Physiological Reaction Differences of Different Waterlogging-Tolerant Genotype Rapeseed (Brassica napus L.) to Anoxia

【Objective】The present study’s objextive was to elucidate the physiological reaction variants of different waterlogging-tolerant genotypes rapeseed(Brassica napus L.) to anoxia.【Method】Using different rapeseed genotypes as materials,the germinated seeds and three leaves stage seedlings were treated with anoxia to investigate germination characteristics,content of soluble sugar and proline,relative electrical conductance,malnodialdehyde(MDA),activities of peroxidase(POD),superoxide dismutase(SOD) and catalase(CAT) were detected.【Result】 After 12 h anoxic stress for germinated seeds,the waterlogging tolerant(WT) genotype showed higher relative root and shoot length,fresh weight,survivor rate and relative vigor index,but lower relative electrical conductance.After 48 h anoxic stress for three leaves stage seedlings,the WT genotype showed significant different physiological reactions similar to the susceptive genotype with the rapid increase of soluble sugar and proline contents,lower relative electrical conductivity and MDA content.The different reaction also occurred in activities of activated oxygen scavenger enzyme,and thePOD and SOD activity of the WT genotype increased rapidly.CAT decreased after anoxic stress,while susceptive genotypes with similar level in SOD increased CAT but decreased POD.【Conclusion】The results suggested that WT genotype of rapeseed could increase organic osmoregulation content and activities of active oxygen scavenger enzyme increased the anoxic tolerance to waterlogging.