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141.
142.
随着粮食增产的迫切需求和化肥工业的快速发展,我国种植业与养殖业养分物质循环断裂,推进种养结合成为实现农业绿色发展重要途径。但目前,我国从农户层面以及区域层面都存在着种植与养殖之间的纽带断裂,造成了农业资源利用的错位,也产生了资源环境双重压力。推进种养结合的堵点主要表现在养殖场责任尚未压实、有机肥施用不便利、堆肥质量标准缺失、社会化服务体系不完善等多方面。本文结合对国内和国际上推进种养结合的典型做法的分析,在强化提升国家粮食安全保障能力的大背景下,从优化种养布局规划、压实养殖主体责任、强化科技支撑、培育社会化服务组织等方面提出了当前构建全新的种养循环体系的建议。 相似文献
143.
为实现弱筋小麦优质稳产,解决当前弱筋小麦存在品质稳定性差的问题。本试验以弱筋小麦‘宁麦13’为试材,结合方差分析等方法研究增密减氮对弱筋小麦的产量、群体质量指标以及籽粒品质的影响。结果表明,在240 kg/hm2施氮水平条件下,随着密度的增加,小麦LAI、干物质积累量均呈先增加后下降的趋势,密度超过240×104/hm2会导致LAI、干物质积累量、产量下降。在240×104/hm2密度条件下,施氮量超过240 kg/hm2会导致小麦叶面积指数、SPAD值、花后干物质积累量和产量下降。适当的增密减氮有利于提高弱筋小麦的优质稳产,而过量增密减氮则会导致小麦产量下降,品质不稳定。为实现产量和品质的最优化,生产上推荐采用种植密度为240×104/hm2,施氮量为180 kg/hm2,氮肥运筹为7:1:2:0的栽培模式。 相似文献
144.
145.
通过对泰兴香荷芋施肥量研究,考查了各处理主要生育期的苗情与长势、成熟期子孙芋产量及商品芋产值效益。结果显示:基施腐熟脱水猪粪15t·hm-2,苗期追施(3.1叶)脱水猪粪15t·hm-2+13-10-18高钾复合肥675kg·hm-2的处理子孙芋产量最高为23 421.90kg·hm-2,商品芋效益为88 506.60元·hm-2;基施有机肥7 500kg·hm-2+苗期追施(3.1叶)有机肥7 500kg·hm-2+13-10-18高钾复合肥450kg·hm-2+膨大肥(8.1叶)13-10-18高钾复合肥900kg·hm-2的处理产量相对较高。 相似文献
146.
晚稻机收留高茬紫云英迟播技术的应用效果研究 总被引:2,自引:0,他引:2
通过田间试验,研究了双季稻田晚稻机械收获留高茬后紫云英迟播的应用效果。结果表明,与传统紫云英播种技术相比,晚稻机械收获留高茬紫云英迟播显著缩短了紫云英的生育期,但其盛花期能保持与传统播种技术一致,对下茬早稻作物的种植没有影响;两种播种方法对盛花期鲜草产量、植株养分含量和养分积累量均没有显著影响,说明迟播播种能达到与传统播种一样的肥田目的;迟播对紫云英的种子产量及产量构成因素均没有明显影响,与传统播种技术相比可节约劳动力成本约45元/hm2,且可避免传统播种方法对晚稻植株的伤害。在现代双季稻种植条件下,晚稻机械收获留高茬紫云英迟播技术具有较大的优势和发展前景。 相似文献
147.
以郑单958和豫单606为试验材料,采用盆栽试验方法,探索不同硼肥用量对玉米产量及生长发育的影响。结果表明,施用适量硼肥可促进玉米生长发育,显著提高叶面积指数,使植株干物质积累量增加,同时硼肥能够促进干物质向果穗运输。施用硼肥能够促进玉米穗分化,使雌雄间隔期缩短,显著提高花丝数和花丝生长速率,进而增加穗粒数。施用硼肥显著提高玉米产量,且不同用量对其影响不同,3.33 mg/kg土壤硼肥处理的效果最为显著,郑单958和豫单606分别较不施硼肥处理增产14.3%和17.4%;施用量为13.3 mg/kg时郑单958增产3.5%;豫单606产生中毒症状,产量较对照降低4.4%。 相似文献
148.
XU Xin-peng HE Ping CHUAN Li-min LIU Xiao-yan LIU Ying-xia ZHANG Jia-jia HUANG Xiao-meng QIU Shao-jun ZHAO Shi-cheng ZHOU Wei 《农业科学学报》2021,20(10):2772-2780
Quantification of currently attainable yield and fertilizer requirements can provide detailed information for assessing the food supply capacity and offer data support for agricultural decision-making. Datasets from a total of 5 408 field experiments were collected from 2000 to 2015 across the major wheat production regions in China to analyze the spatial distribution of wheat yield, the soil nutrient supply capacity(represented by relative yield, defined as the ratio of the yield under the omission of one of nitrogen(N), phosphorus(P) and potassium(K) to the yield under the full NPK fertilizer application), and N, P and K fertilizer requirements by combining the kriging interpolation method with the Nutrient Expert Decision Support System for Wheat. The results indicated that the average attainable yield was 6.4 t ha~(-1), with a coefficient of variation(CV) of 24.9% across all sites. The yields in North-central China(NCC) and the northern part of the Middle and Lower reaches of the Yangtze River(MLYR) were generally higher than 7 t ha~(-1), whereas the yields in Southwest China(SWC), Northeast China(NEC), and the eastern part of Northwest China(NWC) were usually less than 6 t ha~(-1). The precentage of area having a relative yield above 0.70, 0.85, and 0.85 for N, P, and K fertilizers accounted for 52.3, 74.7, and 95.9%, respectively. Variation existed in N, P, and K fertilizer requirements, with a CV of 24.8, 23.9, and 29.9%, respectively, across all sites. More fertilizer was needed in NCC and the northern part of the MLYR than in other regions. The average fertilizer requirement was 162, 72, and 57 kg ha~(-1) for N, P_2O_5, and K_2O fertilizers, respectively, across all sites. The incorporation of the spatial variation of attainable yield and fertilizer requirements into wheat production practices would benefit sustainable wheat production and environmental safety. 相似文献
149.
The priority of management factors for reducing the yield gap of summer maize in the north of Huang-Huai-Hai region,China 下载免费PDF全文
Yue-e LIU Yu-xin LI Tian-fang LÜ Jin-feng XING Tian-jun XU Wan-tao CAI Yong ZHANG Jiu-ran ZHAO Rong-huan WANG 《农业科学学报》2021,20(2):450-459
Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. In this study, we conducted field experiments using different planting modes, which were basic productivity(CK), farmer practice(FP), high yield and high efficiency(HH), and super high yield(SH), to estimate the yield gap. Different factorial experiments(fertilizer, planting density, hybrids, and irrigation) were also conducted to evaluate the priority of individual management factors for reducing the yield gap between the different planting modes. We found significant differences between the maize yields of different planting modes. The treatments of CK, FP, HH, and SH achieved 54.26, 58.76, 65.77, and 71.99% of the yield potential, respectively. The yield gaps between three pairs: CK and FP, FP and HH, and HH and SH, were 0.76, 1.23 and 0.85 t ha~(–1), respectively. By further analyzing the priority of management factors for reducing the yield gap between FP and HH, as well as HH and SH, we found that the priorities of the management factors(contribution rates) were plant density(13.29%)fertilizer(11.95%)hybrids(8.19%)irrigation(4%) for FP to HH, and hybrids(8.94%)plant density(4.84%)fertilizer(1.91%) for HH to SH. Therefore, increasing the planting density of FP was the key factor for decreasing the yield gap between FP and HH, while choosing hybrids with density and lodging tolerance was the key factor for decreasing the yield gap between HH and SH. 相似文献
150.
Soil physical changes and maize growth in a structurally fragile tropical soil due to mulching and duration between irrigation intervals 下载免费PDF全文
E. G. Moura V. R. A. Macedo V. G. L. Sena L. S. Campos A. C. F. Aguiar 《Soil Use and Management》2017,33(4):631-638
Under tropical meteorological conditions, the volume of soil explored by plant roots is crucial for crop growth as it allows increased water and nutrient use efficiency. We hypothesized that, under different irrigation intervals, leguminous mulch can extend the duration between irrigation events but maintain crop performance, because decreased evaporative fluxes also reduce constraints to root exploration imposed by mechanical stress. We evaluated the combined effects of leguminous mulch and irrigation intervals on soil physical properties to determine whether the growth and productivity of maize were modified in a structurally fragile tropical soil. The experiment involved the following treatments: 4‐day irrigation intervals with soil mulched (4C) or bare (4S), 6‐day irrigation intervals with soil mulched (6C) or bare (6S), 8‐day irrigation intervals with soil mulched (8C) or bare (8S) and 10‐day irrigation intervals with soil mulched (10C) or bare (10S). Mulch decreased soil penetration resistance and increased to 4 days the favourable time for root development in drying soil. Relative to bare soil, mulch with a 6‐day irrigation interval almost doubled nitrogen uptake post‐tasselling, which decreased nitrogen remobilization and increased the crop growth rate during this stage. These conditions had a positive effect on the transpiration rate and stomatal conductance as well as on the growth and yield of maize. A 6‐day irrigation interval with mulch compared to 4 days with bare soil resulted in similar conditions for root development, but greater uptake of nitrogen (102.73–78.70 kg/ha) and better yield (6.2–5.3 t/ha), which means greater efficiency in nitrogen and water use. 相似文献