种植密度对冀中南地区不同夏玉米品种LAI和灌浆特性的影响

为明确不同种植密度下玉米品种各生育时期群体叶面积指数(LAI)和籽粒灌浆之间的关系,揭示不同密度对群体LAI和灌浆特性的调控机制。选用冀中南地区3个高产玉米品种,研究了6种种植密度对不同生育时期群体LAI和灌浆特性的影响。结果表明:3个品种LAI在整个生育期内均呈先升高后下降的趋势,在吐丝期达到顶峰,吐丝期以后开始下降。3个品种各生育时期LAI均随密度的增加而升高,在相同的密度水平下,衡玉1182群体LAI要大于郑单958和先玉335,表现出较强的耐密性。玉米产量与LAI呈二次函数关系,郑单958、先玉335和衡玉1182最适LAI分别为3.252,3.193,4.125。3个品种吐丝期最大LAI与种植密度均呈极显著相关,最大LAI随密度增加而直线增加。3个品种玉米籽粒的百粒质量均随灌浆进程呈现出慢-快-慢"S"形变化,各品种籽粒灌浆速率在整个籽粒发育过程中呈单峰抛物线型变化,最大灌浆速率出现在授粉后30 d左右,不同品种各处理最大灌浆速率均表现为低密度中密度高密度,且低密度籽粒灌浆速率要高于中、高密度。在达到最大灌浆速率后,衡玉1182灌浆速率下降速度要快于郑单958和先玉335。各密度下群体籽粒灌浆过程均可用Logistic方程模拟,将各品种灌浆过程划分为粒重渐增期、线性灌浆期和缓增期,相同密度水平下,衡玉1182籽粒灌浆速率最高峰值(Gmax)和籽粒灌浆速率平均值(Gmean)要大于郑单958和先玉335,活跃灌浆期(D)则小于郑单958和先玉335,3个品种不同灌浆时期平均灌浆速率表现为衡玉1182先玉335郑单958。3个品种随着种植密度的增加,穗长、穗粗、行粒数、穗行数和千粒质量均表现下降的趋势,秃尖呈现上升的趋势。衡玉1182是在82 500株/hm2时达到了产量的最大值,郑单958和先玉335种植密度是75 000株/hm2时产量最大,最大产量3个品种表现为衡玉1182先玉335郑单958。     

玉米生产上3个主推品种光合特性、干物质积累转运及灌浆特性

以当前玉米生产主推品种郑单958、先玉335和京科968为试验材料, 考察其光合特性、干物质积累与转运及籽粒灌浆特性, 以揭示高产玉米品种的产量形成特性, 为玉米高产生产提供依据。结果表明: (1)产量以京科968最高、先玉335次之、郑单958最低, 京科968分别较郑单958和先玉335高14.55%和7.93%。(2)穗位叶净光合速率和冠层光合能力表现为京科968>先玉335>郑单958, 且吐丝期>乳熟期。京科968吐丝期和乳熟期的穗位叶净光合速率分别比先玉335高7.84%和16.78%, 比郑单958高22.23%和24.44%; 冠层光合能力分别较先玉335高38.77%和58.41%, 较郑单958高50.83%和56.49%。(3)花后干物质积累量、转移量、干物质转运率和干物质转运对籽粒贡献率均以京科968最高, 分别比先玉335高13.72%、21.20%、6.32%和4.77%, 比郑单958高31.87%、39.96%、18.49%和10.42%。(4)籽粒灌浆参数在不同品种间存在较大差异, 京科968与先玉335的平均灌浆速率(0.73和0.75 g 100-grain^-1 d^-1)相当, 且均高于郑单958 (0.67 g 100-grain^-1 d^-1); 活跃灌浆期以郑单958 (53.69 d)最长、京科968 (51.02 d)次之、先玉335 (48.95 d)最短。(5)相关分析表明, 产量与净光合速率显著正相关, 与花后干物质积累量及转运率极显著正相关。京科968具有较高的光合效率、花后干物质积累量及转运率、灌浆速率及较长的灌浆持续期, 是较郑单958和先玉335高产的重要原因。     

密植对不同玉米品种产量性能的影响及其耐密性分析

提高种植密度是玉米高产的重要措施之一,并且群体密度对冠层光合特性与产量有重要影响,为阐明不同基因型玉米品种的耐密性,本研究以先玉335、郑单958、吉单209为供试品种,设置60 000株 hm^-2、75 000株 hm^-2、90 000株 hm^-2、105 000株 hm^-2 4种密度处理,测定并计算6个生育期的叶面积指数(LAI)、光合势(LAD)、净同化率(NAR)以及产量性能参数平均叶面积指数(MLAI)、平均净同化率(MNAR)、收获指数(HI)、单位面积穗数(EN)、单穗粒数(GN)、千粒重(GW),并结合产量性能参数的变化对各品种进行耐密性分析。结果表明,不同品种产量性能参数对密度胁迫的反应相同,MLAI、EN与密度呈显著正相关,MNAR、HI、GN、GW与密度呈显著负相关;各品种产量对密度的响应呈一元二次方程关系,并具有良好的相关性;在试验密度范围内,品种耐密性表现以先玉335最好、郑单958次之,吉单209较差,其中,先玉335的适宜密度范围为90 000~105 000株 hm^-2,郑单958与吉单209的适宜密度范围为75 000~90 000株 hm^-2。     

黑龙江春玉米种植区高产品种籽粒灌浆、脱水特性及产量分析

为了研究不同高产玉米品种在黑龙江春玉米区种植的可行性,以‘先玉335’和‘郑单958’为试材,通过对比分析,探讨2个品种在该地区种植的灌浆和脱水特性。结果表明,‘先玉335’灌浆迅速,生理性脱水快,产量高;‘郑单958’灌浆持续期略长,前期和中期灌浆速率较‘先玉335’慢,但后期灌浆速率和自然性脱水速率都快,产量较高。从气温和降雨特点来看,在黑龙江春玉米种植区部分积温较高地区,可考虑将‘郑单958’作为品种更替及多样化的备选材料。     

穗期高温对玉米子粒灌浆生理及产量的影响

为揭示玉米穗期高温胁迫对子粒灌浆生理及产量的影响,以耐热型玉米品种郑单958和热敏感型玉米品种先玉335为试验材料,研究了第9片叶完全展开至抽雄期高温对玉米子粒灌浆特性、淀粉合成酶活性、激素含量和产量的影响。结果表明,穗期高温处理,郑单958和先玉335的产量分别比对照降低了11.14%和25.40%;2个品种的粒重和灌浆前期的灌浆速率降低,到达最大灌浆速率的时间延迟,灌浆速率最大时的生长量减小,活跃灌浆期延长;灌浆前期子粒淀粉合成酶活性降低;高温对先玉335的影响明显高于对郑单958。高温处理后,2个品种子粒中的生长素、玉米素核苷和赤霉素含量变化趋势一致,均表现为灌浆初期降低,灌浆后期升高,脱落酸含量表现则相反。     

郑单958与先玉335黄淮海北部物候期特点分析

【研究目的】为了实时掌握夏玉米在黄淮海北部生长发育进程,综合评价环境因素对玉米生长发育的影响,调查分析了郑单958与先玉335在北纬37°53′、东经115°42′的物候期特征。夏播玉米郑单958与先玉335播种后6d出苗,生育期间为111d,灌浆期持续66d,叶片展开速率和灌浆速率随温度升高而加速,收获前6d（10月5-11日期间）,郑单958与先玉335产量贡献率分别达6.61%和4.20%。【结论】分析结果认为,黄淮海区域属于一年两熟种植模式,黄淮海北部夏玉米一般不能达到完熟收获。选用中早熟品种,及早抢播、适时晚收,保证玉米充足的有效积温和授粉后充足的灌浆时间可以显著提高玉米产量。     

不同生育时期玉米苞叶叶绿素荧光特性差异分析

以郑单958和农大364两个玉米品种为研究材料,对大田条件下不同生育时期玉米苞叶的叶绿素含量和叶绿素荧光动力学进行了比较分析.结果表明,不同生育时期玉米苞叶叶绿素含量呈先升后降的变化趋势,并在灌浆期达到最高值,且农大364苞叶的叶绿素降低速率要低于郑单958,这样有利于其保持更为持久的光合能力.不同生育时期玉米品种间苞叶叶绿素荧光参数(Fm、Fv、Fv/Fm、Fv/Fo等)的变化规律基本一致,郑单958高于农大364,说明郑单958苞叶反应中心活性较高,具有较高的电子传递速率,并且苞叶叶片开放的PSⅡ反应中心捕获激发能的效率高于后者.     

种植密度对玉米先玉335和郑单958生理特性、产量的影响

在河北省太行山山前平原条件下,通过大田试验研究了不同种植密度对玉米先玉335和郑单958生理特性和产量的影响。结果表明,随着种植密度增加,叶绿素相对含量降低,叶面积指数(LAI)增大,群体光合势增加,群体干物质积累量呈现升高趋势,但单株干物质积累则呈现降低趋势;产量呈现先增后降趋势。玉米群体和个体的产量性状相对较为协调的种植密度为:先玉335为7.5万株/hm2、郑单958为6万株/hm2。     

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。     

沈糯6号的籽粒产量及相关生理指标研究

以郑单958为对照,在5个密度下对沈糯6号进行籽粒产量、冠层结构和生理指标的比较研究。结果表明:在75 000株/hm2密度下沈糯6号的籽粒产量可达7 122.5 kg/hm2,与郑单958的最高产量差异不显著;相同密度下沈糯6号的生物产量、叶面积指数较低,但在较高密度下收获指数和灌浆后期最大叶面积指数持续时间大于郑单958;叶绿素含量与郑单958没有明显差异;5个密度下光合速率均高于郑单958,并受密度压力的影响明显小于郑单958;在67 500~82 500株/hm2高密度下,沈糯6号灌浆期穗位下部冠层透光率比郑单958要高,良好的通透性可能是光合速率和叶面积指数优于郑单958的主要原因。     

Effects of Population Density on the Vegetative Growth of Leafy Reduced-stature Maize in Short-season Areas

Maize hybrids which produce more leaves above the ear, with leaf area indices similar to conventional hybrids, which require fewer corn heat units to flowering and maturity, and tolerate higher population densities, should be better adapted for production in short season areas than currently available hybrids. Leafy reduced-stature maize hybrids, which have only recently been developed, have traits which address these criteria. The objective of this study was to evaluate the effects of different population densities (50 000, 100 000, 150 000, and 200 000 plants.ha⁻¹) on the vegetative growth of one leafy reduced-stature (LRS), one non-leafy reduced-stature (NLRS), and two conventional control hybrids (Pioneer 3979, < 2500 CHU, and Pioneer 3902, 2600–2700 CHU) at two locations. There were no differences among population densities for leaf number above the ear; however leaf area index increased as population density increased for all hybrids. The LRS hybrid had a greater average leaf number above the ear (2.7 and 2.0 more leaves than NLRS and the control hybrids, respectively). As a result the leaf area index value of LRS was much greater than the NLRS and similar to the conventional hybrids, but LRS matured substantially before the conventional hybrids. The LRS hybrid required fewer corn heat units to reach flowering and maturity and had more time for grain filling than the conventional hybrids. Therefore, LRS hybrids show promise for production in short season areas where maize cultivation is not economical due to shortness of growing season.     

高油玉米杂交种品质及其花粉直感效应的稳定性分析

为探讨环境对高油玉米品质的影响,以100个高油玉米杂交种和200个高油花粉直感的当代组合为材料,对品质性状的稳定性进行了分析。结果表明,高油玉米杂交种组合在不同年份和不同地点间的含油量差异平均为1.00%,最小为0.17%,最大相差可达1.91%,不同组合间油分变化有一定差异,即不同品种在油分性状表现的稳定性上存在差异。年份和地点效应对蛋白质含量影响的程度接近,不同年份和地点间的最大差异在1.00%左右;年份间的淀粉差异在0.4%左右,地点间的差异在1.7%左右,而单个组合在不同年份和不同地点间籽粒淀粉含量的最大差异则达到5.81%。普通玉米籽粒高油花粉直感后,在地点和年份间油分变化最大的组合其油分变化达到1.88%,最小的组合为0.37%,总体平均为1.00%;单个组合的蛋白质含量在不同年份和不同地点间的最大差异达到3.37%,最小为0.61%,总体平均为1.78%;单个组合的淀粉含量在不同年份和地点间最大相差6.21%,变化最小的组合相差0.71%,所有组合平均为2.95%。     

紫玉米不同组配方式的花青素含量及产量比较

以18个玉米自交系组配成的16个紫玉米杂交组合为试验材料,研究不同组配方式配制的紫玉米籽粒、穗轴、苞叶、雄穗花青素含量及花青素产量。结果表明:(1)不同组配方式的紫玉米籽粒花青素含量、籽粒产量及籽粒花青素产量差异均较大。深紫玉米×深紫玉米,花青素含量最高;深紫非糯玉米×糯玉米,籽粒产量最高;深紫玉米×深紫玉米,籽粒花青素产量最高。(2)深紫玉米×深紫玉米,穗轴花青素含量、花青素产量最高;非紫苞叶×深紫苞叶,紫玉米苞叶花青素含量、花青素产量最高;非紫雄穗×深紫雄穗,紫玉米雄穗花青素含量、花青素产量最高。(3)穗轴花青素含量与籽粒花青素含量呈极显著正相关;雄穗花青素含量与苞叶花青素含量呈极显著正相关。(4)紫玉米花青素总产量(籽粒、穗轴、苞叶、雄穗)为:深紫×深紫>深紫×浅紫>非紫×深紫>浅紫×非紫;籽粒花青素产量对总花青素产量贡献最大。     

Effects of Population Density and Planting Pattern on the Yield and Yield Components of Leafy Reduced-Stature Maize in a Short-Season Area

Maize hybrids that yield well, mature earlier with low grain moisture contents, tolerate higher population densities and take advantage of narrow row spacings better than the currently available hybrids would be more suitable for production in short-season areas. Leafy reduced-stature maize hybrids, which have only recently been developed, have traits which address these criteria. The objective of this study was to evaluate the effects of different population densities (65 000 and 130000 plants ha^?1) and planting patterns (single rows 76 cm apart and paired rows with 20 cm between rows within a pair of 56 cm between rows of adjacent pairs) on the yield and yield components of two leafy reduced-stature (LRS1 and LRS2), one non-leafy reduced-stature (NLRS), and two conventional corn hybrids (Pioneer 3979, < 2500 CHU; and Pioneer 3902, 2600-2700 CHU) at two locations. All hybrids had higher kernel numbers per row and single plant grain yields at the lower population densities when in paired rows. However, as plant density increased, these variables decreased more in the conventional hybrids than the LRS and NLRS hybrids, which demonstrates the greater tolerance of the latter to the stresses associated with higher plant densities. Grain yield was higher for the two LRS hybrids and the NLRS hybrid at 130000 plants ha^?1 than 65 000 plants ha^?1 Grain yield of conventional hybrids was reduced at the higher population density. The LRS hybrids matured before both conventional hybrids and out yielded Pioneer 3979 at the higher plant population density in both row spacings at both sites. Harvest index was not affected by population density and this value was not different among the NLRS and conventional hybrids. However, the harvest index of the LRS hybrids was greater than the others. LRS and NLRS hybrids had lower moisture contents and earlier maturities than conventional hybrids. Rapid growth of the first ear and higher harvest index values might are indications that LRS hybrids are more tolerant of higher population densities than the conventional hybrids.     

不同熟期夏玉米品种籽粒灌浆与脱水特性及其密度效应

研究不同熟期夏玉米品种籽粒灌浆与脱水特性及种植密度的调控作用, 以期为黄淮海地区夏玉米籽粒机收提供科学依据。2016—2017年在山东农业大学玉米科技创新园, 种植早熟玉米品种登海518 (DH518)、衡早8号(HZ8)和中晚熟玉米品种郑单958 (ZD958)、登海605 (DH605), 设60 000、75 000、90 000株 hm ^-23个种植密度。结果表明, 早熟品种DH518、HZ8较中晚熟品种ZD958、DH605灌浆期短, 产量低。4个品种生理成熟时的籽粒含水率与其生育期相关性不显著, 早熟品种籽粒后期脱水速率快, DH518和HZ8从籽粒达最大含水量到生理成熟的脱水速率均值较ZD958和DH605两年分别高0.015% °C ^-1和0.014% °C ^-1。相关性分析显示, 籽粒脱水速率与灌浆速率相关性不显著, 生育后期籽粒含水率与茎鞘、叶片含水率呈显著正相关, 与苞叶、穗轴含水率呈极显著正相关。随种植密度的增加, 不同品种籽粒灌浆期缩短, 平均灌浆速率降低, 籽粒生理成熟时的含水率降低。合理增加种植密度能够显著提高不同熟期夏玉米品种的产量。     

青贮玉米秸秆中性洗涤纤维与蔗糖合成酶活性之间的关系

摘要：以十个秸秆中性洗涤纤维（NDF）含量差异明显的青贮玉米杂交组合为材料,研究了生育时期青贮玉米蔗糖合成酶活性与秸秆NDF含量之间的关系。为改善青贮玉米NDF含量,育成低纤维高品质青贮玉米品种提供理论依据。结果表明,不同青贮玉米组合的秸秆NDF含量与蔗糖合成酶活性有关,且秸秆NDF含量与蔗糖合成酶活性成负相关。验证了蔗糖合成酶作为纤维素合成的关键酶,通过将蔗糖分解为UDPG,为纤维素合成提供直接底物的规律。     

Response of Corn Hybrids Differing in Canopy Architecture to Chemical and Mechanical (Rotary Hoeing) Weed Control: Morphology and Yield

Weed interference with the growth and yield of corn plants is affected by both mechanical and chemical means of weed control. Recently, corn hybrids accumulating more leaf area, maturing earlier, yielding better in narrower row spacings and tolerating higher plant populations better than conventional hybrids have been developed. Because of more rapid leaf area accumulation during the earliest stages of canopy development and overall canopy architecture, they may be more susceptible to damage due to mechanical weed control. The objective of this study was to assess the response of corn hybrids with a wide range of canopy architectures to chemical and mechanical (rotary hoeing) weed control, with an emphasis on quantifying morphology and grain yield responses. Field experiments were conducted in 1997 and 1998 at Ste. Anne de Bellevue, Quebec. Three hybrids were tested: leafy reduced-stature (LRS1 and LRS2), and the conventional hybrid Pioneer 3979 (P3979). Rotary hoeing alone had very little effect, while herbicide application reduced the interference of weeds with growth and grain yield of all hybrids. Hybrid P3979 had more total leaf area than LRS1 and LRS2, but the percentage of leaf area above the ear was much higher for LRS hybrids (70 %) than for P3979 (51 %). Generally, LRS hybrids were much shorter with more leaf area above the ear than P3979, contributing to the large differences in canopy architecture between the LRS hybrids and P3979. However, morphology and grain yield response of hybrids to rotary hoeing and herbicide weed control was not different, indicating that the new hybrids were not more susceptible to damage caused by mechanical weed control than a corn hybrid with a conventional canopy architecture.     

Alternate Row Spacing and Plant Density Effects on Forage and Dry Matter Yield of Corn Hybrids (Zea mays L.)

Irrigated field experiments were conducted in the Marmara region of Turkey in 2002 and 2003 to compare alternate 40 : 25 cm row spacings and conventional 65 cm with four different plant densities (65 000, 85 000, 105 000 and 125 000 plants ha⁻¹) of three corn hybrids (DK-585, ADA 95–10 and C-955) in some morphological traits and forage and dry matter yield. Morphological traits such as plant height, leaf per plant, stem diameter, ear per plant and ear percentage were measured, forage and dry matter yield was also determined in this study. Hybrids, row spacings and plant densities significantly affected some morphological traits, forage and dry matter yield at 0.01 level. Later maturing hybrids tended to produce taller and thicker stemmed plants. Row spacings and plant densities did not affect plant height. Average stem diameter increased significantly with population density. Row spacings did not influence leaf number, whereas leaf number increased slightly with plant density. On average, all corn plants had slightly more than 1.0 ear per plant in our experiment. Row spacings and plant densities did not affect significantly number of ear per plant. Early maturing DK-585 had the highest ear percentage whilst late maturing C-955 lowest. Yields usually increased with hybrid maturity. When averaged across years, row spacings and plant densities, late maturing C-955 performed significantly better in forage and dry matter yield in all experimental years and combined years. The studies showed favourable advantage for alternate 40 : 25 cm rows over conventional 65 cm row spacings at all plant densities. Average forage and dry matter yields were greater for alternate 40 : 25 cm row spacings than for 65 cm row spacings. However, strong hybrid × row spacing interactions for both forage and dry matter yield were detected.     

利用清蛋白PAGE技术鉴定甜玉米杂交种初报

利用改进的聚丙烯酰胺凝胶电泳技术对7个甜玉米杂交种的清蛋白进行分析。结果表明,甜玉米种子清蛋白存在一定的多态性,每个品种都有各自独特的清蛋白PAGE“指纹”。利用该技术对7个不同甜玉米杂交种的种子纯度进行了室内检验,同时利用田间种植鉴定法进行了测定,通过对其中5个杂交种的电泳纯度和田间纯度进行相关分析,二者达显著水平（r=0.9408）,说明改进的聚丙烯酰胺凝胶电泳技术用于甜玉米种子纯度鉴定是可行的,可用于甜玉米杂交种纯度鉴定。