【作者】 马巧荣；

【导师】 王林权；

【作者基本信息】 西北农林科技大学 ， 植物营养学， 2010， 硕士

【摘要】 垄沟覆膜栽培具有明显的集水、保墒和增产效应。但个-群体关系仍是制约垄沟栽培冬小麦产量提高的重要因素。本试验以冬小麦品种小偃22为供试材料,采用二元二次正交旋转组合设计,通过田间小区试验研究了垄上覆膜垄沟栽培下播种量和施氮量对小麦个-群体关系的调控及其对产量的影响。试验于2008年10月-2009年6月在陕西杨凌西北农林科技大学农作一站进行,该站位于黄土高原南部,属半湿润易旱区,供试土壤为旱耕人为土垫土(红油土)。得到以下主要结论:1在供试条件下,适当提高播种量可以增加冬小麦基本苗数、冬前分蘖数、总分蘖数及群体大小。高密度低肥有利于冬前分蘖,反之则有利于春季分蘖。适当增加施肥量可以提高单位面积穗数和分蘖成穗率。低密度处理有利于小麦单株籽粒产量形成,适量种植密度下的个体优势可以弥补群体不足的缺陷。播种量与施氮量对冬小麦群体籽粒产量有明显的调节作用,氮肥对冬小麦群体产量的影响大于种植密度。常规栽培的小麦群体大小及成穗数均高于垄沟栽培;但单株产量低于垄沟栽培。只有协调好个体与群体籽粒产量的关系,才能更好的发挥垄沟覆膜栽培的增产效应。在本试验条件下,适宜的播种量为98~127kg/hm~2,施氮量为202~227kg N/hm~2;最高产量施肥量为223kg N/hm~2,播种密度为102kg/hm~2,最高产量为3851.68 kg/hm~2。2随小麦籽粒灌浆的进行,旗叶净光合速率、SPAD值和群体LAI均呈现明显的下降趋势,胞间CO2浓度、气孔导度以及蒸腾速率均升高。垄沟栽培小麦灌浆中期的叶绿素SPAD值和叶面积系数高于常规栽培处理。常规栽培下最大叶面积系数值出现在灌浆初期,垄沟覆膜栽培出现在灌浆中期(5月7日)。合理的播种量与施氮量通过调节分蘖和成穗而影响冬小麦个、群体生长。播种量为85.95 kg/hm~2 (D2),施氮量为137.57 kg/hm~2(F4)处理时,小麦旗叶光合作用、叶绿素含量及群体叶面积系数均处于较高水平。3供试条件下,低密度(78.10~105.95kg/hm~2)有利于各生育期小麦单株的干物质积累;低氮处理(158.67~185.80 kg N/hm~2)对开花期小麦个体的生长有促进作用。高氮肥(200.74~210.56 kgN/hm~2)用量可增加群体开花及成熟期的地上部干物质积累量。4施氮可促进小麦开花成熟期氮素积累及转运。垄沟、覆膜栽培的小麦个体氮素积累及转运量均高于平作栽培,而群体略低。较高播种量(109.42~120.71 kg/hm~2)有利于小麦个、群体开花期的氮素的积累,对成熟期积累不利;施氮量大于180kgN/hm~2,可促进小麦个、群体在开花期及成熟期地上部氮素积累。5个-群关系对冬小麦磷素积累和转运具有明显调控作用,成穗数是提高小麦个、群体磷素吸收、积累的关键。施用氮肥和垄沟、覆膜栽培均可提高小麦开花及成熟期群体的磷素积累及转运,有利于小麦群体效应的发挥和产量提高。在本试验中,D2F4处理的小麦个体与群体关系最为协调,最有利于磷素吸收、积累及转运。更多还原

【Abstract】 The furrow and ridge film mulching planting system (FRFM) have been regarded as effective approaches to conserve soil water and increase crop yield in dryland area. But the relationship of winter wheat individual-population restrict the yield improvement. The experiment was conducted in field by the binary quadric orthogonal rotational combination design, to research the effects of planting density and N rate on relationships of winter wheat individual and its plant population, and the effect of relationship on grain yield under ridge film mulch planting system. The tested cultivar is Xiaoyan22. The field trials were conducted from Oct. 2008 to Jun. 2009 at the Agricultural Experimental Station of Northwest A&F University, Yangling, Shaanxi province. It is a sub-humid area susceptible to drought, and located in the southern loess plateau, the soil is classified as Eum-Orthic Anthrosol. The main results obtained from the experiments are as follows:1. In this study, the basic seedling, tiller number before winter, total tiller number and the population size all increased with increasing planting density in FRFM. High-density and low N rate co-operation were benefit to tiller before winter, and low-density and high N rate coupling was benefit to spring tillers. It was increased of the number of head per unit area and the rate of heading by appropriate N rate. The yield increase of individual plant could compensate the yield lose owing to heads deficits per unit of lower density in some under the ridge planting system. Both planting density and N fertilizer had pronounced effects on the grain yield under the experiment, and the effect of N fertilizer was more significant than that of planting density. The optimum yield would be obtained with the application of nitrogen 202~227kg N/ha and density 98~127kg/ha, while the highest yield of 3851.68 kg/ha with coupling of planting density (101.75kg/ha) and N rate (222.71kgN/ha). Compared with conventional cultivation, it could increase the yield per unit area of FRFM with optimum population owing to higher yield of individual plant. In order to increase the yield of winter wheat, it was very important to coordinate the relationship of individual winter wheat and its population with the coupling of planting density and N rate.2. Results showed that the photosynthetic rate, SPAD value and LAI of wheat were obviously declined and the intercellular CO2 concentration, transpiration rate and stomatal conductance were increased during the grain filling. SPAD value and leaf area index (LAI) in FRFM were significantly higher than those of conventional cultivation in middle of grain filling. Maximum LAI of conventional cultivation was in the early filling stage, while FRFM appeared in the middle filling stage. The reasonable planting density and N rate adjusted the tiller and head number to affect the growth of winter wheat. Under D2F4 (seeding rate: 85.95kg/ hm~2, N rate: 135.57kg N/hm~2) treatment, the wheat flag leaf photosynthesis, SPAD value and LAI were all at a high level, and it’s yield was 4009kg/hm~2, was higher than that of other treatments.3. Under the conditions of the tests, low density (78.10 ~ 105.95kg/hm~2) was benefit to the dry matter accumulation of winter wheat individual; low N rate (158.67~185.80 kg N/hm~2) could promote the growth of wheat individual at anthesis. High N rate(200.74~210.56 kgN/hm~2) could increase of the shoot dry matter accumulation during anthesis and maturity stage.4. N fertilization increased N accumulation and mobilization amount at anthesis and maturity stage. There were more N accumulation and mobilization in wheat individual of FRFM than that of conventional cultivation, but the N accumulation and mobilization in wheat population were lower than that of conventional cultivation. High density (109.42 ~ 120.71 kg/hm~2) was benefit to the N accumulation of winter wheat individual and populatiin at anthesis, but its harm for N accumulation at maturity stage. N rate was higher than D3(180kgN/hm~2)treatment could promote the N accumulation of wheat individual and populatiin at anthesis and maturity stage.5. The relationship of winter wheat individual plant - population could regulate and control the relationship of P accumulation and mobilization. To improve the number of head per unit area was important to P accumulation and mobilization of winter wheat individual plant– population. N fertilization and FRFM could promote the P accumulation and mobilization . The D2F4 treatment was benfit to P accumulation and mobilization in all treatments.更多还原