美丽箬竹和菲白竹根系呼吸与抗氧化系统对水淹的响应

Response of Root Respiratory and Antioxidant Systems of Indocalamus decorus and Arundinaria fortunei to Flooding

为了研究水淹胁迫及恢复处理对地被竹根系抗氧化防御和无氧呼吸代谢的响应特征及适应机制,选用美丽箬竹和菲白竹为材料,采用模拟水淹胁迫和解除胁迫恢复正常,分别处理7 d和14 d,测定抗氧化酶活性、无氧呼吸酶活性和可溶性糖含量。结果表明,随着水淹时间的延长,菲白竹和美丽箬竹的丙二醛(MDA)含量和相对电导率均呈上升趋势,菲白竹水淹7 d与对照相比分别增加30.1%和21.9%(P<0.05),美丽箬竹与对照相比分别增加49.1%和15.5%(P<0.05);菲白竹超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)呈升高的趋势,水淹7d与对照相比分别增加了93.2%、60.9%和138.9%(P<0.05),美丽箬竹与对照相比降低。菲白竹和美丽箬竹可溶性糖含量呈升高的趋势,水淹7 d与对照相比分别增加116.7%和48.2%(P<0.05);菲白竹和美丽箬竹根系活力呈下降的趋势,水淹14 d与对照相比分别减少14.1%和27.9%(P<0.05);菲白竹和美丽箬竹无氧呼吸酶中丙酮脱羧酶(PDC)和乙醇脱氢酶(ADH)活性呈先升高后降低的趋势。在恢复处理7 d后,各项指标与对照无显著差异。说明菲白竹和美丽箬竹通过提高抗氧化酶活性消除活性氧,减少膜脂过氧化产物MDA含量,降低相对电导率,提高无氧呼吸酶活性和可溶性糖含量促进呼吸代谢来适应水淹逆境,在恢复7 d时各项指标都恢复正常。2个竹种相比,菲白竹具有更强的耐水淹性和恢复能力。

In order to study the response characteristics and adaptation mechanism of the antioxidant defense and anaerobic respiration metabolism of ground cover bamboo roots to waterlogging stress and recovery treatment,in this study,Indocalamus decorus and Arundinaria fortunei were selected as materials.Using simulated flooding stress and lifting stress to return to normal,the treatment was conducted for 7 days and 14 days,respectively,and the antioxidant enzyme activity,anaerobic respiration enzyme activity and soluble sugar content were determined.The results showed that with the extension of flooding time,the malondialdehyde(MDA)content and relative conductivity of A.fortunei and I.decorus increased.In comparison with the control,after 7 d of drowning they increased respectively by 30.1%and 22.0%(P<0.05)for A.fortunei,and by 49.1%and 15.5%(P<0.05)for I.decorus.The dismutase(SOD),peroxidase(POD)and catalase(CAT)of A.fortunei under the 7 d drowning increased by 93.2%,60.9%and 138.9%(P<0.05),while that of I.decorus decreased(P<0.05).Meanwhile,the soluble sugar content of A.fortunei and I.decorus increased by 116.7%and 48.2%(P<0.05).The root vitality of A.fortunei and I.decorus under 14 d drowning decreased by 14.1%and 27.9%(P<0.05).The activities of acetone decarboxylase(PDC)and alcohol dehydrogenase(ADH)in anaerobic respiration enzymes of A.fortunei and I.decorus increased first and then decreased.After 7 days of recovery,there was no significant difference between the treatment and the control.Thus,A.fortunei and I.decorus may adapt to flooding adversity by increasing antioxidant enzyme activity to eliminate active oxygen,reducing MDA content of membrane lipid peroxidation products,reducing relative conductivity,increasing anaerobic respiration enzyme activity and enhancing soluble sugar content to promote respiratory,all indicators returned to normal after 7 days of recovery.Between the two bamboo species,A.fortunei has stronger resistance to flooding and recovery.