长期免耕覆盖对旱地冬小麦旗叶光合特性及干物质积累与转运的影响

doi:10.11674/zwyf.2015.0203

CORC > 中国农业科学院 > 农业环境与可持续发展研究所 > 旱作节水研究室

	长期免耕覆盖对旱地冬小麦旗叶光合特性及干物质积累与转运的影响
	王健波; 严昌荣; 刘恩科; 陈保青; 张恒恒
刊名	植物营养与肥料学报
	2015
卷号	21 期号:2 页码:296-305
关键词	旱地小麦免耕覆盖光合有效辐射土壤水分干物质积累与转运光合特性
ISSN号	1008-505X
DOI	10.11674/zwyf.2015.0203
其他题名	Effects of long-term no-tillage with straw mulch on photosynthetic characteristics of flag leaues and dry matter accumulation and translocation of winter wheat in dryland
英文摘要	[目的]小麦开花后光合特性对干物质积累和转运具有重要作用,而土壤水分是影响作物光合作用最重要的环境因子。研究长期定位试验条件下免耕覆盖的蓄水保墒作用和小麦冠层光合有效辐射传输特征,及其对小麦光合特性和干物质转运规律的影响,以期为旱区作物生产及农田高效用水提供理论依据。[方法]本文以山西临汾20年免耕覆盖和常规耕作两种耕作方式的长期定位试验为平台,于2013年休闲期和小麦生育期对土壤水分,小麦生育后期光合有效辐射、旗叶光合参数、干物质积累和产量构成因素进行了测定。[结果]在休闲期和小麦生育期,与常规耕作方式相比,免耕覆盖耕作0-160 cm土层土壤储水量显著增加,平均提高了12%,其中在土壤水分含量的最低时期(灌浆前期)比常规耕作提高21%(P<0.01)。在抽穗和灌浆前期免耕覆盖处理的小麦截获的光合有效辐射比常规耕作高163 μmol/(m~2·s),其中在灌浆前期二者差异最大,达19.3%(P<0.05),并且免耕覆盖下小麦中上层和中下层都有充分利用光能的机会。在灌浆前期免耕覆盖比常规耕作处理的小麦旗叶气孔导度平均增加39%,二氧化碳利用能力平均增加11%,瞬时水分利用效率提高了22%;小麦抽穗后到成熟期免耕覆盖处理的小麦旗叶净光合速率平均比常规耕作高39%,收获期籽粒重和植株总重分别比常规耕作高57%和46%(P<0.01),并且开花后干物质积累量对籽粒的贡献率达到了64%。从产量构成因素来看,免耕覆盖的小麦穗数和千粒重分别比常规耕作高31%和10%,实收产量比常规耕作高41%(P<0.01)。免耕覆盖耕作方式下的土壤蓄水保墒能力缓解了因水分胁迫作用而出现的光合午休现象,保证了小麦光合速率处于较高水平;同时免耕覆盖增强了小麦开花后干物质的积累能力,并且籽粒干物质的主要来源是开花后干物质的积累,而常规耕作则是以开花前贮藏的同化物量为主要来源。[结论]在晋南旱区,采用长期免耕覆盖的耕作方式可提高土壤水分的保蓄能力和光能截获能力,增强冬小麦的净光合效率、瞬时水分利用效率及干物质积累与转运,协调产量构成因素之间的关系,提高小麦产量。; [Objectives] Photosynthetic characteristics of winter wheat after flowering play an important role in dry matter accumulation and transportation, and soil moisture is the most important environmental factor which affects the crop photosynthesis. Application of no-tillage could improve the soil environment and increase the crop production. To study role of water reserving and soil moisture keeping under no-tillage with straw mulch practice in a long-term experiment, and transfer characteristics of canopy photosynthetically active radiation and their effects on photosynthetic characteristics and dry matter transportation of wheat, we conducted this experiment in the long-term plots. [Methods] These plots were established in a silt loam soil in the Loess Plateau of China in 1992, and consisted of no-tillage with straw mulch (NT) and conventional tillage (CT) with three replications. The soil of this semi-arid area is a Chromic Cambisol, which is low in organic matter and slightly alkaline and which is subject to frequent drying and wetting cycles. The soil moisture, and photosynthetically active radiation, flag leaf photosynthetic characteristics, dry matter accumulation and yield components of wheat were measured during the fallow period and wheat-growing period under different tillage practices. [Results] During the fallow period and wheat-growing period, a significant increase of water-storage capacity under the NT practice is found in 0-160 cm soil depth compared with CT, with an average increase of 12%. At its lowest point (at the pre-filling stage), soil moisture under the NT practice is 21% higher than that of the CT practice(P<0.01). The canopy photosynthetically active radiation intercepted under the NT practice is 163 μmol/(m~2·s) higher than that of the CT practice at the heading and filling stages, which reaches the maximum difference (19.3%) at the pre-filling stage (P<0.05), and both upper and bottom wheat canopies under the NT practice have opportunity to use light energy. Compared with the CT practice, the NT practice increases the stomatal conductance with an average of 39% at the pre-filling stage, enhances the ability of carbon dioxide utilization by 11%, and improves WUE by 22%. From the heading to mature stages, the net photosynthesis rate under the NT practice is 39% higher than that of CT, the grain weight and total plant weight at the harvest stage are 57% and 46% higher than those of CT respectively (P<0.01), and the contribution of dry matter accumulation into grain after the flowering reaches 64%. From the point of view of yield components, the NT practice had the significant effect on wheat spike number and thousand grain weights, 31% and 10% higher than the CT practice respectively. The yield under the NT practice was 41% higher than the CT practice (P<0.01). The study indicates that the ability of water reserving and soil moisture keeping under no-tillage with straw mulch practice could alleviate the decline of net photosynthesis rate in midday due to the action of water stress, and keep wheat photosynthesis at a high level. Meanwhile, the NT practice enhances the ability of dry matter accumulation after the anthesis, and the dry matter accumulation after the anthesis is the main source of dry matter accumulation into grain under the NT practice, while under the CT practice the dry matter accumulated in vegetative organs before the anthesis is the main source of dry matter accumulation into grain. [Conclusions] The results indicate that the long-term no-tillage with straw mulch practice could significantly improve soil moisture and light interception ability, enhance wheat photosynthesis characteristics, WUE and dry matter accumulation and transportation, coordinate relationship between the yield components and increase wheat production in the dryland of the south of Shanxi Province.
学科主题	农学(农艺学) ; 农作物
语种	中文
内容类型	期刊论文
源URL	[http://111.203.20.206/handle/2HMLN22E/16880]
专题	农业环境与可持续发展研究所_旱作节水研究室
作者单位	中国农业科学院农业环境与可持续发展研究所, 农业部旱作节水农业重点开放实验室, 北京, 100081
推荐引用方式 GB/T 7714	王健波,严昌荣,刘恩科,等. 长期免耕覆盖对旱地冬小麦旗叶光合特性及干物质积累与转运的影响[J]. 植物营养与肥料学报,2015,21(2):296-305.
APA	王健波,严昌荣,刘恩科,陈保青,&张恒恒.(2015).长期免耕覆盖对旱地冬小麦旗叶光合特性及干物质积累与转运的影响.植物营养与肥料学报,21(2),296-305.
MLA	王健波,et al."长期免耕覆盖对旱地冬小麦旗叶光合特性及干物质积累与转运的影响".植物营养与肥料学报 21.2(2015):296-305.