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1.
为探明在引黄灌区春小麦生产中减施化肥对土壤供氮与春小麦吸氮的影响,通过田间小区试验,分析不同氮、磷、钾用量对耕层土壤矿质态氮累积与春小麦氮素吸收利用的影响。结果表明:(1)施氮量120~180 kg·hm-2时,土壤矿质态氮累积量和植株氮素累积量最高为102.58 kg·hm-2和294.92 kg·hm-2,与常规施氮量(240 kg·hm-2)相比,氮素利用率、氮肥贡献率及氮肥农学效率均显著提高,增幅分别为138.97%、29.23%、136.35%,氮肥偏生产力和依存率降低至41.2 kg·kg-1和68.35%;籽粒产量增加3.54%~15.66%。可见,适量减氮有利于耕层土壤氮素矿化,促进氮向籽粒转移,提高氮肥利用率和籽粒产量。(2)从常规施磷量(120 kg·hm-2)减施至48~96 kg·hm-2时,土壤矿质态氮累积量和植株氮累积量均升高,最高为98.61 kg·hm-2和242.79 kg·hm...  相似文献   

2.
为探讨生物炭与灌水对春小麦产量和品质的综合效应,以北疆灌区春小麦为研究对象,通过随机区组试验,设置3个灌水量[4 500 m3·hm-2(W0)、4 050 m3·hm-2(W1)和3 600 m3·hm-2(W2)]和3个生物炭施用量[0 t·hm-2(B0)、10 t·hm-2(B1)和20 t·hm-2(B2)]水平,比较分析了不同生物炭用量与灌水量组合条件下春小麦干物质累积、产量和籽粒蛋白质含量等品质指标的差异,并运用基于熵值的DTOPSIS法进行综合效应评价。结果表明,不同灌水量条件下施用生物炭对春小麦干物质累积量影响均不显著,但可提升籽粒品质,灌水量和生物炭的交互作用对春小麦籽粒品质与产量的影响显著。在W0条件下春小麦籽粒蛋白含量随生物炭用量增加呈先升高后降低趋势,且所有施加生物炭处理的籽粒蛋白质含量均低于B0W0处理;W1条件下施加生物炭处理的籽粒蛋白质含量变化趋势与W0条件下...  相似文献   

3.
为探究冀东地区强筋小麦适宜施氮量,选用2个强筋小麦品种津农7号(氮高效型)和中麦998(氮低效型)为试验材料,设置0 kg·hm-2(N0)、180 kg·hm-2(N1)、210 kg·hm-2(N2)和240 kg·hm-2(N3)4个施氮量处理,研究施氮量对强筋小麦籽粒产量和干物质与氮素积累转运的影响。结果表明,在N0~N2处理范围内,2个强筋小麦品种的籽粒产量、花前干物质转运量和氮素转运量随施肥量增加均显著增加,N3处理下2品种的籽粒产量和花前氮素转运量较N2处理无显著变化,说明适量施氮可促进强筋小麦氮素转运与籽粒产量的提高。增加施氮量可促进花前干物质向籽粒的转运,津农7号的干物质转运率高于中麦998,2个品种的花后干物质对籽粒的贡献率为60.59%~77.16%,说明小麦籽粒产量主要来源于花后干物质积累。2个品种开花...  相似文献   

4.
为探索施氮量和种植密度互作对冬小麦品种石4366生长特性的影响,2020-2021年度在长期氮肥定位试验田通过裂区试验,设置4个施氮水平(施氮量分别为75 kg·hm-2、150 kg·hm-2、225kg·hm-2和300 kg·hm-2,分别用N75、N150、N225和N300表示)和5个种植密度水平(分别为225×104株·hm-2、300×104株·hm-2、375×104株·hm-2、450×104株·hm-2和525×104株·hm-2,分别用D225、D300、D375、D450和D525表示),比较分析了不同处理间该品种旗叶面积、穗部发育、群体动态、秸秆特性和产量的差异。结果表明,施氮量和种植密度对石4366群体、茎秆特性和产量均有显著影响。N75条件下穗长、总小穗...  相似文献   

5.
研究施氮量对蒜后直播棉产量、品质以及效益的影响,以期制定适宜的氮肥运筹策略。以早熟棉品种鲁棉532和鲁棉551为试验材料,采用裂区设计,研究施氮量(0 kg·hm-2、45 kg·hm-2、90 kg·hm-2和135 kg·hm-2)对蒜后直播棉生育期、农艺性状、产量、品质及效益的影响。结果表明:随着施氮量的增加,棉花生育期延长,株高增加,单株结铃数先升高后降低,第一果枝节位、单株果枝数、铃重和衣分随着施氮量的增加变化不明显。棉花产量随着施氮量的增加先升高后降低,在90 kg·hm-2处理下达到最高值,去除氮肥投入后的净收益与籽棉产量变化规律一致,纤维上半部平均长度随着施氮量的增加而降低,断裂比强度和马克隆值随着施氮量的增加呈先升高后降低的趋势。综合考虑棉花需氮情况及经济效益,施氮量90 kg·hm-2为鲁西南植棉区蒜后直播棉推荐氮肥施用量。  相似文献   

6.
为探讨氮肥减量配施生物炭对北疆灌区春小麦光合和干物质转运特性及产量的影响,通过田间试验,设置对照(不施氮,CK)、常规施氮(300 kg·hm-2、N1)、单施生物炭(20 t·hm-2、B)、常规施氮+生物炭(N1B)、减氮15%(255 kg·hm-2、N2 )、减氮15%+生物炭(N2B)、减氮30%(210 kg·hm-2、N3)、减氮30%+生物炭(N3B)8个处理,对比分析了不同处理间春小麦光合作用、干物质积累和转运及产量的差异。结果表明,与常规施氮相比,减氮(N2、N3)对春小麦光合作用、干物质积累和转运均无显著影响,但产量及其构成要素和氮肥农学利用效率随着施氮量的减少而降低,配施生物炭后上述各指标均显著提升。综合表现以减氮15%配施生物炭处理(N2B)效果最优。该处理下旗叶SPAD值和净光合速率处于较高水平,成熟期单茎干重、籽粒占单茎重比例、花前同化物对籽粒产量的贡献率分别为5.01 g、51.31%和18.03%;籽粒产量为8 301.35 kg·hm-2,较 CK及N1处理分别增产38.09%和18.11%;氮肥农学利用效率最高,为12.40 kg·kg-1。在本试验条件下,氮肥减量15%配施20 t·hm-2生物炭最有利于春小麦光合生产、干物质积累和转运及产量提升。  相似文献   

7.
为探究冀东地区强筋小麦适宜施氮量,以强筋小麦石优20号和中麦998为材料,通过大田试验设置0 kg·hm-2(N0)、180 kg·hm-2(N180)、210 kg·hm-2(N210)和240 kg·hm-2(N240) 4个施氮水平,分析了施氮量对强筋小麦光合、产量、蛋白质含量和加工品质的影响。结果表明,与N0处理相比,施氮后石优20号和中麦998的产量均在N240处理下增加显著,增幅分别为3.20%和13.95%。随施氮量的增加,小麦旗叶叶绿素含量和光合参数均呈先升后降趋势,且在花后15 d达到最大值。施氮对Fv/Fm影响较小,对ΦPSⅡ影响较明显。旗叶、籽粒内硝酸还原酶和谷氨酰胺合成酶均随施氮量的增加呈先升后降趋势。增施氮肥后籽粒蛋白组分中清蛋白、球蛋白比例下降,醇溶蛋白、谷蛋白比例上升,各组分...  相似文献   

8.
生物质炭配施氮肥对茶树生长及氮素利用率的影响   总被引:4,自引:0,他引:4  
通过水泥池小区试验,采用15N同位素示踪技术,研究了生物质炭配施氮肥对茶树生长及氮素利用率(茶树吸收、土壤氨挥发、N2O和土壤残留量)的影响。结果表明,与不施生物质炭且不施氮肥(B0N0)处理相比,施氮能促进茶树的生长发育,茶树株高、树幅和基部径粗均显著增加,茶叶增产68.06%~112.63%。生物质炭对茶叶产量的影响因施氮量而异,在不施氮(N0)和减量化施氮(N1)条件下,配施生物质炭处理茶叶产量增加8.82%和8.75%,而常规施氮(N2)条件下配施生物质炭处理茶叶产量略有降低,但差异均不显著。与B0N0处理相比,施氮处理土壤氨挥发和N2O排放量显著增加;在N1条件下,配施生物质炭(B1N1)处理氨挥发和N2O累积排放量分别降低了5.87%和4.99%;在N2条件下,配施生物质炭(B1N2)处理氨挥发和N2O累积排放量分别降低了9.97%和11.41%,B1N2处理氮素减排效果更好。与单施氮肥处理相比,配施生物质炭均能增加茶树各器官氮含量、15N丰度和Ndff值,有利于茶树对氮素的吸收利用。与单施氮肥处理相比,配施生物质炭处理茶树15N利用率和15N残留率分别增加了0.46~3.93百分点和4.09~14.37百分点,15N损失率下降4.54~18.30百分点,其中B1N1处理效果优于B1N2处理。总体而言,生物质炭配施氮肥促进了茶树对氮的吸收,增加土壤氮素持留,并降低氮素气态损失,从而提高了氮素利用率,以减量化施氮配施生物质炭(B1N1)处理茶树能起到“减氮增产”效果,具有良好的应用前景。  相似文献   

9.
为解决黄土高原半干旱区土壤贫瘠、氮肥固持率低及化肥不合理施用问题,以陇中春小麦为研究对象,比较分析了不同耕作[传统翻耕(CT)和免耕(NT)]和施肥方式[不施氮肥(CK)、单施化学氮肥(N)、单施有机肥(M)和氮肥有机肥配施(NM)]下春小麦氮素积累量、氮素利用效率和土壤硝态氮残留的差异。结果表明,NT-NM处理对各生育时期春小麦氮素积累具有显著的促进作用,使春小麦氮素偏生产力、氮素回收率、氮肥农学利用效率和氮素收获指数较CT-N处理分别提高了42.93%、20.13%、83.83%和2.55%;土壤硝态氮残留量表现为NM处理低于N和M处理、免耕处理低于翻耕处理,NT-NM处理下的0~100 cm土层土壤硝态氮残留较CT-N处理减少52.56 kg·hm-2;NT-NM处理优化了春小麦产量构成,提高了产量和生物量,其中产量达到了3 258.26 kg·hm-2,比CT-N处理显著增加56.21%,有效穗数和千粒重提高是其增产的主要原因。因此,免耕结合氮肥与有机肥配施可实现春小麦增产和氮素高效利用,同时降低氮素残留对农田生态系统的潜在危害,是黄...  相似文献   

10.
试验采用裂区试验设计,氮肥为主区,设置氮肥不同量级与生物炭配施;品种为副区,设氮高效和氮低效品种,分别为郑单958(ZD958)和先玉508(XY508),于大喇叭口期、吐丝期、灌浆期、乳熟期、腊熟期取样测定各器官鲜干重,测定氮含量用以计算氮素积累量、吸收效率、利用效率和氮效率。生物炭3000 kg/hm2与纯N 165 kg/hm2配施干物质积累、氮积累能力及氮效率均表现突出,生物炭3000 kg/hm2与纯N 210 kg/hm2配施产量表现最高,且显著高于生物炭3000 kg/hm2+纯N 165 kg/hm2处理。生物炭3000 kg/hm2与纯N 165 kg/hm2配合施用时,氮高效品种郑单958的干物质积累能力、氮积累能力、氮效率及产量均优于氮低效品种先玉508,且达到显著差异。在内蒙古平原灌区,生物炭与氮肥减量条件下,生物炭3000 kg/hm2与纯N 165~210 kg/hm2配施,可实现节氮30%~45%,氮高效玉米品种氮效率提升52.78%~93.33%,更能发挥氮高效品种较强的氮吸收能力和氮利用能力,利于实现高产、高效。  相似文献   

11.
介绍了我国麻类标准的现状。通过分析,指出了存在的问题,主要表现在标准体系不完善、标准更新不及时,协调性差及贯彻执行不力等。提出了我国麻类标准应采取的对策。  相似文献   

12.
2017—2018年,在同安镇粮食产能区示范推广水稻病虫害绿色防控与统防统治融合技术模式,取得了显著成效。融合技术示范区比常规区减少用药2~3次,用药量减少37.6%,防治成本降低400元/hm^2;水稻产量增加12.8%,收益增加2 835元/hm^2。  相似文献   

13.
Summary

Arbuscular mycorrhizae were inoculated into phosphorus-deficient soil fertilized with either organic or chemical fertilizer with cucumber (Cucumis sativus L.) as the first crop and lettuce (Lactu-ca sativa L.) as the second crop but without additional fertilization and AM inoculation. AM increased dry matter and fruit yield of cucumber significantly in the unfertilized, organic-fertilized and P-deficient plants compared with the fully chemical-fertilized plants. AM inoculation increased the available phosphorus in plant and soil by around 30% for all treatments except for those chemically-fertilized. The rate of AM infection did not differ significantly among the fertilization treatments, but the infection intensity was higher in unfertilized, organic-fertilized and phosphorus-deficient treatments than chemical-fertilized treatment. The residual effects of AM-inoculated to cucumber were evident for lettuce in all pre-treatments that were unfertilized and un-inoculated for the second cropping. Without P-fertilization, neither crop could grow optimally even when the soil was inoculated with AM, suggesting that AM could not serve as a substitute for phosphorus fertilizer. However, the other beneficial effects of AM on crop growth and yield could not be fulfilled with phosphorus fertilizer.  相似文献   

14.
百香果是海南省的新兴产业,也是我国多个省区扶贫攻坚的重要产业。病虫害是影响百香果产业的重要因素,随着海南百香果种植面积越来越大,病虫害对百香果产业的不利影响越来越凸显。由于缺乏百香果病虫害种类调查鉴定的基础性研究,许多种植户对田间发生的病虫害种类识别不足,从而影响了百香果病虫害的防控效果。为了摸清海南百香果种植区的病虫害种类,于2019—2021年对海南省儋州市、乐东县、屯昌县、文昌市、三亚市、东方市、保亭县、白沙县、海口市等百香果种植区的病虫害进行了系统调查与鉴定,并对其发生危害特点进行了研究。鉴定发现海南百香果种植区的病害有11种,分别是病毒病、茎基腐病、炭疽病、疮痂病、疫病、灰霉病、果腐病、褐斑病、烟煤病、藻斑病和缺镁。重要病害为病毒病和茎基腐病,危害程度分别为4级和3级,炭疽病和疮痂病危害也较重,危害程度均为2级,其他病害危害较轻。害虫有28种,分别是黄胸蓟马、茶黄蓟马、红带蓟马、美洲棘蓟马、普通大蓟马、咖啡木蠹蛾、美洲斑潜蝇、橘小实蝇、斜纹夜蛾、双线盗毒蛾、绿丽刺蛾、白带锯蛱蝶、烟粉虱、温室白粉虱、柑橘粉蚧、木槿曼粉蚧、藤壶蜡蚧、茶角盲蝽、樟颈曼盲蝽、稻绿蝽、中稻缘蝽、茶小绿叶蝉、丽球瓢蜡蝉、绿鳞象甲、眼斑芫菁、白条豆芫菁、甘薯梳龟甲和朱砂叶螨。重要害虫为黄胸蓟马和咖啡木蠹蛾,危害程度均为3级,茶黄蓟马和美洲斑潜蝇的危害也较重,危害程度均为2级,其他害虫危害较轻。软体动物3种,分别是灰巴蜗牛、同型巴蜗牛和一种尚未鉴定的蛞蝓。本研究明确了海南百香果种植区病虫害具体种类,新发现百香果病害1种和害虫24种,为海南百香果病虫害的精准防控提供技术支撑。  相似文献   

15.
为明确春季调控措施对冬小麦生长发育和籽粒产量的影响,以冬小麦品种石新828为材料进行田间试验,4个处理分别为:起身期追全部氮肥(除基肥外,下同)并叶面喷多效唑(N1);起身期追2/3氮肥并喷多效唑+拔节期追1/3氮肥(N2);起身期追1/3氮肥+拔节期追2/3氮肥(N3);拔节期追全部氮肥(N4)。生育期间测定群体和个体生育特性,成熟期调查产量性状。结果表明,N1和N2处理小麦拔节期的总茎数、叶面积指数(LAI)和干物质积累量均显著高于N4和N3处理。孕穗期N4和N3处理小麦的总茎数、LAI和干物质积累量显著高于N1和N2处理。开花到成熟期各处理的总茎数、LAI和干物质积累量差异均不显著。孕穗期前,不同处理的株高差异不显著,孕穗期后,N4处理的株高最高,且显著高于N1处理。各处理基部节间直径和中上部节间长的差异不显著,N4处理基部第一节间长度显著大于其他处理。随追氮时期前移或前期施氮量增多,不孕小穗数减少,结实小穗和穗粒数增加,N1比N4处理不孕小穗数显著减少,结实小穗和穗粒数显著增多。N1处理小麦成熟期的千粒重最高,且显著高于N4处理。N1处理的籽粒产量最高,且显著高于N3和N4处理。起身期追氮配合多效唑调控,可以获得比拔节期追氮更高的穗粒数和千粒重,从而获得更高的产量。  相似文献   

16.
Textile fibers were obtained from secondary polyethylene terephtalate (PET) and its mixtures with primary PET at initial orientation of 18000–33000 %, rate of additional orientation drawing 3.5–6.5 times and temperature of thermal fixation 363–413 K. The fibers’ tensile strength was found to decrease and elongation at break to increase with the decrease of their linear density under the conditions of fibers formation. For the fibers based on polymer mixtures, the presence of oxidized fragments in the secondary PET limited the compatibility of the two polymers which resulted in deteriorated tensile properties. The linear density (4–16 dtex), tensile strength (30–50 cN/tex) and elongation at break (20–60 %) of the PET fibers obtained were close to these for the industrially produced polymer fibers. The values of the average diameter of the fibers formed and oriented under laboratory conditions allows classifying them between the fine and the coarse textile fibers which makes them suitable for the textile industry.  相似文献   

17.
《Plant Production Science》2013,16(4):281-285
Abstract

Two cultivars of spinach and one cultivar of komatsuna were sand cultured using a nutrient solution with Na and K in various combinations. The growth (fresh weight of shoot) of spinach cv. Atlas was significantly increased when 1.4 mM KC1 of the 7 m M KO was replaced with 1.4 mM NaCl, although the growth was reduced when more KC1 was replaced with NaCl. In another spinach cv. All Right, however, NaCl substituting for 20% of KC1 showed no significant effects. In komatsuna, Na used in place of K at any ratio reduced the growth. The growth of spinach cv. Atlas was increased by applying 20 mM NaCl, irrespective of K dose (480 - 2400 mg K2O per 1/2000 a Wagner pot). The growth of spinach cv. All Right was also increased by 20 mM NaCl when K was at a deficient level (480 - 960 mg K20 per pot), but was not when K was at: an excessive level (1920 - 2400 mg K2O per pot). In komatsuna, 20 mM NaCl reduced the growth. In spinach, Na prevented the decrease of the photosynthetic rate and stomatal conductance caused by K deficiency.  相似文献   

18.
砂糖的含水量、装包温度和仓储条件对其贮存保质具有重要影响。本文从白砂糖的含水分特性、干燥机理和生产过程环节等对白砂糖干燥与冷却的影响进行深入分析。由于结晶过程的包裹现象,砂糖含水分可分为表面和内部水分,白砂糖干燥过程只能去除前者。生产过程中煮糖、分蜜操作对内部水分含量有影响。贮存过程的内部水分的扩散是砂糖降质的根本原因,而装包温度和贮存条件是影响内部水分扩散的外在条件。  相似文献   

19.
Gas-exchange characteristics of potato (Solanum tuberosum L.) canopies were determined with crop enclosures under condition of optimal water supply, during soil water depletion, and during recovery from drought-stress. The plants were grown under a rainshelter in large containers with 2-m2 surface area. Control plants received water throughout the growth period. In Expt. 1, transient drought was imposed by interrupting water supply completely for 22 days. During the 33-day period of drought treatment in Expt. 2, the stressed plants received half the amount of water that was given to the control plants (irrigations 2–3 times per week).

During soil water depletion, stomatal conductance of the canopy was reduced earlier and more than photosynthesis. This resulted in a lower internal carbon dioxide concentration in the leaves of stressed plants and a higher ratio between photosynthesis and stomatal conductance. The value of that ratio increased as soil water potential dropped.

Water-use efficiency ( ) increased during drought stress. The cultivar Bintje showed a larger ratio between photosynthesis and stomatal conductance of the canopy and a higher than cv. Saturna, both for optimal water supply and during drought stress.

Photosynthesis and conductance of the canopy started to recover immediately upon rewatering, even when relative values had declined to 20–30% during the preceding stress period. After release from stress, the leaves in the top layer of the canopy had a higher stomatal conductance in treated plants than in control plants.  相似文献   


20.
本文建立了气质联用仪测定稻田环境中苯醚甲环唑和嘧菌酯的残留分析方法,对苯醚甲环唑和嘧菌酯在水稻、土壤和田水中的消解动态和残留规律进行了研究。苯醚甲环唑和嘧菌酯在糙米、稻壳、植株、土壤和田水中的最低检测浓度均为0.20 mg/kg,最小检出量为0.2 ng,在不同样品中的平均加标回收率为80.8%~109.5%,相对标准偏差在1.7%~19.7%之间。田间试验结果表明,苯醚甲环唑和嘧菌酯在水稻植株和田水中的残留消解动态规律均符合一级动力学反应模型,苯醚甲环唑在水稻植株和田水中的残留消解半衰期分别为6.3~11.6 d和1.4~11.6 d;嘧菌酯在水稻植株和田水中的残留消解半衰期分别为3.6~8.7 d和2.9~23.1 d。以推荐剂量600 g/hm2和1.5倍推荐剂量900 g/hm2,最多施药3次,距最后一次施药15 d时,苯醚甲环唑和嘧菌酯在糙米中的最高残留量分别为0.461 mg/kg和0.634 mg/kg,低于我国国家标准《食品中农药最大残留限量》(GB2763-2014)中规定的糙米中苯醚甲环唑最大残留限量0.5 mg/kg和欧盟、美国规定的糙米中嘧菌酯最大残留限量5.0 mg/kg。  相似文献   

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