氮磷配施对夏玉米产量和叶片衰老特性的影响

氮和磷作为玉米生长发育的必需营养元素,对玉米产量的提高具有重要影响。本试验以登海111(Denghai111,DH111)为供试材料,在2020年和2021年分别设置11个氮磷配施处理和15个氮磷配施处理来探究氮磷配施对夏玉米叶片衰老特性和产量形成的影响。结果表明:在相同施磷水平下,随着施氮量增加,夏玉米的叶面积指数(leaf area index, LAI)、叶绿素相对含量(SPAD值)、抗氧化酶活性(超氧物歧化酶(superoxide dismutase, SOD)、过氧化物酶(peroxidase, POD)和过氧化氢酶(catalase, CAT)呈现先增加后降低的趋势,丙二醛(malondialdehyde, MDA)含量呈现先降低后增加的趋势,产量呈现先增加后降低的趋势。在N0～N2条件下,随施磷量增加,LAI、SPAD值、抗氧化酶活性呈现增加趋势, MDA含量呈现降低趋势,产量呈增加趋势;而在N3与N4条件下,随施磷量增加, LAI、SPAD值、抗氧化酶活性呈现先增加后降低的趋势, MDA含量呈现先降低后增加的趋势,产量呈现先增加后降低趋势。在2020年, N3 P1处理...     

种植密度对夏玉米碳氮代谢和氮利用率的影响

研究了低、中、高3个种植密度对夏播玉米CF008、郑单958和金海5号碳氮积累、运转及氮肥利用的影响, 以期通过密度调控碳氮代谢, 实现产量与氮肥效率协同提高。结果表明, 吐丝期茎叶总糖和全氮积累量和茎叶总糖和全氮的运转率均以中或高密度下较高, 而籽粒产量、氮素吸收效率、氮素利用效率和氮肥利用率均以中或低密度显著高于高密度。吐丝前地上部氮素积累量以中高密度下较高, 但成熟期地上部总氮量及籽粒氮量均以中低密度较高, 表明吐丝期后植株氮素积累量对玉米籽粒氮贡献较大。在中低密度下, 3个品种夏玉米产量达10 262~11 461 kg hm^-2, 氮肥利用率达23.00%~34.11%。     

基肥减氮对夏玉米品种产量形成和氮利用的影响

在氮肥追施时期和追施量相同的情况下,在基肥中设置不同的氮肥施用量,研究其对夏玉米生长发育、叶片功能、氮素吸收利用和产量的影响。结果表明,基肥中适当减少氮肥的施入量,能保证植株苗期正常的生长发育需求,花后叶面积和相对叶绿素含量与前期高氮处理差异不显著,保证了叶片的功能持续期,氮素吸收效率和氮肥偏生产力均显著高于基肥中高氮处理,两年规律一致,在节约肥料投入的同时,对群体产量没有显著影响。总施氮量在180kg/hm~2条件下,采取基肥、大口和吐丝期分别30、120和30kg/hm~2的施肥方式,与前期高氮相比可节省氮肥33%,是较为理想的氮素施用方式。     

玉米根系分泌碳、氮动态及与根系特征的关系

为深入认识玉米根系分泌碳、氮规律及其与根系特征的关系,以玉米品种'迪卡653'为材料,采用土培-水培相结合的方法,测定了玉米根系形态指标和根系分泌物中碳、氮的含量.结果表明,玉米根系碳、氮分泌比强度(EIroot-C、EIroot-N)在生育前期高于生育后期,与比根长、比根表面积、比根体积呈显著正线性相关,而与根系C/...     

在植株不同水平距离处垂直断根对夏玉米产量形成和籽粒库容特性的影响

以高产夏玉米品种郑单958(浅根型,ZD)和登海661(深根型,DH)为材料,于大喇叭口期(V12)分别在距离植株两侧10 cm、20 cm、30 cm处垂直断根,断根深度60 cm,以不断根处理为对照,共设计8个处理(ZDCK、ZD10、ZD20、ZD30;DHCK、DH10、DH20、DH30),研究了玉米植株两侧不同水平距离处根系对夏玉米籽粒灌浆及产量形成的调控作用。结果表明,ZD10、ZD20与DH10、DH20分别切断24.81%、11.69%与16.82%、7.52%的根系;ZD30与DH30各指标与CK间无显著差异,ZD10、ZD20产量分别下降13.09%、9.10%,显著大于DH10、DH20的产量降幅(9.81%、4.64%),其产量下降原因主要是断根后两品种的穗粒数与千粒重降低,其中ZD20、ZD10穗粒数与千粒重较ZDCK分别下降4.90%、5.60%和4.37%、7.88%,DH20、DH10穗粒数与千粒重较DHCK分别下降3.38%、5.15%和1.15%、4.97%;断根后两品种实际库容与结实率均有不同程度下降;到达最大灌浆速率时的天数(T_(max))、灌浆速率最大时的生长量(W_(max))、最大灌浆速率(G_(max))、籽粒灌浆活跃期(P)、灌浆速率也均下降,断根处理对浅根型品种郑单958的影响更为显著。     

施用氮锌肥对不同夏玉米品种干物质和氮锌元素累积分配的影响

研究施用氮锌肥下夏玉米植株干物质、氮锌元素累积和分配的变化,为锌肥的合理利用及肥料配施提供理论依据。采用再裂区设计,主因素为90,180,225 kg/hm² 3个施氮水平,副因素为0,4.5 kg/hm² ZnSO₄·7H₂O 2个喷锌处理,副副因素为郑单958和谷神玉66 2个玉米品种,大田条件下研究施用氮锌肥对不同玉米品种籽粒产量、植株干物质累积动态和各器官氮锌元素吸收、累积、分配的影响。结果表明,施氮量为180,225 kg/hm²下夏玉米籽粒产量分别达9.77,10.42 t/hm²,较90 kg/hm²处理平均增加18.0%;吐丝后以施氮量225 kg/hm²下干物质量较高,成熟期以90 kg/hm²处理的穗轴和籽粒干物质量分配比例较高。成熟期施氮量225 kg/hm²处理各器官中氮含量、茎中锌含量以及叶和籽粒氮、锌累积量均表现出优势,而90 kg/hm     

不同灌水施氮方式对玉米叶片生理特性和产量的影响

为了研究不同灌水施氮方式对玉米叶片生理特性、产量及其构成的影响。以春玉米‘宜单629’为供试材料,监测不同灌水方式下玉米生育期内的叶面积指数(LAI)、生理特性指标和籽粒产量。结果表明,与均匀灌水均匀施氮(CICN)相比,交替灌水均匀施氮(AICN)和交替灌水交替施氮水氮协同供应(AIANS)显著提高玉米抽雄期及以后第7、14、21、28和35天的LAI和叶绿素含量及抽雄期、灌浆期和乳熟期叶片的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性、可溶性蛋白含量、玉米行数、行粒数、穗粒数、千粒质量和籽粒产量(P<0.05),但显著降低相应生育期叶片的MDA、可溶性糖和脯氨酸含量(P<0.05)。可见,AICN和AIANS有利于提高玉米的LAI和抗氧化酶活性,改善活性氧产生与清除之间的关系,从而使玉米产量增加。     

种植方式与密度对夏玉米碳、氮代谢和氮利用效率的影响

在67500,82500株/hm2密度水平下,以常规等行距种植方式为对照,比较分析不同缩行宽带种植方式（三行一带、四行一带、五行一带）对夏玉米碳、氮代谢与氮素利用效率的影响。结果表明,缩行宽带种植方式成熟期地上部总氮累积量、氮收获指数均高于对照等行距种植方式,其中三行一带、四行一带、五行一带种植方式地上部总氮累积量分别高于对照16．2％,16．9％,20．0％。籽粒产量较等行距种植方式均有不同程度增加,并达到显著水平。本研究中,成熟期地上部总氮量、叶片氮转运量与籽粒产量呈显著正相关,说明成熟期较高的地上部总氮积累、叶片高氮转运量可促进籽粒产量提高。而成熟期叶片C/N与籽粒产量呈显著负相关,各处理中,三行一带种植方式在低密度和高密度条件下成熟期叶片C/N均最低,而对照等行距种植方式值最高。     

施氮对墨西哥玉米植株硝态氮累积及产量的影响

采用微区试验研究了2个施氮水平（中氮,300 kg/hm²;高氮,600 kg/hm²）下2种施肥方式（一次基施和平均3次分施）对墨西哥玉米（Euchlaena mexicana）植株硝态氮（NO₃^--N）累积及产量的影响。结果表明,墨西哥玉米叶片中NO₃^--N含量以新生叶较高,全展叶较低,老叶居中;茎鞘和根系的NO₃^--N含量在不同收获期表现为第一收获期低于叶片,第二期仅比新生叶低,第三期则高于叶片。随着收获次数增加,NO₃^--N含量在叶片中呈降低趋势,在茎鞘和根系中先降后升。高氮水平和分次施肥是造成同一类型叶片NO₃^--N累积的主要原因;高氮分次施肥处理（N_2-3）第二期收获的新生叶NO₃^--N含量最高,为92.66 μg/g,这一数值尚未达动物摄食的潜在致毒剂量。氮素用量增加,其生产效率降低,但高氮（600 kg/hm²）一次性基施处理的干物质产量和粗蛋白质产量均显著高于其他处理。综上所述,较高的氮肥用量一次性基施能够实现墨西哥玉米的高产且不会影响其产品安全性。     

An Analysis of Seasonal Effects on Leaf Nitrate Reductase Activity and Nitrogen Accumulation in Maize (Zea mays L.)

The important enzyme in nitrogen (N) assimilation, nitrate reductase (NR), is an inducible enzyme influenced by many external (light, temperature, etc.) and internal (genotype) factors. The efficiency of the N assimilation system may vary with genotype and season. In the present study, the effects of season on NR activity in relation to N accumulation in maize plants were investigated. Six different cultivars of maize, namely Ganga-11, Deccan-103, Hi-starch (hybrids), Arun, Manjari and Vijay (composites), were sown during the monsoon (88-day crop duration) and in winter (150-day crop duration). In vivo NR activity in the last fully expanded leaf (LFEL), and the N contents of the whole plant and the LFEL were estimated at seven phenological growth stages. Three different states of N metabolism in maize, namely (i) low NR activity per unit leaf area per unit time coinciding with high accumulation of N, (ii) high NR activity coinciding with low N accumulation, and (iii) low NR activity coinciding with low N accumulation, were noted. These results clearly demonstrate that the relationships between N uptake and accumulation parameters change with the season and crop growth stage and are subject to a genotypic influence. Thus it is necessary to evaluate genotypes under similar environments to select a genotype with high N use efficiency. As these relationships are growth dependent, care must be taken to evaluate them at a particular phenological stage rather than on the basis of days after sowing.     

Effects of Two Planting Systems on Soil Structure and Root Growth of Maize (Zea mays L.)

In 1994 two planting systems of maize—rotary hoe-sowing (RS) and plough (2 diskings) sowing (PDS)—were compared in the field with respect to their influence on the root growth of maize and on selected physical properties. Roots were sampled at the five-leaf stage (S:5) and the milk stage of the maize seeds (S:MS).
Generally, in the PDS planting system the roots were richer compared to the RS. At the S:5 stage the correlation coefficient between the physical properties and the toot system was considerably higher, while at the S:MS stage the corresponding correlation coefficient was much lower.
In the RS planting system, at 15 cm and 30 cm distances from the sowing rows, far fewer roots were observed than in the PDS one.     

Effect of Mulch from Selected Multipurpose Trees (MPTs) on Growth, Nitrogen Nutrition and Yield of Maize (Zea mays L.)

Leaf extracts and mulch from 14 multipurpose trees were used to test their effects on maize germination, growth and yield. Maize germination was significantly reduced by leaf extracts of all species with increasing extract concentration. The most drastic reductions were caused by Gliricidia sepium , Tetrapleura tetraptera , Lonchocarpus sireceus , Senna siamea and Leucaena leucocephala . Terminalia superba , Tetrapleura tetraptera , Pithecelobium dulce , Gliricidia sepium and Senna siamea significantly reduced maize root growth at the lowest extract concentration, while shoot length was most significantly reduced by Gliricidia sepium , Leucaena leucocephala , Alchornea coordifolia , Pithecelobium dulce , Terminalia superba , and Tetrapleura tetraptera at all concentrations. Growth of maize in pots and yield in the field were controlled by nitrogen supply and uptake. Fast-decomposing leaf material rich in nitrogen promoted growth and yield of maize. Thus Leucaena leucocephala and Gliricidia sepium , both nitrogen-fixing legumes with high nitrogen contents and fast-decomposing leaf materials, significantly increased maize growth and yield. This suggests that the negative effects of leaf extracts observed in the laboratory are ecologically irrelevant in the field.     

乙矮合剂对不同密度夏玉米花粒期叶片氮素同化与早衰的影响

为探讨乙矮合剂调控夏玉米氮素同化和防止后期早衰的生理机制,为建立华北夏玉米区密植高产稳产化学调控技术提供理论依据,2013—2014年在中国农业科学院新乡试验站,以中单909和浚单20为材料,设置乙矮合剂(ECK)和密度梯度处理,研究密度梯度对花后玉米穗位叶氮同化特征和早衰的影响,以及ECK的化学调控效应。结果表明,灌浆期(花后0~40 d),穗位叶硝酸还原酶(NR)活性和谷氨酰胺合成酶(GS)活性随密度增加而显著下降;灌浆后期(花后30~40 d),谷草转氨酶(GOT)和谷丙转氨酶(GPT)活性随种植密度增加而显著降低。穗位叶叶绿素相对含量、可溶性蛋白含量和游离氨基酸含量在灌浆中后期(花后20~40 d)随种植密度增加而显著降低;两品种产量在7.5万株hm–2密度达最大值,7.5~10.5万株hm–2密度群体产量下降,高密群体易发生早衰。ECK处理显著提高了各密度群体灌浆中后期(花后20~40 d)穗位叶NR活性、GS活性、游离氨基酸含量、可溶性蛋白含量和叶绿素含量;显著提高了高密群体(7.5~10.5万株hm–2)GOT活性和GPT活性;较高密群体下(7.5~10.5万株hm–2),中单909和浚单20较各自对照的增产幅度分别为5.59%~6.63%和6.73%~8.10%。ECK处理提高了高密群体夏玉米穗位叶片氮代谢关键酶活性及其产物含量,保证密植群体氮代谢正常进行,有效防止早衰及提高产量。综上所述,采用合理的种植密度并结合喷施乙矮合剂可作为华北夏玉米区高产栽培的重要技术措施。     

肥料类型及用量对玉米产量形成及氮肥效率的影响

【研究目的】研究了不同施氮量下,普通尿素和包膜复合肥对夏玉米氮肥效率和产量的影响;【方法】采用随机区组设计5个施氮水平,研究不同类型尿素对夏玉米干物质量、籽粒灌浆速率、氮肥效率和产量的影响,讨论氮肥效率与产量的关系;【结果】与普通尿素相比,相同施氮水平下,包膜复合肥处理玉米干物质量和籽粒灌浆速率均显著提高,玉米籽粒产量比普通尿素平均提高6.9%。包膜复合肥处理的氮肥农学利用率（AE）和偏生产力（PFP）比普通尿素平均分别提高6.6%和9.8%。包膜复合肥施用量较高时对产量、AE和PFP的增加效果更显著;【结论】与常规尿素相比,包膜复合肥可显著提高籽粒产量和氮肥效率,其原因是提高了玉米花后干物质积累和籽粒灌浆速率。随着包膜复合肥产量的增加和成本的降低,它在粮食作物生产上应用前景非常广阔。     

弱光胁迫对不同基因型玉米籽粒发育和碳氮代谢的影响

以不耐阴型玉米豫玉22和耐阴型玉米郑单958为试验材料,设置自然光照和弱光胁迫2个处理,研究弱光胁迫对不同基因型玉米籽粒建成和碳氮代谢的影响,探求弱光胁迫下碳氮代谢与籽粒建成的关系。结果表明,弱光胁迫下,玉米籽粒生长发育减缓,败育数增加,体积和干重降低;果穗顶部籽粒可溶性糖、蔗糖含量和全氮含量升高, 淀粉含量和碳氮比降低;豫玉22胚乳细胞中淀粉粒密度降低,郑单958与对照相近。弱光胁迫下,不耐阴型玉米豫玉22果穗籽粒的生长发育减缓程度大于耐阴型玉米郑单958,同一基因型果穗顶部籽粒生长发育减缓程度大于中部籽粒,耐阴型玉米郑单958在恢复自然光照后籽粒体积、干重、籽粒碳氮含量和碳氮比与对照之间的差异均小于豫玉22,表现出更强的补偿效应。淀粉合成能力和碳氮比的下降可能是弱光胁迫条件下籽粒发育不良以致最终造成败育的主要原因。     

Effect of Planting Date on Time and Rate of Nitrogen Accumulation by Maize (Zea mays L.)1

Effects of environment on time and rate of nutrient accumulation by crops affects fertilizer nutrient use efficiency. The effect of planting date on rate, time and amount of nitrogen (N) accumulated by maize from a Hamerly cl soil (Aeric Calciaquoll) was examined with and without supplemental irrigation. Maize was planted on three dates spaced at 2-to 3-week, intervals; the earliest planting date was 1 May in 1984 and 1985. N accumulation was examined as uni- and diphasic tanh[k(time)] functions and solved for total N accumulation at harvest, time of maximum N accumulation rate and the time coefficient of N accumulation. A diphasic function, which indicates two periods of intense N accumulation, provided the closest agreement with observed N accumulation. As planting was delayed, time required to reach maximum N accumulation rates, τ (uniphasic) or τ₁ and τ₂ (diphasic), decreased from an average of nearly 75 to 42 days (uniphasic) and from nearly 65 to 35 days and 100 to 75 days after planting for τ₁ and τ₂, respectively. Maximum N accumulation rates increase from about 59 to 75 mg N plant^?1 day^?1 (uniphasic) or 35 to 65 mg N plant^?1 day^?1 and 20 to 70 mg N plant^?1 day^?1 for the first and second maxima in the diphasic model, respectively. Average maximum total N accumulation ranged from 2.85 g N plant^?1 for early plantings to 1.5 g N plant^?1 for plantings made on 25 June. The time coefficient, k (uniphasic) or k₁ (diphasic), tended to increase from average values of about 0.04 to > 0.09 day^?1 for k and from about 0.04 to > 0.105 day^?1 for k₁. The second time coefficient, k₂, of the diphasic function varied widely between about 0.075 to > 0.12 day^?1 and showed complex relationships with planting date. Periods of N accumulation shortened and intensity of N accumulation increased as the time coefficient increased.     

控释肥对夏玉米产量和氮素积累与分配的影响

在大田条件下研究树脂包膜控释肥(CRF)和硫包膜控释肥(SCF)对夏玉米花后光合产物和氮素积累与分配及产量的影响。结果表明,花后控释肥处理的光合速率始终较高,在相同施肥量(N、P、K量相同)情况下,控释肥CRF(1428kghm-2)和SCF(1668kghm-2)及其减量25%处理的单株干物质和氮素积累量都显著高于等量普通复合肥(CCF,1260kghm-2)处理;控释肥减量25%时,干物质向籽粒中的分配比例显著高于CCF处理;成熟期籽粒的氮素积累,控释肥处理都显著高于CCF处理,并随着控释肥比例的增加而增加,全量与减量25%的处理无显著差异。控释肥能显著提高玉米产量,等量控释肥增产13.15%和14.15%;控释肥减量25%时,分别比CCF增产9.69%和10.04%;其氮肥利用率和农学效率也均显著高于普通肥处理。     

缓释肥施用量对超高产夏玉米氮素积累分配的影响

明确缓释肥施用量对超高产夏玉米氮素积累和分配的影响及其对产量形成的作用。以‘苏玉29’‘、苏玉30’为材料,采用裂区设计,设置7个缓释肥水平（N0、270、315、360、405、450、495kg/hm²）,研究夏玉米氮素积累和分配在不同处理下的变化趋势。结果表明：随着缓释肥施用量增加,两品种（‘苏玉29’、‘苏玉30’）氮素积累量与氮素利用效率均呈单峰变化趋势,在N405kg/hm²水平下达最大值,且‘苏玉29’氮素利用率显著高于‘苏玉30’。百千克籽粒需氮量随缓释肥施用量增加先升后降,在N405kg/hm²水平下达最大值,而每千克氮生产籽粒量的变化规律相反。随着施氮水平提升,玉米偏生产力降低。最高产处理下,茎、叶、鞘氮素转移率和对籽粒产量的贡献率显著高于其他处理。回归分析表明,成熟期叶片中氮素分配比例较高有利于‘苏玉29’高产,苞叶和穗轴中氮素分配比例较高有利于‘苏玉30’高产。在本实验条件下,两品种在N405kg/hm²时产量最高,氮素积累量、氮肥利用率和百千克籽粒需氮量最高,茎、叶、鞘的氮素转移率及其对产量的贡献率较高。     

Direct and Residual Contributions of Symbiotic Nitrogen Fixation by Legumes to the Yield and Nitrogen Uptake of Maize (Zea mays L.) in the Nigerian Savannah

Field experiments were conducted to determine the direct and residual contributions of legumes to the yield and nitrogen (N) uptake of maize during the wet seasons of 1994 and 1995 at the University Farm, Abubakar Tafawa Balewa University, Bauchi, Nigeria, located in the Northern Guinea savannah of Nigeria. Nodulating soybean, lablab, green gram and black gram contributed to the yield and N uptake of maize either intercropped with the legumes or grown after legumes as a sole crop. Direct transfer of N from the nodulating soybean, lablab, green gram and black gram to the intercropped maize was 24.9–28.1, 23.8–29.2, 19.7–22.1 and 18.4–18.6 kg N ha^–1, respectively. However, the transfer of residual N from these legumes to the succeeding maize crop was 18.4–20.0, 19.5–29.9, 12.0–13.7 and 9.3–10.3 kg N ha^–1, respectively. Four years of continuous lablab cropping resulted in yields and N uptake of the succeeding maize crop grown without fertilizer N that were comparable to the yields and N uptake of the succeeding maize crop supplied with 40–45 kg N ha^–1 and grown after 4 years of continuous sorghum cropping. It may therefore be concluded that nodulating soybean, lablab, green gram and black gram may be either intercropped or grown in rotation with cereals in order to economize the use of fertilizer N for maize production in the Nigerian savannah.