【摘要】 全膜双垄沟播技术使玉米成为了陇中旱农区主要作物之一,但该技术下玉米的高产出导致土壤养分耗竭,影响玉米生产的可持续性。本研究依托2012年布设在陇中旱农区的田间定位试验,研究4个施氮水平(N0:不施肥;N1:100kg·hm^-2、N2:200kg·hm^-2、N3:300kg·hm^-2)和2个施氮时期（T1:1/3基肥+1/3拔节期+1/3开花期、T2:1/3基肥+2/3拔节期）对玉米光合特性、叶绿素含量、叶面积指数、干物质积累和分配量及产量的影响。结果表明:1)随着施氮量的增加玉米光合性能也在增强,而N3和T2N2间差异不显著,T2时期提高玉米光合特性;2)全生育期内,N3处理下叶绿素含量较N2、N1、N0分别平均增加50.9%、17.0%、2.7%;叶面积指数也随施氮量的增加而增加,但N2和N3间无显著差异;T2下的叶绿素含量和叶面积指数在生育后期显著高于T1;3)干物质积累量和籽粒分配量表现为:N3>N2>N1>N0,T2下的干物质积累和籽粒分配量高于T1;4)籽粒产量和生物产量均随施氮量的增加而增加,N2和N3下的籽粒产量和生物产量显著高于N0,其中N3较N0增加79.2%和68.4%,N2较N0增加65.9%和54.1%,T2下的籽粒产量和生物产量分别较T1显著增加9.9%和13.5%,而T2N2与N3间无显著差异,因此,在陇中旱农区应用全膜双垄沟播技术种植玉米,施纯氮200kg·hm^-2左右,按照1/3基肥+2/3拔节期配施,可以增强光合作用,从而提高玉米籽粒产量和饲料产量,促进玉米生产可持续发展。更多还原

【Abstract】 Maize has become one of the major cultivated crops in arid farming areas of central Gansu,China because of the adoption of complete film surface mulching and adoption of double ridge-furrow planting.However,the high output of maize using this technology results in exhaustion of soil nutrients negatively influencing the sustainability of maize production.The objective of this study was to determine the effects of different nitrogen application rates on the photosynthetic characteristics,chlorophyll content(SPAD),leaf area index,dry matter accumulation and distribution and yield of maize.The study relied on a field experiment that was conducted in 2012 at Dingxi,Longzhong region.The treatments included four nitrogen rates(N0:0kg·ha-1,N1:100kg·ha-1,N2:200kg·ha-1,N3:300kg·ha-1)and two nitrogen application times(T1:1/3at sowing+1/3at jointing+1/3at flowering,T2:1/3at sowing+2/3at jointing).The photosynthetic characteristics improved with increased nitrogen application rate,but there was no difference between T2N2 and N3;T2enhanced the photosynthetic characteristics.N3 increased SPAD by 50.9%,17.0%,and 2.7%respectively comparing N0,N1,and N2 at all stages.Leaf area index also improved with increased nitrogen application rate,but N2 and N3 were not different.SPAD and leaf area index under T2 were higher than T1.Dry matter during all growth stages was highest at N3 and lowest at N0(N3>N2>N1>N0)and T2 was higher than T1.Grain yield and biomass were significantly higher with increased nitrogen rates;for example,grain yield and biomass were79.2%and 68.4%higher for N3 than N0respectively,and 65.9%and 51.4%higher for N2 than N0respectively.T2 improved grain yield and biomass by 9.9%and 13.5%respectively,compared with T1.However,T2N2 and N3 were not different.The application of double furrow sowing technology,mulching with nitrogen applied at200kg·ha-1 rate,1/3applied at sowing+2/3at jointing is suggested as a means of more sustainable maize production systems in arid areas of central Gansu,China.更多还原