【摘要】 本文在建立品种改良在玉米增产中的科技贡献分析模型的基础上,计算了我国三大玉米区科技进步、品种改良、化肥投入和经营管理等其他措施引起产量的变化,涉及到玉米生产大省吉林等为主的九个省(区)。结果表明:1985～1994年期间,良种的推广应用和化肥投入是玉米增产的两大主导因素,经营管理等其他因子限制性作用明显。在科技进步对产量增产的平均贡献中,品种改良占35.5％,化肥投入占51.4％,经营管理等其他措施仅占13.1％。今后在广泛应用高产高抗耐密优良品种的基础上,要确保一定的物质投入水平,突出加强技术管理,才能充分发挥良种生产潜力和提高良种综合生产力。更多还原

【Abstract】 On the base of setting up the model of contributions of maize improvement toyield increment due to technology, the yield gains from maize improvement, chemical fertilizerinputs, management and other measures in 3 major corn production zones including 9 provincesin China were calculated. It is showed that expanding the improved maize(mainly hybrid maize)and chemical fertilizer inputs play an important role in corn yield increases. The average percentage contributions of maize improvement to yield increases due to technology is 35. 5% (from 22%to 49%), chemical fertilizer is 51. 4% (from 38% to 65%), and management and other measurements is 13. 1% (from 3% to 28%). From now on, the high-yield, high-efficy and density-resistant improved maize should be the dominant factors, while maintainning the proper level ofchemical fertilizer inputs, and enhancing the management and other measures.更多还原