【摘要】 在盆栽条件下 ,设计基肥、分蘖肥、促花肥、保花肥等 7个不同时期氮肥处理 ,研究其对扬稻 6号根系生长及产量的影响。结果表明 :①施用基肥、分蘖肥均能显著提高拔节期、倒 2叶期每株不定根数、不定根总长度和根干重 ;②在施氮量较少的情况下 ,无论是作为基肥 ,还是作为分蘖肥、促花肥施用 ,均能显著提高抽穗期的每株不定根数、不定根总长度和根干重 ,且施氮时期越早 ,促进作用越大 ;③在施用分蘖肥的基础上 ,施用促花肥能显著提高每株根干重 ,施用保花肥可促进不定根的伸长 ,增加每株不定根总长度 ;④产量随着每株根干重、每株不定根数、单位长度不定根重的提高而增加 ,相关系数分别为 0 .8386 、0 .715 9 、0 .5 5 47 。更多还原

【Abstract】 Pot experiment with 7 treatments was conducted during 1997~1998 to investigate effects of nitrogen fertilizer applied at different growth stages on root growth and grain yield of Yangdao 6 ( Oryza sativa L.). Nitrogen was applied as basal or as top dressing for tillering, spikelet promoting and spikelet sustaining. Results were as follows: ① Basal nitrogen and top dressing at tillering stage significantly increased the number of adventitious roots, the total length of the roots and root dry weight per plant in internode elongation stage and in leaf age remainde. ② Low rate of N application could significantly increase the number of adventitious roots, the total length of the roots and root dry weight per plant, regardless of applying as basal, tillering or spikelet promoting fertilizer. Earlier application was more effective. ③ Combination of top dressing N as tillering and spikelet promoting N significantly increased root dry weight. Combination of top dressing N as tillering and spikelet sustaining N stimulated the elongation of adventitious roots, and increased the total length of roots per plant. ④ Grain yield per plant had close correlation with root dry weight per plant, the number of adventitious roots per plant and dry weight per unit length of root, i.e., correlation coefficients ( r , df=12) were 0.838 6 ** , 0.715 9 ** and 0 554 7 *, respectively.更多还原