To explore the response mechanism of pepper plants during flowering and fruit setting under drought stress,the pepper variety"Soft Skin 2307"was used as the experimental material.Four different levels of drought stress were applied:a control group(CK)maintained at 75％-80％of field water capacity,mild drought(LD)at 55％-60％,moderate drought(MD)at 40％-45％,and severe drought(SD)at 30％-35％ of field water capacity.Plant height,stem diameter,photosynthetic indexes,and physiological parameters of the pepper plants were measured at 0,7,14,and 21 d after the onset of stress.The results showed that the increase in both plant height and stem diameter decreased as the severity and duration of stress increased.The stem diameter increase of MD and SD conditions exhibited a significant decline at the 14-d mark of stress,accompanied by a slight reduction in plant height at both 14 and 21 d of stress.Gradual decreases were observed in the photosynthetic indexes,namely Photo,Cond,Tr,relative chlorophyll content(SPAD),and yield,corresponding to the intensification of drought stress.The CI showed a downward trend under mild stress but displayed an upward trend at 14 and 21 d of moderate and severe stress.Peroxidase(POD)activity reached its peak on the 14th day under moderate and severe stress,followed by a subsequent decline.The malondialdehyde(MDA)content exhibited a gradual increase in the early stages of stress,which escalated significantly during the middle and late stages,directly proportional to the duration of stress.Through pot simulations,this study elucidated that pepper plants were capable of maintaining basic growth requirements under mild drought stress.The findings of this research offered valuable insights for subsequent pepper cultivation and efforts towards enhancing drought resistance.
A pot experiment was carried out to study the effects of fertilization with Bacillus velezensis on the pepper variety"Xingshu 215".Eight treatments were designed,including no fertilization,application of chemical fertilizer alone(100%,80%,50%),application of biological fertilizer alone,and combined application of chemical fertilizer(100%,80%,50%)with biological fertilizer.The effects of each treatment on pepper yield,fruit quality,and soil nutrients were investigated,and the correlations between soil nutrients and fruit quality were explored.The appropriate proportions of chemical fertilizer and biological fertilizer were determined by principal component analysis.The results showed that the combined application of chemical fertilizer with biological fertilizer significantly improved the fertility,increased available phosphorus and available potassium,alleviated the acidification,and raised the pH value of the soil.At the same time,the combination promoted the absorption of nitrogen and phosphorus by pepper roots and increased plant biomass,thereby increasing the pepper yield.The application of the biological fertilizer significantly improved the fruit quality indicators,such as vitamin C,cellulose,soluble sugar,and capsaicin,while it had no significant effect on the fruit texture.The correlation analysis showed a significantly positive correlation between soil available phosphorus and vitamin C and a negative correlation between soil available potassium and capsaicin.The results of principal component analysis showed that 80%chemical fertilizer combined with biological fertilizer achieved the best effect and could be popularized in the field production.
To investigate the bioconversion efficiency of kitchen waste and the fertilization potential of relative residues,the waste-insect conversion rate and the nutrient conversion rate of housefly larvae and black soldier fly larvae were analyzed.The sodium and chloride ion in residues,the physical and chemical properties and nutrient supply capacity of residues were also analyzed.The results indicated that the waste-insect conversion rate of housefly larvae and black soldier fly larvae was 10%.The nutrient conversion rate of housefly larvae was 12.53%-29.45%,ordered in potassium>nitrogen>organic matter>phosphorus.And that of black soldier fly larvae was 14.64%-41.94%,ordered in potassium>phosphorus>nitrogen>organic matter.The total content of N,P and K in housefly larvae and black soldier fly larvae was about 12%,the content of protein was 58.88%and 47.56%,respectively.The pH value of residues after bioconversion was close to neutral,and the total content of N,P and K was>8%,the content of organic matter was>50%,which met the conditions of organic fertilizer.Further,high content of active organic matter was detected in residues.In addition,it was suggested that potential risk of long-term or direct application should be avoid due to Na+ and Cl-in residues.The results could provide reference for thorough understanding of bioconversion technology on kitchen waste and fertilizer utilization of its residues.
This study aims to select new high-yield spring maize cultivars with high density tolerance and suitable for mechanical harvesting in Dongting Lake Plain.The field experiments were conducted to compare the yield,stress resistance,and mechanical harvesting performance of 36 new maize cultivars in the Southwestern China,with"Zhongyu 335"as the control cultivar.The results showed that the average yield of the test cultivars was 9.06 t/hm2,and 17 cultivars showed the yield increase by more than 10%compared with the control.According to the kernel moisture content,the maize cultivars were classified into three groups with high,medium,and low moisture content,respectively.The kernel moisture content at harvest ranked from 23.7%("SAU210")to 33.5%("Liang 435")in different cultivars,with the average of 27.58%.There were 25 cultivars with the kernel moisture content less than 28%at harvest,which met the requirements of mechanical harvesting.The cultivars with different kernel moisture content had significant differences in the impurity rate and kernel broken rate and insignificant differences in the disease resistance and growth period.Considering the growth period,stress resistance,yield,and mechanical harvesting performance,we suggested that"Fengyu 4","DS20101","Yayu 158",and"KD205"can be selected as high-yield spring maize cultivars with high density tolerance and suitable for mechanical harvesting in Dongting Lake Plain for demonstration and promotion.
In this study,10 microbial strains were selected to analyze their ability to produce amylase,protease,cellulase,and lipase.Based on the kitchen waste organic matter components and the functional information of microbial enzymes,a compound bacterial agent was constructed to degrade efficiently kitchen waste,and the application of kitchen waste composting was studied.The results showed that Saccharomyces cerevisiae had the highest capacity of producing amylase,and Bacillus licheniformis had the highest capacity of producing protease.Aspergillus oryzae had the highest capacity of producing cellulase,and Bacillus subtilis had the highest capacity of producing lipase.The antagonistic relationship between Brevibacillus sp.and Bacillus licheniformis was found.Five high-enzyme activity microorganisms were selected to construct four groups of compound bacteria.The results of enzyme activity showed that the F2 microbial compound bacteria composed of Azotobacter salinestris,Trichoderma viride,Bacillus licheniformis,Bacillus cereus,and Aspergillus oryzae had excellent enzyme production ability,in which the amylase was 25.0 U/mL,and the protease was 0.13 U/mL.Cellulase was 1 244 U/mL,and lipase was 4.09 U/mL.The application of compound bacterial agents during composting showed that the maximum temperature reached 67 ℃ in the F2 group,and the high-temperature period lasted for 11 d.The C/N was 18.31,and the pH value was 9.08.The seed germination rate was 103.17%.Compared with the CK group,the high-temperature period was extended for 2 d in the F2 group,and the compost reached complete maturation 6 d in advance.
Using potato dextrose agar(PDA)as selective medium,a polysaccharide-producing strain TL-8 with a yield of 1.1 g/L was obtained by re-screening of shaking flask fermentation after preliminary screening from rotton wood.Through morphological observation,molecular biology identification and phylogenetic tree construction,TL-8 was identified as Irpex lacteus.Based on initial conditions of the basic fermentation medium,its culture conditions(i.e.,fermentation time,pH value,shaking speed,and temperature)and medium components(i.e.,nitrogen source and carbon source)were optimized and screened by the single factor experiment;furthermore,the chosen parameters were subject to the orthogonal test to determine the optimal fermentation conditions of producing extracellular polysaccharide by strain TL-8.The results showed that the optimal fermentation conditions were:yeast extract 6.0 g/L+soybean residue powder 9.0 g/L(mixed nitrogen sources),glucose 28.0 g/L+lactose 12.0 g/L(mixed carbon sources),potassium dihydrogen phosphate 2.0 g/L,magnesium sulfate 1.0 g/L,ferrous chloride 0.2 g/L,pH value 6.0,shaking speed 160 r/min,liquid filling volumn 100 mL in 250 mL flask,incubation at 30℃ for 8 d,under which the yield of extracellular polysaccharide and biomass by strain TL-8 reached 5.49 and 15.78 g/L,respectively.
The effects of cadmium stress on seed germination and bud and root growth of 6 oilseed rape(Brassica napus L.)cultivars were studied.The results showed that the seed germination was delayed or inhibited by high concentration of Cd stress,which was mainly characterized by the loss of germination vigor.With the increase in Cd concentration,the germination potential,germination rate,vigor index,and germination index of different cultivars all showed a decreasing trend,and the number of days to germination showed an increasing trend.The seed germination of"Guangyuan 58","Xinduyou 800","Meiyou 88",and"Nanyou 868"was insensitive to Cd stress.With the increase in Cd concentration,the bud length,bud fresh weight,bud dry weight,root length,root fresh weight,and root dry weight decreased."Zaoshu 100"and"Fengyou 9"were inhibited obviously by Cd stress,and when Cd concentration reached 120 mg/L,almost no roots could be observed.The bud dry weight of"Nanyou 868"and the bud length,bud fresh weight,root length,root fresh weight,and root dry weight of"Meiyou 88"showed the least decreases.The results showed that"Meiyou 88"had the strongest tolerance to Cd,serving as an elite parent for the breeding of Cd-tolerant cultivars.
[Objective]In order to explore mycoviruses in Sclerotium hydrophilum(S.hydrophilum),conserve them as biological resources,provide a foundation for studying the interaction between fungi and mycoviruses,and apply mycoviruses to biocontrol,we conducted a study to detect new viruses in S.hydrophilum[HZ11]mycelia.[Method]The modified single-primer amplification technique(M-SPAT)was used to clone RNA5 and RNA8 from 10 double-stranded RNA(dsRNA)segments in S.hydrophilum[HZ11]mycelia and virus-like particles(VPLs)isolated from mycelia.The cloned products were sequenced and analyzed.[Result]dsRNA5 was 2 038 bp in length and coded for a predicted RNA-dependent RNA polymerase(RdRp).dsRNA8 was 1 809 bp in length and coded for a predicted coat protein(CP).Phylogenetic analysis indicated that the dsRNA5 protein and dsRNA8 protein were highly close to RdRps and CP of viruses in the genus Alphapartitivirus,family Partitiviridae,respectively.The 5'-untranslated regions(UTRs)of the two dsRNAs contained the conserved sequences 5'-GAA(G)T-3',5'-TTTCTA(/CG)CCTC(/A)GATAT(A)AAATA(CG)GAA-3',and 5'-AACG(A)AA(G)TC(A)TTACCTCT-3'.The 3'-UTRs of the two dsRNAs contained the conserved sequences 5'-AAAAAAA-3',5'-AAAAAAG(A)AAAAAAAAC(A)AAAA-3',and 5'-AAAAAAAAA-3'.[Conclusion]We suggested that dsRNA5 and dsRNA8 belonged to the genome of a new Alphapartitivirus.The putative new virus was designated to be S.hydrophilum virus 3(ShV3).dsRNA5 and dsRNA8,named from the S.hydrophilum isolation,correspond to dsRNA1 and dsRNA2 of ShV3,respectively.
湖南山区高速公路受地形条件制约,存在着桥隧比高、施工难度大、施工条件差的特点,尤其是山区桥梁施工,往往存在着诸多限制性因素.受施工条件、施工场地的制约,桥梁施工中易引发水土流失及次生灾害.通过对官新高速项目山区高架桥、主要涉水桥梁施工现场的调查,分析桥梁施工工艺及局限性,研究其水土流失主要发生的根源及特点,探讨相应的水土流失防治措施.
文章主要介绍了韶山灌区渠道工程的丝草打捞采用了一种自行设计、自行研发的旋转滚刀式丝草切割机,通过研制和实验后投入到灌区工程生产中,达到了安全、便捷、经济的效果,充分体现了该设备的安全性、适应性、经济性,为同类灌区渠道工程机械打捞丝草提供了一种参考思路.该设备技术获得了国家实用新型的专利发明权.
在湖南毛俊水库枢纽工程碾压混凝土大坝施工中引入了基于北斗高精度实时定位技术的智能压实系统,该施工技术能实时处理并获知压路机钢轮准确的三维位置,以数字化、图像化的方式实时记录显示压路机行进轨迹、行进速度、碾压遍数、填筑厚度等信息;并通过与核子密度仪得到的数据进行相关性分析,从而可以通过采集到的数据来实时评判不同配比和含水率(VC值)条件下混凝土的密实度变化过程和情况,这提高了施工过程中碾压填筑施工质量和效率,为施工单位提供可视化的质量管理手段,也为建设单位提供质量管理数据支撑;最后,通过现场的检测数据和系统提供的压实数据进行了对比,进一步验证了该系统的可靠性,可为类似的水利碾压混凝土坝的施工提供参考.
"中梗阻"畅通工程以建设灌区骨干工程与高标准农田项目区连接渠道为主,以必要的灌区渠道清淤疏浚为辅,力争实现"灌溉渠系全线畅通,粮食作物高产丰收"的目标."中梗阻"畅通工程打通了水源工程和田间工程,使灌区和田间形成了完整的水生态安全网络,是保障粮食安全、促进乡村振兴的具体行动.文章对此进行了探讨.
对小型水电站进行生态改造,符合国家当前对小水电绿色发展的要求.白云电站利用现有条件安装生态机组进行生态改造,提高了水能资源利用率,解决了下游河道的生态问题.文章在白云电站生态机组工程设计时,结合现有电站的接线方式对生态机组电气主接线方案进行比选,推荐的接线方案操作简单、运行可靠,提高了生态流量下泄的保证率;充分利用电站现有设备,减少了工程投资;在电气设备布置上既考虑了生态机组的独立性,又与电站现有设备布局进行了完美结合.
引水隧洞是水利工程的重要组成部分,其施工难度和施工难点也相对较多.文章结合湖南省浏阳市椒花水库工程,对引水隧洞施工中的开凿技术、排水施工技术、地下水环境保护技术、锚杆施工技术、混凝土喷射技术、衬砌施工技术、回填注浆施工技术展开了论述.旨在对类似项目工程技术起到一定参考作用.
文章根据兴义市花生宝水库的区域水文特性、地形地质条件、水工枢纽布置方案以及施工条件,设计了多种形式的水库导截流施工方法.通过对施工方案的具体运用,总结出一系列较为成熟的水库导截流施工方法,可供参考借鉴.
随着信息技术的快速发展,数字化管理已成为现代企业提高效率、降低成本以及增强竞争力的重要手段.文章旨在探讨如何加强水利勘测设计企业数字化管理工作,包括企业数字化管理的内容、现代水利勘测设计企业进行数字化管理工作的意义以及如何结合国有水利勘测设计企业的特点来实施数字化管理.
构建智慧水利工程是水利工程建设的必然趋势和必经之路.在响应水利部推进智慧水利建设的要求下,文章以数据处理和设备控制的物联网平台为重点,先从总体上介绍了物联网平台的基础功能,并以犬木塘水库工程的实际建设为例,从数据查询、数据质量、运行运维、远程操作、原始报文等多个方面初步构想了犬木塘水库工程建设物联网平台可具备的功能,并进行了相关功能的展示界面,较全面地分析和展示了物联网平台在水利工程中的应用,可为犬木塘水库工程信息化建设提供思路和支撑.
生产建设项目水土保持信息化监管是推动新时代水土保持高质量发展的必要手段和重要保障,是新时代水土保持事业的重要抓手.文章总结近年来长沙市水土保持信息化监管工作开展成效及创新实践经验,对照两办《关于加强新时代水土保持工作的意见》,分析存在的问题与不足,提出后续水土保持监管工作重点,助力长沙生态文明建设.
文章研究了联合进水口高边坡设计的稳定性,尤其针对风化软化岩体特性的影响.使用不平衡推力传递法、萨尔玛法和EMU软件,分析了五种工况(开挖、竣工、运行、水位降落和地震)下的稳定性.针对风化软化岩体饱和抗压强度低,提出了严格控制锚固力的方法,增强边坡稳定性.在地震环境中,通过考虑地震惯性力和自重产生的抗滑力平衡,采用回填混凝土策略,进一步提升稳定性.结果表明,水压和水的自重对边坡稳定性至关重要,而在地震和低水位工况下的稳定性需得到足够关注.该研究可为工程设计提供理论和技术支持.
河道底泥是河道水体的内源污染,有效确定清淤深度是底泥清淤及处理处置方案的关键依据.文章综合分析了分层法、背景值法、拐点法及底泥吸附和解吸特征法,基于河道污染底泥的理化性质,针对污染物沿程变化及垂直分布特性综合确定了污染底泥清淤深度,并就具体应用进行了探讨.
