Evaluation of early-maturing European maize inbreds for resistance to the European corn borer

The European corn borer (ECB) has become a serious pest for maize cultivation in Central and Western Europe. This study was conducted to evaluate resistance against ECB in a cross section of the European maize germplasm. A total of 115 flint and dent inbreds were evaluated for resistance under protected and artificial infestation conditions at two German sites in 1993. Resistance to ECB was assessed by damage rating before harvest, tunnel length in dissected stalks, and relative yield under infestation compared to protected control plots. Means for damage rating of stalks were significantly higher in flint lines than in dent lines. Artificial infestation reduced grain yield by 31% in flint lines and 20% in dent lines. Significant genotypic variances among lines and high genetic ratios (GR) were found in both flint and dent lines for all agronomic and ECB resistance traits. Exceptions were relative yield of stover in both germplasm groups and tunnel length in flint lines. Phenotypic correlations between agronomic and resistance traits were moderate to low. Damage rating was negatively correlated with days to silking and dry matter yield of stover in both germplasm groups. In vitro digestibility of stover was not associated with ECB resistance. Correlations of relative grain yield with tunnel length below the ear and damage rating were significantly negative, even though their magnitude was low. Our results indicate substantial genetic variation among European inbred lines for resistance to the univoltine ECB. Among all resistance traits measured, damage rating of stalks is best suited for assessment of ECB resistance in breeding programs because of its easy recording and high genetic ratio. This revised version was published online in July 2006 with corrections to the Cover Date.     

Genetic variation in testcrosses of European maize inbreds for resistance to the European corn borer and relations to line per se performance

The European com borer (ECB) Ostrinia nubilalis H. is a major pest in World maize Zea mays L. production. Objectives of this study were to (1) investigate the genotypic variance and covariance in testcrosses of European flint and dent inbreds for ECB resistance and agronomic traits, and (2) estimate the correlation between line per se and testcross performance for ECB resistance traits. A total of 16 flint and 24 dent inbreds and their testcrosses with two testers from the opposite germplasm pool were evaluated in four and three German environments, respectively. Using artificial infestation with ECB larvae, resistance was assessed by damage rating of stalks, tunnel length in dissected stalks, and relative yield of infested plots compared with protected plots. Yield losses due to ECB damage in testcross hybrids amounted to 40%. Significant genotypic variances between flint and dent lines and high heritabilities were found for damage rating of stalks for both line per se and testcross performance. Heritabilities were low or intermediate for tunnel length and relative grain yield. Correlations between line per se and testcross performance were tight for the damage rating of stalks and moderate for tunnel length and relative yield in both flint and dent germplasm. For damage rating of stalks, per se performance of lines tested in a few environments can be used to predict their testcross performance. In contrast, assessment of testcross performance for tunnel length and relative yield requires evaluating testcrosses with several testers in multi-environment trials.     

Resistance of early-maturing European maize germplasm to sugarcane mosaic virus (SCMV) and maize dwarf mosaic virus (MDMV)

Sugarcane mosaic virus (SCMV) and maize dwarf mosaic virus (MDMV) are the most important viruses of maize in Europe. In field and greenhouse experiments, 122 early-maturing European maize inbreds (45 flint and 77 dent lines) were evaluated for their reaction to artificial inoculation by SCMV and MDMV. Three dent inbreds (D21, D32, FAP1360 A) with complete resistance and four dent inbreds (D06, D09, R2306, FAP1396A) with partial resistance against both potyviruses under both greenhouse and field conditions were identified. All other inbreds were highly susceptible to both SCMV and MDMV. Selection for virus resistance in maize breeding could be performed with only one virus at a time because all inbreds resistant to SCMV were also resistant to MDMV. Rank correlations between percentages of infected plants in greenhouse and field trials ranged from 0.51 to 0.72 for both SCMV and MDMV, suggesting that prescreening of breeding materials for virus resistance can be performed in the greenhouse but final evaluation in multilocation trials in the field is recommended.     

Comparison of Bt maize hybrids with their non-transgenic counterparts and commercial varieties for resistance to European corn borer and for agronomic traits

The European corn borer (ECB), Ostrinia nubilalis (Hübner), is a major pest of maize (Zea mays L.) in Central Europe. In order to compare transgenic Bt maize hybrids with their non‐transgenic counterparts and commercial hybrids, field trials and a laboratory bioassay were conducted. The field experiments were performed at four locations with natural and manual infestation of ECB larvae in 1998 and 1999. Transgenic Bt hybrids showed significantly lower means than their corresponding non‐transgenic counterparts and commercial hybrids for all resistance traits (damage rating of stalks, number of larvae per plant, and percentage of damaged plants or ears under infestation). Bt hybrids containing the CryIA(b) gene under the control of green tissue and pollen‐specific promoters (event 176) showed a significantly higher percentage of damaged ears than Bt hybrids carrying the CryIA(b) gene under the control of a constitutive promoter (Mon810). Bt and non‐Bt hybrids showed no significant differences for all agronomic traits, except for plant height under insecticide protection and grain yield reduction under infestation, whereas Bt hybrids had significantly lower means than their non‐transgenic counterparts and other commercial hybrids. All resistance traits were significantly correlated with grain yield reduction. The laboratory bioassay confirmed the level of antibiosis of Bt hybrids against neonate ECB larvae. Bt hybrids showed the highest level of ECB resistance and therefore are an attractive method of preventing ECB damage within an integrated pest‐management system.     

Leafy reduced-stature maize for short-season environments: Yield and yield components of inbred lines

Development of maize (Zea mays L.) types that produce leaf area and mature quickly would increase production of maize in mid- to short-season areas. The leafy (Lfy1) and reduced-stature (rd1) traits both make contributions to this end. However, these two traits have not previously been combined. Our objective was to evaluate the yield and yield components of non-leafy normal-stature (NLNS), leafy reduced-stature (LRS), non-leafy reduced-stature (NLRS), and leafy normal-stature (LNS) maize inbred lines. The two genes, ‘Lfy1’ and ‘rd1’, were incorporated into a series of inbred lines resulting in a range of canopy architectures. Ten variables were recorded for each of 30 inbred lines over three years. The 10 variables were: corn heat unit requirement from planting to tasselling, corn heat unit requirement from planting to silking, days between tasselling and silking, grain moisture content, husk dry weight, cob dry weight, ear length, maximum ear circumference, grain yield and ratio of grain yield to moisture content. Reduced-stature inbred lines reached anthesis more quickly than normal-stature inbred lines. Grain moisture content was less in reduced-stature inbred lines than normal stature trait groups. Leafy-reduced stature plants had the highest ratio of grain to moisture content and the lowest grain moisture content at harvest. Inbred lines containing the rd1 trait matured more rapidly than other trait groups. The LRS trait group yielded more than the other groups, and showed great potential for use in mid- to short-season environments. This revised version was published online in July 2006 with corrections to the Cover Date.     

Relationship between European corn borer resistance and concentration of mycotoxins produced by Fusarium spp. in grains of transgenic Bt maize hybrids, their isogenic counterparts, and commercial varieties

The European corn borer (ECB), Ostrinia nubilalis Hb., is a major pest of maize in central Europe and promotes the infection of maize with Fusarium spp. In this study, transgenic Bt maize hybrids were compared with their isogenic counterparts, and with commercial hybrids from the recommended list with regard to their level of ECB resistance and their concentration of deoxynivalenol (DON), its 15‐acetyl (15‐A‐DON) and 3‐acetyl (3‐A‐DON) derivatives, nivalenol (NIV), fusarenon‐X (FUS‐X), fumonisins (FUM), and zearalenon (ZEN) in harvested grains. The field experiments were performed in Germany at four locations in 1999 and at five locations in 2000. Transgenic Bt hybrids showed significantly lower means than their corresponding isogenic counterparts and than commercial hybrids for all resistance traits: damage rating of stalks, number of larvae per plant, number of larvae per ear, and percentage of damaged plants or ears under infestation. Among all mycotoxins analysed, DON consistently showed the highest concentration across all year × location combinations. Mycotoxin concentrations varied significantly between locations, years and genotypes, whereas mycotoxin concentrations were not significantly different between infested and protected plots. Associations between ECB resistance traits and mycotoxin concentrations were not consistent across years. It is concluded that under central European conditions, the use of Bt maize hybrids will only slightly reduce the contamination of maize kernels with mycotoxins produced by Fusarium spp.     

Indirect response to selection for improving resistance to the Mediterranean corn borer (<Emphasis Type="Italic">Sesamia nonagrioides</Emphasis> Lef) in maize

Mediterranean corn borer (MCB) (Sesamia nonagrioides Lef) and European corn borer (ECB) (Ostrinia nubilalis Hbn) are the most important biotic stresses of maize in Europe. The first selection program to improve stalk resistance to MCB was carried out in the maize population EPS12. It has shown that selection was effective to improve stalk resistance to MCB and ECB, while yield was not significantly diminished. The objective of this research was to determine if correlated changes in EPS12 occurred due to selection for resistance to MCB. Cycles of selection per se and testcrosses to three testers were evaluated under MCB and ECB artificial infestation at two different Spanish locations during 2 years. Selection has significantly reduced cob damage, days to silking, plant and ear height, and 100-kernel weight; meanwhile early vigor was increased. These changes could rather be a consequence of unconscious selection and/or the genetic correlation of these traits with resistance than a consequence of genetic drift.     

遮阴对黄淮海玉米主栽品种农艺性状和产量的影响

为分析遮阴对黄淮海玉米主栽品种农艺性状、产量性状和产量的影响,以黄淮海种植面积最大的10个玉米品种为材料,种植在该地区4个省（市）,并设抽雄前遮阴7天和全生育期不遮阴2个处理。研究结果表明遮阴处理对黄淮海玉米主栽品种农艺性状、产量性状及产量均具有显著的影响,10个品种产量均显著的降低,6个品种抽雄吐丝间隔期延长,9个品种吐丝率下降;遮阴后产量降低与行粒数、穗长、穗粗、百粒重变小,秃尖变大有显著的相关性;‘伟科702’在10个品种中耐阴性最好,遮阴后4地点平均产量第一,吐丝率和产量降幅最低,其次为‘郑单958’、‘蠡玉16’和‘隆平206’。因此,生产上应选‘伟科702’等耐阴性较好的品种,耐阴育种方面应将行粒数、穗长、穗粗、百粒重、秃尖长度、吐丝率和抽雄吐丝间隔期等显著相关的性状作为耐阴性鉴定的指标。     

我国主要玉米自交系开花期耐旱性差异及改良

通过对37份我国主要玉米自交系两年的开花期耐旱性鉴定, 筛选出耐旱系12份(K22、 SH15、 X178、 P138、中自01、中自451、金黄96B、齐319、旱23、东91、临京11、 CA156). 在干旱胁迫下, 果穗吐丝延迟, 雌雄开花间隔增大, 结穗率下降, 籽粒产量严重降低; 雌雄开花间隔天数和结穗率与籽粒产量均呈极显著相关, 是可供耐旱性选择     

Hybrid breeding for fall armyworm resistance: Combining ability and hybrid prediction

Fall armyworm (FAW, Spodoptera frugiperda) emerged as a major lepidopteran pest destroying maize in sub-Saharan Africa. A diallel mating design was used to generate 210 experimental hybrids from 21 lines. Experimental hybrids and four checks were evaluated in two locations. Commercial checks suffered higher foliar and ear damage compared to the top 15 hybrids. Mean squares associated with the genotypic variation were higher than genotype-by-environment interactions for foliar and ear damage traits. Heritabilities were moderate to high. Significant correlations were observed between grain yield (GY) with ear rot (−0.54) and ear damage (−0.45). Positive and significant GCA effects were observed for GY in seven parental lines, which were developed from multiple insect resistance breeding programmes. CKSBL10153 has the highest GCA value for GY and shows significant GCA effects for foliar and ear damage traits. These lines were identified as the ideal combiners for GY and FAW resistance and are therefore recommended for utilization as testers in the development of FAW-resistant three-way cross-hybrid maize with correlated response for increased GY. GCA and marker-based prediction correlations of GY were 0.79 and 0.96, respectively. Both GCA effects and marker-based models were effective in predicting hybrid performance for FAW resistance.     

不同来源玉米自交系及杂交组合杂交当代子粒性状的差异分析

玉米杂种优势的研究对于提高玉米产量和品质有重要意义。对2013年海南三亚种植收获的89份温带自交系、59份热带/亚热带自交系和由这148份自交系随机组配的179份杂交组合进行当代子粒性状的测定。分析了温带玉米与热带/亚热带玉米自交系子粒性状的多样性与差异性,同时依据亲本来源的不同,探索了不同组合的杂交当代子粒性状的差异性。结果表明：温带来源的玉米自交系粒长和百粒重比热带/亚热带材料的粒长和百粒重显著偏长偏重;不同来源的自交系组配的杂交当代F₁,母本来源于温带的杂交当代F₁粒长显著长于母本来源于热带/亚热带材料;杂种优势分析结果说明,杂交当代F₁在粒厚和百粒重性状上表现的相对高亲和相对中亲优势强于粒长和粒宽。     

不同玉米杂交品种吐丝持续期特性及其对播期的响应

吐丝期是决定玉米产量的关键时期,研究其相关特性,对玉米生产意义重大。为准确分析不同玉米品种吐丝特性的差异及其对播期的响应,于2014年和2015年设置了3个玉米主推品种(郑单958、先玉335和京科968)的3个播期处理(早播:4月10日,中播:5月10日,晚播:6月10日),分析了各个处理间吐丝持续期的差异以及吐丝持续期与雌穗穗长变异及产量构成因素的关系。结果表明:(1)群体吐丝持续期在品种间存在显著差异,表现为先玉335 (9.12 d)郑单958 (8.94 d)京科968 (7.68 d)。随时间推进,玉米每天吐丝的比例与天数为先升高后降低的二次函数关系,每天最大吐丝比例为先玉335 (16.51%)郑单958 (17.07%)京科968 (19.98%)。京科968较郑单958和先玉335呈现吐丝集中,每天吐丝比例较高、吐丝持续期短的特点;(2)吐丝持续期在不同播期间差异显著,郑单958、先玉335和京科968不同播期间的吐丝持续期变幅分别为8.10～9.55 d、7.54～10.53 d和6.65～8.66 d,郑单958的吐丝持续期在不同播期间最稳定(CV=6.57%),其次为京科968 (CV=9.40%),先玉335的吐丝持续期在不同播期间的变化最不稳定(CV=11.68%);(3)吐丝持续期与雌穗穗长的变异系数呈显著正相关,与产量和穗粒数呈显著负相关,与千粒重不相关。播期对玉米吐丝持续期具有显著的调控作用。随吐丝持续期增加,玉米雌穗穗长的变异系数显著增大,群体果穗的整齐度降低,穗粒数显著减少,是玉米产量显著降低的主要原因。     

Genetic Diversity for RFLPs in European Maize Inbreds

Restriction fragment length polymorphisms (RFLPs) have been proposed for predicting the yield potential of different types of cross. Their has been evaluated in 15 flint and 12 dent inbreds from the European maize (Zea mays L.) germplasm as well as in 68 F₁ crosses (21 flint × flint, 14 dent × dent, and 33 flint × dent) produced between them. The materials were evaluated for F₁ performance and midparent heterosis of grain yield, dry matter content (DMC) and plant height in two environments in Germany. Genetic distances (GDs) between parental lines, calculated from RFLP data of 194 clone-enzyme combinations, showed greater means for flint × dent (0.67) than dent × dent (0.62) and flint × flint (0.55) crosses. Cluster analysis based on GDs resulted in a clear separation of flint and dent lines and agreed well with pedigree information. For the complete set of 64 crosses analyzed (excluding 4 crosses between closely related lines) correlations of GD with F₁ performance and heterosis were significant for all traits except F₁ performance of DMC. When separate calculations were performed for individual subjets of crosses, correlations of GD with Fl performance and heterosis were significantly positive (0.48 ≤ r ≤ 0.80) for all traits in the flint × flint crosses, but not significant for the subsets of flint × dent and dent × dent crosses. Our results confirm those of previous investigations in that the predictive value of RFLP data is restricted to crosses between lines from the same heterotic group, and cannot be applied to crosses between lines from genetically divergent heterotic groups.     

Selection efficiency of tunnel length and stalk breakage to obtain maize inbred lines resistant to stem borer attack

There is not any conclusive result about the most suitable trait for performing pedigree selection for improving maize performance against corn borer attack: tunnel length or stalk breakage. We have used simultaneously both selection traits in the same genetic backgrounds and the objective of the present work has been to compare the suitability of pedigree selection for tunnel length and stalk breakage in order to obtain inbred lines that per se and in hybrid combination show lower stem damage and good agronomic performance. Tunnel length is better as selection criteria for increasing resistance to corn borers, but, in some genetic backgrounds, genetic linkage between yield and stalk tunneling by stem borers could make that selection for reduced tunnel length resulted in significant yield reductions.     

Leafy reduced-stature maize for short-season environments: morphological aspects of inbred lines

Development of maize (Zea mays L.) types that produce leaf area rapidly and finish vegetative development quickly would increase production of maize in mid- to short-season areas. The Leafy (Lfy1) and reduced-stature (rd1) traits each make contributions to this end. However, these two traits have not previously been combined. Our objective was to evaluate the morphological aspects of non-leafy normal-stature (NLNS), leafy reduced-stature (LRS), non-leafy reduced-stature (NLRS), and leafy normal-stature (LNS) maize inbreds. Two traits, Lfy1 and rd1, were incorporated into a series of inbreds, resulting in a range of canopy architectures. Twelve variables were recorded for each of 30 inbreds over three years. The 12 variables were: seed emergence, above-ear leaf number, below-ear leaf number, dead leaf number at tasselling, live leaf number at tasselling, total leaf number, above-ear leaf area, ear leaf length, ear leaf width, ear height, internode length, and plant height. Inbreds containing the Lfy1 trait had more above-ear leaf area, above-ear leaf number, dead leaf number at tasselling, total leaf number and number of live leaves at tasselling than non-leafy inbred lines. Below-ear leaf number was not different among LRS, LNS, and NLNS inbred lines. LRS and NLRS inbred lines were also not different for below-ear leaf number. Plant height, ear height, and ear leaf length and width were higher in normal-stature than reduced-stature plants. The proportion of the seeds which emerged was higher for LRS inbreds than the other trait groups. This revised version was published online in July 2006 with corrections to the Cover Date.     

不同种质玉米自交系穗粒性状特征分析

玉米穗粒性状是决定产量的重要因素。为了明确不同种质玉米自交系的穗粒性状特征及对种质创新和高产育种提供参考,本研究以211个不同种质玉米自交系为材料,对穗长、穗粗、穗行数、行粒数、粒长、粒宽、粒厚、百粒重和籽粒密度9个穗粒性状进行统计和系统聚类分析。结果表明,供试玉米自交系间各穗粒性状均存在显著差异,除籽粒密度外均存在较大变异系数;采用欧氏距离法进行聚类分析将供试玉米自交系分为7个类群,穗长、穗粗、行粒数和粒长均以类群G6最高,粒宽和百粒重均以类群G5最高;郑单958和先玉335两大杂交种的4个亲本自交系各自所属类群相比,4个类群分别有单个或多个自交系多个性状较优,可以为育种工作中穗粒性状的改良提供依据。     

Increased resistance to <Emphasis Type="Italic">Ustilago zeae</Emphasis> and <Emphasis Type="Italic">Fusarium verticilliodes</Emphasis> in maize inbred lines bred for <Emphasis Type="Italic">Fusarium graminearum</Emphasis> resistance

Preliminary field observations in our maize breeding nurseries indicated that breeding for improved resistance to gibberella ear rot (Fusarium graminearum) in maize may indirectly select for resistance to another ear disease, common smut (Ustilago zeae). To investigate this, we compared the disease severity ratings obtained on 189 maize inbreds, eight of which included our inbreds developed with selection for gibberella ear rot resistance after field inoculation and breeding for 8–10 years. No correlation was found between disease severities for the 189 inbreds but the eight gibberella-resistant lines were consistently more resistant to smut. To further examine this relationship and to determine if these eight inbreds would be useful for developing inbreds with either common smut or fusarium ear rot (F. verticilliodes) resistance, we conducted a Griffing’s diallel analysis on six inbreds of maize, four with high levels of gibberella ear rot resistance representing all of the pedigree groups in our eight gibberella lines, and two with very low levels. Our most gibberella ear rot resistant inbreds, CO433 and CO441, had the lowest disease ratings for all three diseases, the consistently largest general combining ability effects and several significant specific combining ability effects. It was concluded that some inbreds bred specifically for gibberella ear rot would also be useful in breeding for resistance to common smut and fusarium ear rot.     

Development Traits Affecting Time to Low Ear Moisture in Maize

A diallel cross of six inbred lines of maize (Zea mays L.) from the Corn Belt of the USA and one inbred line (NZ1A) with characteristics of maize from the highlands of Mexico was grown in a cool, temperate environment. The objective was to investigate interrelationships and combining abilities of plant development traits likely to influence the time required to reach low ear moistures in the field. The traits were days to silking, days to physiological maturity, ear moisture at physiological maturity, grain filling duration and ear drying rate after physiological maturity. Grain yield and grain moisture at harvest were also considered. Differences among the hybrids of this diallel cross for ear and grain moisture at the usual harvest time were largely determined by differences in ear drying rate after physiological maturity, and not by differences in days to silking, days to physiological maturity, or in ear moisture at physiological maturity. General combining ability (GCA) effects were much larger than specific combining ability (SCA) effects for all traits. NZ1A had positive GCA effects for grain filling duration and negative GCA effects for ear moisture at physiological maturity which were outside the range of the Corn Belt lines suggesting that this line, or similar Mexican germplasm, could be useful for developing hybrids with high grain yields and low ear moistures at harvest in cool, temperate environments.     

Mapping of QTL for resistance to first and second generation of European corn borer using an integrated SNP and SSR linkage map

The European corn borer (ECB, Ostrinia nubilalis Hübner) is a major pest of maize (Zea mays L.) in North America and Europe. In this study, we mapped and characterized QTL affecting the resistance to the first (ECB1) and second generation (ECB2) of ECB and plant height with the aid of 164 SNP and 88 SSR markers. A total of 144 testcross (TC) progenies of double haploid (DH) lines developed from a cross of two parental lines from the Stiff Stalk germplasm pool were tested at six different locations in the USA under both natural and artificial infestation with ECB larvae. Resistance to ECB1 and ECB2 was assessed by measuring leaf feeding and stalk breakage, respectively, using a visual rating scale from 1 (severe damage) to 9 (no damage). Genotypic variance among the TC progenies was significant for all traits. Heritabilities were moderately high (0.69) for stalk breakage and plant height (0.75), but only moderate for leaf feeding (0.43). For stalk breakage, three QTL were detected that together explained 36% of the genetic variance, whereas for leaf feeding only one QTL was mapped, which explained 25% of the genotypic variance. For plant height, two QTL were identified, explaining 20% of the genotypic variance. The QTL for leaf feeding and stalk breakage mapped by us were located in chromosomal regions adjacent to those reported for other maize germplasm and therefore might be suitable candidates for marker-assisted selection (MAS) during line development.     

种植密度对贵州春玉米茎秆抗倒伏性能及籽粒产量的影响

为了明确密植条件下春玉米茎秆特性和产量的变化及其相互关系,为贵州春玉米密植高产提供理论依据和实践指导。以贵州广泛种植的玉米品种先玉1171和新中玉801为材料,设置3.0、4.5、6.0、7.5、9.0和10.5万株hm-26个密度,于2018—2019年开展田间试验,研究种植密度对春玉米茎秆形态特征和力学特性、空秆率、倒伏率和产量的影响。结果表明:(1)春玉米株高和穗位高随密度增加先增高后降低;增密后第3节长增幅最大,第3节单位茎长干重、穿刺强度和抗折力,第7节茎粗、干重和横截面积下降幅度最大;密度对茎秆横截面扁率影响不显著。品种之间比较,先玉1171节间长,第3、5节的节间干重和第3节穿刺强度显著高于新中玉801,第7节干重、节间粗、单位茎长干重、节间横截面积、横截面扁率和抗折力显著低于新中玉801。(2)倒伏率和空秆率随密度增加而增大,增密后先玉1171倒伏率显著高于新中玉801,空秆率显著低于新中玉801。(3)产量随密度增加先增加后降低,先玉1171和新中玉801分别在9.3万株hm^-2和8.6万株hm^-2时产量最高。增密后先玉1171比新中玉801增产10.28%,有效穗数和穗粒数更高。(4)相关和多元回归分析表明,株高、穗位高与倒伏率显著正相关,节间粗和单位茎长干物质对玉米茎秆抗折力的正向影响显著。产量与茎秆性状密切相关,株高对产量的正向影响最大。可见,不同春玉米茎秆抗倒伏性能和籽粒产量对密度的响应有差异,新中玉801增密后茎秆节间短而粗,单位茎长干重较大,抗倒伏能力较强。而先玉1171由于在高密度下空秆率比新中玉801低,有较高的有效穗数和穗粒数,因此高密度下产量更高。综合考虑茎秆性状和产量,先玉1171和新中玉801在贵州适宜密度分别为9.0万株hm^-2和8.5万株hm^-2。