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1.
脲酶抑制剂与硝化抑制剂对稻田土壤氮素转化的影响 总被引：10，自引：0，他引：10
【目的】本研究旨在阐明脲酶抑制剂(urease inhibitor,UI)和硝化抑制剂(nitrification inhibitor,NI)对稻田土壤氮素转化的影响,探讨抑制剂提高稻谷产量以及氮肥利用率的机理。【方法】本试验设在我国南方红壤稻田,共5个处理:1)不施氮肥(CK);2)尿素(U);3)尿素+脲酶抑制剂(U+UI);4)尿素+硝化抑制剂(U+NI);5)尿素+脲酶抑制剂+硝化抑制剂(U+UI+NI);脲酶抑制剂采用N-丁基硫代磷酰三胺(NBPT),硝化抑制剂采用3,4-二甲基吡唑磷酸盐(DMPP)。在水稻分蘖期和孕穗期测定土壤脲酶活性、硝酸还原酶活性、土壤铵态氮含量、硝态氮含量以及微生物碳、氮的含量,分析NBPT与DMPP对水稻两个主要生育期土壤氮素供应的影响,比较各处理的产量以及氮肥利用率,通过逐步回归分析研究以上各指标对产量的影响,探明脲酶抑制剂NBPT与硝化抑制剂DMPP在稻田的增效机理。【结果】1)与单施尿素相比,添加NBPT以及NBPT与DMPP配施均显著提高稻谷产量与地上部氮素回收率,两个处理分别增产6.56%与8.24%,氮素回收率提高幅度为19.4%与23.7%。2)与单施尿素相比,添加NBPT以及NBPT与DMPP配施,显著降低水稻分蘖期的土壤脲酶活性和铵态氮含量,显著提高孕穗期的铵态氮含量,而对此时期的脲酶活性无显著影响,所有处理对两个时期的硝态氮含量、硝酸还原酶活性、微生物量碳、氮含量均无显著影响;因此,NBPT对于抑制脲酶活性以及提高铵态氮含量的作用主要在孕穗期之前,而单施DMPP没有显著效应。3)从各项土壤指标与水稻产量相关性的逐步回归分析结果来看,水稻分蘖期与孕穗期稻田土壤中铵态氮含量对水稻产量影响显著,而且孕穗期的影响大于分蘖期,其余指标则对产量无显著影响。【结论】脲酶抑制剂NBPT以及NBPT与硝化抑制剂DMPP配施显著提高孕穗期土壤中的铵态氮含量,显著提高稻谷产量以及地上部氮素回收率,证明了生产上氮肥后移的重要意义。 相似文献
2.
生化抑制剂是调控土壤氮素转化与提高氮肥利用率的有效途径之一。为明确生化抑制剂对沿淮稻茬小麦的效应,以淮麦38为供试品种,在安徽怀远县稻茬麦田设不施氮肥（CK）、尿素（U）、尿素+脲酶抑制剂NBPT（UN）、尿素+硝化抑制剂DMPP（UD）、尿素+硝化抑制剂NBPT+脲酶抑制剂DMPP(UND)共5个处理,研究了脲酶抑制剂NBPT（N-丁基硫代磷酰三胺）、硝化抑制剂DMPP（3、4-二甲基吡唑磷酸盐）及其两者组合对稻茬小麦产量及构成因子、氮素利用效率和土壤氮素的影响。结果表明,与U处理相比,UD和UND处理显著提高稻茬小麦产量、植株吸氮量和氮肥利用率;UD和UND处理分别增产8.9%和10.7%,穗数和穗粒数同步提高是其增产的主要原因,UN处理产量增加不显著;UD和UND处理氮肥农学利用率、氮肥吸收利用率、氮素吸收效率和氮肥偏生产力显著提高,氮收获指数无显著变化;UD和UND处理降低了小麦收获后耕层土壤无机氮的残留量,显著提高了微生物量氮的含量。综上,在沿淮地区稻茬小麦种植中,尿素配施DMPP或者配施DMPP+NBPT可以有效增加小麦产量,提高氮素利用效率。 相似文献
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在内蒙古科尔沁区农业高新科技示范园区,以常规追施尿素为对照,研究浅埋滴灌减施尿素配施尿素硝酸铵溶液（UAN）对春玉米根系、产量及效益的影响。结果表明,适量减施尿素配施UAN能促进玉米根系生长,增强吐丝期和乳熟期根系超氧化物歧化酶（SOD）、过氧化物酶（POD）酶活性,降低丙二醛（MDA）含量,延缓根系的衰老,有利于生育后期产量的形成。各土层土壤铵态氮及硝态氮含量均表现为CK （常规追施尿素）显著高于尿素减量配施UAN处理,UAN能促进根系对土壤氮的吸收利用。减施尿素25%、配施UAN 75 kg/hm2处理（N2U）产量与CK差异不显著,且显著高于减施尿素51%、配施UAN 75kg/hm2（N1U）处理;N2U处理两年的经济效益均最高。浅埋滴灌技术为尿素减量配施UAN玉米的田间作业提供便利,配施UAN、减施尿素是西辽河平原灌区春玉米减氮增效的有效途径。 相似文献
5.
On acid soils, no-tillage farmers are often advised to apply lime to the soil surface without incorporation by tillage. As such, it can take a number of years before the subsoil acidity is decreased. However, no-tillage seeders vary in the level of soil disturbance caused during seed placement. The consequence of such variations in soil disturbance for the effectiveness of lime in no-tillage cropping has not been explored. Our objectives were (i) to determine if the liming effect could be accelerated by increasing the rate of lime and level of soil disturbance during no-tillage seeding, and (ii) evaluate the effect of no-tillage seeding method, rate of lime and soil pH on yield of wheat, barley, canola and lupins. Three trials, each with a factorial design consisting of four seeding methods and four lime rates, were established in 1999 and continued until 2005. The soil had a texture contrast with about 15-20 cm of sand over yellow sandy clay loam and the initial pH (CaCl2) at both 0-10 and 10-20 cm was between 4.5 and 4.7. The four seeding treatments were: low disturbance zero-till disc openers (ZT), higher disturbance no-tillage tines with narrow knife-points (NT), higher disturbance full cut seeding with sweeps (FC) for the first three years followed by ZT from then on, and FC for the first year followed by NT thereafter. The four lime rates were 0, 1, 2 and 4 t ha−1.The liming effect was more rapid with the higher disturbance seeding of NT, FCZT and FCNT, compared with ZT; the seeding effect on soil pH diminished with time and was not detected in the subsoil after four years. Higher rates of lime increased this effect and there was no interaction between seeding method and lime rate. This indicated that soil pH under the different seeding methods responded in a similar manner to increased lime. Nonetheless, significant positive linear regressions were found between yield and soil pH for wheat and barley and a negative relationship for lupins. Canola showed no response to soil pH, possibly because establishment was affected by seeding method, and soil pH was not low enough to elicit a response. The ZT seeding method gave lower yields than the other methods for canola and lupins in some years, but had no effect on wheat and barley yields. Higher disturbance at the time of no-till seeding can, therefore, accelerate the liming effect, making earlier economic gains possible. 相似文献
6.
《Journal of Crop Improvement》2013,27(1):55-78
Abstract Beneficial effects of foliar N application to cereal crops have been widely believed to rely on subsequent rainfall or irrigation in the semi-arid region where in-crop rain is insufficient and unreliable. To verify this, factors contributing to the effects of foliar N application were assessed by implementing foliar N application in trials on three farmers' properties in central Queensland, Australia. Solutions of CRN35 (30 kg N ha?1 at 1.94 N % w v_1), urea and UAN (both 26, 2.25%), and urea (20, 20%; 40, 20%) and UAN (20, 20%; 40, 40%), were applied to wheat at anthesis respectively at the three properties (sites). Adjuvant chemical agents were also applied in mixture form with the N at the latter two sites. At the first site, with foliar N (CRN35) application, grain protein content on average increased by 1.07 percentage points, and by 1.6 in the presence of basal superphosphate. Superphosphate alone also increased grain yield. At the second site, while the applications of UAN and urea increased grain protein content by 1.3 and 0.9 percentage points, respectively, UAN showed superiority to urea in N recovery. At the third site, foliar N applications with or without chemical adjuvant did not affect grain protein content, but due to the higher concentration in the N solution, some of them (excluding UAN40) had negative effects on grain yield, compared to the water only control. Based on our data and supporting literature, to ensure the positive effect on wheat grain protein content, subsequent irrigation or rainfall may not be critical provided that foliar N concentration is lower than 5%. It is also suggested that UAN is superior to urea as an N source for foliar application. For alkaline/sodic soils, while the application of basal superphosphate increased grain yield, the added foliar N ensured an increase of grain protein content. 相似文献
7.
稻田脲酶抑制剂的应用效果及其与环境条件的关系 总被引：2，自引：0，他引：2
施用脲酶抑制剂可以抑制土壤中脲酶活性,延缓尿素水解速率,从而达到调控氮素,提高氮素利用效率的目的。为了提高脲酶抑制剂的应用效果和完善配套施用技术,我们于1988～1990年对几种抑制剂在不同环境条件下的施用效果进行了室内模拟试验和田间应用效果的初步研究。 相似文献
8.
【目的】添加生化抑制剂是提高水稻肥料利用率的有效途径之一。本研究旨在结合不同施肥模式揭示其节肥增效的群体优势,寻找适合黄泥田地区水稻高产高效的施用方式。【方法】采用二因素随机区组设计,研究生化抑制剂组合与施肥模式(一次性和分次施肥)互作对黄泥田水稻群体质量的影响。【结果】尿素分次施用处理水稻有效茎蘖数、有效叶面积指数(LAI)、抽穗至成熟期干物质积累量、抽穗期SPAD值和籽粒产量较一次性施用处理分别显著提高0.8%、24.0%、9.3%、1.5%和14.2%。不同施肥模式下,配施生化抑制剂组合N-丁基硫代磷酰三胺/N-丙基硫代磷酰三胺+2-氯-6-(三氯甲基)吡啶(NBPT/NPPT+CP)显著提高水稻有效茎蘖数及茎蘖成穗率,增加抽穗后干物质积累量,增大有效LAI,增加抽穗期SPAD值,提高水稻粒叶比,改善源库关系。相关性分析表明,抽穗至成熟期干物质累积与水稻籽粒产量呈显著正相关。新型脲酶抑制剂N-丙基硫代磷酰三胺(NPPT)单独施用及与2-氯-6-(三氯甲基)吡啶(CP)配施的水稻群体质量与N-丁基硫代磷酰三胺(NBPT)相似。【结论】通过施肥技术和抑制剂配施的集成与优化,可以改善黄泥田水稻群体质量,提高光合产物转化,获得更高产量。 相似文献
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10.
《Plant Production Science》2013,16(3):253-259
AbstractPhysical and chemical properties of vegetable oils and consequently their use, depend on the composition of fatty acids that accumulate in storage lipids during seed development. The objective of this study was to determine the combined effects of seed development stages and organic matter content of soil on oil fatty acid composition of canola. The experiments were carried out under field conditions on four soils with different organic matter contents. To evaluate seed oil content and fatty acid composition of canola, we harvested plants at six growth stages (GS), GS 75, GS 79, GS 83, GS 87, GS 92 and GS 99 including development of seed, ripening and senescence. The synthesis of oil and fatty acids were largely influenced by seed maturity and soil type. Seeds had maximum content of stearic and palmitic acids at GS 75 (50% of pods reach final size). The seed yield, oil content of seeds and oleic acid percentage of seed oil significantly increased with increasing rate of soil organic matter in canola. This study addresses the organic matter content in poor soils should be ameliorated not only to obtain higher crop yields but also quality production. 相似文献
11.
Establishment of seedlings of Bromus inermis , a native grass species of China, into a degraded steppe grassland was studied in an experiment with a factorial combination of different soil disturbance (control and harrowing), cutting post-sowing (control and cutting), nitrogen (N) fertilizer application (0 and 100 kg KNO3 hm−2 ) and seed rate (400, 800 and 1200 seeds m−2 ) treatments. Seedling emergence and survival rates, and plant performance, were followed over 2 years. Seedling emergence was increased by soil disturbance (harrowing). Cutting post-sowing and N fertilizer application did not increase seedling emergence. Seedling survival rates at the end of first growing season were strongly influenced by harrowing and the use of higher seed rates. Seedling height was higher in the harrowing and the N fertilizer application treatments and at the higher seed rates. Seedling survival rates in the second growing season were low but much higher with harrowing than the other treatments. Soil disturbance by harrowing may have increased contact between seed and soil, and reduced competition from established plants. It is concluded that, for the restoration of degraded semi-arid grassland in China by re-seeding, soil surface disturbance is necessary for successful seedling establishment, and modest seeding rates should be used to control costs. 相似文献
12.
Canola seedling blight, caused by Rhizoctonia solani, and Fusarium spp., can result in large yield losses to canola (Brassica napus) at high inoculum pressure. The effect of inoculum density was studied by mixing different amounts of R. solani AG-2-1 and Fusarium avenaceum into a sterilized natural soil and soil-less mix (2:1, v:v) separately, and recording seedling emergence, damping-off and seedling height within ten days after seeding; root rot severity at 12 days after seeding and seed yield at harvest on canola cultivars ‘45H29’ and ‘73-77RR’. Root rot severity increased and emergence, plant height and seed yield decreased with increased inoculum density of both R. solani and F. avenaceum. For quantification of R. solani AG-2-1, a primer and TaqMan probe set (Rs21F/Rs21R/Rs21P) was designed based on the nuclear ribosomal internal transcribed spacer (ITS) region of R. solani AG-2-1. From a conventional PCR amplification, an 88-bp product was amplified from all isolates classified as AG-2-1 with the primers Rs21F and Rs21R. No product was amplified with DNA from isolates belonging to other anastomosis groups of R. solani, other pathogens or the host plant. By using quantitative PCR, DNA amounts as low as 100 fg of R. solani AG-2-1 were detected. The quantity of DNA from soil samples with different inoculum densities estimated using qPCR was highly correlated to the number of colony-forming units (cfu) obtained from the same soil samples for both R. solani AG-2-1 and F. avenaceum. 相似文献
13.
苗期渍水对直播冬油菜产量和农学利用率的影响及油菜在不同氮肥施用下的响应 总被引：1，自引：0，他引：1
在轻简化施肥背景下,为减少渍害损失,解决长江流域冬油菜产区生产面临的重要问题,开展氮肥施用
对油菜渍害的缓解作用研究。设置三因素田间试验,分别为不同氮肥用量（0、60、120、180、240和300 kg N/hm2）、氮
肥类型（油菜专用控释尿素和普通尿素）和水分处理（苗期渍水和正常排水）,测定各处理产量和氮肥农学利用率,
明确苗期渍水对不同氮素供应水平油菜的影响,并比较油菜专用控释尿素一次性施用和普通尿素分次施用下油菜
对苗期渍水的响应。结果表明,直播冬油菜产量随氮肥施用量增加而提高,至240 kg N/hm2时不再增加。油菜专用
控释尿素一次性施用,在氮肥用量为60～180 kg N/hm2时产量高于普通尿素分次施用;在氮肥用量为240～300 kg
N/hm2时,两种氮肥类型产量基本相当。氮肥施用通过增加收获密度、单株角果数和每角粒数提高产量。苗期渍水
导致直播冬油菜产量损失1.1%～41.9%,随氮肥用量增加,渍水引起的产量损失率呈先增加后降低趋势。0～60 kg
N/hm2处理时,渍水使收获密度显著降低（降幅达29.4%~45.0%）,单株角果数增加;施氮量为120~180 kg N/hm2时,
渍水导致收获密度和单株角果数分别降低19.5%~33.7%和1.4%~17.7%;施氮高于180 kg N/hm2时,收获密度和单
株角果数降幅减小（降幅分别为5%~30.9%和3.6%~9.5%）。普通尿素分次施用和油菜专用控释尿素一次性施用,
分别在施氮量为120和180 kg N/hm2时产量损失率最高,分别达29.8%和41.9%。相同氮肥用量下油菜专用控释尿
素一次性施用的产量损失率大于普通尿素分次施用。渍水显著降低氮肥农学利用率,降幅为8.4%～51.9%,施氮充
足（240～300 kg N/hm2）时氮肥农学利用率降幅低于氮素用量较低处理（120～180 kg N/hm2）,油菜专用控释尿素一
次施用处理的农学利用率平均降幅（36.5%）高于普通尿素分次施用（17.3%）。综上可知,苗期渍水时,油菜专用控
释尿素一次施用,会加重油菜受渍影响;土壤氮素供应能力较低时,渍害逆境解除后,适量追施速效氮肥可有效缓
解产量损失,实现油菜稳产。 相似文献
14.
水稻基质育秧不同播种量对秧苗素质和产量的影响 总被引：5，自引：0，他引：5
为探索有机基质料培育标准化壮秧技术,以武运粳23号和＂科杰＂牌基质为材料,采用田间试验方法,研究了5种不同播种量水平对水稻秧苗地上部与地下部性状、大田茎蘖动态及产量的影响。结果表明,随着播种量增加,秧苗地上部和地下部性状差异较大,在播种量为120-210 g/盘范围内,叶绿素含量、盘结力和根系活力则随着播种量增加而增加,在播种量为150-180 g/盘时基质料育出的秧苗更有利于培育健壮的机插秧苗,具体表现为增穗、增粒作用,可以在大面积范围内推广应用。 相似文献
15.
Safflower (Carthamus tinctorius L.) is a deep-rooted crop which can tolerate water stress and can be grown in rotation with other crop species. Nitrogen is very important for the growth and yield of safflower, however, the effect of N level on chlorophyll content, assimilation rate, transpiration rate, stomatal conductance, substomatal CO2 concentration, and water use efficiency (WUE) have not been determined. A 2-year field study was conducted with the objective to determine the effect of N fertilization on yield, yield components, chlorophyll content, photosynthetic characteristics, and WUE of safflower grown under rainfed conditions. Three rates of N were used (0, 100, and 200 kg N ha−1) and two hybrids (CW9048 and CW9050). N fertilization increased seed yield by an average of 19%, the seed weight per plant by 60%, the seed weight per head by 18%, the number of heads per plant by 32%, and the number of seeds per plant by 41% compared with the control. N level also affected chlorophyll content, N concentration at anthesis, protein, and oil yield. N application increased assimilation rate by an average of 51%, stomatal conductance of water vapour by an average of 27%, and WUE by an average of 60% over the 2 years of the study when compared to the control. The present study indicates that N fertilization can affect yield, yield components, photosynthetic efficiency, and physiology of safflower under rainfed conditions. 相似文献
16.
通过两年田间定位试验,探讨脲酶/硝化抑制剂配施氮肥在黑土区玉米体系中的氨减排及氮素增效效果。设置两种耕作模式(条耕和旋耕)和3种氮肥类型(常规尿素、添加脲酶抑制剂尿素、添加硝化抑制剂尿素)。结果表明,条耕产量和氮素利用率分别为8 631 kg/hm2和33.4%,明显低于旋耕;氨挥发总量为20.6 kg/hm2,明显高于旋耕。脲酶/硝化抑制剂配施氮肥的产量和氮素利用率分别为10 737 kg/hm2和46.0%,较常规尿素分别提高25.6%和23.6%;土壤氨挥发累积量为18.6 kg/hm2,明显低于常规尿素。抑制剂类型显著影响氨排放,添加脲酶抑制剂尿素低于添加硝化抑制剂尿素。相同氮素投入条件下,添加脲酶/硝化抑制剂尿素在土壤条耕和旋耕模式下均可实现增产增效及氨减排效果,且添加脲酶抑制剂尿素具有较好的氨减排效果。 相似文献
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优质油菜中油杂8号施用氮磷硼肥的产量和品质效应 总被引：31，自引：3，他引：31
双低油菜新品种中油杂8号施用氮磷硼肥的田间试验结果显示,苗期、抽薹期、成熟期的干物重都有增加,以抽薹期至成熟期的干物重增加最为显著,表明施用氮磷硼肥的作用主要是促进油菜后期的生长发育,显著增加分枝数、角果数和单株粒重;以氮磷和氮磷硼处理增加幅度最大.不同施肥处理均显著增加籽粒产量,增产幅度为12.1%～30.5%,增产效果顺序为:N＞P＞B,以配合施用的增产效果最佳,NP、NB、NPB处理分别增产30.5%、29.3%、28.5%.增施B可提高菜籽油分含量,而N、P及NP配合施用则可提高蛋白质含量,降低油分含量.增施B还可提高油酸、亚油酸含量,降低芥酸和硫甙含量.同时对中油杂8号施肥增产和提高品质成分的原因进行了分析讨论,提出了增施硼肥和氮磷硼配合施用是保证中油杂8号高产高油优质特性充分发挥的技术关键. 相似文献
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Annual ryegrass (Lolium multiflorum Lam.) is a primary forage resource for livestock producers throughout the south‐eastern USA during the winter‐growing season. It is important for livestock producers to begin grazing annual ryegrass as early as possible and any management practices maximizing early season production could be beneficial. To assess the impact of seeding rate on subsequent yield, yield distribution, quality, seedling density, and end‐of‐season plant and tiller density, a 2‐year study was initiated at four locations in Louisiana. Three annual ryegrass cultivars, varying in seed size, were established at four seeding rates based on pure live seed (PLS) rates of 400, 800, 1200 and 1600 PLS m?2. There was no advantage in total yield from increasing seeding rates beyond 800 PLS m?2. However, first‐harvest yields increased from 360 to 930 kg dry matter (DM) ha?1 as seeding rate increased from 400 to 1600 PLS m?2. Crude protein and neutral‐detergent fibre concentrations, and in vitro DM digestibility, were not affected by seeding rate. Seedling density and end‐of‐season plant numbers increased as seeding rate increased. However, stems per plant decreased as seeding rate increased, indicating compensatory tillering for the reduced plant numbers observed at the lower seeding rates. These results indicate first‐harvest yield can be increased by planting at higher seeding rates but total yields are not increased. 相似文献
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为油菜生产的提质增效,探究含钾有机水溶肥对油菜生长发育及产量构成的影响,以甘蓝型油菜旺城油8号为材料,采用双因素随机区组设计,设置3个喷施时期（苗期、花期、苗期+花期）和5个含钾有机水溶肥施用量（0、375、750、1125、1500 g/hm2）处理,调查油菜产量性状。结果发现,在苗期或初花期喷施750 g/hm2的含钾有机水溶肥,油菜的株高、根颈粗、生物量等指标较对照组显著增加,两个时期均喷施的处理其促进效果更优。在苗期和初花期均喷施750 g/hm2水溶肥,增加了单株有效角果数和每角粒数,显著提高油菜产量,较对照增加39.07%,产油量增加44.22%。认为可通过在油菜苗期和初花期每公顷各喷施750 g的含钾有机水溶肥,促进油菜的生长发育,提高菜籽产量,增加产油量,提升经济效益。 相似文献