Analysis on yield-enhancing factors on spring maize in ton-grain field cultivation under precipitation growth | 雨养条件下春玉米“吨粮田”栽培的增产因素分析

Chinese. 对雨养条件下影响春玉米“吨粮田”产量的因素进行分析，明确“吨粮田”的增产因素。选用先玉335，采用增加种植密度、二次追肥和化学调控3项“吨粮田”栽培技术，在吉林省东部湿润冷凉区，连续3年进行“吨粮田”和常规田栽培玉米大田试验，通过栽培技术的改进研究“吨粮田”的光合生产能力，探讨“吨粮田”的增产因素。在雨养条件下，当种植密度为9万株/hm2时，“吨粮田”春玉米的平均产量由12 535.5 kg/hm2提高到16 876.5 kg/hm2，单位面积产量增加了33.37%。分析其增产因素，认为通过增加密度提高了叶面积指数（LAI）、单位面积的光合能力及干物质积累量，使最大LAI达到6.4，较对照增加了3.68%；在吐丝期通过第二次追肥提高了生育后期叶绿素含量，延长了叶片光合能力的持续期；利用化控技术克服了因高密度和二次追肥所引起的倒伏问题，保证了源的高效供给，“吨粮田”玉米的群体粒叶比较常规田高6.84%。“吨粮田”栽培可以提高群体的光合生产能力，增加群体干物质积累量和库容量。

English. The photosynthetic produce ability was studied in order to clear the yield-enhancing factors on spring maize in ton-grain field cultivation under precipitation growth. A field experiment was carried out at moist and cold areas in east of Jilin province from 2007 to 2009, and the photosynthetic produce ability of spring maize in ton-grain field cultivation was studied through the improvement of cultivation technology. The yield of ton-grain field increased by 33.37% than control field from 12 535.5 kg/hm2 to 16 876.5 kg/hm2 when the planting density was 90 000 plant/hm2. The reasons of yield-enhancing were: ① The maximum leaf area index (LAI), photosynthetic ability and plant biomass per unit land area improved greatly under high planting density, LAI was 6.4, increased by 3.68% than that of control field. ② The chlorophyll content in the late growth stage was increased, the senescence was put off and the photosynthetic duration of leaves were delayed by the second topdressing in silking stage. ③ The source’s supply was assured by adopting chemical control techniques to prevent lodging because of high planting density and topdressing twice. The results indicated that the photosynthetic produce ability and dry matter accumulation of populations were enhanced on account of ton-grain cultivation patterns, which showed that ton-grain cultivation patterns could enlarge the sink volume.