摘要
以玉米单交种登海662(DH662)和浚单20(XD20)为材料,以盆栽方式研究了外源亚精胺(Spd)对淹水胁迫玉米叶片光合、根系生理及产量的调控效应。结果表明,喷施亚精胺使遭受不同生育阶段淹水胁迫的DH662和XD20产量平均提高12.9%和10.8%。不同生育阶段淹水对玉米影响不同,2个品种均以苗期淹水影响较大,且Spd对其正调控效应也最好。喷施亚精胺提高了不同生育阶段淹水处理玉米叶片的净光合速率(Pn)、气孔导度(Gs)、气孔限制值(Ls)、最大光化学效率(Fv/Fm)、光量子产量(ΦPSII)和光化学猝灭系数(qP),降低了细胞间隙CO2浓度(Ci)和非光化学猝灭系数(qN)。喷施亚精胺使淹水胁迫后DH662和XD20根系的超氧化物歧化酶(SOD)活性分别较单独淹水处理高出14.5%和4.6%,过氧化氢酶(CAT)活性分别较淹水处理高出19.9%和18.2%;使DH662和XD20根系的异柠檬酸脱氢酶(IDH)和琥珀酸脱氢酶(SDH)活性增加26.1%和19.6%,但抗坏血酸过氧化物酶(APX)活性无明显增加。喷施亚精胺缓解了淹水胁迫引起的膜脂过氧化,使DH662和XD20根系活力平均增加12.9%,根系丙二醛(MDA)含量平均降低23.9%。表明叶面喷施亚精胺可有效改善玉米根系和叶片生理功能,从而降低减产幅度,但不同玉米品种及其不同生育阶段对亚精胺的调控效应存在差异。
A pot experiment with two maize varieties DH662 and XD20 was conducted to study the regulatory effects of exoge- nous spermidine on photosynthesis and physiological characteristics and yield of maize after waterlogging stress. The results showed that the average yield of DH662 and XD20 was increased by 12.9% and 10.8% after topdressing exogenous spermidine. The effect of waterlogging in different growth stages on maize was different. The treatment at seedling to jointing stage showed more influence on the two varieties. And the effects of exogenous spermidine was best at seedling to jointing stage. The topdress- ing of exogenous spermidine could improve the utilization efficiency of light energy in different growth stages, and Pn, Gs, Ls, Fv/Fm, ФPsll, qp of leaves, but reduce Ci and qN. The activities of SOD and CAT in DH662 were increased significantly by 14.5% and 19.9%, while those in XD20 were increased significantly by 4.6% and 18.2% as compared with the waterlogging treatment. And the average activity of IDH and SDH in both the two cultivars was increased by 26.1% and 19.6%, while the activity of APX was not increased significantly. The exogenous spermidine could repress the cell membrane oxidation. The average root activity in DH662 and XD20 was increased by 12.9% and MDA content was decreased by 23.9%. Therefore, the topdressing of exogenous spermidine improves the physiological functions of leaves and roots, resulting in lower yield losses caused by waterlogging, but the sensitivity of different varities and different growth stages to Spd was different.
出处
《作物学报》
CAS
CSCD
北大核心
2012年第6期1042-1050,共9页
Acta Agronomica Sinica
基金
河南省重大公益性项目(091100910100)
国家公益性行业(气象)科研专项(GYHY201006041)
国家现代农业产业技术体系建设项目(NYCYTX-02)资助
关键词
淹水胁迫
亚精胺
玉米
抗氧化酶
Waterlogging stress
Exogenous spermidine
Maize
Anti-oxidant enzymes
