水稻耐储藏特性三年动态鉴定与QTL分析

doi:10.11983/CBB18188

植物学报 ›› 2019, Vol. 54 ›› Issue (4): 464-473.DOI: 10.11983/CBB18188

水稻耐储藏特性三年动态鉴定与QTL分析

刘进^1,²,姚晓云^1,²,余丽琴¹,李慧¹,周慧颖¹,王嘉宇^2,^*(),黎毛毛^1,^*()

1 江西省农业科学院水稻研究所/水稻国家工程实验室(南昌)/国家水稻改良中心南昌分中心, 南昌 330200
2 沈阳农业大学水稻研究所, 沈阳 110866

收稿日期:2018-09-03 接受日期:2019-02-11 出版日期:2019-07-10 发布日期:2020-01-08
通讯作者: 王嘉宇,黎毛毛
基金资助:
国家重点研发计划(2016YFD0100101-11);江西现代农业科研协同创新专项(JXXTCX201701-01);江西省青年科学基金(20171BAB214026)

Detection and Analysis of Dynamic Quantitative Trait Loci at Three Years for Seed Storability in Rice (Oryza sativa)

Jin Liu^1,²,Xiaoyun Yao^1,²,Liqin Yu¹,Hui Li¹,Huiying Zhou¹,Jiayu Wang^2,^*(),Maomao Li^1,^*()

1 Nanchang Sub-center, National Rice Improvement Center/National Engineering Laboratory for Rice (Nanchang)/Rice Research Institute, Jiangxi Academy of Agricultural Sciences, Nanchang 330200, China
2 Rice Research Institute, Shenyang Agricultural University, Shenyang 110866, china

Received:2018-09-03 Accepted:2019-02-11 Online:2019-07-10 Published:2020-01-08
Contact: Jiayu Wang,Maomao Li

摘要/Abstract

摘要：

种子耐储藏特性是粮食作物的特殊农艺性状之一, 耐储藏性能对种子生产和种质资源保存有重要意义。以粳型超级稻龙稻5 (LD5)和高产籼稻中优早8 (ZYZ8)杂交衍生的重组自交系(RILs)群体(共180个株系)为实验材料, 自然高温高湿条件下放置1年、2年和3年后, 对不同储藏时段种子发芽率进行比较, 并利用223个分子标记的遗传图谱进行动态QTL鉴定。结果表明, 不同储藏时段龙稻5的发芽率均显著低于中优早8, 株系间耐储性存在较大差异; 不同储藏时段发芽率显著相关, 相邻存储时段发芽率关系紧密。共检测到17个耐储性相关的QTLs, 3个老化时段分别检测到5、4和3个, 检测到5个动态条件QTLs, 单一QTL解释5.60%-32.76%的表型变异, 加性效应在-16.78%-16.95%范围内。主效QTL簇qSSC2、qSSC6、qSSC7和qSSC8能调控不同储藏时段的发芽率, qSSC6具有明显降低发芽率的效应。共检测到26对上位性互作位点, 主效QTL qSS1和qSS4参与上位性互作, 这表明上位性互作是调控耐储藏性状的重要遗传组成。研究结果为水稻(Oryza sativa)耐储性相关QTL的精细定位奠定基础, 同时丰富了耐储性分子标记辅助选择育种的基因资源。

关键词: 水稻, 自然老化, 种子耐储藏, QTL分析, 上位性互作

Abstract:

Seed storability is one of the most important special agronomic traits of grain crops, which has great significance for seed production and germplasm conservation. In this study, we obtained a set of recombinant inbred lines (RILs), containing 180 lines and 223 molecular markers for a genetic map, derived from the cross between Longdao5 (LD5) and Zhongyouzao8 (ZYZ8). The set was used to identify quantitative trait loci (QTL) for seed storability traits under natural aging (higher temperature and humidity) at 1, 2 and 3 years after rice harvest. Then the germination rates of seeds at different storage stages were compared and identified by dynamic QTLs. The germination rate of the parents (the germination rate of LD5 was significantly lower than ZYZ8 under different storage stages) and RILs population was significant different under different storage stages, with a significant correlation of germination rate under different storage stages. A total of 17 QTLs were detected to control seed storability; 5, 4 and 3 QTLs were detected for 3 natural aging stages; and 5 dynamic conditional QTLs were detected; these QTLs explained 5.60% to 32.76% of the phenotypic variation, with an additive effect of -16.78% to 16.95%. Among these QTLs, 4 major clusters qSSC2, qSSC6, qSSC7 and qSSC8 were stably and reliably detected under 3 environments; the remaining QTLs were expressed in a single environment. qSSC6 reduced the germination rate. We detected 26 pairs of epistatic interaction sites. The major QTLs qSS1 and qSS4 were also involved in the epistasis effect, so epistatic interaction was an important genetic component for seed storability. These results will provide information for genetic analysis and related QTL fine mapping and will also enrich the gene resources for molecular marker-assisted selection of seed storability.

Key words: rice, natural aging, seed storability, QTL analysis, epistasis interaction

刘进,姚晓云,余丽琴,李慧,周慧颖,王嘉宇,黎毛毛. 水稻耐储藏特性三年动态鉴定与QTL分析. 植物学报, 2019, 54(4): 464-473.

Jin Liu,Xiaoyun Yao,Liqin Yu,Hui Li,Huiying Zhou,Jiayu Wang,Maomao Li. Detection and Analysis of Dynamic Quantitative Trait Loci at Three Years for Seed Storability in Rice (Oryza sativa). Chinese Bulletin of Botany, 2019, 54(4): 464-473.

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链接本文: https://www.chinbullbotany.com/CN/10.11983/CBB18188

https://www.chinbullbotany.com/CN/Y2019/V54/I4/464

图/表 7

表1 2016-2018南昌市年温度与降雨情况

Table 1 Summary of temperature and rainfall conditions from 2016-2018 in Nanchang city

Years	Rainy days	Max temperature (°C)	Days of max temperature (>30°C)	Max mean temperature (°C)	Mean min temperature (°C)	Mean temperature (°C)
2016	192	38	101	22.68	16.10	19.39
2017	184	39	97	23.03	16.10	19.57
2018 (1-9 months)	130	38	119	25.34	17.71	21.53

图1 自然老化条件下不同存储时间水稻重组自交系(RILs)群体发芽率(GR)分布情况 (A)-(C) 分别表示自然老化(高温高湿)条件下存储1、2和3年后的发芽率; (D), (E) 分别表示1-2年和2-3年环境下发芽率动态变化值。亲本龙稻5 (LD5)和中优早8 (ZYZ8)发芽率分别采用实线和虚线箭头表示。

Figure 1 Distribution of germination rates (GR) under different seed dormancy time in the recombinant inbred lines (RILs) population of rice (A)-(C) GR of natural storage condition for 1, 2 and 3 years, respectively; (D), (E) Dynamic GR of natural storage condition for 1-2 and 2-3 years, respectively. GR of the parents (LD5 and ZYZ8) are indicated by black and dotted line arrows, respectively.

表2 不同存储年份水稻亲本和重组自交系(RILs)群体发芽率(GR)分布情况

Table 2 Distribution of germination rate (GR) after different aging treatments for parents and recombinant inbred lines (RILs) population of rice

Trait	Environment (Year)	Parents		RILs population
Trait	Environment (Year)	LD5	ZYZ8	Means±SD	Range	Skewness	Kurtosis
GR (%)	1	63.97±6.10	95.95±4.51**	56.34±26.89	0.00-100.00	-0.30	-0.88
	2	43.19±4.30	59.79±2.20**	32.92±29.32	0.00-96.55	0.49	-1.04
	3	0.00±0.00	56.12±2.05**	6.89±16.80	0.00-87.68	2.92	3.36
Dynamic GR	1-2	20.78±5.20	36.16±2.75**	23.42±29.59	-5.70-97.79	-0.03	0.01
	2-3	43.19±5.63	3.67±3.50**	26.02±28.28	-2.9-96.55	0.64	-0.45

表3 自然老化条件下不同存储时间水稻发芽率(GR)性状间的相关系数

Table 3 Correlation coefficients among germination rates (GR) of rice under different natural storage conditions

Traits	Environment (Year)	1	2	3
GR	1	1.000
	2	0.448**	1.000
	3	0.166*	0.347**	1.000

图2 自然存储条件下水稻种子耐储藏性状QTL在重组自交系(RILs)群体中的染色体分布

Figure 2 Location of QTLs detected for seed storability under natural storage conditions in rice on the genetic map of recom- binant inbred lines (RILs)

表4 自然存储条件下水稻种子耐储藏性状QTL定位

Table 4 Putative QTL for seed storability were detected under natural storage conditions in rice

Trait	Locus	Position	Marker	LOD value	PVE (%)	Additive effect
1 year	qSS3	75.5	RM6676-STS3.8	2.53	10.58	-8.77
	qSS4	26.1	R4M17-RM5688	2.85	14.49	10.27
	qSS6a	121.4	RM5814-RM412	5.28	13.53	-10.27
	qSS7a	96.2	RM8261-RM1209	2.85	7.29	-7.27
	qSS8a	85.5	R8M33-RM6976	2.79	6.88	-7.04
2 years	qSS2a	40.5	RM5897-RM5699	3.86	10.47	9.69
	qSS6b	107.4	RM6395-RM5814	2.88	11.27	-10.19
	qSS7b	108.2	RM3555-RM1306	2.71	5.78	-7.03
	qSS8b	89.5	R8M33-RM6976	3.79	12.12	-10.18
3 years	qSS1	102.5	R1M30-RM3240	3.13	9.20	5.78
	qSS2b	50.5	RM5699-RM300	3.01	6.46	4.29
	qSS7c	64.2	RM1135-RM11	3.21	10.05	5.32
1-2 years	qss2	41.5	RM5897-RM5699	2.98	10.13	-9.59
2-3 years	qss3	40.5	STS3.3-STS3.4	4.46	25.22	16.95
	qss6	107.4	RM6395-RM5814	6.52	32.76	-16.78
	qss8	91.5	R8M33-RM6976	2.54	5.60	-6.68
	qss12	86	STS12.2-RM1226	2.89	24.42	-14.64

图3 自然存储条件下水稻种子耐储藏性状QTL的上位性互作效应分析

Figure 3 QTL with epistasis effect estimate for seed storability in rice under natural storage conditions

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水稻耐储藏特性三年动态鉴定与QTL分析

Detection and Analysis of Dynamic Quantitative Trait Loci at Three Years for Seed Storability in Rice (Oryza sativa)

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