【摘要】 2003和2004年,在盆栽条件下以两系超级杂交稻两优培九为材料,设计9个氮肥处理,研究施用氮肥对抽穗期12个根系性状的影响及根系性状与氮素吸收的关系。结果表明:年度间单株不定根数的差异较小,其余11个根系性状以及成熟期氮素累积量的年度间差异均很大;氮处理对抽穗期12个根系性状以及成熟期氮素累积量均有显著或极显著影响;年度与氮处理对单株根干重、单条不定根粗、单条不定根干重、单株根系α-NA氧化量、单株根系总吸收面积和活跃吸收面积以及成熟期氮素累积量的互作效应均达到显著或极显著水平。在各施氮处理中,增施和早施氮肥能显著增加单株不定根数,施氮量较少且作1次施用时,氮肥作基肥施用的处理单株不定根总长度和根干重最大,施氮量较多且作2次施用时,以基肥+保花肥施氮组合的单株不定根总长度、根干重、根系α-NA氧化量、根系总吸收面积和活跃吸收面积最大。抽穗期单株的不定根数、不定根总长度、根干重、根系α-NA氧化量、根系总吸收面积、根系活跃吸收面积与成熟期氮素累积量均呈极显著线性正相关(r=0.591**～0.850**)。更多还原

【Abstract】 The pot experiments with 9 nitrogen treatments were conducted in 2003—2004 to study the effects of nitrogen application on 12 root traits responsible for morphology and physiological activity and the correlation between the root traits at heading stage and nitrogen absorption in two-line super hybrid rice Liangyou Peijiu.The results showed that there existed a significant difference between the years of treatments in N accumulation in plants at maturity and all of the root traits tested at heading in this study except the number of adventitious roots per plant;all root traits at heading and N accumulation at maturity were significantly influenced by nitrogen treatments;the interaction between year and nitrogen treatments on root dry weight per plant,mean of single adventitious root diameter,mean of single adventitious root dry weight,total α-NA oxidizing amount of roots per plant,total absorption area of roots per plant,active absorption area of roots per plant and N accumulation at maturity were significant.Among the nitrogen treatments,those with early and more N application could increase significantly the number of adventitious roots per plant.When the nitrogen fertilizer was applied only once and at a smaller amount,the treatment BF,i.e.,the basal application,had the largest values in the total length of adventitious roots and dry weight of roots per plant,while the treatment BF+SSF,i.e.,the basal application plus the spikelet-sustaining topdressing,had the biggest values in the total length of adventitious roots,dry weight of roots,α-NA oxidizing amount of roots,total absorption area and active absorption area of roots per plant when the nitrogen fertilizer was applied twice and at a bigger amount.The correlation analysis showed that N accumulation at maturity was closely related to such roots traits at heading as the number of adventitious roots per plant,total length of adventitious roots per plant,root dry weight per plant,total α-NA oxidizing amount of roots per plant,total root absorption area per plant and the active absorption area of roots per plant,with the correlation coefficients from 0.591** to 0.850**.更多还原