基于Hybrid Maize 模型的3个生态地点玉米产量潜力评估

EVALUATION OF MAIZE YIELD POTENTIAL AT THREE ECOLOGICAL SITES BASED ON HYBRID MAIZE MODEL

关键词:  玉米直播晚收增密产量潜力

Key words:  maize  direct planting  delay harvest  increasing planting density  yield potential

摘要:

［目的］准确评估玉米高产措施的增产潜力，量化设计高产玉米技术模式，为合理应用玉米高产措施挖掘玉米产量潜力提供理论依据和技术参考。［方法］选取北京、泰安和榆林为研究地点，以当前大面积推广应用的玉米品种郑单958为供试品种，利用Hybrid Maize模型，对“直播”、“晚收”和“增密”3种主要玉米高产措施下的玉米产量潜力动态响应规律进行模拟分析，进而设计构建适宜不同地点的玉米高产技术模式并评价其较当前生产模式下的增产潜力。［结果］在北京和泰安，播期推迟至5月20日后有利于玉米产量潜力增加，直播较套种措施下的玉米产量潜力在北京和泰安分别提高18%和20%； 适时晚收可有效增加玉米产量潜力，在中产年份，每推迟收获1d，产量潜力在北京和泰安分别能够增加214kg/hm2和204kg/hm2； 增密措施是提高产量潜力的重要措施，不同地点均表现为在密度高于7万株/hm2后，增产效应降低。不同生态区的玉米合理密度不同，北京和泰安的合理密度在75万~8万株/hm2，榆林的合理密度在85万~9万株/hm2； 当前的管理措施下，不同地点玉米长期平均产量潜力为12~15t/hm2。通过措施优化组合能有效提高玉米产量潜力，不同地点措施优化途径不同。总体上，设计构建的高产技术模式较当前生产模式下的玉米长期平均产量潜力提高15％～41％。［结论］当前玉米生产主推技术（直播、晚收、增密）能有效提升玉米产量潜力，但其适用范围在不同地点有所不同，Hybrid Maize模型是实现玉米定量设计栽培的重要手段。

Abstract:

To accurately evaluate the yield increase potential of high yield maize practices and quantitatively design the technical model of high yield maize could provide theoretical basis and technical reference for rational application of high yield measures of maize to exploit the maize yield potential. Beijing, Tai′an and Yulin were selected as the study sites. Zhengdan 958, a maize cultivar widely used at present, was selected as the test cultivar. The dynamic responses of maize yield potential under three main high yield measures of "direct seeding", "late harvest" and "increasing planting density" were simulated and analyzed. Then, we designed the maize high yielding technology model suitable for different sites and evaluated its yield increasing potential compared with the current production model. In Beijing and Tai′an, delaying sowing date to May 20th is beneficial to maize yield potential increase, and compared with intraplanting measures, direct sowing increase maize yield potential by 18% and 20% at Beijing and Tai′an respectively. Properly late harvest can increase maize yield potential effectively. In median yield year, yield potential can be increased by 214 kg/hm2 and 204 kg/hm2 in Beijing and Tai′an respectively for each delayed harvest day. Increasing planting density is an important practice to increase yield potential. The effect of yield increase decrease for different sites when the planting density is higher than 70 000 plants/hm2. The optimal planting density of maize is different for different ecological regions. The optimal planting density in Beijing and Tai′an is 75 000 to 80 000 plants/hm2, and that in Yulin is 85 000 to 90 000 plants/hm2. Under the current management measures, the long term average yield potential of maize in different sites is 12 to 15 t/hm2. Optimizing the combination of practices can effectively improve the maize yield potential, and optimal practices in different locations are different. Overall, the long term average yield potential of maize under the designed high yield technology model is 15% to 41% higher than that under the current production model. Currently recommended practices for maize production (direct seeding, late harvest, increasing planting density) can improve maize yield potential effectively, but its application range varies from place to place. Hybrid Maize model is an important means to maize cultivation based on quantitative design.