Crops ›› 2020, Vol. 36 ›› Issue (5): 71-79.doi: 10.16035/j.issn.1001-7283.2020.05.011

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Comprehensive Evaluation of Phenotype Genetic Diversity in Japonica Rice Germplasm Resources in Different Ecological Zones

Gong Yanlong(), Lei Yue, Yan Zhiqiang, Liu Xuewei, Zhang Dashuang, Wu Jianqiang, Zhu Susong()   

  1. Guizhou Rice Research Institute, Guiyang 550006, Guizhou, China
  • Received:2020-02-27 Revised:2020-06-16 Online:2020-10-15 Published:2020-10-12
  • Contact: Zhu Susong E-mail:gongyanlong1208@163.com;13984033281@139.com

Abstract:

In order to explore the genetic diversity of japonica rice germplasm resources, to provide information in selection of parental lines and cross combinations, and to improve the breeding efficiency in japonica rice, a total of 80 japonica rice germplasm resources, including domestic and foreign cultivars, were employed as study materials to survey eight major phenotypic traits through variation coefficient, genetic diversity index, cluster analysis, correlation analysis, principal component analysis, a two-dimensional analysis and stepwise regression analysis. The results showed: The coefficients of variation of eight phenotypic traits were 11.06%-36.97%, among which, the variation coefficient of 1000-grain weight was the smallest and the variation coefficient of the grain number per panicle was the largest. The genetic diversity indexes of eight phenotypic traits were 1.54-2.06, among which, the genetic diversity index of panicle number per plant was the highest, and the genetic diversity index of seed setting rate was the lowest. At the euclidean distance of 9.0, 80 samples could be divided into four categories, with significant differences in phenotypic traits. According to the results of principal component analysis and comprehensive evaluation of 80 japonica rice germplasm resources, Guizhou Bidaxiang No.6 for comprehensive traits ranked the first, at the same time filter to filled grain number, 1000-grain weight, plant height, panicle length and panicle number per plant, a total of five phenotypic traits could be used as the key indicators of japonica rice germplasm resources comprehensive evaluation. Based on the analysis of principal component and scatter plot, four excellent types of germplasm resources were obtained, which behaved dwarf, long spike, strong tillering ability and high seed setting. Combined with the scatter plot results, the Dafangwannuo was an overlapping germplasm in the scatter plot, which could be used as intermediate material for breeding. Thus, this work provided an evaluation equation valuable in japonica germplasm resources.

Key words: Japonica rice, Germplasm resource, Genetic diversity, Evaluation

Table 1

Names and sources of japonica rice resources for testing"

编号
Number
资源
Resource
选育年份
Breeding
year
来源
Source
抽穗期
(月/日)
Heading
(Month/day)
成熟期
(月/日)
Mature
(Month/day)
全生育
期(d)
Full growth stage
编号
Nunmber
资源
Resource
选育年份
Breeding year
来源
Source
抽穗期
(月/日)
Heading
(Month/day)
成熟期
(月/日)
Mature
(Month/day)
全生育
期(d)
Full growth stage
1 武育粳3号 1992 中国江苏武进 7/28 10/01 153 41 盐丰47 2001 中国辽宁盘锦 8/01 10/01 153
2 武运粳192 不详 中国江苏武进 7/25 9/25 145 42 辽星17 2007 中国辽宁沈阳 8/02 10/01 153
3 镇稻99 2001 中国江苏丘陵 8/10 10/09 161 43 大方大白糯 不详 中国贵州毕节 8/10 10/09 161
4 香粳111 1998 中国江苏里下河 8/09 10/09 161 44 毕粳1708 不详 中国贵州毕节 8/16 10/14 166
5 徐稻9号 2015 中国江苏徐淮 7/30 9/28 150 45 大方晚糯 不详 中国贵州毕节 8/09 10/07 159
6 连糯1号 2014 中国江苏淮北 7/30 9/28 150 46 大方五里香 不详 中国贵州毕节 8/15 10/14 166
7 扬粳687 2010 中国江苏里下河 7/30 10/03 155 47 毕大香6号 不详 中国贵州毕节 8/10 10/09 161
8 粳7623 2009 中国江苏南京 8/08 10/07 159 48 六粳2号 1996 中国贵州六盘水 8/09 10/09 161
9 镇稻10号 2007 中国江苏丘陵 8/09 10/07 159 49 毕粳40 2002 中国贵州毕节 8/12 10/11 163
10 早单八 1985 中国江苏太湖 8/04 10/01 153 50 毕稻988 不详 中国贵州毕节 8/16 10/15 167
11 连粳4号 2007 中国江苏连云港 8/10 10/11 163 51 毕稻05 不详 中国贵州毕节 8/04 10/03 155
12 武运粳21 2007 中国江苏武进 7/30 10/02 154 52 毕稻8号 不详 中国贵州毕节 8/10 10/09 159
13 秀水123 2011 中国浙江嘉兴 8/14 10/14 166 53 毕稻08 不详 中国贵州毕节 8/14 10/14 166
14 秀水620 1993 中国浙江嘉兴 8/11 10/10 162 54 毕稻126 不详 中国贵州毕节 8/15 10/14 166
15 秀水02 不详 中国浙江嘉兴 8/10 10/10 162 55 楚粳28 2007 中国云南楚雄 8/08 10/07 159
16 秀水42 2001 中国浙江嘉兴 8/09 10/10 162 56 云陆29 1999 中国云南昆明 8/01 10/01 153
17 丙03-33 2007 中国浙江嘉兴 8/09 10/10 162 57 银光 2001 中国云南昆明 8/01 10/01 153
18 秀水52 2001 中国浙江嘉兴 8/09 10/10 162 58 楚粳27 2005 中国云南楚雄 8/09 10/07 159
19 嘉花1号 2004 中国浙江嘉兴 8/10 10/10 162 59 凤稻12号 不详 中国云南大理 8/10 10/07 159
20 秀水209 2003 中国浙江嘉兴 8/09 10/10 162 60 楚品3 不详 中国云南楚雄 8/16 10/14 166
21 绍糯9714 2002 中国浙江绍兴 7/30 10/03 155 61 滇禾优34 2013 中国云南昆明 8/10 10/09 161
22 辐农709 不详 中国浙江平湖 8/12 10/14 166 62 靖粳优2号 2005 中国云南昆明 8/02 10/01 153
23 甬粳18 2000 中国浙江宁波 8/09 10/08 160 63 金粳818 2018 中国天津 8/14 10/14 166
24 甬粳29 不详 中国浙江宁波 8/12 10/14 166 64 津稻372 2014 中国天津 7/30 10/02 154
25 甬粳33 2010 中国浙江宁波 8/10 10/08 160 65 津原-2 不详 中国天津 8/06 10/05 157
26 龙稻18 2014 中国黑龙江哈尔滨 7/26 10/01 151 66 津早稻 不详 中国天津 8/04 10/05 157
27 五常黑米 不详 中国黑龙江五常 7/08 9/15 135 67 原旱稻3号 2012 中国河南原阳 8/01 10/01 153
28 龙稻16号 2013 中国黑龙江哈尔滨 8/15 10/14 166 68 郑旱6号 2005 中国河南郑州 8/02 10/01 153
29 龙香189 不详 中国黑龙江哈尔滨 8/15 10/14 166 69 郑旱2号 2003 中国河南郑州 8/09 10/08 160
30 龙香稻1号 不详 中国黑龙江哈尔滨 8/15 10/14 166 70 洛稻998 2006 中国河南洛阳 8/09 10/08 160
31 稻花香2号 2009 中国黑龙江五常 8/01 10/01 153 71 新稻18 2007 中国河南新乡 8/01 10/01 153
32 五常黑谷 不详 中国黑龙江五常 7/08 9/15 135 72 水晶2号 不详 中国上海闵行 8/14 10/14 166
33 五优稻3号 2005 中国黑龙江五常 7/08 9/20 140 73 申优1号 2002 中国上海 8/19 10/16 168
34 吉粳83 2002 中国吉林四平 8/09 10/07 159 74 临旱1号 2010 中国山东临沂 7/30 10/01 153
35 延粳23 2000 中国吉林延边 8/02 10/01 153 75 阳光600 2010 中国山东郯城 7/25 9/25 145
36 吉粳106 2006 中国吉林四平 8/01 10/01 153 76 皖垦糯 2010 中国安徽合肥 7/30 10/02 154
37 吉农大15 2018 中国吉林长春 8/06 10/05 157 77 秋田小町 不详 日本 7/16 9/20 140
38 延组培1号 2000 中国吉林延边 8/07 10/08 160 78 一目惚 不详 日本 8/02 10/01 153
39 通223 不详 中国吉林通化 8/08 10/08 160 79 关东194 不详 日本 7/28 10/02 154
40 丹旱稻53 2012 中国辽宁丹东 8/09 10/08 160 80 初星 不详 日本 8/01 10/01 153

Table 2

Genetic variation of eight phenotypic traits in japonica rice resources in different ecological zones"

表型性状Phenotypic trait 平均值
Mean
变异范围
Variation range
标准差
Standard deviation
方差
Variance
变异系数
Coefficient of variation (%)
单株有效穗数Panicles per plant 8.68 2.00~15.00 2.57 6.61 30.00
株高Plant height (cm) 83.10 55.00~114.20 9.93 98.61 11.95
穗长Panicle length (cm) 17.77 13.60~25.36 2.77 7.67 15.59
每穗实粒数Filled grains per panicle 125.65 33.90~365.30 43.77 1 915.81 34.83
每穗总粒数Grains per panicle 151.39 38.10~402.30 55.97 3 132.64 36.97
结实率Seed setting rate (%) 85.28 46.00~98.00 0.14 0.02 16.42
千粒重1000-grain weight (g) 27.21 19.02~37.17 3.01 9.06 11.06
着粒密度Grain density (No./10cm) 85.27 27.70~182.40 28.00 784.00 32.84

Table 3

Genetic diversity index and distribution traits of japonica rice resources in different ecological zones"

表型性状Phenotypic trait 遗传多样性指数Genetic diversity index 集中范围Concentration range 占比Proportion (%)
单株有效穗数Panicles per plant 2.06 8.68~11.25 60.00
株高Plant height (cm) 2.01 78.13~98.00 81.25
穗长Panicle length (cm) 1.94 16.39~20.54 75.00
每穗实粒数Filled grains per panicle 1.77 103.77~147.53 71.25
每穗总粒数Grains per panicle 1.87 123.41~207.36 80.00
结实率Seed setting rate (%) 1.54 92.28~99.28 75.00
千粒重1000-grain weight (g) 2.01 25.70~30.22 73.75
着粒密度Grain density (No./10cm) 2.02 71.27~99.28 57.50

Fig.1

Clustering diagram of japonica rice resources in different ecological zones"

Table 4

Mean values of eight phenotypic traits from japonica rice resources in different ecological zones"

表型性状
Phenotypic trait
类群Group
单株有效穗数Panicles per plant 8.88 8.00 6.71 3.00
株高Plant height (cm) 83.44 73.80 80.94 74.00
穗长Panicle length (cm) 17.56 13.75 20.48 25.36
每穗实粒数Filled grains per panicle 120.17 33.90 195.13 365.30
每穗总粒数Grains per panicle 142.54 38.10 258.59 402.30
结实率Seed setting rate (%) 86.00 89.00 76.00 91.00
千粒重1000-grain weight (g) 27.39 25.22 25.59 24.22
着粒密度Grain density (No./10cm) 81.69 27.70 130.30 158.60

Table 5

Correlation analysis of eight phenotypic traits of 80 japonica rice resources in different ecological zones"

表型性状
Phenotypic trait
单株有效穗数
Panicles
per plant
株高
Plant
height
穗长
Panicle
length
每穗实粒数
Filled grains
per panicle
每穗总粒数
Grains per
panicle
结实率
Seed setting
rate
千粒重
1000-grain
weight
株高Plant height -0.07
穗长Panicle length -0.29** 0.07
每穗实粒数Filled grains per panicle -0.48** -0.02 -0.48**
每穗总粒数Grains per panicle -0.37** 0.06 -0.42** -0.84**
结实率Seed setting rate -0.10 -0.17 -0.05 -0.09 -0.44**
千粒重1000-grain weight -0.03 0.12 -0.10 -0.08 -0.17 -0.20
着粒密度Grain density -0.23* 0.08 -0.04 -0.64** -0.87** -0.51** -0.15

Table 6

Power vector (PV), eigenvalue, contribution rate, and cumulative contribution rate of first five principle components based on eight phenotypic traits"

表型性状Phenotypic trait 主成分1 PV1 主成分2 PV 2 主成分3 PV 3 主成分4 PV 4 主成分5 PV 5
单株有效穗数Panicle number per plant -0.2891 -0.4271 0.0057 -0.1008 0.5033
株高Plant height 0.0393 -0.2491 0.7397 -0.3321 -0.4748
穗长Panicle length 0.2693 0.3554 0.1296 -0.6652 0.4379
每穗实粒数Filled grain number per panicle 0.4918 0.2995 0.0502 0.1250 0.0082
每穗总粒数Grain number per panicle 0.5581 -0.0812 0.0262 0.0577 0.1409
结实率Seed setting rate -0.2188 0.6362 0.0204 0.1779 -0.2620
千粒重1000-grain weight -0.1320 0.1638 0.6572 0.5007 0.4753
着粒密度Grain density 0.4730 -0.3184 -0.0220 0.3685 -0.0746
特征值Eigenvalue 3.0956 1.5105 1.1124 0.9765 0.6705
贡献率Contribution rate (%) 38.6948 18.8812 13.9046 12.2058 8.3815
累计贡献率Cumulative contribution rate (%) 38.6948 57.5760 71.4806 83.6864 92.068

Fig.2

Scatter plot based on PCA in japonica rice resources PC represents the score values of principal components in different japonica rice resources, PC1, PC2, PC3 and PC4 represent the score values of the first, second, third and fourth principal component in different japonica rice resources, respectively"

Table 7

Comprehensive evaluation D value and ranking of 80 rice resources in different ecological zones"

排名
Ranking
D
D-value
编号
Number
排名
Ranking
D
D-value
编号
Number
排名
Ranking
D
D-value
编号
Number
排名
Ranking
D
D-value
编号
Number
1 1.1096 47 21 0.3336 18 41 -0.0419 4 61 -0.3429 68
2 0.9731 67 22 0.2963 62 42 -0.0514 3 62 -0.3434 41
3 0.9189 34 23 0.2788 52 43 -0.0515 21 63 -0.3709 40
4 0.8487 38 24 0.2345 35 44 -0.0580 9 64 -0.4325 2
5 0.7947 57 25 0.2227 24 45 -0.0806 26 65 -0.4342 12
6 0.7150 22 26 0.2186 8 46 -0.0816 20 66 -0.4449 75
7 0.7125 10 27 0.1904 73 47 -0.0968 61 67 -0.4659 44
8 0.6696 56 28 0.1817 55 48 -0.1086 15 68 -0.5279 13
9 0.6271 69 29 0.1700 60 49 -0.1233 78 69 -0.5321 46
10 0.5719 36 30 0.1368 37 50 -0.1484 16 70 -0.5641 74
11 0.5228 59 31 0.1205 70 51 -0.1564 6 71 -0.5694 71
12 0.5149 11 32 0.0888 54 52 -0.1643 23 72 -0.5799 5
13 0.4947 50 33 0.0709 1 53 -0.2109 76 73 -0.6383 65
14 0.4646 45 34 0.0414 49 54 -0.2299 79 74 -0.6525 77
15 0.4531 43 35 0.0018 58 55 -0.2308 72 75 -0.6680 64
16 0.4115 53 36 -0.0001 63 56 -0.2574 14 76 -0.7144 80
17 0.3816 19 37 -0.0037 51 57 -0.2654 29 77 -0.7164 7
18 0.3740 48 38 -0.0046 42 58 -0.2668 66 78 -0.7770 28
19 0.3699 25 39 -0.0092 33 59 -0.2890 17 79 -0.8368 27
20 0.3468 39 40 -0.0257 31 60 -0.3298 32 80 -0.9643 30

Table 8

Correlative coefficients between phenotypic traits and D-value in japonica rice resources in different ecological zones"

表型性状
Phenotypic trait
相关系数
Similarity coefficient
单株有效穗数Panicle number per plant -0.659**
株高Plant height -0.554**
穗长Panicle length -0.308**
每穗实粒数Filled grains number per panicle -0.184
每穗总粒数Grains number per panicle -0.194
结实率Seed setting rate -0.068
千粒重1000-grain weight -0.027
着粒密度Grain density -0.079
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