The responses of different planting densities (45 000 (D1 )、60 000 (D2 )、75 000 (D3 )、90 000 (D4 ) plants·hm-2 and 105 000 (D5 ) plants· hm-2 ) on dry matter accumulation and transportation of spring maize varieties were studied in 2012 and 2013 through field experiments using Zhengdan958 and Weike702 ,the main materials in the West Liaohe plain .The results showed that yields of two varieties ,and accumulation and transportation of matter followed the same patterns with the changes of planting density .The yields of two varieties were decreased first and then became increased with the planting density enhanced ,reaching the highest under the D4 density .Zhengdan958 had the highest yield of 13 .945 t·hm-2 (2012) and 13 .981 t·hm-2 (2013) ,and Weike702 had the highest yield of 16 .088 t·hm-2 (2012 ) and 14 .606 t·hm-2 (2013 ) .With the increase of planting density ,dry matter accumulation levels of two vari-eties became increased before silking ,and were subsequently decreased .The overall accumulation rates were increased before silking and went decreased afterwards .The contribution rate to grain became elevated first and then dropped with the planting density increased before silking ,while after silking ,the rate kept increased .With the increase of planting density ,leaf ,stem and sheath translocation amounts ,as well as the translocation rates of stem and sheath ,became in-creased ,whereas leaf translocation rate was decreased .The contribution rates of leaves ,stems and sheath translocation to grain reached the highest under the D4 density .With the planting density increased ,distribution rates of leaves and spikes were decreased ,and those of stem and sheath were overall increased .The grain distribution ratios became elevated first and then dropped at immature stage .With the planting density increased ,grain number and 1000-grain weight were both decreased .%以西辽河平原主推的玉米品种郑单958、伟科702为试材，设4．5万株· hm－2（D1）、6．0万株· hm－2（D2）、7．5万株· hm－2（D3）、9．0万株· hm－2（D4）和10．5万株· hm－2（D5）5个种植密度，通过2012、2013年两年的田间试验，研究了不同品种春玉米干物质积累与转运对种植密度的响应。结果表明，两品种产量、物质积累与转运随种植密度的变化规律一致。产量随种植密度的增加先升后降，在D4密度下达到最高，郑单958为13．945 t·hm－2（2012年）和13．981 t·hm－2（2013年），伟科702为16．088 t·hm－2（2012年）和14．606 t·hm－2（2013年）。随种植密度增加，吐丝前干物质积累量增加，吐丝后先升后降；积累率总体表现为吐丝前升高，吐丝后降低；对籽粒贡献率随种植密度增加先升后降，吐丝后随密度增加而增加。随种植密度的增加，叶和茎鞘的转运量增加。茎鞘转运率增加而叶转运率降低；叶、茎鞘转运对籽粒贡献率在D4密度下最大。随种植密度增加，完熟期叶和穗部营养体分配比例降低，茎鞘的分配比例总体增加，籽粒分配比例先增后降。穗粒数和千粒重均随种植密度的增加而降低。
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