【作者】 刘广才；

【导师】 黄高宝； 张福锁； 李隆；

【作者基本信息】 甘肃农业大学 ， 作物栽培学与耕作学， 2005， 博士

【摘要】 本研究以西北一熟制灌区当前生产中广泛种植、且间套优势明显的春大麦/春玉米、春小麦/春玉米等禾本科/禾本科间套作方式为研究对象,通过大量的田间小区试验、根系分隔微区试验和根系分布测定,从间套作作物地上部生长和养分吸收积累动态、地下部根系时空分布动态等角度,研究了春大麦/春玉米和春小麦/春玉米间套作、春小麦/不同品种春玉米间套作中不同种类作物和不同品种作物营养竞争能力和恢复能力的差异,特别是氮、磷、钾营养竞争和恢复能力的差异。系统地阐明了不同间套作系统种间营养竞争、恢复作用的差异性及其机理,获得的主要结果为:1)间套优势不仅可以通过作物组合来获得,也可通过施肥和覆盖地膜等措施调控。在大麦/玉米和小麦/玉米间套作生态系统中,以籽粒产量计算的土地当量比(LER)分别为0.99-1.32和1.08-1.41;以生物学产量计算的土地当量比分别为0.98-1.31和1.06-1.42。大麦/玉米间套作产量优势只有在施氮并且玉米覆膜时较明显;而小麦/玉米间套作在施氮、玉米不覆膜条件下就有明显的间套作产量优势,在施氮、玉米覆膜条件下间套作产量优势更加显著。大麦/玉米和小麦/玉米两种间套作在相同条件下的间套作养分吸收优势与产量优势的趋势类似。2)玉米品种对小麦/玉米间套作产量优势具有重要影响。在小麦与不同品种玉米间套作中,以籽粒产量和生物学产量计算的LER分别为1.09-1.35和1.10-1.35,LER随玉米品种的变化顺序为沈单16号>豫玉22号>中单2号>酒单2号和新玉4号,这些品种特性也相应为中晚熟、晚熟、中熟、早熟,表明间套优势也与玉米的生物学特性密切相关。小麦/不同品种玉米间套作在相同条件下的间套作养分吸收优势与产量优势的趋势类似。3)间套大麦的边行产量优势明显的高于间套小麦,间套大麦的边行养分吸收量优势也明显大于间套小麦。间套大麦边行籽粒产量和生物学产量分别比内行增加95.5%-116.9%和114.5%-128.8% ;相应地,间套小麦分别为57.6%-81.6%和66.0%-106.5%,间套小麦边行产量优势随玉米品种特性由晚熟到早熟呈降低趋势。间套大麦边行氮、磷和钾养分的吸收量分别比相应内行高出124.1%-149.3%、133.5%-149.1%和147.2%-157.9%;而间套小麦相应分别为74.5%-115.5%、76.7%-115.1%和80.4%-137.4%,与中晚熟玉米种间套的小麦边行氮、磷和钾养分吸收优势明显地高于与早熟玉米种间套的小麦。更多还原

【Abstract】 In this study, two intercropping systems with widely-use and apparent yield advantage (i.e. spring wheat/ spring maize and spring barley/ spring maize intercropping) were used to investigate the growth of aboveground, nutrient uptake dynamics and temporal and spatial root distribution with the emphasis on competition for N,P,K and compensatory (recovery) ability, and the main results were following as:1) Intercropping advantage could be improved by cropping selection and fertilization and mulching. Land Equivalent Ratio (LER) of spring barley/ spring maize intercropping and spring wheat/ spring maize intercropping were 0.99-1.32 and 1.08-1.41 based on grain yield, and 0.98-1.31 and 1.06-1.42 based on biomass, respectively. Yield advantage of spring barley/ spring maize intercropping was apparent under fertilization and mulching for maize. Yield advantage of spring wheat/ spring maize intercropping, however, was apparent with only fertilization, and would be more advantage when maize was mulching at same time. Nutrition advantage was similar with yield advantage under the same condition in spring barley/ spring maize intercropping and spring wheat/ spring maize intercropping.2) Cultivars of maize had substantial effect on yield advantage of spring wheat/ spring maize intercropping. In different maize cultivar experiment, LER was 1.09-1.35 and 1.10-1.35 based on grain yield and dry matter yield, respectively. LER of intercropping with different maize cultivar changed in the order: Shendan No. 6>Yuyu No.22 > Zhongdan No.2 > Jiudan No.2 > Xinyu No.4, and the growth duration is in the same order with long duration for high LER, which indicates there was good relationship between intercropping advantage and biological characteristics of maize. Nutrient uptake characteristics were similar with yield advantage.3) Yield advantage of border rows of intercropped barley was much greater than that of intercropped wheat. Grain yield and dry matter in border rows of intercropped barley were 95.5%-116.9% and 114.5%-128.8% higher than its corresponding inner rows, while 57.6-81.6% and 66.0-106.5%, respectively, for intercropped wheat. Yield advantage of border rows of intercropped wheat increased with the length of maize growth duration. Advantage in border rows of nutrient uptake for intercropped barley was also greater than intercropped wheat. N,P,K acquisition in border rows of intercropped barley was 124.1%-149.3%, 133.5%-149.1% and 147.2%-157.9% higher than corresponding inner rows, while 74.5%-115.5%, 76.7%-115.1% and 80.4%-137.4%, respectively, for intercropped wheat. N,P,K nutrient advantage in border rows of wheat intercropped with maize of late growth duration was apparently higher than that of wheat intercropped with maize of early growth duration.4) When fertilized and mulching for maize, yield advantage of spring maize/ spring barley intercropping was mainly attributed to aboveground, 80% from aboveground and 20% from underground. With fertilization and non-mulching for maize, the relative contribution of yield advantage of spring wheat/ spring maize intercropping from aboveground and underground accounted for 75% and 25%, whereas 2/3 and1/3 with both fertilization and mulching for intercropped maize.5) Barley and wheat were more competitive than maize; however, barley had much more competition power than wheat. There were two main mechanisms. First, barley was more competitive than更多还原