2022),直链淀粉含量W3S3较W1S1显著下降5.97%(2021)和8.99%(2022),蛋白质含量W3S3较W1S1显著上升53.51%(2021)和61.82%(2022)。综合考虑,在节水目标下,采用滴灌旱作方式种植水稻,保持80%田间持水率加轻、中度盐碱化(≤4.0 g/kg)的土壤环境,可以保持较为接近充分灌溉条件下的产量构成水平和较好的稻谷品质水平。该结论可为宁夏引黄灌区盐碱地可持续利用及水稻的节水灌溉适应性研究提供理论依据。

滴灌施肥频率对烤烟生长、氮肥利用及烟叶产质量的影响

为探明滴灌施肥频率对烤烟生长、氮肥利用及烟叶产质量的影响,2018-2019年通过田间试验,以不施肥空白(CK)和当地常规处理(CF,即肥料干施+滴灌)为对照,研究低频滴灌施肥(DF1,即养分管理期1次滴灌施肥)、中频滴灌施肥(DF2,即养分管理期连续2天每天1次滴灌施肥)和高频滴灌施肥(DF3,即养分管理期连续3天每天1次滴灌施肥)对烤烟农艺性状、根系发育形态、氮肥累积量和利用效率及烟叶产质量的影响。结果表明,与CF相比,各滴灌施肥处理烟叶产量无显著差异(P<0.05),氮肥利用率有不同程度提高,烟株发育状况则因滴灌施肥频率而异。与DF1和DF2相比,DF3烟株旺长期叶面积系数分别增加了7.3%~33.3%和1.6%~28.7%,根系体积分别增加了3.9%~46.6%和21.2%~40.5%,氮素利用率分别提高了39.0%~95.0%和21.5%~34.3%,烟叶烟碱含量分别增加了17.5%~28.5%和12.5%~20.0%。与中频滴灌施肥和低频滴灌施肥相比,高频滴灌施肥有利于促进烟株生长和根系形态发育,提高氮肥利用效率和烟叶品质质量,是有效协同氮肥高效利用和烟叶产质量的滴灌施肥措施。

烯效唑处理对甘薯产量、土壤残留和后茬小麦生长的影响

在甘薯膨大初期设置叶面喷施和随水根部滴灌烯效唑的施用方式,研究烯效唑对甘薯块根产量、土壤残留和后茬小麦生长的影响.结果表明,适当的烯效唑处理能抑制甘薯地上部的生长,促进块根膨大,提高块根产量,其中叶面喷施的增产效果优于随水根部滴灌.高效液相色谱检测表明,各处理组土壤中烯效唑残留浓度均低于0.1 mg/kg,但是后茬土壤的生物效应试验显示,烯效唑有效成分施用量≥10 g/666.7 m^(2)时,土壤中的残留有可能对后茬作物产生影响.后茬小麦田间试验结果发现,随着甘薯生产中烯效唑施用期延后和剂量的增加,后茬小麦的株高和产量显著下降.因此,北方薯区春薯栽后67 d左右,进行<10 g/666.7 m^(2)烯效唑叶面喷施可以提高甘薯产量,同时对后茬小麦没有不良影响.

水氮运筹对滴灌冬小麦产量和水氮利用效率的影响

为探究水氮运筹对滴灌冬小麦产量和水氮利用效率的效应,于2019—2021年开展了连续2年小麦田间试验,设置2个施氮水平210(N1)和240(N_(2))kg·hm^(-2),4个灌水处理W1(不灌水)、W2(每次30 mm)、W_(3)(每次45 mm)、W_(4)(每次60 mm),分析不同处理小麦产量及水氮利用率相关指标。结果表明,2019—2021年,施氮量和灌水量对冬小麦抽穗期、扬花期和灌浆期叶片净光合速率的影响为极显著(P<0.01)或显著(P<0.05),且三个生育时期均以N_(2)W_(4)处理最高,与N1W_(4)和N_(2)W_(3)处理间没有显著差异;三个生育时期的土壤铵态氮和硝态氮含量均以N_(2)W_(3)、N1W_(4)或N_(2)W_(4)处理最低。小麦越冬期、灌浆期和成熟期土壤铵态氮与产量和氮肥偏生产力(NPFP)均呈显著或极显著负相关;抽穗期、灌浆期和成熟期土壤硝态氮与产量和NPFP均呈显著或极显著负相关。2个年度,水氮运筹较对照显著提高了冬小麦的产量和水氮利用效率,产量增幅分别为38.9%~62.0%和40.9%~68.3%,水分利用效率(WUE)增幅分别为8.0%~15.7%和10.1%~16.4%,NPFP增幅分别为38.9%~62.0%和40.9%~65.5%;冬小麦产量和WUE均以N_(2)W_(4)处理最高,N_(2)W_(3)处理次之,两者间没有显著性差异;但N_(2)W_(3)处理的水分利用效率均显著高于N_(2)W_(4)处理。综上,在本试验条件下,施氮量240 kg·hm^(-2)、每次灌水45 mm(N_(2)W_(3))为该地区滴灌冬小麦最佳水氮运筹组合,可以实现保障产量和提高水氮利用效率的目标。

紫花苜蓿地下滴灌灌水均匀性与适宜灌溉定额研究

研究主要探究不同灌溉方式紫花苜蓿地下滴灌灌水均匀性差距,并提出适宜的灌水定额。采用田间试验,设3个地下滴灌灌水定额(20、25、30 mm),2个埋设深度(10、20 cm)和2个滴头流量(1.38、2.0 L/h),研究了滴灌带流量、埋深在不同紫花苜蓿生育期内的灌水均匀度差异,同时进一步探究了不同灌水处理对紫花苜蓿株高、产量等参数的影响。滴灌带滴头流量对滴灌灌水均匀性的影响相对较大。在相同的滴灌带滴头流量下,滴灌带埋设深度10 cm与20 cm对滴灌灌水均匀系数影响不显著。当耗水量为456.69 mm时,紫花苜蓿干草产量最大,为12847.78 kg/hm-2。基于节水效果、产量和高效等多生产因素的综合考虑,建议鄂尔多斯鄂托克前旗地区紫花苜蓿地下滴灌灌水定额为25 mm,灌水12~14次。

中药直肠滴入联合乳果糖治疗热扰心神型肝性脑病的临床疗效及对血清内毒素、血氨和肠黏膜屏障功能的影响

目的中药直肠滴入联合乳果糖治疗热扰心神型肝性脑病(HE)的临床疗效及对血清内毒素、血氨和肠黏膜屏障功能的影响。方法选取2021年4月至2022年3月秦皇岛市第三医院收治的126例HE病人按随机数字表法分为乳果糖组、中药直肠滴入组和乳果糖联合中药直肠滴入组(联合组),每组各42例,均给予常规支持治疗后,乳果糖组采用单一乳果糖治疗,中药直肠滴入组采用单一中药直肠滴入治疗(大黄、黄连、黄芩各20g,加水800mL煎至150mL),联合组采用乳果糖联合中药直肠滴入治疗,均治疗1周,观察三组病人治疗前后血清内毒素水平、血氨水平、肝功能指标[天冬氨酸转氨酶(AST)、丙氨酸转氨酶(ALT)、总胆红素(TBil)]水平、炎症因子[肿瘤坏死因子α(TNF-α)、白细胞介素-6(IL-6)]水平、肠黏膜屏障功能[二胺氧化酶(DAO)、D-乳酸(D-LA)]水平和中医症状评分等变化情况,并评估三组病人精神状态改善时间、临床疗效和不良反应。结果三组病人精神状态改善时间联合组(5.84±0.87)d<中药直肠滴入组(6.15±1.05)d<乳果糖组(8.24±1.21)d(P<0.001);三组病人临床治疗总有效率比较联合组95.24%>中药直肠滴入组92.86%>乳果糖组73.81%(P=0.005);治疗后,三组病人血清内毒素、血氨水平、TNF-α、IL-6、DAO、D-LA、AST、ALT、TBil水平水平,面赤、谵语、惊悸、失眠多梦、口干咽燥、心烦易怒等中医症状评分比较差异有统计学意义(均P<0.001)。结论三黄汤保留灌肠联合乳果糖治疗HE型肝性脑病疗效确切,可有效调节肠道内毒素,降低血氨水平,修复肠黏膜屏障,缩短神志恢复时间,改善肝功能,降低中医症状评分,且安全性高。

餐厨沼液滴灌水盐调控对土壤环境和西兰花产量的影响

为探究和评价餐厨沼液滴灌对土壤环境和作物生长的影响,通过盆栽试验研究氮磷钾等浓度施用条件下,滴灌水盐调控不同土壤水基质势水平[-20 kPa(W)和-30 kPa(P)]和餐厨沼液比例[0%(0)、10%(1)、16.7%(2)、25%(3)和33.3%(4)]对土壤盐分、无机氮含量和西兰花生长的影响。结果表明:土壤水基质势水平对土壤盐分有显著的影响,与P相比,W降低表层土壤饱和泥浆提取液电导率(ECe)13.0%;土壤ECe随沼液比例的增加而升高,33.3%沼液处理比其他处理高23.1%~46.8%。沼液比例对土壤铵态氮含量影响显著,0%沼液处理表层铵态氮是其他处理的2.2~3.0倍;餐厨沼液灌溉会降低西兰花产量,P_(2)、P_(3)和P_(4)处理下降显著。综合评价结果表明:W与P差异不显著,沼液比例越高影响越大,P_(0)处理与W_(1)、W_(2)和P_(1)处理差异不显著,但显著高于W_(3)、W_(4)、P_(2)、P_(3)和P_(4)处理。在等浓度施用氮磷钾条件下,餐厨沼液滴灌水盐调控仍会增加土壤盐分,降低土壤铵态氮含量和西兰花产量,但在控制土壤盐分和增加餐厨沼液可施用比例方面,-20 kPa明显优于-30 kPa。