中文摘要：

【目的】研究水稻生长前期不同施肥深度对水稻根系生长及分布的影响,揭示浅层施肥对水稻苗期生长的重要作用,以期为水稻的合理施肥提供依据。【方法】本试验于华中农业大学盆栽场进行,采用盆栽土柱培养试验方式,设置不施肥和施肥深度1、5、10、15 cm共5个处理,分别于播种后10、20、30和40 d取样4次,研究不同施肥深度对水稻苗期根系生物量、根系形态指标、根系总吸收面积及活跃吸收面积、根系分布及地上部生物量的影响。【结果】播种后10 d,各处理间无显著差异；播种后20 d,施肥深度1 cm处理水稻根系生物量、形态指标参数、根系吸收面积等指标均显著优于其它处理,具体表现为施肥深度1 cm＆gt；5 cm、10 cm、15 cm＆gt；不施肥处理（CK）；地上部生物量也表现出相同趋势。播种后30 d,施肥深度1 cm处理的优势更加明显,与施肥深度5 cm相比,根系生物量、地上部生物量分别显著增加163.8%、121.5%。播种后40 d,地上部生物量表现为1 cm＆gt；5 cm＆gt；10 cm、15 cm＆gt；CK,施肥深度5 cm处理分别比10 cm、15 cm处理增加37.6%和34.6%。播种后40 d,根系分布结果显示,各处理均有60%以上根系分布于0—10 cm土层；施肥处理根系在各土层的生物量均显著高于不施肥处理,其中施肥深度1 cm处理的10—15 cm、15—20 cm根系分布比例显著高于其他处理,与施肥深度5 cm相比,增幅达26.1%和84.0%。【结论】不同施肥深度对水稻苗期根系生长及分布产生明显的影响。整个试验期间,施肥深度1 cm处理根系生物量、各形态指标参数及根系吸收面积都表现出明显优势,根系活力及下层根系比重均有所提高,有利于良好根系构型的建成。适宜的浅层施肥可以明显促进水稻生长前期根系生长发育,同时地上部生物量表现出显著的优势,这也是对根系生长及分布状况的积极响应。

英文摘要：

【Objective】 The aim of the research was to study the effects of different fertilization depths on growth and distribution of rice roots at seedling stage, and to ascertain the importance of fertilizer in shallow soils on the rice growth and thus providing information for appropriate fertilization. 【Method】 The trial was performed at the experimental base of Huazhong Agricultural University. Five treatments were designed, which were no fertilizer and fertilization depths of 1 cm, 5 cm, 10 cm, and 15 cm. According to the growth period of rice, samples were taken on 10, 20, 30 and 40 d after sowing. Several parameters were tested, including root biomasses, morphological index parameters, absorbing surface area and shoot biomasses of rice to assess the effect of different fertilization depths on rice seedling growth.【Result】 The results showed that no significant differences were observed among treatments on 10 d after sowing The root biomass, morphological index parameters and absorbing surface area of 1 cm treatment were significantly higher than those of others on 20 d after sowing. The increment effects were 1 cm5 cm, 10 cm, 15 cmCK, and the shoot biomass had same tendency. The biomasses of rice root and shoot of 1 cm treatment were increased by 163.8% and 121.5% compared to those of 5 cm treatment on 30 d after sowing. The shoot biomasses differed among the treatments, the order of which was 1 cm5 cm10 cm, 15 cm CK, and that of 1 cm treatment were 37.6% and 34.6% higher than those of 10 cm and 15 cm treatment, respectively on 40 d after sowing. Additionally, the results of root distribution indicated that 60% of rice roots concentrated in the 0-10 cm soil layer on 40 d after sowing. The root biomass of each soil layer in the fertilization treatments was higher than that of no fertilization treatment. The lower root biomasses of 1 cm treatment were significantly increased, which was 26.1% and 84.0% higher than other treatments in the 10-15 cm and 15-20 cm soil layers, respectively. 【Conclusion】 Di