Crops ›› 2017, Vol. 33 ›› Issue (3): 13-18.doi: 10.16035/j.issn.1001-7283.2017.03.003

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Quantitative Genetic Research of Plant Height and Ear Height in Maize under Different Environments

He Wenzhao,Wang Hongwu,Hu Xiaojiao,Li Kun,Wang Qi,Wu Yujin,Liu Zhifang,Huang Changling   

  1. Institute of Crop Sciences,Chinese Academy of Agricultural Sciences,Beijing 100081,China
  • Received:2017-04-02 Revised:2017-05-04 Online:2017-06-15 Published:2018-08-26
  • Contact: Hongwu Wang,Changling Huang

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Abstract:

Using a recombinant inbred line (RIL) population derived from the cross between Zhongdan 909’s parental lines Zheng 58 and HD568, we studied the genetic characters of plant height and ear height of maize under different environments. Analysis of phenotype data from RIL population and their parents showed that plant height and ear height had high broad sense heritability, but still significantly affected by environment factors. The joint segregation analysis of the three generations revealed that the plant height fitted the genetic model of F-2 in environment Ⅰ (Xinxiang,Henan; Summer of 2015) and genetic model of G-0 in both environments Ⅱ (Xinxiang, Henan; Summer of 2016) and Ⅲ(Gongzhuling, Jilin; Spring of 2016); Ear height fitted the genetic model of F-2 in environments Ⅰ and Ⅱ, and genetic model G-0 in environment Ⅲ. The results indicated that environment factors had a significant effect on the genetic models of these two traits. Study of the genetic laws of plant height and ear height under different environments will provide a theoretical basis for QTL mapping and breeding maize varieties with wide adaptability.

Key words: Maize, Plant height, Ear height, Genetic model

Table 1

The phenotypic analysis of parents and RIL population in three environments m"

环境
Environment		 性状
Trait		 亲本 Parent RIL群体RIL population
郑58 Zheng 58 HD568 均值±标准误Mean±SE 峰度Kurtosis 偏度Skewness 变异系数CV (%)
Ⅰ 株高Plant height 1.54 1.82 1.69±0.01 -0.27 -0.07 11.93
穗位高Ear height 0.54 0.71 0.61±0.01 -0.06 0.27 18.75
Ⅱ 株高Plant height 1.54 1.76 1.65±0.01 -0.49 -0.30 11.61
穗位高Ear height 0.50 0.65 0.57±0.01 0.11 0.32 18.90
Ⅲ 株高Plant height 1.91 1.99 1.96±0.00 0.14 -0.08 11.14
穗位高Ear height 0.64 0.79 0.78±0.01 0.35 0.11 17.93

Table 2

The joint variance analysis of plant height and ear height of populations"

变异来源Source of variation 株高Plant height 穗位高Ear height
自由度DF 均方MS F值F value 自由度DF 均方MS F值F value
环境Environment 2 12.100330 2 123.96** 2 5.315545 2 057.54**
家系Genealogy 217 0.210972 37.03** 217 0.071884 27.82**
重复Repeat 1 0.002425 0.43 1 0.000103 0.04
环境×家系Environment×Genealogy 430 0.018232 3.20** 430 0.007909 3.06**
环境×重复Environment×Repeat 2 0.094939 16.66** 2 0.064114 24.82**
重复×家系Repeat×Genealogy 217 0.007113 1.25 217 0.002777 1.07
广义遗传力Generalized heritability (%) 91.35 88.99

Table 3

AIC of plant height in three environments"

模型代码
Model code		 环境Environment 模型代码
Model code		 环境Environment
Ⅰ Ⅱ Ⅲ Ⅰ Ⅱ Ⅲ
A-0 2 139.916 2 191.265 2 268.605 E-5 2 078.848 2 127.724 2 205.402
A-1 2 092.312 2 146.722 2 215.780 E-6 2 078.864 2 130.288 2 207.599
B-1 2 094.458 2 147.159 2 217.372 E-7 2 076.865 2 129.057 2 206.060
B-2 2 094.010 2 148.550 2 217.758 E-8 2 076.865 2 129.057 2 206.060
B-3 2 092.010 2 146.550 2 215.758 E-9 2 076.862 2 128.281 2 205.599
B-4 2 094.287 2 148.705 2 217.776 F-1 2 093.528 2 082.453 2 152.275
B-5 2 092.474 2 145.166 2 215.372 F-2 2 061.712 2 044.444 2 083.405
B-6 2 092.458 2 145.159 2 215.372 F-3 2 082.937 2 070.834 2 140.346
B-7 2 090.480 2 143.168 2 213.372 F-4 2 093.802 2 148.443 2 217.753
B-8 2 092.454 2 146.803 2 215.794 G-0 2 075.179 1 993.764 2 060.324
B-9 2 092.734 2 143.101 2 212.494 G-1 2 088.050 2 060.419 2 121.378
C-0 2 082.339 2 130.894 2 208.449 G-2 2 088.450 2 142.562 2 218.722
C-1 2 080.428 2 131.696 2 207.912 G-3 2 076.909 2 130.818 2 206.895
D-1 2 078.865 2 130.213 2 207.553 G-4 2 088.478 2 142.540 2 219.055
D-2 2 076.908 2 130.836 2 206.897 H-1 2 094.535 2 120.893 2 199.099
E-0 2 081.802 2 130.934 2 208.771 H-2 2 087.815 2 122.364 2 216.871
E-1 2 080.863 2 129.489 2 207.244 H-3 2 091.661 2 146.380 2 215.754
E-2 2 078.909 2 132.828 2 208.896 H-4 2 093.663 2 148.381 2 217.755
E-3 2 076.909 2 130.827 2 206.896 H-5 2 093.671 2 147.975 2 217.406
E-4 2 078.871 2 127.724 2 205.402

Table 4

The goodness of fit test of genetic model for plant height"

环境Environment 模型Mode 群体Population U12 U22 U32 nW2 Dn
Ⅰ F-2 P1 4.69(0.03) 2.45(0.12) 4.56(0.03) 0.54(<0.05) 0.93(<0.05)
P2 5.80(0.02) 2.50(0.11) 9.02(0.00) 0.65(<0.05) 0.99(<0.05)
RIL 0.61(0.44) 0(0.95) 7.56(0.01) 0.23(>0.05) 0.03(>0.05)
Ⅱ F-2 P1 3.34(0.07) 2.26(0.13) 1.13(0.29) 0.43(>0.05) 0.86(<0.05)
P2 2.22(0.14) 1.95(0.16) 0.03(0.86) 0.33(>0.05) 0.77(>0.05)
RIL 0.00(0.96) 0.25(0.62) 4.45(0.03) 0.13(>0.05) 0.02(>0.05)
G-0 P1 0(1) 0.05(0.82) 0.80(0.37) 0.07(>0.05) 0.36(>0.05)
P2 0(1) 0.01(0.93) 0.11(0.74) 0.05(>0.05) 0.32(>0.05)
RIL 0.25(0.62) 0.55(0.46) 1.06(0.30) 0.15(>0.05) 0.01(>0.05)
Ⅲ F-2 P1 0.69(0.41) 1.07(0.30) 0.85(0.36) 0.16(>0.05) 0.59(>0.05)
P2 3.40(0.07) 2.26(0.13) 1.28(0.26) 0.42(>0.05) 0.85(<0.05)
RIL 0.01(0.91) 0.26(0.61) 2.56(0.11) 0.09(>0.05) 0.00(>0.05)
G-0 P1 0(1) 0.07(0.79) 1.15(0.28) 0.07(>0.05) 0.37(>0.05)
P2 0(1) 0.00(0.98) 0.01(0.93) 0.05(>0.05) 0.30(>0.05)
RIL 0.04(0.84) 0.03(0.86) 0.01(0.94) 0.05(>0.05) 0.00(>0.05)

Table 5

AIC of ear height in three environments"

模型代码
Model code		 环境Environment 模型代码
Model code		 环境Envitonment
Ⅰ Ⅱ Ⅲ Ⅰ Ⅱ Ⅲ
A-0 1 835.468 1 847.213 1 966.698 E-5 1 774.078 1 784.986 1 903.061
A-1 1 779.063 1 790.235 1 915.104 E-6 1 774.553 1 786.200 1 903.223
B-1 1 782.112 1 792.191 1 915.481 E-7 1 773.314 1 784.586 1 900.961
B-2 1 780.514 1 791.819 1 916.873 E-8 1 773.313 1 784.586 1 900.961
B-3 1 778.514 1 789.826 1 914.873 E-9 1 772.491 1 784.196 1 903.130
B-4 1 780.927 1 792.179 1 917.103 F-1 1 788.007 1 792.090 1 902.219
B-5 1 780.248 1 790.235 1 913.482 F-2 1 765.586 1 758.921 1 893.372
B-6 1 780.112 1 790.191 1 913.481 F-3 1 776.683 1 781.170 1 895.952
B-7 1 778.301 1 788.251 1 911.482 F-4 1 780.204 1 791.580 1 916.759
B-8 1 779.104 1 790.381 1 915.393 G-0 1 783.438 1 779.353 1 861.105
B-9 1 779.223 1 789.122 1 915.449 G-1 1 781.481 1 795.126 1 902.249
C-0 1 773.737 1 785.009 1 904.627 G-2 1 789.977 1 798.374 1 933.262
C-1 1 774.246 1 784.195 1 911.481 G-3 1 774.866 1 785.317 1 912.535
D-1 1 774.419 1 786.163 1 905.648 G-4 1 789.971 1 798.344 1 933.257
D-2 1 774.870 1 785.318 1 912.546 H-1 1 790.813 1 791.743 1 911.049
E-0 1 778.026 1 788.785 1 907.467 H-2 1 777.609 1 778.617 1 918.277
E-1 1 776.058 1 786.927 1 905.223 H-3 1 778.046 1 789.455 1 914.709
E-2 1 776.868 1 787.317 1 914.542 H-4 1 780.047 1 791.455 1 916.711
E-3 1 774.868 1 785.318 1 912.540 H-5 1 780.011 1 791.320 1 916.519
E-4 1 774.078 1 784.986 1 903.061

Table 6

The goodness of fit test of genetic model for ear height"

环境Environment 模型Mode 环境Population U12 U22 U32 nW2 Dn
Ⅰ F-2 P1 4.63(0.03) 2.44(0.12) 4.33(0.04) 0.54(<0.05) 0.92(<0.05)
P2 3.15(0.08) 2.12(0.15) 1.10(0.29) 0.36(>0.05) 0.78(>0.05)
RIL 0.13(0.72) 0(0.95) 1.25(0.26) 0.05(>0.05) 0(>0.05)
Ⅱ F-2 P1 3.73(0.05) 2.28(0.13) 2.08(0.15) 0.42(>0.05) 0.83(>0.05)
P2 4.13(0.04) 2.37(0.12) 2.95(0.09) 0.47(<0.05) 0.87(<0.05)
RIL 0.24(0.63) 0.03(0.86) 1.43(0.23) 0.15(>0.05) 0(>0.05)
Ⅲ F-2 P1 5.19(0.02) 2.48(0.12) 6.36(0.01) 0.59(<0.05) 0.95(<0.05)
P2 5.66(0.02) 2.50(0.11) 8.38(0.00) 0.63(<0.05) 0.98(<0.05)
RIL 0.50(0.48) 0.01(0.94) 6.06(0.01) 0.21(>0.05) 0(>0.05)
G-0 P1 0(1) 0.05(0.82) 0.80(0.37) 0.07(>0.05) 0.36(>0.05)
P2 0(1) 0.01(0.93) 0.11(0.74) 0.05(>0.05) 0.32(>0.05)
RIL 0.07(0.79) 0.10(0.75) 0.05(0.82) 0.04(>0.05) 0(>0.05)

Table 7

The estimates of genetic parameters of the plant height"

一阶参数
1st order parameter		 估计值Estimate 二阶参数
2nd order parameter		 估计值Estimate
Ⅰ Ⅱ Ⅲ Ⅰ Ⅱ Ⅲ
m 154.89 297.89 362.17 σ2p 661.85 845.25 1 152.12
da 18.21 -20.61 -24.48 σ2mg 410.08 487.98 688.39
db -19.28 -20.58 -24.45 σ2pg - 356.09 451.52
dc -19.28 -20.60 -24.48 σ2e 251.77 1.18 12.21
iab - -20.57 -24.44 h2mg(%) 61.96 57.73 59.75
iac - -20.58 -24.44 h2pg(%) - 42.13 39.19
ibc - -20.56 -24.43

Table 8

The estimates of genetic parameters of the ear height"

一阶参数
1st order parameter		 估计值Estimate 二阶参数
2nd order parameter		 估计值Estimate
Ⅰ Ⅱ Ⅲ Ⅰ Ⅱ Ⅲ
m 54.85 51.23 121.97 σ2p 163.14 171.72 300.10
da 7.32 6.95 -8.33 σ2mg 109.99 114.40 111.55
db -7.24 -7.45 -8.31 σ2pg - - 185.82
dc -7.24 -7.45 -8.32 σ2e 53.15 57.32 2.73
iab - - -8.30 h2mg(%) 67.42 66.62 37.17
iac - - -8.30 h2pg(%) - - 61.92
ibc - - -8.30
iabc - - -8.29
[1] Flintgarcia S A, Jampatong C, Darrah L L , et al. Quantitative trait locus analysis of stalk strength in four maize populations. Crop Science, 2003,43(1):13-22.
doi: 10.2135/cropsci2003.0013
[2] 丰光, 刘志芳, 李妍妍 , 等. 玉米茎秆耐穿刺强度的倒伏遗传研究. 作物学报, 2009,35(11):2133-2138.
doi: 10.3724/SP.J.1006.2009.02133
[3] 勾玲, 黄建军, 孙锐 , 等. 玉米不同耐密植品种茎秆穿刺强度的变化特征. 农业工程学报, 2010,26(11):156-162.
doi: 10.3969/j.issn.1002-6819.2010.11.028
[4] 李清超, 李永祥, 杨钊钊 , 等. 基于多重相关RIL群体的玉米株高和穗位高QTL定位. 作物学报, 2013,39(9):1521-1529.
doi: 10.3724/SP.J.1006.2013.01521
[5] 刘小刚, 马飞前, 王红武 , 等. 玉米茎秆穿刺强度遗传研究.作物杂志, 2014(4):27-31.
[6] 马飞前, 刘小刚, 王红武 , 等. 玉米茎秆纤维品质性状及其相关分析.作物杂志, 2014(4):44-48.
[7] Zhang Z M, Zhao M J, Ding H P , et al. Quantitative trait loci analysis of plant height and ear height in maize (Zea mays L.). Russian Journal of Genetics, 2006,42(3):306-310.
doi: 10.1134/S1022795406030112
[8] Mdela L, Cldejr S, Dav B , et al. Mapping QTL for grain yield and plant traits in a tropical maize population. Molecular Breeding, 2006,17(3):227-239.
doi: 10.1007/s11032-005-5679-4
[9] Bai W, Zhang H, Zhang Z , et al. The evidence for non-additive effect as the main genetic component of plant height and ear height in maize using introgression line populations. Plant Breeding, 2010,129(4):376-384.
[10] Salvi S, Corneti S, Bellotti M , et al. Genetic dissection of maize phenology using an intraspecific introgression library. BMC Plant Biology, 2011,11:4.
doi: 10.1186/1471-2229-11-4 pmid: 21211047
[11] 王铁固, 马娟, 张怀胜 , 等. 玉米穗位高的主基因+多基因的遗传模型分析. 贵州农业科学, 2012,40(4):10-13.
[12] 王铁固, 马娟, 张怀胜 , 等. 玉米株高主基因+多基因遗传模型分析. 玉米科学, 2012,20(4):45-49.
doi: 10.3969/j.issn.1005-0906.2012.04.010
[13] 高树仁, 刘文研, 张玉胡 . 玉米株高的遗传分析. 黑龙江八一农垦大学学报, 2010,22(6):1-3.
[14] Gai J Y, Wang J K . Identification and estimation of a QTL model and its effects. Theoretical and Applied Genetics, 1998,97(7):1162-1168.
doi: 10.1007/s001220051005
[15] 盖钧镒 . 植物数量性状遗传体系.北京: 科学出版社, 2003.
[16] 曹锡文, 刘兵, 章元明 . 植物数量性状分离分析Windows软件包SEA的研制. 南京农业大学学报, 2013,36(6):1-6.
doi: 10.7685/j.issn.1000-2030.2013.06.001
[17] 李洪戈, 余坤江, 郭婷婷 , 等. 甘蓝型油菜无花瓣性状的主基因+多基因遗传分析. 江苏农业学报, 2014,30(2):253-258.
[18] 王建康 . 基因定位与育种设计.北京: 科学出版社, 2014.
[19] 邱正高, 王贵学, 杨华 , 等. 航空诱变糯玉米突变体株高穗位高遗传模型. 西南大学学报(自然科学版), 2008,30(3):60-65.
[20] 李颖 . 高油玉米主要性状主基因+多基因遗传分析. 长春:吉林农业大学, 2011.
[21] 赵刚, 吴子恺, 王兵伟 . 微胚乳超高油玉米株高和穗位高的主基因+多基因遗传模型. 安徽农业科学, 2007,35(17):5096-5098.
doi: 10.3969/j.issn.0517-6611.2007.17.032
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