烟蒜轮作与套作对烤烟产量及根际土壤磷组分的影响

通过大田小区试验,研究烟蒜轮作、套作对烤烟产量和土壤不同形态磷的影响.结果表明： 烟蒜轮作、套作下烤烟产量和上中等烟比例较烤烟单作显著提高,下部叶成熟期根际土壤有效磷含量分别是烤烟单作的1.3和1.7倍.不同种植方式根际和非根际土壤无机磷组分含量均以O-P和Fe-P含量最高,Ca₂-P和Al-P次之,Ca₈-P和Ca₁₀ -P含量最低.与烤烟单作和烟蒜套作处理相比,烟蒜轮作在上部叶成熟期根际土壤Ca₂-P含量最低,Ca₈-P在下部叶成熟期含量最低,Ca₁₀-P含量在中部叶成熟期最低.烟蒜轮作和套作在下部叶成熟期和中部叶成熟期根际土壤Al-P含量分别是烤烟单作的1.6和1.9倍、1.2和1.9倍.烟蒜轮作和套作根际土壤O-P含量均显著低于烤烟单作.烟蒜轮作较烟蒜套作更能活化土壤中难溶的O-P、Ca₁₀-P和高稳性有机磷,提高烤烟产量和中上等烟比例.     

作物磷素养分的动态模拟

基于养分平衡原理,分别建立了土壤有机磷与有机肥分解磷的释放、土壤有效磷吸附的动态模型,用Langmuir方程描述土壤吸附磷量与土壤溶液磷浓度的关系,建立了植株临界磷浓度与生理发育时间的关系模型,以及基于生长潜在需要和土壤水溶性磷浓度限制的作物磷素吸收动态模型.检验结果表明,模型对小麦植株含磷率的动态变化有较好的预测效果.     

湖南会同不同年龄杉木人工林土壤磷素特征

对湖南会同不同年龄(7年生、17年生、25年生)杉木人工林土壤全磷、有效磷、无机磷组分和有机磷进行了研究,结果表明:3种不同林龄杉木林土壤全磷和有效磷的含量分别在317.06—398.56 mg/kg和0.82—1.38 mg/kg之间,土壤全磷和速效磷含量均属低水平;杉木林土壤全磷含量从7年生幼龄林到25a近熟林出现先升高后降低的规律,并且17年生和25年生林分比7年生林分分别增加了19.68%、15.75%,土壤有效磷含量17年生和25年生林分比7年生林分提高了45.55%左右;土壤磷素活化系数均小于2.0%,这表明本研究区土壤全磷向速效磷转化较难,土壤中磷素的有效性较低,但该值随着林分年龄的增加而出现增大的现象;无机磷含量分别为:7年生169.50 mg/kg、17年生182.03 mg/kg、25年生175.94 mg/kg,从幼龄林到中龄林增高,中龄林以后降低;土壤中无机磷组分以O-P含量最高,其次是Fe-P,Ca-P,Al-P最少;杉木不同生长发育阶段对无机磷形态的吸收是有选择性的,幼龄林到中龄林阶段林木以吸收Al-P为主,近熟林阶段林木以吸收Fe-P和Ca-P为主;有机磷含量在全磷所占比例随林龄的变化来看,杉木生长过程中有部分的有机磷矿化为无机磷。土壤不同形态磷的相关性分析结果显示,土壤有效磷与有机磷相关系数为0.667,呈极显著相关性,是研究区杉木人工林土壤有效磷的主要来源。     

不同磷水平配施生物炭对土壤磷有效性

生物炭在提高土壤磷素有效性及促进作物生长方面具有显著作用,但其效果因土壤类型不同存在较大差异。试验以赤红壤(pH 4.91)和褐土(pH 7.24)为供试土壤,设置3种磷肥水平(0、30、90 kg P·hm^-2,分别以不施磷、低磷、高磷表示)配施稻秆生物炭(0、4%)的大豆盆栽试验,研究了不同磷水平下配施生物炭对土壤磷有效性、磷酸单酯酶活性和植株磷吸收的影响。结果表明: 不同磷水平配施生物炭显著提高了两种土壤的速效磷和全磷含量,且低磷水平添加生物炭处理速效磷增幅最大,在赤红壤和褐土的增幅分别为192.6%和237.1%。与低磷相比,赤红壤中低磷配施生物炭处理的碱性磷酸单酯酶活性显著增加78.9%,活性有机磷含量降低39.3%,同时显著促进了植株生长与磷吸收;生物炭添加显著降低了褐土活性有机磷含量,但不同处理对土壤磷酸单酯酶活性和植株生长无显著影响。土壤活性有机磷含量与速效磷含量均呈显著负相关。综上,生物炭对土壤磷有效性的作用因土壤类型和磷肥水平差异而不同,其在赤红壤上对植株生长和磷吸收的促进效应强于褐土,且在低磷条件下效果更佳。本研究为生物炭在减施磷肥和促进大豆磷吸收,特别是在赤红壤上的应用提供了科学依据。     

Evaluation of garlic intercropping for enhancing the biological control of Ralstonia solanacearum in flue-cured tobacco fields

Tobacco bacterial wilt, Ralstonia solanacearum, is an important disease affecting the root and stem. The disease causes extensive damage to flue-cured tobacco all over the word. Field trials were conducted in 2008 and 2009 at Longyan, Fujian Province, China, to evaluate garlic intercropping for enhancing the biological control of R. solanacearum in flue-cured tobacco fields. The results of the study demonstrate that tobacco bacterial wilt was clearly inhibited by intercropping garlic in 2008 and 2009. The appearance of the disease in intercropped fields was delayed for about 15 days. The total number of R. solanacearum in root system soils was significantly lower in intercropped fields than in monocultured fields in 2008. These numbers were between 138×10⁴ and 161×10⁴ cfu g^–1 dry soil in intercropped fields. The corresponding values in monocultured fields were 357×10⁴ cfu g^–1 dry soil. The monetary value of tobacco leaves was obviously higher in intercropped fields than in monocultured ones. The per cent increase in monetary values in the intercropped fields was between 14 and 34%. Consequently, intercropping tobacco with garlic might be very useful for enhancing biological control of R. solanacearum in flue-cured tobacco fields.     

Phosphorus Fractionation in Core Sediments from Haihe River Mainstream,China

Sediments from Haihe River mainstream, located in Xingjiaquan, Zhangjiazui, Tianjin, were collected and examined on the basis of P fractionation. SMT (standards, measurements and testing) procedure was adopted to investigate the changes in P concentration with depth in the core sediments collected from the different sampling sites of Haihe River mainstream. The relationships among different P fractions, such as exchangeable P (Ex-P), metal oxide bounded P (NaOH-P), organic matter and grain size, were also discussed. The results indicate that in both sites the rank order of P fractions was HCl-P > Organic P (OP) > NaOH-P > Ex-P in terms of their concentration. The Ex-P represented < 4% of the sediment total P, while the NaOH-P ranged 5–21%. The calcium bound phosphorus (HCl-P) showed considerable contribution (53–80%) to the sediment total P loads. Silt/clay sized sediments exhibited significantly higher concentrations of HCl-P and Ex-P in both sites. However, coarse-sand-sized sediments exhibited significantly higher concentrations of OP in both sites and NaOH-P in Xingjiaquan. Multivariate statistics were performed to identify the factors that influenced the sediment P.     

磷用量对烤烟根系及其与地上部关系的影响

以‘豫烟10号’为材料,研究大田生育期内不同磷肥用量对烤烟根干质量等根系指标的影响,以及根系和地上部物质分配、矿质营养积累的差异.结果表明:施磷能显著促进烤烟根系发育和干物质向地上部的分配,30 kg P2O5·hm-2处理烟株具有最大的根干质量、根体积、根系活力和最小的根冠比.烤烟根系和叶片对养分的最大积累速率依次出现在移栽后57～66 d和44～55 d,施磷不仅能促进烟株对养分的吸收,使养分最大积累速率提早出现,而且能显著促进烟株地上部的养分积累,但当施磷量超过30 kg P2O5·hm-2时,上述促进作用反而减弱.在生产上应合理施磷,以提高烟叶品质.     

不同磷营养水平对烟草叶片光合作用和光呼吸的影响(英文)

研究了不同磷营养水平(0,1/4,1/2,1,2 P)对烟草(Nicotiana rustica L.)叶片光合、光呼吸、乙醇酸合成和乙醇酸氧化酶活性的影响,结果如下; 光合强度在0～1P范围内随磷水平的提高而增高,但在2P水平中略为下降。光呼吸强度在1/4～2P范围内与光合强度有相同的变化趋势,但在磷水平为零时最高;光呼吸/光合比值亦在磷水平为零时最高,并随磷营养的增加而下降。 HPMS抑制乙醇酸氧化酶活性,乙醇酸的积累量随磷水平的变化与光呼吸有一致的趋势。 在加入FMN时,不同磷营养水平的烟草叶片中乙醇酸氧化酶的活性随磷水平的提高而下降;加入FMN对酶活性的促进作用亦随磷水平的提高而下降。 叶片无机磷、有机磷及总磷含量均随磷营养水平的提高而增加。 用不同浓度的磷酸盐溶液真空渗入在1P培养的烟草叶圆片,并在0.25,0.5,10mmol/LNaHCO_3溶液中测定光合和光呼吸,结果表明在0.25和 0.5mmol/L NaHCO_3中,光呼吸随磷浓度的增加而下降;在 10mmol/L中光呼吸完全受抑制。光合作用与磷浓度关系呈单峰曲线,随着NaHCO_3浓度的提高,其高峰位置向右移,即光合最适磷浓度增大。 根据试验结果及从化学计量学推算,认为磷营养有抑制光呼吸的作用,而光呼吸的运转则有补充叶绿体内进行光合作用所需的无机磷的功能。     

杭州湾滨海湿地不同植被类型沉积物磷形态变化特征

研究了杭州湾滨海湿地不同植被类型下0-5 cm和10-20 cm沉积物总磷(TP)、无机磷(IP)、有机磷(OP)及其形态变化特征,揭示湿地植被演替对沉积物磷形态的影响.结果表明,沉积物TP,互花米草(MC)显著高于其他植被类型.在IP中,可溶性松散态磷(Soluble and loosely bound P,SL-Pi)含量光滩(CK)最小、MC最大;还原态可溶性磷(Reductant soluble P,RS-Pi)含量芦苇(LW)和MC显著高于CK和海三棱藤草(BC);钙磷(Ca-Pi)含量CK和BC显著大于LW和MC.在OP中,活性有机磷( Labile Po,L-Po)含量最低、中等活性有机磷(Moderately labile Po,ML-Po)含量最高、非活性有机磷(Nonlabile Po,NL-Po)处于中间水平.IP是磷素的主要形态、占TP的74％ -89％,而Ca-Pi又是IP的主要形态、于湿地沉积物淤积初期通过吸附沉淀作用存留.杭州湾湿地植被自然演替过程中不同植物生物量积累和营养物质循环过程的变化导致沉积物中磷形态的差异.植被演替初期,BC显著改变0-5 cm沉积物磷形态,对10-20 cm沉积物无显著影响;植物演替后期的LW和MC促使0-5 cm沉积物有机磷快速积累、10-20 cm沉积物有机磷小幅增加,同时促进Ca-Pi向可溶性、活性态磷转变.     

亚热带不同海拔黄山松林土壤磷组分及微生物特征

磷是亚热带地区植物生长必需的养分元素之一,海拔梯度可能会改变土壤-植物-微生物系统并影响土壤磷形态及有效性。了解不同海拔土壤磷组分状况,对维持山地森林生态系统可持续发展具有重要的意义。以戴云山地区不同海拔梯度(1300m和1600 m)黄山松林为研究对象,分析了土壤磷组分、微生物群落特征和磷酸酶活性。结果显示:海拔显著影响黄山松林土壤磷组分,与海拔1300 m相比,海拔1600 m处土壤总磷含量减少了48.4%—49.8%,且各磷组分(易分解态磷、中等易分解态磷和难分解态磷)含量也显著降低,淋溶层(A层)土壤的降低程度分别为45.7%、58.6%和38.7%,淀积层(B层)为82.6%、59.9%和31.1%。海拔对土壤微生物群落特征和酶活性亦有显著影响,各类微生物群落和总微生物磷脂脂肪酸含量(PLFAs),以及磷酸双酯酶(PD)活性均表现为海拔1600 m 1300 m,但酸性磷酸单酯酶(ACP)活性呈相反的趋势。冗余分析(RDA)表明,土壤磷组分主要受有机碳(SOC)调控,且SOC与有机磷组分(Na HCO3-Po和Na OH-Po)呈显著正相关;磷酸酶和外生菌根真菌(EMF)也是影响土壤磷组分变化的重要因素。研究表明,土壤有机质含量和微生物群落结构及功能的变化可能是不同海拔黄山松林土壤磷有效性的关键调控因素。     

磷高效利用野生大麦基因型筛选及其根际土壤无机磷组分特征

通过土培盆栽试验,研究了16份野生大麦种质资源在相同供磷水平下磷素吸收利用的基因型差异,探讨磷高效野生大麦根际土壤无机磷组分特征.结果表明：拔节期和扬花期磷素干物质生产效率（CV=11.6%、12.4%）、成熟期磷素籽粒生产效率（CV=13.7%）基因型间差异较大.不同生育时期磷高效基因型IS-22-30和IS-22-25生物量、磷积累量和磷素干物质生产效率均显著高于低效基因型IS-07-07,且高效基因型的籽粒产量分别是低效基因型的3.10和3.20倍.不施磷、施磷30 mg·kg^-1条件下,不同磷素利用效率野生大麦根际土壤有效磷和水溶性磷含量均显著低于非根际土壤,且高效基因型较低效基因型根际土壤水溶性磷亏缺量更大.根际与非根际土壤无机磷组分含量为Ca₁₀-P＞O-P＞Fe-P＞Al-P＞Ca₂-P＞Ca₈-P.在拔节期和扬花期,施磷30 mg·kg^-1条件下,磷高效基因型根际土壤Ca₈-P含量显著高于低效基因型,而Ca₂-P含量显著低于低效基因型;不施磷条件下,高效基因型根际土壤Ca₂-P和Ca₈-P含量均显著高于低效基因型,且根际土壤Ca₁₀-P均减少.施磷30 mg·kg^-1条件下,根际土壤Fe-P和O-P含量均表现为高效基因型显著高于低效基因型,Al-P含量则呈现相反的趋势;不施磷条件下,高效基因型根际土壤Al-P、Fe-P和O-P含量均显著低于低效基因型.低磷胁迫下,高效基因型活化吸收Ca₂-P、Al-P的能力强于低效基因型.     

亚热带米槠天然林凋落物和根系输入变化对土壤磷组分的影响

植物残体添加和去除试验(The Detritus Input and Removal Treatments, DIRT)是研究地上凋落物以及植物根系对土壤营养物质循环过程及机制探究的一种试验设计。于2012年6月选择福建省三明森林生态系统与全球变化研究站的米槠常绿阔叶天然林,设置5种处理:对照(CT)、去除凋落物(NL)、去除根系(NR)、去除凋落物与根系(NI)、添加双倍凋落物(DL),在2018年12月对各处理不同土层(0—10cm、10—20cm)土壤磷组分及其影响因子进行研究,结果表明:(1)在0—10cm土层中DL处理总磷含量显著大于NL处理,NI处理无机磷含量最低,在10—20cm中DL处理有机磷含量显著大于其他处理;(2)DL处理活性磷(Resin-P、NaHCO₃-Pi、NaHCO₃-Po)含量在0—10cm土层中显著大于其他处理。在10—20cm土层中NR处理活性磷以及中等活性磷显著大于NL处理。残留态磷(Residual-P)含量最高,但在各处理与土层之间并没有明显差异;(3)酸性磷酸酶在0—10 cm土层不同处理间的变化...     

易分解有机碳输入量对武夷山常绿阔叶林不同土层深度土壤激发效应的影响

土壤有机碳(SOC)的矿化在碳、氮循环过程中起着极为重要的作用。易分解有机碳的输入可以通过正(负)激发效应加快(减缓)原有SOC的矿化。然而,先前的研究更多关注易分解有机碳输入量对表层(0~20 cm)土壤激发效应的影响,而较少关注其对深层(>20 cm)土壤激发效应的影响。本研究利用¹³C标记葡萄糖(99 atom%)添加试验,研究葡萄糖添加量对武夷山常绿阔叶林表层(0~20 cm)和深层(30~40 cm)土壤激发效应的影响,并通过分析微生物群落组成的变化以及土壤可利用氮含量的变化探讨土壤激发效应产生的机理。结果表明:葡萄糖的添加抑制了表层和深层SOC的矿化(P<0.05),使SOC的矿化量分别减少了26%~61%与62%~68%,呈现负的激发效应,但激发强度因葡萄糖添加量和土层深度而异。对于表层土壤,激发强度随着葡萄糖添加量的增加而增加;而对于深层土壤,激发强度对葡萄糖添加量的响应并不敏感。而且,葡萄糖的添加并未显著影响表层和深层土壤的微生物量碳氮含量和微生物群落组成(总磷脂脂肪酸含量;细菌、真菌、放线菌磷脂脂肪酸含量以及细菌真菌比)(P>0.05)。土壤激发强度并非取决于土壤微生物群落组成,而是取决于土壤中可利用氮的含量,其可以分别解释表层和深层土壤激发效应变化的90.8%与63.4%。虽然葡萄糖的添加降低了土壤可利用氮的含量,但并未造成土壤氮的固持,这表明土壤现有可利用氮仍能够满足微生物对氮的需求。因此,在土壤矿质养分充足的情况下,微生物对外源易分解有机物的优先利用可能是负激发效应产生的主要原因。     

脱臭蒜素的提取机理及其系列产品研制

论述大蒜的脱臭机理及脱臭蒜素系列产品的加工技术,并展望了其市场前景。     

磷胁迫对烤烟高亲和磷转运蛋白基因表达及磷素吸收利用的影响

为探明缺磷胁迫对烤烟磷吸收的影响机理,以烤烟品种‘豫烟10号’为材料,采用盆栽试验设置不施磷(-P)和正常供磷(+P)2个处理,分析了烟草生育后期根系和叶片中高亲和磷转运蛋白基因NtPht1;1、NtPht1;2(简称PT1、PT2)的表达差异性及其表达量与烟草磷含量、磷积累量的关系。结果表明:(1)随生育期的推进,烤烟根系和叶片的PT1基因相对表达量、PT2基因相对表达量、干物质重和磷素积累量逐渐增加,烟叶的磷含量逐渐降低,根系磷含量无明显的变化规律。(2)磷胁迫促使PT1、PT2基因的表达量上调,其中叶片PT1基因的相对表达量高于根系,叶片PT2基因的相对表达量显著低于根系。(3)磷胁迫限制了烤烟对干物质和磷素的积累,在移栽后90d,-P处理烤烟根系和叶片的干物质重、磷素积累量不到+P处理的一半,处理间差异极显著。研究认为,在缺磷环境下,烟草高亲和磷转运蛋白基因PT1和PT2表达量的增加,是由磷胁迫下烟草体内磷积累量降低所引起的系统性调控。     

不同林龄橡胶(Hevea brasiliensis)林土壤微生物群落和磷组分的变化

橡胶林是我国热带地区重要的经济林,而土壤磷是热带地区植物生长的重要限制因子之一,理解土壤磷转化机理对于生态系统的磷管理和可持续发展具有重要意义。因此,以热带地区海南儋州不同林龄(4、15、31a)橡胶人工林为研究对象,采用Hedley连续浸提法研究了土壤磷组分,磷脂脂肪酸法(Phospholipid fatty acids,PLFAs)分析了土壤微生物群落。结果表明,在橡胶林内各磷组分的相对含量大小顺序为:闭蓄态磷中等活性态磷活性态磷团聚体内磷钙磷。随着林龄的增加,橡胶林土壤中的磷组分发生显著变化。4、15、31a橡胶林的闭蓄态磷分别占总提取磷的52.61%、47.17%和34.91%,而活性态磷分别占总提取磷的6.67%、11.32%、13.68%。土壤总微生物、细菌、革兰氏阴性菌(G~-)、革兰氏阳性菌(G~+)的PLFAs含量均表现为15a4a31a,而31a橡胶林放线菌、真菌(F)和丛枝菌根真菌(AMF)的PLFAs含量均低于4a和15a。冗余分析(RDA)显示,全氮、有机碳、p H、F、AMF、G~-、G~+是引起不同林龄橡胶林土壤磷组分变化的重要贡献因子。研究表明,在橡胶林发育过程中,土壤理化性质和微生物群落发生了明显的变化,进而影响到土壤磷的转化过程。     

岩溶石漠化区不同植被恢复模式土壤无机磷形态特征及影响因素

为分析岩溶石漠化区不同植被恢复模式土壤无机磷的形态特征,评价植被恢复的土壤供磷潜力,阐明有机碳及钙素在无机磷形态转化中的作用,选取研究区内8种有代表性的样地,采用蒋柏藩无机磷分级方法对土壤无机磷形态特征及影响因素进行研究。结果表明:研究区土壤全磷与速效磷含量分别在0.25—1.35 g/kg、1.05—53.01 mg/kg范围,无机磷总量在123.94—934.61 mg/kg,耕地与退耕地以及各退耕地之间全磷、速效磷、各形态无机磷含量水平差异明显,各退耕地磷素含量水平介于耕地与次生马尾松林地之间,退耕地中桃林地、花椒林地磷素含量水平较高、樟树林地、柳杉林地、撂荒草地次之、撂荒灌丛地较低。各样地土壤无机磷占全磷比例在51.2%—72.4%,不同形态的无机磷含量表现为O-PFe-PCa-PAl-P,其中Ca2-P、Al-P对速效磷的贡献率大,Fe-P、Ca8-P贡献较小,O-P、Ca10-P献率最小。不同活性土壤有机碳与不同形态钙素对各形态无机磷在总无机磷中比例的影响较大,p H、容重、粘粒含量、含水量等其它理化性质影响较小。     

Mycorrhiza and Phosphate Solubilizing Bacteria: Potential Bioagents for Sustainable Phosphorus Management in Agriculture

Phosphorus (P) is a critical nutrient that plays an essential role in improving soil fertility for optimum plant growth and productivity. It is one of the most deficient macro-nutrients in agricultural soils after nitrogen and is considered inadequate for plant growth and production. To P availability in soils, the farmers are applying huge amounts of synthetic P fertilizers that adversely affect the wider environment, groundwater, soil fertility and microbial population. Many beneficial microbes are known to release and supply soluble P for improving growth and yield of a variety of plants in a sustainable manner in P deficient soils. Thus, inoculation of these microbes, including arbuscular mycorrhizal fungi (AMF) and phosphate solubilizing bacteria (PSB) to soil to enhance crop production without harming the environment, is an alternative approach to chemical fertilizers. The combined role of AMF and PSB in P solubilization is not well understood and the application and mode of action of these microbial groups are often naive due to variation in the environment. Therefore, the current review article would develop a better understanding of the interactive role and mechanisms of AMF and PSB in improving P availability from both organic and inorganic sources in a sustainable crop production system. Finally, the current review would loop out further avenues for researchers interested to commercially produce effective AMF and PSB-based biofertilizers for sustainable management of phosphorus over a wide range of agricultural crops worldwide.     

Development of P-Hyperaccumulator Plant Strategies to Remediate Soils with Excess P Concentrations

Dr. David Tsao, Hydrocarbon and Environmental Management Group, Global Envionmental Management Business Unit, BP Amoco Corporation, 150 W. Warrenville Rd., Mail Code H-7, Naperville, IL 60563 The U.S. livestock industry has evolved to confine a large number of animals on a few farms in concentrated areas in many states. The trend to fewer, larger operations coupled with highly intensive production methods has resulted in more concentration of manure nutrients within relatively small geographic areas. Researchers in these areas have reported that manure production is contributing more phosphorus (P) than available cropland can assimilate. Overapplication of manure nutrients combined with low P removal rates by many crops is frequently cited as a reason for the accumulation of excess soil P. We propose that higher amounts of soil P can be removed from soil using vegetative management. Soil P concentration can be reduced in fields with excess levels by using P-hyperaccumulator plants or growing plants that have been modified to increase their P-uptake characteristics through traditional breeding and transgenic techniques. In this context, we identify plant properties (root architecture, secretion of organic acids, etc.) that may be improved using these two techniques.     

Reactive oxygen species scavenging capacity of different cooked garlic preparations

It was studied if the ability of aqueous garlic extracts to scavenge superoxide anion (O(2)(*-)), hydrogen peroxide (H(2)O(2)), and hydroxyl radical (OH(*)) is altered in the following aqueous preparations: (a) extracts of boiled garlic cloves (BG), (b) extracts of microwave-treated garlic cloves (MG), and (c) extracts of pickled garlic (PG), and heated extracts of (a) garlic powder (HGP) and (b) raw garlic (HRG). The data were compared with the unheated raw garlic (RG) or with the unheated garlic powder (GP). Extracts of GP and RG scavenged O(2)(*-), H(2)O(2), and OH(*) in a concentration-dependent way. The reactive oxygen species scavenging capacity was not decreased in the aqueous garlic extracts except in MG and HRG (for O(2)(*-)) and in HGP and PG (for H(2)O(2)). The heating before or after garlic cutting was unable to eliminate the capacity of the extracts to scavenge H(2)O(2), O(2)(*-), and OH(*).