臭氧胁迫下硅对大豆抗氧化系统、生物量及产量的影响

Effect of silicon application on antioxidant system,biomass and yield of soybean under ozone pollution

在全球变化情景下,臭氧污染对作物产量将造成严重影响,臭氧将成为未来农业重要胁迫因素。研究缓解臭氧胁迫技术措施有利于保障粮食安全,其中硅元素添加可能是有效途径之一。利用开顶式同化箱(open top chambers,OTCs)装置,设置两个O3浓度(大气O3浓度<40μg/kg和高O3浓度约为80μg/kg)、两个硅浓度(0和100μg/g),研究不同O3浓度下硅对开花后大豆(Glycine max)株高、叶面积、叶绿素含量、抗氧化系统及产量的影响。结果表明:在无臭氧胁迫下,施硅可显著提高大豆根生物量、总生物量和单株籽粒重(14%、5%和20%)(P<0.05)。在O3胁迫下,施硅能使大豆维持较高的叶面积,显著提高大豆叶片叶绿素含量及SOD、POD、CAT活性,显著降低MDA含量,提高大豆根生物量、地上部生物量、总生物量、根冠比和单株籽粒重(29%,18%,19%,9%和17%)(P<0.05)。研究可为缓解O3对大豆危害提供合理可行的栽培管理措施与理论依据。

Ozone is believed to be an important environmental pollutant causing severe losses of crops production under global change scenarios.Technical countermeasures to easing ozone stress would help ensure food security,among which adding silicon might be one of the practical approaches.Open-top chambers（OTCs） were applied in determining the effects of ozone（normal air,40 μg/kg O3 or elevated O3,（80±5） μg/kg,7 h/d） and silicon（Si-free,0 mg/kg or ＋Si,100 μg/g） on plant height,leaf area,chlorophyll content,antioxidant system and yield of soybean after anthesis.Our results indicated that,under normal air condition,compared with Si-free treatments,＋Si significantly increased the amount of biomass of soybean roots,total biomass and grain weight per plant（14%,5% and 20%）（P0.05）.While under the elevated O3 environment,against Si-free treatments,silicon application could maintain a high leaf area of soybean.Use of silicon also significantly increased chlorophyll content and SOD,POD,CAT activity,while decreased MDA content.The biomass of soybean roots,shoot,root-shoot ratio and yield of per plant were further improved by 29%,18%,19%,9% and 17%,respectively（P0.05）.Our findings might provide theoretical support for the reasonable soybean cultivation and management in alleviating the damage of ozone pollution.