春性和半冬性小麦植株氮素积累与运转特征差异

以江苏省6个半冬性和9个春性小麦品种为材料,研究两类型小麦品种在大田条件下的氮素积累、运转和分配差异.结果表明: 施氮量相同条件下,半冬性小麦群体植株平均氮素积累量在越冬始期-拔节期低于春性小麦群体,孕穗期-成熟期高于春性小麦群体;氮素阶段累积量在越冬始期-拔节期两类型群体间差异不显著,开花-成熟期半冬性群体显著高于春性群体.半冬性小麦平均总氮素转运量、花后积累量显著高于春性小麦;两种类型小麦总氮素转运率、积累氮贡献率、总转运氮贡献率差异均不显著.半冬性小麦营养器官中叶片氮素转运量、转运率、转运氮贡献率均低于春性小麦,茎鞘氮素转运量、转运率、转运氮贡献率则高于春性小麦,茎鞘氮素转运量差异达显著水平;同一类型内不同品种间植株氮素积累量、总氮素运转量、花后氮素积累量、总氮素转运率、总转运氮贡献率等均存在差异.生产中应根据不同品种吸收、利用、运转氮素能力的差异,合理运筹生育期氮肥用量和施用比例,提高氮肥利用率.

Difference in nitrogen accumulation and translocation between semi-winterness and springness wheat.

Nitrogen accumulation, translocation and allocation were investigated in a field experiment to find out the difference between six semi-winterness wheat cultivars and nine springness wheat cultivars that are mainly grown in Jiangsu. Results indicated that the average nitrogen accumulation amount (NAA) in the semi-winterness wheat cultivars was lower from the beginning of wintering to jointing stage, but higher from booting to maturity stage, compared with the springness wheat cultivars tested under the same rate of nitrogen fertilization. The amount of nitrogen accumulated between the beginning of wintering and jointing stage showed no significant difference between the two types of wheat cultivars, but that accumulated between anthesis and maturity in the semi-winterness wheat cultivars was higher than that in the springness wheat cultivars. The total N translocation amount (TNTA) and N accumulation amount to grains after anthesis (NAAA) were significantly higher in the semi-winterness wheat cultivars than those in the springness wheat cultivars, but the total N translocation efficiency (NTE), the contribution proportion of accumulated N (ANCP), and the contribution proportion of translocated N (TNCP) did not show significant difference between the two types of wheat cultivars. In leaves, the semi-winterness wheat cultivars showed lower TNTA, NTE and TNCP than the springness wheat cultivars, but in stem and sheath these N indexes were higher in the semi-winterness wheat cultivars, with a significant level for TNTA. These were significant differences in NAA, NAAA, TNTA and TNCP among cultivars with the same spring type or semi-winter type. According to the differences in nitrogen absorption, utilization and translocation among different wheat cultivars, nitrogen utilization efficiency could be improved by using approp-riate amount and reasonable proportion of nitrogen fertilizers at different developmental stages of wheat.