水稻氮素吸收、利用与硅素营养的关系

 研究了30个水稻品种氮素吸收、利用与硅素积累的关系及高效硅肥对2个水稻品种氮素吸收与利用的影响。结果表明,水稻品种氮素积累量与硅素积累量呈极显著正相关,但氮素含量与硅素含量的相关性不显著。水稻品种的氮素干物质生产效率(NDMPE)与其体内N、P、K、Si积累的平衡有关,NDMPE与养分平衡指数呈显著正相关,与养分偏离系数呈显著负相关,但氮素吸收量与养分平衡指数和养分偏离系数的相关不显著。硅肥提高了叶片GPT转氨酶和籽粒淀粉分支酶(Q酶)活性,从而促进了水稻对氮素的吸收,但其NDMPE却随氮素积累量的增加而降

Relationship of Nitrogen Uptake and Utilization to Silicon Nutrition in Rice

In early and late seasons of 2001, 30 varieties were planted in the field experiments for determination ofnitrogen and silicon accumulation in plants. Results showed that there were highly significant correlation between nitrogenaccumulation and silicon accumulation with r of 0.7496**, 0.6046**, 0.7546** at tilling, heading and ripening stage at earlyseason respectively, and 0.7446**, 0.7758**, 0.8026** at tilling, heading and ripening stage at late season, respectively. Yetplant nitrogen content was not significantly related to silicon content. Plant nitrogen utilization was associated with thebalance of nitrogen, phosphorus, potassium and silicon accumulation, which were expressed by nutrient balance index(NBI) and nutrient deviation index (NDI). Nitrogen dry matter production efficiencies in rice varieties were positivelycorrelated with NBI and negatively correlated with NDI, but nitrogen accumulation in varieties was not related to NBI andNDI. In early season of 2002, a field experiment was carried out to study the influence of efficient silicon fertilizer on nitrogenuptake and utilization in two varieties selected from previous experiments in 2001. Results showed that efficient siliconfertilizer increased activities of GPT enzyme in leaves and Q enzyme in grains with enhanced nitrogen uptake, but decreasednitrogen dry matter production efficiency. Silicon rate had an obvious impact on decrease of Q enzyme activity during grainfilling, high silicon rate resulted in rapid decrease of Q enzyme activity.