为了探明不同调控措施对热敏感型玉米花期高温热害的缓解作用,寻找缓解夏玉米花期高温胁迫的合适途径,选用热敏感型玉米品种'登海605'为试验材料,设置了高温(CK)、高温灌水(T1)、高温喷施叶面肥(T2)、高温喷施芸薹素内酯(T3)、高温'登海605'与'伟科702'混作(T4)共5个处理,调查不同调控措施对玉米花期高温胁迫下玉米株高、穗位高、穗位叶叶绿素含量、花丝长度和产量、相关性状的影响.结果表明:玉米花期高温胁迫下灌水能够降低果穗秃尖长度,增加果穗穗行数和行粒数,提高百粒质量和结实率,产量比对照增加28.38％;喷施叶面肥、芸薹素内酯都能够增加穗行数,提高结实率,产量比对照分别增加6.96％、5.96％;'登海605'与'伟科702'混作能够降低秃尖长,增加百粒质量,提高结实率,产量比对照增加8.34％.各处理效果:灌水＞混作＞喷施叶面肥＞喷施芸薹素内酯.灌水是缓解花期高温热害对热敏感型玉米产生不利影响的最有效措施,而在水资源缺乏的地区可采取耐热性互补的品种混作、喷施叶面肥和喷施芸薹素内酯的措施.

在玉米生产中存在投工较多、劳动强度较大、劳动效率较低等问题.通过实施品种筛选、播种带旋耕灭茬、混合施肥、单粒精播、节水灌溉、病虫草害防治、适时晚收等夏玉米轻简化生产技术,可减少种子、化肥、农药投入,减轻劳动强度,提高劳动效率,增加农民收入,实现节本增效.

为了利用杂种优势改良玉米品种的耐阴性,以10个耐阴性不同的玉米自交系为亲本,按照NCII4×6遗传交配设计,对遮阴和自然光照下玉米的产量及穗部性状的配合力、遗传参数进行分析.结果表明,产量、穗长、秃尖长、穗粗、穗行数、行粒数和百粒重7个性状在自然光照和遮阴处理下差异均达极显著水平,遮阴处理下昌改3、R2005、LYM35、LYM10这4个自交系的一般配合力较高,特殊配合力也较高,杂种优势也强,可作为玉米耐阴性遗传改良的候选亲本.LYM35x昌改3在遮阴处理下的特殊配合力效应值较高,在遮阴处理下表现优异,是耐阴性较强的组合.遗传参数分析表明,产量、穗长、穗粗、秃尖长和穗行数在遮阴处理下的狭义遗传力相对较高,可以在早代进行耐阴选择,行粒数和百粒重的狭义遗传力较低,广义遗传力较高,应在育种高世代进行选择.

为了探究Myf6基因在京海黄鸡和金茅黄鸡体内的差异表达规律,研究其在两个品种鸡中可能发挥的作用机制,试验采用实时荧光定量PCR技术对Myf6基因在不同品种鸡不同组织中的表达情况进行了检测.结果表明:京海黄鸡和金茅黄鸡公母鸡胸肌和腿肌中的Myf6基因相对表达量均比较高,且极显著高于脾脏(P＜0.01);京海黄鸡心脏组织中的Myf6基因相对表达量显著高于脾脏(P＜0.05),金茅黄鸡心脏组织中的相对表达量极显著高于脾脏(P＜0.01);两个品种鸡的其余组织中Myf6基因相对表达量与脾脏相比差异不显著(P＞0.05).京海黄鸡公母鸡胸肌和腿肌组织中Myf6基因的表达规律基本一致,仅在4周龄胸肌组织中有稍微下降的趋势,但总体上呈现上升的趋势;腿肌组织中的相对表达量比较稳定,从0周龄到16周龄呈现上升趋势,16周龄时达到最高水平.金茅花鸡公母鸡胸肌和腿肌组织中Myf6基因的相对表达量从0周龄到4周龄呈上升趋势,8周龄有稍微下降的趋势,之后又呈现上升的趋势.在两个品种中,无论是公鸡还是母鸡,胸肌中Myf6基因的相对表达量始终显著高于腿肌(P＜0.05).说明Myf6基因参与了肌肉的生长发育,并且发挥了不可替代的作用.

以40份玉米国内骨干自交系为材料,苗期利用遮光度为50％遮阳网人工模拟寡照环境,测定叶绿素(SPAD值)、生物量(地上部干重、根干重)、根冠比、株高等指标.结果表明,遮阴条件下地上部干重、根干重、根冠比受到严重影响,对根系影响最大,根干重与地上部干重和根冠比呈极显著正相关;主成分分析表明,5项耐阴指标简化可得到2个主成分,其贡献率分别为50.047％、24.615％.利用隶属函数法将40份玉米自交系划分为3类:耐阴性强(8份)、中等耐阴(17分)、耐阴性弱(15份),其中昌7-2为耐阴性最强自交系;塘四平头(SPT)、PB类群耐阴性好,PA、BSSS、旅大红骨(LRC)类群为中等耐阴,而兰卡斯特(Lanc)类群耐阴性差.

ABSTRACT: The responses of two maize (Zea mays L.) cultivars, ‘LY336’ (shade tolerant) and ‘LC803’ (shade sensitive), to shade stress in a pot experiment conducted in the 2015 and 2016 growing seasons were investigated. The impact of 50% shade stress treatment on shoot biomass, photosynthetic parameters, chlorophyll fluorescence, and malondialdehyde (MDA) content was evaluated. The shoot biomass of the two maize hybrids was decreased significantly by shade stress treatment, for shade stress 7 d, the LC803 and LY336 were reduced by 56.7% and 44.4% compared with natural light. Chlorophyll fluorescence parameters of LY336 were not significantly affected by shade stress, whereas those of LC803 were significantly affected, the Fo increased under shade stress; however Fm, FV/FM and ΦPSII were decreased under shade stress. Among photosynthetic parameters measured, net photosynthetic rate (Pn), stomatal conductance (Gs), and transpiration rate were significantly decreased compared with natural light, LY336 and LC803 reduction by 28.0%, 22.2%, 57.7% and 35.5%, 18.9%, 62.4%; however, intercellular CO2 concentration (Ci) was significantly increased, for the two cultivars. Under shade stress for different durations (1, 3, 5, 7 d), Pn, Gs, Ci, and MDA content differed significantly between the two cultivars. Results indicated that different maize genotypes showed different responses to shading. Shade-tolerant genotypes are only weakly affected by shade stress.

花期高温不仅使玉米减产,而且降低籽粒品质,给玉米生产带来重大影响.综述了花期高温对玉米生理生化特性、穗发育、产量、籽粒品质的影响,并阐述了花期高温胁迫下玉米耐热相关基因研究进展,为玉米耐高温研究提供理论依据.

以35个玉米品种为材料,花期利用遮光度为50％遮阳网人工模拟寡照环境,测量雌雄间隔期、株高、穗位高、雄穗分枝数、雄穗长度、产量等14个性状,运用相关性分析、主成分分析、聚类分析、回归分析等多元统计分析方法对玉米品种进行耐荫性评价,筛选出玉米品种耐荫性评价关键指标,根据鉴定指标对玉米品种进行耐荫性划分.利用主成分分析和逐步回归优化出产量、行粒数、雌雄间隔期、穗粗4个耐荫性评价指标,以产量、行粒数、雌雄间隔期、穗粗4个性状平均隶属函数值进行聚类分析,将35个玉米品种分成耐荫性强、耐荫性弱两大类型.通过分析建立玉米品种花期耐荫性评价体系,产量、行粒数、雌雄间隔期、穗粗作为玉米品种花期耐荫性鉴定指标.

Limited adoption of advanced technologies and land fragmentation limit the sustainable intensification of agriculture in developing countries. Here, we explore and establish an integrated management strategy by combining the public-private partnership (PPP) and large-scale farming (LSF) for more profitable and sustainable no-tillage maize production. A case study was conducted in the North China Plain to determine the applicability and the key drivers underpinning PPP-LSF success. On average, maize under PPP-LSF yielded 10.4 Mg ha(-1), which was 11.8% and 19.4% greater than that of LSF and smallholder farming (SHF), respectively. Compared with LSF and SHF, the PPP-LSF achieved the highest energy use efficiency and the lowest negative environmental externalities. The carbon footprint of PPP-LSF was 267 kg CO2-eq Mg-1, which was 32.7% and 38.2% lower than that of LSF and SHF, respectively. A new causal factor analysis developed in this study revealed that the mechanised application of controlled-release formula fertilisers, eliminating top-dressing, was the main factor for low carbon footprint in PPP-LSF. The mean net ecosystem carbon budget (NECB), sustainability index, and net ecosystem economic benefit of PPP-LSF were 22.5 Mg C ha(-1), 17.1 and 2040 $ ha(-1), respectively, which were increased by 15.3% and 23.9%, 55.5% and 69.3%, and 28.7% and 50.3% compared with LSF and SHF. Higher net primary productivity related soil carbon sequestration potential and lower field carbon emissions were the main drivers of high NCEB of PPP-LSF. This real-world commercial crop production-based example illustrates the value and potential of PPP-LSF in utilising modern innovative farming technologies and management strategies to accelerate agricultural productivity and resources conservation with reduced environmental footprints.

为研究叶面喷施营养剂对玉米生长发育及产量的影响,以不喷施叶面肥为对照,设置3个试验组,在玉米的不同生长阶段喷施营养剂,研究营养剂中的微量元素对玉米生长发育造成的影响.结果表明,大喇叭口期喷施2种营养剂,对玉米发育进程、倒折率、空秆率、抗逆性状影响不明显;喷施"十二元素"可有效降低节间长度,提高抗倒伏能力;喷施营养剂能明显减小尖秃长度,粒重增加,出籽率升高.

本文作者系统介绍了漯河市农业科学院从1995-2015年间培育出的7个"漯"字牌系列芝麻新品种的选育、特征特性,以及配套的高产高效栽培技术和病虫草害综合防治措施,以期为漯芝系列品种在不同芝麻主产区的大面积推广种植提供技术支撑,为农民增收、农业增效提供帮助.

Climate change can have significant impacts on maize (Zea mays L.) grain yield. In this study, we used extensive multi-year field experimental data (n = 423) across different climatic regions of China to distinguish effects of different climate factors on maize grain yield and mimicking the effect of climate change, in particular, temperature and solar radiation. Across the years and climatic regions, the major driver for the yield difference was found to be the diurnal temperature range (DTR) and accumulated photosynthetically active radiation (PAR). 1 degrees C decrease in DTR and 100 MJ decrease in accumulated PAR resulted in 1.0 t ha(-1) and 0.85 t ha(-1) reduction in maize grain yield, respectively. 1 degrees C increase in growing season mean temperature (Tmean) and minimum temperature (Tmin) resulted in 0.83 t ha(-1) and 0.67 t ha(-1) maize grain yield reduction. By mimicking the effect of climate change on maize grain yield, it was found that 1 degrees C increase in Tmean resulted in 0.83 t ha(-1) (5.8%) maize grain yield reduction. Decrease in PAR also decreased maize grain yield significantly and the 1% decrease in PAR decreased maize grain yield by 0.15 tons per ha. Among all the five cultivars in this study, yield reductions of ZD958 and NH101 induced by 1 degrees C increase in Tmean were the smallest compared to other three cultivars. The quantitative analysis can provide important guidance to predict possible quantitative outcomes of future changes in crop productivity due to climate change and search for effective mitigation strategies such as cultivar selection.

以漯玉16等10个夏玉米杂交组合为材料,分析其生育期、抗倒指标(茎腐病发生率、茎秆抗倒折强度和穗位比),研究成熟后延期10 d收获的籽粒指标(含水量、完好籽粒率和理论产量)及完好籽粒产量,旨在为筛选适合豫中南延期机械粒收的夏玉米杂交组合提供理论依据.结果表明,漯玉184、漯玉16、漯玉197、漯玉19和漯玉18的生育期比对照(郑单958)短且生育期<107 d;漯玉16、漯玉197和漯玉184的茎秆抗倒折强度分别比对照高10.51％、8.92％、3.97％;漯玉197、漯玉16、漯玉184、漯玉186的穗位比分别比对照显著低12.68％、12.36％、11.82％、9.94％;漯玉184、漯玉16、漯玉197、漯玉183、漯玉19和漯玉18收获时的籽粒含水量分别比对照低18.31％、14.44％、5.99％、5.63％、3.17％和1.76％,差异显著且含水量<28％;漯玉16、漯玉197、漯玉184和漯玉18的完好籽粒率分别比对照高4.28％、3.73％、2.74％和1.75％,差异显著且完好率≥92％;漯玉16、漯玉197、漯玉19、漯玉18、漯玉186和漯玉184的完好籽粒产量分别比对照显著高6.92％、5.78％、3.69％、3.52％、3.06％和1.72％;成熟后延期10 d收获条件下,由生育期、抗倒指标和籽粒指标构成的隶属函数值表现为:漯玉16>漯玉197>漯玉184>漯玉19>漯玉18>漯玉186>郑单958>漯玉181>漯玉183>漯玉182.综上,在豫中南光热条件下,漯玉16和漯玉197的生育期、抗倒指标、延期10 d收获的籽粒指标和完好籽粒产量均达到机械粒收标准,可以延期机械粒收;漯玉184的理论产量偏低,但其完好籽粒产量较高,也可以进行延期机械粒收.

以玉米杂交种郑单958、漯玉16和先玉335为试验材料,分别在6月1日、6月8日、6月15日和6月22日播种,考查品种在不同播期下播种至出苗、播种至拔节、播种至抽雄、播种至吐丝及播种至成熟的天数和产量指标,研究豫中南夏玉米品种在不同播期下的生育进程及产量变化规律.结果表明,不同播期下3个品种播种至出苗及播种至拔节的天数基本没有变化;播种至抽雄和播种至吐丝的间隔天数随着播期的推迟逐渐变短且趋势一致,播种至成熟的间隔天数也逐渐缩短;3个品种均呈现播种越早产量越高、播种越晚产量越低的趋势,且同一品种在不同播期间产量差异均极显著.

本文作者介绍了国品鉴芝麻新品种漯芝21号的选育过程和特征特性,详细阐述了芝麻茎点枯病、枯萎病、叶斑病、病毒病等常见病害的症状和防治技术,总结了芝麻蚜虫、芝麻天蛾、芝麻螟及地老虎、金针虫、蝼蛄等常见害虫的活动规律和综合防治措施,总结了芝麻田杂草类型、除草技术和注意事项等,以期为该品种的种植和推广提供参考.

以漯玉16等11个玉米杂交种为研究材料,在拔节至大喇叭口期通过智能温室模拟高温环境进行处理,对穗长、穗粗、子粒体积指标(粒长、粒宽和粒厚)、穗粒体积指标(穗周粒宽和有效穗长)和穗粒重进行分析,综合评价夏玉米拔节至大喇叭口期的耐高温能力.结果表明,拔节至大喇叭口期高温胁迫导致夏玉米的雌穗发育受阻,穗长变短、穗粗变细,子粒长度变短,有效穗长度和穗周粒宽度变小,穗粒体积变小,穗粒重下降.综合子粒体积指标(穗长和穗粗)和穗粒体积指标(穗周粒宽和有效穗长)的耐高温系数构成的隶属函数值,试验品种拔节至大喇叭口期的耐高温能力由强到弱依次为漯玉16、漯玉197、绿源9号、郑单958、漯玉172、漯玉18、漯玉19、漯玉186、先玉335、漯玉171、漯玉182.

Increasing crop yields while reducing environmental impacts are a great challenge to ensuring food security and environmental quality for the world agriculture. Increasing planting density appropriately is one of the most effective strategies for increasing maize (Zea mays L.) yield. In China, overuse of nitrogen (N) fertilization on maize has resulted in excessive N surplus in the soil and environmental impacts. To address this challenge we conducted 212 site-year field experiments at two planting densities of 60000 and 75000 plants per ha with the same inputs of N. Results showed that maize yield could be increased 5.59% across China and 10.5%, 2.7%, 5.2% and 10.3% respectively in Southwest (SW), Huanghuaihai (HM), North (NM) and Northwest (NW) maize regions without extra inputs of N. The Life-cycle assessment showed that reactive N loss intensity and GHG intensity decreased by 2.2% to 10.2% across different regions of China, indicating that yield increase could be achieved without extra N inputs and further negative environmental impacts if planting density was increased by 15000 plants per ha under the current condition of excessive N surplus in China. If farmers in China increase maize planting density by 15000 per ha across the whole country the total maize production from the same planting area of 2017 would be 290 Mt which will be close to the expected demand of 315 Mt by 2030 while reducing the environmental impacts of intensive agriculture.

为了筛选和分析耐高温逆境能力强的夏玉米品种,利用智能温室在玉米孕穗期模拟高温气象,研究分析孕穗期高温逆境对10个夏玉米杂交种的植株性状、穗部性状、花期、可育率和理论产量等指标的影响.结果 表明,高温逆境使孕穗期玉米的株高和穗位高变高,抽雄期、吐丝期和散粉期滞后,抽雄至散粉间隔期缩短,雌雄间隔期延长,穗长、穗粗、穗行数、行粒数、穗粒数、穗粒重、可育率和理论产量下降.通过对不同玉米品种在孕穗期高温逆境下的性状表现及其变化的差异分析和聚类分析,试验品种的耐高温热害能力由强到弱表现为:漯玉336＞漯玉16＞阳光98＞郑单958＞豫丰3358＞先玉335＞阳光99＞漯青19＞漯玉172＞漯玉171.

为了评价玉米杂交种的花期耐高温能力,利用智能温室模拟高温气象在玉米花期前后进处理,评价花期高温环境对阳光98等10个夏玉米杂交种的花期、植株性状与产量性状等指标的影响.结果表明,花期高温使玉米的株高、穗位高变高,抽雄期、吐丝期延后,雌雄间隔期变长,穗长、穗粗、穗粒数、穗粒重、成穗率、理论产量下降.综合不同玉米品种各性状的耐高温系数、高温处理的理论亩产和隶属函数值分析,漯玉336、阳光98、豫丰3358的花期耐高温能力强,郑单958、阳光99的花期耐高温能力较强,漯玉152、先玉335、漯玉151花期耐高温能力适中,漯玉164、漯玉167花期耐高温能力较弱.

在开花期采用人工模拟50％遮阴,研究了遮阴条件下16个玉米品种在遮阴条件下的差异.结果 表明:遮阴条件下穗长变短、穗粗变细、穗行数和行粒数减少、产量降低.以产量和行粒数的综合耐阴系数为指标对16个玉米品种进行耐阴性评价,分为耐阴性强和耐阴性弱2大类型,漯玉336、郑单958、登海605、阳光98、阳光99、先玉335、豫丰3358共7个玉米品种的耐阴性较强,而迪卡517、怀川39、金城12、北青340、迪卡653、豫禾588、泛玉98、晟玉21、创玉107共9个品种的耐阴性较弱.