Damage on intestinal barrier function and microbial detoxification of deoxynivalenol:A review

Deoxynivalenol(DON)is a mycotoxin that is produced by various species of Fusarium and is ubiquitous in food and feed.At low concentrations,it can cause metabolic disorders in animals and humans and,at high concentrations,it can lead to pathological changes in the body.The impact of DON on human/animal health and animal productivity has thus attracted a great deal of attention around the world.DON causes severe damage to the intestine,including compromised intestinal barrier,mucosal damage,weakened immune function,and alterations in gut microbiota composition.These effects exacerbate intestinal infections and inflammation in livestock and poultry,posing adverse effects on overall health.Furthermore,research into biological methods for DON detoxification is a crucial avenue for future studies.This includes the utilization of adsorption,enzymatic degradation,and other biological approaches to mitigate DON's impact,offering new strategies for prevention and treatment of DON-induced diseases.Future research will focus on identifying highly efficient detoxifying microorganisms or enzymes to reduce DON levels in food and feed,thereby mitigating its risks to both animals and human health.

Identification and characterization of FpRco1 in regulating vegetative growth and pathogenicity based on T-DNA insertion in Fusarium pseudograminearum

Fusarium pseudograminearum is a devastating pathogen that causes Fusarium crown rot(FCR)in wheat and poses a significant threat to wheat production in terms of grain yield and quality.However,the mechanism by which F.pseudograminearum infects wheat remains unclear.In this study,we aimed to elucidate these mechanisms by constructing a T-DNA insertion mutant library for the highly virulent strain WZ-8A of F.pseudograminearum.By screening this mutant library,we identified nine independent mutants that displayed impaired pathogenesis in barley leaves.Among these mutants,one possessed a disruption in the gene FpRCO1 that is an ortholog of Saccharomyces cerevisiae RCO1,encoding essential component of the Rpd3S histone deacetylase complex in F.pseudograminearum.To further investigate the role of FpRCO1 in F.pseudograminearum,we employed a split-marker approach to knock out FpRCO1 in F.pseudograminearum WZ-8A.FpRCO1 deletion mutants exhibit reduced vegetative growth,conidium production,and virulence in wheat coleoptiles and barley leaves,whereas the complementary strain restores these phenotypes.Moreover,under stress conditions,the FpRCO1 deletion mutants exhibited increased sensitivity to NaCl,sorbitol,and SDS,but possessed reduced sensitivity to H_(2)O_(2)compared to these characteristics in the wild-type strain.RNA-seq analysis revealed that deletion of FpRCO1 affected gene expression(particularly the downregulation of TRI gene expression),thus resulting in significantly reduced deoxynivalenol(DON)production.In summary,our findings highlight the pivotal role of FpRCO1 in regulating vegetative growth and development,asexual reproduction,DON production,and pathogenicity of F.pseudograminearum.This study provides valuable insights into the molecular mechanisms underlying F.pseudograminearum infection in wheat and may pave the way for the development of novel strategies to combat this devastating disease.

我国小麦赤霉病流行与化学防控现状及控病降毒关键技术理论创新与应用

概述了我国小麦赤霉病发生危害现状,深入剖析了该病流行危害的原因,回顾了近年来我国小麦赤霉病化学防控历程,综述了化学防控及其抗药性发生的现状,并总结了小麦赤霉病菌抗药性检测技术的发展过程。此外,对小麦赤霉病控病降毒关键技术理论创新与应用成果进行了分析和总结,展望了小麦赤霉病精准防控的科学用药技术方案,并对其可行性和有效性进行了阐释。旨在为小麦赤霉病的精准选药、科学用药提供重要的参考数据,保障我国的粮食生产安全和食品安全,进而推动我国农业实现可持续、高质量发展。

基于气相色谱-质谱法检测禾谷镰孢菌丝胞内外的脱氧雪腐镰刀菌烯醇和15-乙酰基脱氧雪腐镰刀菌烯醇

禾谷镰孢(Fusarium graminearum)是引起小麦赤霉病的主要病原真菌,不仅会造成严重的作物减产,还会产生脱氧雪腐镰刀菌烯醇(DON)等真菌毒素污染谷物,威胁人畜健康。为探究禾谷镰孢产毒菌丝胞内外的毒素含量,本文建立了气相色谱-质谱联用法同时检测DON和15-乙酰基脱氧雪腐镰刀菌烯醇(15-ADON)。通过质谱特征扫描,DON和15-ADON均获得了较高离子化效应的离子。在单离子检测(SIM)模式下,利用m/z295、235和193离子定性分析DON,m/z 392、235和193离子定性分析15-ADON。选择其中响应强度最高的m/z 235离子定量分析DON,m/z 193离子定量分析15-ADON。利用该方法检测禾谷镰孢野生型PH-1和DON合成缺陷突变体tri5胞内外的DON和15-ADON含量,PH-1胞内的DON和15-ADON含量分别为(149.13±9.15)μg/g和(1833.31±185.33)μg/g,胞外含量分别为(5910.35±468.23)μg/g和(45222.12±2726.81)μg/g;tri5突变体的胞内外均未检测到DON和15-ADON。该方法可用于菌丝胞内外DON和15-ADON的同时分析。

高温胁迫对禾谷镰孢生长和致病力的影响

为探究高温胁迫对禾谷镰孢生长和致病力的影响,本研究测定了禾谷镰孢5株耐高温菌株和4株温度敏感型菌株在25℃和30℃下的菌丝生长速率、产孢量、孢子萌发率以及不同胁迫压力下的生长速率、致病力和DON毒素含量等。结果表明,不论耐高温菌株还是温度敏感型菌株,30℃高温对其菌丝生长均有抑制作用,但对产孢量和孢子萌发有促进作用;30℃高温能减轻NaCl和CaCl2胁迫对禾谷镰孢生长的抑制,但是不影响KCl、刚果红,SDS和H2O2对病原菌的抑制作用;在30℃下,大部分耐高温菌株的致病力不变或降低,而大部分温度敏感型菌株的致病力反而增加,30℃对大部分菌株的DON毒素产量有一定促进作用。研究结果可为研究气候变化下小麦赤霉病的流行和预测提供理论基础。

家禽饲料中主要霉菌毒素含量与家禽肉、内脏、鸡蛋霉菌毒素含量的相关性分析

试验旨在研究家禽饲料中的主要霉菌毒素与家禽肉、内脏和鸡蛋霉菌毒素含量的相关性。本试验对山东省各地市分别取有代表性的16个肉鸡养殖场(每场采集饲料1份和3只肉鸡的胸肉、腿肉、心脏、肝脏)和14个蛋鸡养殖场(每场采集4枚鸡蛋和1份饲料)进行霉菌毒素检测。结果表明:肉鸡配合饲料中黄曲霉毒素B1(AFB1)、玉米赤酶烯酮(ZEN)和脱氧血腐镰刀菌烯醇(DON)的检出率分别为93.75%、100%和87.5%,1份AFB1超标饲料中含量为15.02μg/kg时,肉鸡肝脏中AFB1毒素残留量仅为0.012μg/kg。肉鸡饲料中ZEN为502、558、672.5μg/kg时,肝脏ZEN含量分别为0.25、0.354、0.405μg/kg,在其他组织中未发现ZEN毒素残留。肉鸡饲料AFB1、ZEN和DON不超标,肌肉和脏器中没有检出AFB1、ZEN和DON。蛋鸡配合饲料AFB1、ZEN和DON的检出率分别为100%、100%和93.75%,且含量均低于限量标准,3种毒素在鸡蛋中均未检出。饲料中AFB1、ZEN和DON含量低于限量标准时,在肌肉、脏器和鸡蛋中未能检出。饲料中AFB1、ZEN含量高于限量标准,肝脏可检出AFB1、ZEN。肝脏是毒素的主要存留器官,肝脏ZEN含量与饲料中ZEN含量呈显著相关性(R2=0.8558)。由以上结果可知,肉鸡饲料AFB1、ZEN含量超标,肝脏可检出相关毒素,其他脏器未检出;肝脏ZEN含量与饲料中ZEN含量呈显著相关性;饲料中AFB1、ZEN和DON含量低于限量标准时,3种毒素在肌肉、脏器和鸡蛋中未能检出。

一种鸡粪来源溶解有机氮在天然海水中不同降解阶段生物可利用性及其组分结构特征

陆源溶解有机氮(DON)是近海环境中的重要氮来源,对海洋生态系统的影响与自身生物可利用性、组分和结构有关。如何表征DON在天然海水老化过程中不断变化的生物可利用性及其结构特征是难点。以畜禽养殖鸡粪作为DON来源,通过1年的天然海水自然降解实验,测定和表征了不同降解阶段DON的理化参数和光谱特征。结果表明,按培养时间划分的生物可利用组分(BDON)中,易利用组分(LBDON,0~12 d)、半易利用组分(HLBDON,12~80 d)和难利用组分(RBDON,80~365 d)占比分别为51.41%、31.79%和2.63%。其中,LBDON和HLBDON主要是三维荧光色氨酸T组分和土壤富里酸D组分,结构上主要是胺基官能团;RBDON主要是可见光富里酸C1组分,主要包括胺基、羟基、芳基和羧基/酯基等官能团;而惰性组分(RDON)主要是三维荧光紫外区富里酸A组分和类腐殖酸E组分,结构上主要包括炔基、芳基和羧基/酯基等。RDON较BDON在芳香性、疏水性和腐殖化指数上均显著升高,分别升高了89.8%、86.5%和39.2%。研究结果有助于深入理解海洋中陆源DON的生物可利用性及其生态效应。

禾谷镰刀菌异质核糖核蛋白FGSG_07478功能研究

[目的]异质核糖核蛋白(heterogeneous nuclear ribonucleoproteins,hnRNP)是一类RNA结合蛋白,在RNA代谢的各个方面发挥着重要作用。将目前已注释的镰刀菌hnRNP G在禾谷镰刀菌基因组中进行比对,得到其同源蛋白FGSG_07478。本研究旨在考察该蛋白在禾谷镰刀菌生长发育、抵抗逆境、产毒和致病等方面的作用。[方法]基于同源重组原理和聚乙二醇(PEG)介导的原生质体转化方法,获得FGSG_07478基因敲除突变体ΔFGSG_07478,观察测定其在营养生长、无性繁殖、有性生殖、抵抗逆境中的变化,同时进行小麦胚芽鞘接种试验验证其致病力。通过超高效液相色谱-串联质谱(UPLC-MS/MS)检测ΔFGSG_07478产生脱氧雪腐镰刀菌烯醇(DON)的能力,并利用RT-qPCR检测野生型菌株PH-1和突变菌株ΔFGSG_07478中参与DON生物合成的7个TRI基因的相对表达量。[结果]突变菌株ΔFGSG_07478的生长速率较野生型菌株PH-1慢16.2%,产孢量降低43.4%;有性生殖诱导结果显示ΔFGSG_07478的有性生殖能力减弱,较野生型产生更少的子囊壳。胁迫因子敏感性测定结果显示,ΔFGSG_07478对H_(2)O_(2)和十二烷基硫酸钠(SDS)等胁迫因子的敏感性显著增加,对刚果红的抗性显著增加。此外,与野生型相比,虽然致病力无明显差异,ΔFGSG_07478的DON生物合成量显著减少,TRI4、TRI5、TRI6、TRI8、TRI10、TRI12和TRI101等基因表达水平显著降低。[结论]FGSG_07478在禾谷镰刀菌的生长发育、有性生殖、逆境胁迫以及产毒过程中发挥着重要作用。

Comparative Study on the Effect of Different Fertilizers on the Growth and Development of Halenia ellipitica D.Don

[Objective] The aim was to study the effect of different treatments on development and growth of Halenia ellipitica D.Don.[Method] Three treatments (urea treatment group, diammonium phosphate treatment group and control group) were set in the experiment with 3 replications to detect plant height,root length, leaf number, branch number, flower number and biomass of Halenia ellipitica D.Don. in all experimental groups.[Result] The leaf number,branch number, flower number and output of crude drug of Halenia ellipitica D.Don. in urea treatment group were more than that of Halenia ellipitica D.Don. in diammonium phosphate treatment group and control group,however,the plant height and root length were not significantly different among all groups.[Conclusion] The urea generated better effect on Halenia ellipitica D.Don. cultivation than that produced by diammonium phosphate treatment.

禾谷镰孢的致病机制及其与小麦的分子互作

由禾谷镰孢(Fusarium graminearum)引起的小麦赤霉病作为小麦上重要的真菌病害之一,其能够产生脱氧雪腐镰刀菌烯醇(deoxynivalenol,DON)等真菌毒素,不仅影响小麦的品质,造成小麦严重减产,还严重威胁人畜健康。研究表明,在禾谷镰孢侵染小麦早期,效应蛋白以及DON毒素发挥着重要作用。综述总结了禾谷镰孢的致病机制、与小麦互作过程中效应蛋白和DON毒素的分子作用机制等方面的研究进展,并对未来致病基因的有效利用进行了展望,以期为今后禾谷镰孢-小麦的互作机制研究以及小麦赤霉病的防治提供理论参考。

植物免疫激活蛋白维大力在宿州市小麦生产上的应用初探

本文探索了植物免疫激活蛋白维大力在小麦抗病增产中的功效。结果表明,在小麦抽穗扬花期使用48%氰烯•戊唑醇+维大力防治2次,对小麦赤霉病具有良好的防治效果,病指防效达90%以上,对小麦DON毒素具有良好的降解作用,对小麦也具有一定的增产效应,建议在小麦生产中推广使用维大力。

臭氧/金属负载活性炭对溶解性有机氮(DON)去除效果研究

为探讨臭氧/金属改性活性炭对二级出水中溶解性有机氮(DON)的去除效果,利用SEM、XRD和BET对改性活性炭进行了表征,并结合三维荧光光谱和区域体积积分分析手段对DON进行了定量分析。结果表明:金属负载改性活性炭后,Fe-AC表面主要为Fe3O4、Cu-AC表面主要为Cu O和Cu、Mn-AC表面主要为MnO、Pd-AC和Pt-AC表面主要为Pd单质和Pt单质;相比于改性前,Fe-AC的比表面积和微孔比表面积都有一定程度的增加。经过金属负载改性的活性炭在一定程度上提高了DON的去除率,特别是Pd-AC,对DON的去除效果最佳,由改性前的56.1%提高至79.2%,增加了23.1个百分点。二级出水区域Ⅱ和Ⅳ荧光区域标准体积占总的荧光区域标准体积的63.76%,经过臭氧/金属负载活性炭处理后,区域Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ和总荧光区域标准体积呈下降趋势,荧光区域Ⅳ代表的SMPs去除率最高。

Dissolved organic carbon and nitrogen in precipitation, throughfall and stemflow from Schima superba and Cunninghamia lanceolata plantations in subtropical China

Despite growing attention to the role of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) in forest nutrient cycling, their monthly concentration dynamics in forest ecosystems, especially in subtropical forests only were little known. The goal of this study is to measure the concentrations and monthly dynamics of DOC and DON in precipitation, throughfall and stemflow for two planta- tions of Schima superba (SS) and Chinese fir (Cunninghamia lanceolata, CF) in Jianou, Fujian, China. Samples of precipitation, throughfall and stemflow were collected on a rain event base from January 2002 to December 2002. Upon collection, all water samples were analyzed for DOC, NO3 -N, NH4 -N and total dissolved N (TDN). DON was calculated by subtracting NO3 -N and NH4 -N from TDN. The results - + - + showed that the precipitation had a mean DOC concentration of 1.7 mg·L-1 and DON concentration of 0.13 mg·L-1. The mean DOC and DON concentrations in throughfall were 11.2 and 0.24 mg·L-1 in the SS and 10.3 and 0.19 mg·L-1 in the CF respectively. Stemflow DOC and DON concentrations in the CF (19.1 and 0.66 mg·L-1 respectively) were significantly higher than those in the SS (17.6 and 0.48 mg·L-1 respectively). No clear monthly variation in precipitation DOC concentration was found in our study, while DON concentration in precipita- tion tended to be higher in summer or autumn. The monthly variations of DON concentrations were very similar in throughfall and stemflow at both forests, showing an increase at the beginning of the rainy season in March. In contrast, monthly changes of the DOC concentrations in throughfall of the SS and CF were different to those in stemflow. Throughfall DOC concentrations were higher from February to April, while relatively higher DOC concentrations in stemflow were found during September-November period.

Isolation,purification,structural characteristic and antioxidative property of polysaccharides from A.cepa L.var.agrogatum Don

Allium cepa L.var.agrogatum Don(ALAP)is commonly consumed in China as well as other regions and has various beneficial health effects.A novel acidic polysaccharide(named ALAP-21)was obtained from ALAP by ultrasonic and microwave-assisted extraction and purification using DEAE-52 anion exchange and Sephadex G-100 columns.The monosaccharide composition,structural and antioxidative properties of ALAP-21 were investigated by GC–MS chromatography,FT-IR and NMR spectroscopies and three antioxidative activity tests in vitro.The results showed that ALAP-21 was a heteropolysaccharide composed of glucose,galacturonic acid,mannose,galactose,arabinose,rhamnose,xylose,fructose and glucuronic acid with a relative molar ratio of 26.282:27.546:11.400:4.781:2.467:2.445:3.622:1.106:1.753,owning(1→4)-β-d-Glcp,(1→4)-β-d-GalAp6Me3OA,(1→4)-β-d-Galp6OMe,(1→2)-β-l-Rhap,(1→4)-β-d-Manp glycosidic linkages.(1→4)-β-d-Glcp and(1→4)-β-d-GalAp6Me3OA residues might be the main components of the sugar chain backbone of ALAP-21.Furthermore,ALAP-21 exhibited high potential for DPPH radicals(82.02%),hydroxyl radicals(53.33%)and superoxide anion radicals(50.28%).These results provide a reference for further research and rational development of ALAP polysaccharides.

Functional characterization of the catalytic and bromodomain of FgGCN5 in development,DON production and virulence of Fusarium graminearum

FgGCN5,a GCN5 homolog in Fusarium graminearum,plays a critical role in hyphal vegetative growth,asexual and sexual reproduction,deoxynivalenol(DON)biosynthesis and plant infection.For nuclear localized GCN5,four conserved sequence motifs(I-IV)are presented in the catalytic domain and a bromodomain in the carboxy-terminus.As a lysine acetyltransferase,conserved negatively charged residues are present to neutralize the protons from lysine substrates.However,the role of conserved motifs/domains and residues in FgGCN5 are unclear.Here,we generated deletion mutant strains for each the conserved motifs/domains and a glutamate residue 130(E130)replacement mutant.Deletion of each conserved motif in the catalytic domain and replacement of E130 site resulted in manifold defects in hyphae growth,asexual and sexual development,DON biosynthesis,and plant infection.Phenotypic defects in the mutant strains were similar to deletion mutants.The deletion of the bromodomain led a significant reduction in DON production and virulence,with no effects on hyphae growth,asexual or sexual reproduction.FgGCN5 was further found to localize to the nucleus in conidia and hyphae cells.In conclusion,FgGCN5 encodes a nuclear localized acetyltransferase.The conserved motifs in the catalytic domain and E130 are essential for correct functions of the gene.The conserved bromodomain is impotant for DON production and pathogen virulence.This was the first report to identify the functions of conserved motifs/domains in FgGCN5,which will contribute to our understanding of the mechanism(s)by which FgGCN5 regulates F.graminearum.

Aflatoxin B1, zearalenone and deoxynivalenol in feed ingredients and complete feed from different Province in China

Background： The current study was carried out to provide a reference for monitory of aflatoxin B_1（AFB_1）,zearalenone（ZEN） and deoxynivalenol（DON） contamination in feed ingredients and complete feeds were collected from different Province in China from 2013 to 2015.Methods： A total of 443 feed ingredients, including 220 corn, 24 wheat, 24 domestic distillers dried grains with soluble（DDGS）, 55 bran, 20 wheat shorts and red dog, 37 imported DDGS, 34 corn germ meal and 29 soybean meal as well as 127 complete feeds including 25 pig complete feed（powder）, 90 pig complete feed（pellet）, six duck complete feed and six cattle complete feed were randomly collected from different Province in China,respectively, by high-performance chromatography in combined with UV or fluorescence analysis.Results： The incidence rates of AFB_1, ZEN and DON contamination of feed ingredients and complete feeds were80.8, 92.3 and 93.9 %, respectively. The percentage of positive samples for DON ranged from 66.7 to 100 %.Domestic DDGS and imported DDGS presented the most serious contamination AFB_1, ZEN and DON contamination levels of feeds ranged from 61.5 to 100 %, indicated that serious contamination over the studied 3-year period.Conclusion： The current data provide clear evidence that AFB_1, ZEN and DON contamination of feed ingredients and complete feeds in different Province in China is serious and differs over past 3-year. The use of corn, domestic DDGS, imported DDGS and corn germ meal, which may be contaminated with these three mycotoxins, as animal feed may triggered a health risk for animal. Feeds are most contaminated with DON followed by ZEN and AFB_1.Mycotoxins contamination in feed ingredients and complete feeds should be monitored routinely in China.

Breeding for FHB Resistance via Fusarium Damaged Kernels and Deoxynivalenol Accumulation as Well as Inoculation Methods in Winter Wheat

FHB is one of the most destructive diseases of wheat. Resistance testing depends strongly on inoculation methods, and on measured traits. Therefore a four-year (2009-2012) study was performed using spray inoculation + polyethylene (PE) bag cover, spray inoculation + mist irrigation, and spawn method supported by mist irrigation on 40 genotypes, 20 from Hungary and 20 from IFA Tulln, Austria. Each year four isolates were used in artificial inoculations except the spawn method where stalk debris served the inoculum. Visual Fusarium head blight (FHB) scores, Fusarium damaged kernels (FDK) and deoxynivalenol (DON) contamination were checked. 7680 FHB and FDK, as well as 3840 DON analyses served as the background for the statistical evaluation. The most reliable method used was the spray + polyethylene (PE) bag;the other two were significantly poorer being valid for all traits. The FHB scores were the least reliable, whereas the FDK was much more consequent and the DON gave the best results. The FDK gave much better predictions for DON contamination than FHB. The cultivars responses correlated well at different epidemic severities. The presence of the kernel resistance was confirmed and a new trait as extra kernel susceptibility was described. Presence of DON resistance was confirmed again, and extra DON susceptibility was described as a new trait. DON performance varied on the most sensitive cultivar between 0.32 and 143 mg/kg (mean 17.52 mg/kg) and on the most resistant genotype between 0.00 and 18.19 mg/kg (mean 1.87 mg/kg). Correlations between stability and resistance level are r = 0.85 for FHB, 0.78 for FDK, and 0.88 for DON, all at a significance level of p = 0.001. The very close correlation between FDK and DON contamination (r = 0.81, p = 0.001) proves that control of DON contamination needs appropriate resistance. In the breeding program evaluation of FDK is the most important, and then DON will be decided. Variety registration must be updated;otherwise no improvement on the field will occur.

Effects of Nitrogen Sources and Concentrations on the Growth of Different Phytoplankton Taxa

Effects of different nitrogen(N)compounds and concentrations on the growth of the three different phytoplankton taxa,Skeletonema costatum(Bacillariophyceae),Prorocentrum micans(Dinophyceae),and Chattonella marina(Raphidophyceae),were investigated.The Monod equation was applied to examine effects of N concentrations on the growth of algal cells.Results showed that nitrate(NO_(3)-N)and urea served as good N sources for the three phytoplankton taxa.S.costatum grew well on all of the seven N sources.C.marina can effectively use the two amino acids,glycine(Gly)and serine(Ser),however cannot utilize alanine(Ala),threonine(Thr),and asparaginic acid(Asp).P.micans cannot grow in five amino acid substrates.All of the three phytoplankton taxa grew well under different proportions of urea-N,and C.marina grew significantly better in medium with both NO_(3)-and urea-N.The values of maximum growth rate(μmax)and half-saturation nutrient concentration(KS)for NO_(3)-N were 0.71 divisions d−1 and 53.55μmolL^(−1) for S.costatum,0.67 divisions d−1 and 23.31μmolL^(−1) for P.micans,and 0.23 divisionsd−1 and 17.57μmolL^(−1) for C.marina,respectively.The results suggested that S.costatum had a high N demand for growth,and was capable of using wide ranges of N compounds.The strategy of N utilization for S.costatum may make this species an advantage in N-enriched sea areas especially the dissolved organic nitrogen(DON)rich coastal waters,which might be the reason why S.costatum widely distributes in the cosmo-politan coastal and estuarine sea areas.

Influences of ascorbic acid and gibberellic acid in alleviating effects of salinity in Petunia under in vitro

Salinity is one of the abiotic stresses that limits the growth and productivity of many crops.A possible survival strategy for plant under saline conditions is to use compounds that could minimize the harmful effects of salt stress on the plant development.The objective of the presented study was to investigate the effect of exogenous ascorbic acid(ASA)with or without gibberellic acid(GA3)on key growth and biochemical parameters in two petunia cultivars‘Prism Rose’and‘Prism White’under saline(150 mM NaCl)and non-saline in vitro condition.Nodal cutting with an axillary buds were used as explants.Application of 1 mM ascorbic acid with or without 0.05 mM gibberellic acid into the MS medium stimulated the length of shoots and the number of new shoots of‘Prism Rose’;whereas,it decreased the root length and the number of roots of both‘Prism Rose’and‘Prism White’under non-saline condition.The addition of ascorbic acid with or without gibberellic acid into the MS medium under saline condition,increased the length of plants and the number of new shoots,but did not affect their root number and length.NaCl treatments increased the proline content and lipid peroxidation which was indicated by the accumulation of malondialdehyde(MDA).The study revealed a correlation between chlorophylls a and b content and the leaf pigmentation intensity–parameter a*.Addition of 1 mM ascorbic acid with 0.05 mM gibberellic acid into the MS medium plays a protective role in salinity tolerance by improving the shoot growth and the development as well as increasing the activities of the antioxidant enzymes and other antioxidant substances.

Extraction Process and Content Determination of Caffeic Acid in Laggera alata from Different Production Areas of Guangxi

[Objectives] To establish a method for determining the content of Laggera alata( D. Don) Sch. Bip. Ex Oliv. using caffeic acid the target component,and to compare the content of caffeic acid in the medicinal materials of L. alata in different production areas of Guangxi.[Methods]The content was determined by Inertsil~ODS-3 chromatographic column C_(18)( 4. 60 mm × 250 mm,5 μm,mobile phase: acetonitrile-0. 1% phosphoric acid( 22∶ 78),detection wavelength: 320 nm,flow rate: 1. 0 m L/min,column temperature: 30℃,and injection volume: 10 μL. [Results] The caffeic acid showed a good linear relationship in the range of injection volume of 0. 025 92-0. 259 2 μg( R =0. 999 5). The average recovery rate was 98. 33%( RSD = 1. 85%). L. alata in different production areas of Guangxi contained the caffeic acid,and there was a great difference in the caffeic acid. L. alata in Baise had the highest content of caffeic acid,while that in Guilin had the lowest content of caffeic acid. [Conclusions]This method can accurately determine the content of caffeic acid and is expected provide a scientific basis for the development and utilization of herbal medicine L. alata.