孕穗期土壤渍水逆境对冬小麦根系衰老的影响

以耐湿性不同的3个冬小麦栽培品种为试验材料，采用土柱栽培法，研究了孕穗期土壤渍水逆境对冬小麦根系生长发育、³²P的吸收、分配及根系衰老的影响。结果表明，孕穗期土壤渍水逆境初期（0～5 d），单株根干重略有增加；渍水5 d后，根系干重、根系活力和根系SOD活性开始下降，根系质膜相对透性和膜脂过氧化水平（M

Effects of Waterlogging on Senescence of Root System at Booting Stage in Winter Wheat

The effects of waterlogging to growth and development of root system at booting stage,()~(32)P absorption and distribution,and senescence of root system were studied with soil column culture method,using 3 winter wheat cultivars with different waterlogging-resistance.Waterlogging at early booting stage(05 days after treatment) increased a little dry weight(DW) of root system per plant.Five days after treatment,the root dry weight,root system activity and SOD activity began to decrease,and the relative permeability of plasma membrane and membrane-lipid preoxidation level(MDA content) of root system rose.Ten days after treatment,the root dry weight,root system activity and SOD activity decreased sharply,while the relative permeability of plasma membrane and membrane-lipid preoxidation level(MDA content) of root system increased rapidly.Till the 20th day of treatment,the root system activity and SOD activity reached the lowest levels,and the relative permeability of plasma membrane and membrane-lipid preoxidation level(MDA content) reached the highest.With the process of waterloging stress,the root system was damaged even severely duo to anaerobic respiration,indicating the main physiological factor for wheat premature senescence.The results also showed that waterlogging affected()~(32)P absorption,transportation and distribution in wheat at booting stage,and speeded up senescence of root system consequently.