栽培模式对杂交粳稻常优5号根系形态生理性状和地上部生长的影响

Effects of Cultivation Patterns on Root Morph-physiological Traits and Aboveground Development of Japonica Hybrid Rice Cultivar Changyou 5

以杂交粳稻常优5号为材料,设置未施氮肥处理(0N)、当地高产栽培(对照)、超高产栽培和氮肥高效利用栽培等4种栽培模式,观察其对水稻不同生育期根系形态生理和地上部生长的影响。结果表明,不同栽培模式下水稻产量差异极显著。超高产栽培与氮肥高效利用栽培两年的平均产量分别为12.29 t hm–2和9.62 t hm–2,平均分别较对照增产41.4%和10.7%。上述两种栽培模式的氮肥农学利用率(每kg施氮量增加的产量)分别较对照增加80.7%和76.8%,灌溉水利用效率分别较对照提高62.1%和32.3%。与对照相比,超高产栽培与氮肥高效利用栽培均增加了水稻地上部干物重、叶面积指数、根干重、根长,提高了粒叶比,改善了库源关系,并提高了根冠比与根系伤流量。同时也提高了灌浆期剑叶净光合速率、根系氧化力、根系总吸收表面积与根系活跃吸收表面积,生育中后期根系、叶片以及根系伤流液中的玉米素(Z)与玉米素核苷(ZR)含量、灌浆期籽粒中蔗糖合酶(SuSase)以及腺苷二磷酸葡萄糖焦磷酸化酶(AGPase)活性。这说明,通过栽培技术的集成与优化可以提高水稻灌浆期根系和地上部的生理活性,促进水稻高产与水分养分高效利用。

The objective of this study was to investigate if a cultivation technique could coordinately increase both grain yield and nutrient use efficiency of rice through an improvement in morphological and physiological traits of roots. A field experiment was conducted using japonica hybrid rice cultivar Changyou 5 with four cultivation patterns including no nitrogen application （ON）, local high yielding cultivation （control）, super high yielding cultivation （SHY） and high nutrient use efficiency cultivation （HUEN）. The results showed that, the grain yield was 12.29 t ha-1 under SHY and 9.62 t ha-1 under HUEN, which was 41.4% and 10.7% higher than that under the control, on the average, respectively. When compared with the control, SHY and HUEN increased nitrogen （N） agronomic efficiency （the increase in grain yield divides by the amount of N application） by 80.7% and 76.8%, and irrigation water use efficiency by 62.1% and 32.3%, respectively. The SHY and HUEN also significantly increased biomass from heading to maturity, leaf area index, root dry weight and root length, grain-leaf ratio, root-shoot ratio, the amount of root bleeding, photosynthetic rate of the flag leaf, root oxidation activity, total absorbing surface area and active absorbing surface area, contents of cytokinins （zeatin ＋ zeatin riboside） in roots, leaves and root bleedings, and activities of sucrose synthase and adenosine diphosphate-glucose pyrophosphorylase in grains during grain filling. The results indicate that higher grain yield and high nutrient and water use efficiencies can be coordinately achieved through using integrating and optimizing cultivation techniques in rice production.