河北省夏玉米品种基因型与环境互作综合分析

利用AMMI模型和GGE双标图,对2015年河北省夏播玉米区域试验中13个参试品种在10个试点的相关农艺性状进行分析,包括子粒产量、穗长和千粒重。结果表明,各农艺性状在不同基因型和环境间存在极显著差异,基因型和环境间存在极显著互作效应。参试品种丰产性表现较好的有龙华369、J1302、衡玉1182,丰产性表现较差的有澳玉698、JF33。衡玉1182、J1302、荃玉18、郑单958和龙华369品种稳定性表现较好,鑫研218稳定性最差。丰产性、稳产性和适应性较好的品种有J1302、衡玉1182和龙华369。     

GGE双标图模型在玉米新品种测试中的应用

利用GenStat软件对2017年春玉米区24个中熟新品种的多点测试进行分析,基于GGE双标图模型分析表明,各试验点中以吉林省公主岭柳阳鉴定点具有较强的品种区分能力,吉林省公主岭铁北区鉴定点最具有代表性,甘肃省武威靖远县不适合作为此试验的鉴定地。GGE双标图丰产性稳产型表明,吉单37表现最为突出。基于相邻标准法分析表明,农华218、吉单37表现最好。综合分析,GGE双标图在品种产量评价方面与相邻标准法结果基本一致,且GGE双标图可以更加全面有效地评估品种和试验地点。     

夏玉米主要农艺性状与产量之间的关系

本文利用相关和回归分析,研究了5个玉米品种主要农艺性状与产量之间的关系,结果表明,不同类型玉米品种的主要农艺性状与产量之间的相关差异较大。玉米单株穗长、穗行数、穗粒数、千粒重与产量之间的关系较为密切,其它性状与产量之间的关系因品种不同而异。农艺性状值的变化对产量影响很大。     

山东省不同年代玉米杂交种主要农艺性状演变规律的研究

通过对山东省70年代至90年代玉米杂交种主要农艺性状的分析,认为玉米杂交种产量的提高,主要是由于选育了紧凑型品种而增加了密度、公顷粒数和提高了子粒千粒重,其次是增加穗行数和穗粒数;山东省70年代至90年代玉米杂交种主要农艺性状的演变规律分为逐渐上升型(有产量、公顷株数、公顷穗数、公顷粒数和千粒重等性状)、逐渐下降型(小斑病病级)和平稳发展型(有株高、穗粒高、穗长、穗粒数、穗行数、大斑病和生育期等性状)三种类型。     

山区海拔与坡向对玉米产量性状的影响

对４个组合（品种）和４个海拔高度的阴阳坡玉米栽培研究表明：（１）海拔高度对玉米产量、穗行数、行粒数和千粒重的影响因组合（品种）不同而异;（２）阴坡和阳坡对玉米产量、穗行数、行粒数和千粒重的影响与海拔和玉米品种有关;（３）一般在山区适应性强、产量高的组合,千粒重有随海拔增加而增加的趋势,而且阴坡的产量、穗行数、行粒数和千粒重均高于阳坡。     

鄂西南特殊生态区玉米杂交种综合评价及主要农艺性状的关联度分析

利用灰色关联的分析方法,对恩施州2006年玉米区试A、B、C组参试的34个新组合及相应对照分组进行综合评价。结果表明:在鄂西南玉米种植区玉米杂交种产量与主要农艺性状的关联度大小排序为:生育期、穗长、抗倒性、株高、行粒数、穗位高、出籽率、千粒重、穗行数。与产量密切相关的性状是品种的生育期、穗长、抗倒性、株高、行粒数等。在选育玉米杂交种时,在保证适当的生育期和株高的前提下,要注重抗倒性、出籽率、长穗和多粒性状的选择,同时不要忽视千粒重和穗行数的选择。     

玉米产量与其它农艺性状的灰色关联度分析

应用灰色关联度分析方法，对玉米变量与其它农艺性状关系的密切程度进行了分析。结果表明，产量与９个性状的关联顺序依次为生育期〉千粒重〉穗长〉穗行数〉穗粒高〉出籽率〉株高〉行粒数〉秃尖。与产量关系密切的性状是生育期、千粒重、穗长、穗行数、穗位高和出籽率。     

夏玉米杂交种产量性状与产量的通径分析

选用30个玉米杂交种为供试材料,采用随机区组设计。经过对产量、穗长、行粒数、穗行数、千粒重等6个农艺性状进行相关分析和通径分析表明,对产量影响最大的因素是行粒数(r=0.5366),相关系数达显著水平。穗长(r=0.4989)、千粒重(r=0.4512)与产量的关系呈正相关。提高行粒数和千粒重,增加穗长并兼顾其他农艺性状是提高玉米产量的有效途径。     

夏玉米主要穗部性状结构分析和高产育种探索

利用17个玉米杂交种通过对7个穗部性状与产量进行相关和通径分析,结果表明:结实长、出籽率、穗长、行粒数、穗行数、千粒重与产量的相关系数均为正值且较大;出籽率、结实长、千粒重、穗粗、穗长对产量的直接通径系数也为正值且较大.因此,对产量影响较大的因素有出籽率、结实长和千粒重,提高出籽率和千粒重,增加结实长兼顾其它穗部性状是玉米高产的有效途径。     

不同年代主要玉米品种穗部性状演变研究

采用裂区试验设计,以密度为主区(15 000、45 000、75 000株/hm2),品种为副区,对我国不同年代34个主要玉米品种穗部性状演变进行了研究。结果表明:随着年代的更替,产量、穗长、穗粗、穗行数、行粒数、秃尖长、千粒重显著增加,出籽率显著降低。通径分析结果表明:主要穗部性状对产量的作用依次为穗粗千粒重行粒数出籽率,穗粗、千粒重、行粒数的增加是玉米产量提高的主要原因。在玉米品种选育中应保持行粒数,着重改良穗粗、千粒重,提高出籽率,并协调出籽率与其他性状的关系。     

玉米品种更替过程中品种群体整齐度的变化

选用1950~2010年具有代表性的11个品种,设置4个种植密度,测定株高、穗位高、果穗长、穗粗、穗行数、行粒数指标的整齐度。结果表明,随着品种的更替,株高、穗位高、穗长、穗粗、穗行数、行粒数的整齐度明显提高,株高整齐度的提升最为突出。随着种植密度的提高,玉米的群体整齐度下降,现代品种对增密响应更加明显;同等密度条件下,现代品种的群体整齐度均高于早期品种。相关分析表明,玉米产量与株高、穗位高、穗长、穗粗、穗行数、行粒数性状的整齐度具有明显正相关关系。玉米产量提升过程与品种的群体整齐度同步,株高、穗位高整齐度是最为直观的评价指标,通过品种改良和种植技术的改进提高群体的整齐度是进一步提升产量的技术途径之一。     

东北地区玉米氮高效品种筛选及产量组成因素分析

为了筛选适宜农民种植的高产、养分高效玉米品种,提高东北地区的氮肥利用率,在吉林梨树、辽宁铁岭和黑龙江哈尔滨设置高氮与低氮两个氮水平,各选择20个玉米品种,通过两年定位的田间试验,对其产量及其组成因素进行分析。结果表明,在吉林梨树县地区,良玉918和德美1号两年均表现为双高效品种,先玉335和迪锋128均表现为高氮高效型品种。在辽宁铁岭地区双高效品种有宏硕899、锦华299、沈玉21和迪卡159,先玉335表现为高氮高效品种。在黑龙江哈尔滨,京科728、天农9、誉成1、先玉335为双高效品种,高氮高效品种是德育919和益农玉10。与所有供试品种的平均值相比,两年3个地点平均,双高效品种在正常施氮、低氮条件下分别增产12.8%和16.2%。高氮高效型品种在正常施氮条件下的增产率为6.4%。两个氮水平下,双高效品种具有较多的穗数和穗粒数,高氮高效品种仅在高氮水平下具有较多的穗粒数,低氮高效品种仅在低氮水平下具有较高的穗粒数。     

辽南地区不同密度对12个玉米自交系农艺性状的影响

[目的]针对辽南地区12个玉米自交系不同种植栽培密度对其产量的影响进行研究。[方法]以适宜辽南地区的12份玉米自交系为材料,以自交系为主区,以3个种植密度5万、6.5万、8万株/hm2为副区进行裂区试验,对12个不同玉米自交系在3个不同密度下其主要农艺性状的差异性进行研究。[结果]不同玉米自交系在不同种植密度下产量等农艺性状表现不同,除穗行数无显著变化外,株高、茎粗、产量、穗长、穗粗5个农艺性状均表现显著负相关。自交系、密度互作影响也具有极显著差异。在供试12个玉米自交系中,丹299、中106、599-20、LNX-9不适宜作为选育密植型品种的亲本。[结论]为辽南地区密植型玉米品种的选育提供参考依据。     

豫麦54丰产性、稳产性、适应性及品质分析

为了全面解豫麦54的生产利用和育种价值,以1995-1998年河南省和黄淮南片小麦区域试验的结果为依据,通过产量、变异系数和回归系数对该品种和对照品种的丰产性、稳产性、适应性和品质进行分析比较。结果表明,豫麦54属于丰产、稳产型中筋品种,有较强的抗逆性与适应性,在产量结构三要素中,单位面积穗数对产量的贡献最大(0.5916),穗粒数次之(0.3606),千粒重最小(0.2634),增加穗数、提高穗粒数是其高产的关键。该品种产量主效应值大,品种×地点互作变异系数小,产量与环境的回归系数接近于1,在6 000-7 500 kg／hm2肥力水平下表现最好。     

Below-Ground Competition in a Maize/Groundnut Intercropping System as Affected by the Rooting Soil Layer

Abstract

A field experiment was conducted to compare the below-ground competition between the intercropped maize (Zea mays L.) and two groundnut (Arachis hypogea L.) cultivars regarding the rooting soil layer. Three rows of each cultivar of groundnut (cvs. X-14 and Red Spanish) were planted in between two rows of maize (cv. Badra) with inter-row spacing of 30 cm and intra-row spacing of 15 cm. Aluminium sheets, 10 cm in height, were placed as a root barrier between the maize and groundnut rows at three depths, i.e., 0-10 cm, 10-20 cm and 20-30 cm from the soil surface. In the control plot, the soil was trenched and refilled without the aluminium partitions. The ear and total biomass yield of the maize intercropped with X-14 with the root barrier at 0-10 cm depth, were significantly larger than those with the root barriers at the depths of 10-20 cm, 20-30 cm and the control. The yield (crop or total biomass) of the maize intercropped with Red Spanish was not significantly affected by the root barrier. In conclusion, groundnut cultivar X-14 was more suitable for intercropping with maize than Red Spanish, probably due to the differences in the rooting properties in the top soil layer.     

黄淮海不同夏玉米品种生长发育及产量对播期的响应

以黄淮海地区18个主栽品种为材料,进行3个播期处理,播期分别为6月3日、6月13日、6月23日,探讨黄淮海地区夏玉米生长发育和产量形成对播期的响应。结果表明,随着播期的推迟,夏玉米生育期缩短,株高、穗位高、穗三叶叶面积和单株干物重均呈降低趋势。不同玉米品种的百粒重和穗粒数随播期的推迟而降低,产量下降。不同播期条件下各种指标变动小的品种适应性强,适播期长,这些品种通过保持相对稳定的生育期、较大的光合叶面积,从而保证了较高的干物质积累,最终获得较稳定的产量。因此,适时早播有利于提高产量。在无法满足早播时,可以选择抗逆性强、适播期较长的联创825或产量优势强的迪卡653等品种,以避免高温或晚播造成的减产。     

滴灌量对新疆高产春玉米产量和水分利用效率的影响研究

通过设置不同灌溉量处理,研究新疆滴灌高产玉米(≥15 000 kg/hm2)的需水规律及其灌溉量对产量和水分利用效率(WUE)的影响。结果表明,两年两地(伊宁县、奇台)均表现为玉米产量随着灌水量增大而显著增加,灌水量显著影响穗粒重,而对收获穗数无显著影响;相同灌水量不同基因型间的耗水量无显著差异,但同一基因型不同灌水量处理间的耗水量均表现为随着灌水量增大而显著增大;同一灌水量不同基因型的水分利用效率有差异,不同基因型间均表现出较低灌量处理的水分利用效率较高。综合考虑产量和水分利用效率,现行高产田灌溉量减少10%或20%,可在不影响产量的同时达到节水的目的。     

Using pattern recognition for estimating cultivar coefficients of a crop simulation model

The introduction of a new cultivar in a process-based crop simulation model requires the estimation of cultivar coefficients that define its growth and development characteristics. An accurate estimation of these coefficients requires replicated field experiments that, in many cases, are not available to crop model users. The objective of this study was to employ a pattern recognition approach to estimate cultivar coefficients from a minimum set of experimental data for use with a crop simulation model. The pattern recognition approach is based on similarity measures. Its main goal is to classify groups of data or patterns based on either a priori knowledge or on statistical information extracted from the patterns. Based on the similarity measure as the central calculation of the pattern recognition approach, the algorithm searches the space of features of other cultivars in the database to find the most similar cultivar as the best match to the target cultivar. The approach of this study was based on a few key characteristics of maize crop growth and development, including anthesis and harvest maturity dates, maximum leaf area index (LAI_max), final above ground biomass, and grain yield, which were used as the features vector. To construct the feature database, 27,789 hypothetical cultivars were constructed by combining different values of the six cultivar coefficients of the Cropping System Model (CSM)-CERES-Maize. Experiments performed in Florida (FL) and Iowa (IA) USA, Spain, central Punjab, Pakistan, and in Piracicaba, SP, Brazil were selected and later modified to provide a full potential production environment. The crop model was run for potential production for all 27,789 hypothetical cultivars and the outputs of these simulations were used as the feature database. For evaluation of this approach, we used the features for 29 different maize cultivars as reported from field experiments that are available in DSSAT maize cultivar database and also for four additional cultivars of which two had not been used in any aspect of this study. The model was run for all 33 cultivars, using the best match cultivar coefficients, for the conditions of the three study sites and locations where the latter four cultivars have been grown. The simulated crop characteristics were compared with the same simulated crop characteristics based on the original coefficients used to run the simulation model. We found that the approach based on pattern recognition was able to estimate the cultivar coefficients with a reasonable accuracy. The coefficient of determination (r²), root mean square difference (RMSD), and relative root mean square of difference (RMSDr) confirmed that this approach provided reliable estimates for the maize cultivar coefficients. The highest R² (0.98) was obtained for anthesis in Florida and the lowest (0.57) was obtained for grain yield in Spain. The highest RMSD (8.8) was obtained for maturity in Spain, while the lowest RMSD (1.1) was obtained for aboveground biomass in Florida. Although the values for RMSD were different across the different sites, this approach provided a level of accuracy that might be acceptable, especially for users who only have one year of experimental data and demand the best possible initial guess for the coefficients of their specific cultivar. This approach has been implemented in a simple tool that can be easily applied by users of DSSAT and the CSM-CERES-Maize model.     

不同熟期玉米套作夏玉米可溶性糖含量与产量形成

试验以早、中、晚熟代表品种鲁原单14(LD14)、掖单22(YD22)和掖单13(YD13)为对象,两两相互套作,研究春夏玉米套种体系中夏玉米可溶性糖含量与产量形成的关系.研究结果表明,不同时期各器官的可溶性糖含量与经济产量之间有明显的相关关系.其中,全株可溶性糖含量在大口期、吐丝期与产量成显著负相关,乳熟期、成熟期则与产量成显著正相关:叶片中的可溶性糖含量,吐丝期与产量成正相关,乳熟期和成熟期成负相关;叶鞘与茎中的可溶性糖含量与产量的相关关系相同,均表现为:乳热期与产量成负相关,吐丝期与成熟期成正相关;