张春宵^,1, 李淑芳^,1, 刘旭洋^,2, 刘杰¹, 刘文平¹, 刘学岩¹, 李春辉², 王天宇^,2, 李晓辉^,11吉林省农业科学院作物资源研究所,吉林公主岭 136100
²中国农业科学院作物科学研究所,北京 100081

Establishment of Evaluation System for Drought Tolerance at Maize Germination Stage Under Soil Stress

ZHANG ChunXiao^,1, LI ShuFang^,1, LIU XuYang^,2, LIU Jie¹, LIU WenPing¹, LIU XueYan¹, LI ChunHui², WANG TianYu^,2, LI XiaoHui^,11Crop Germplasm Resources Institute, Jilin Academy of Agricultural Sciences, Gongzhuling 136100, Jilin
²Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081

通讯作者: 王天宇,E-mail： wangtianyu@caas.cn; 李晓辉,E-mail： lixiaohui2002lix@163.com。

张春宵、李淑芳和刘旭洋为同等贡献作者。
责任编辑: 李莉
收稿日期:2019-11-3接受日期:2020-04-8网络出版日期:2020-10-01

基金资助:

农业农村部国家玉米良种重大科研联合攻关绿色品种鉴定评价.NB29-1 国家重点研发项目.2016YFD0100103

Received:2019-11-3Accepted:2020-04-8Online:2020-10-01
作者简介 About authors
张春宵,E-mail： chunxiao1000@126.com。

李淑芳,E-mail： xlsf@163.com。

刘旭洋,E-mail： 1021247118@qq.com。









摘要
【目的】中国玉米主产区多为干旱、半干旱地区,播种后遇旱问题时常发生,生产上实现良好的出苗与成苗率是保障玉米高产稳产的基础。鉴于不同的玉米品种对萌发期干旱胁迫反应不一,构建玉米萌发期耐旱评价技术体系,鉴定不同品种萌发期耐旱性,为玉米品种筛选与应用奠定基础。【方法】以从田间耕层采集的土壤为介质,设置从种子不能发芽到全部发芽的土壤含水量13个梯度,在25℃光照培养箱条件下测定5个代表性品种种子发芽率,建立不同土壤水分胁迫条件与发芽率的Logistic拟合方程,确立50%种子发芽率时土壤含水量（GW₅₀）;在此基础上,以5个品种GW₅₀平均值作为干旱处理强度,对32份品种的发芽率等11个性状进行测定,通过相关性分析、聚类分析和主成分分析等方法,解析种子发芽率与其他相关性状间的关系。【结果】在13个水分梯度下5个品种的发芽率拟合Logistic方程的决定系数R²为0.978—0.992,基于Logistic方程估算GW₅₀为18.2%—18.7%,GW₅₀平均值为18.5%。以18.5%土壤含水量作为干旱胁迫处理水平,对32份品种的发芽率等11个性状的分析结果显示,发芽率与胚芽鲜重、胚根鲜重、贮藏物质转运率具有显著的相关性,但相关系数均小于0.5,分别为0.36、0.40和0.38,而发芽率与胚根数等7个性状没有显著的相关性。聚类分析结果表明,基于发芽率以外10个性状的聚类分析将32个品种分为三类,分别包含13、10和9个品种,但这三类品种间的发芽率均值没有显著差异,说明这10个性状不能反映胁迫条件下的发芽率水平。对11个性状的主成分分析表明发芽率、胚芽干重和贮藏物质转运率在第一主成分具有较高的特征值,第一主成分对总方差的贡献率达到36.3%,这三个性状可以作为萌发期耐旱性评价的关键指标。基于建立的萌发期耐旱鉴定技术体系,所鉴定的32个品种中有4个属于萌发期耐旱型,22个属于为中间型,7个属于萌发期干旱敏感型。【结论】明确了限制种子发芽率50%的土壤干旱胁迫强度,提出种子发芽率、胚芽干重和贮藏物质转运率可作为萌发期耐旱鉴定的关键指标,构建了玉米萌发期耐旱鉴定技术方法体系。
关键词： 玉米;萌发期;土壤干旱;耐旱性;鉴评体系

Abstract
【Objective】The main maize-producing areas in China are mostly arid and semi-arid areas, in which drought often occurred after sowing. The sufficient germination rate is key precondition for maize production. However, the decreasing germination rate caused by drought threatens the production of maize. Thus, it is of great importance to discover the drought tolerant maize varieties at germination stage, which relies on the establishment of evaluation system for drought tolerant maize at germination stage. 【Method】In the present study, 13 soil water content treatments, which represented the maize germination rates from 0 to 100%, were set using field soil and the germination rates of five representative maize hybrids were analyzed. The 50% germination rate soil water content (GW₅₀) was determined based on the Logistic formula of germination rate and soil water content in five representative maize hybrids. Subsequently, 32 maize hybrids were treated with GW₅₀ as drought condition. The relationships between germination rates of 32 hybrids and other 10 traits were investigated using correlation, cluster and principal component analyses. 【Result】The fitting degree (R²) of Logistic regression between germination rate of five representative maize hybrids and thirteen soil water contents ranged from 0.978 to 0.992. The GW₅₀ of five representative hybrids, which were estimated by the Logistic regression formulas, ranged from 18.2%-18.7%, with mean of 18.5%. Under drought treatments of 18.5% soil water content, the germination rates of 32 hybrids showed significant correlation with germ fresh weight, radical fresh weight and storage material transport rate, but the correlation coefficients were all lower than 0.5, which was 0.36, 0.40 and 0.38, respectively. While the germination rates under GW₅₀ showed no significant correlation with other seven traits such as radicle number. Besides, cluster analysis based on 10 other traits divided 32 hybrids to three clusters, each containing thirteen, ten and nine hybrids, respectively. However, the mean germination rates of the three clusters showed no significant difference. PCA analysis revealed germination rate, germ dry weight and storage material transport rate had highest eigenvalue in first principal component, which could explain 36.3% of the total variance. These three traits could be considered as key targets for drought tolerance evaluation at germination stage. Using the soil drought method and key traits for evaluation of drought tolerance at germination stage, four, twenty-two and seven of the thirty-four hybrids were identified as drought tolerant, intermedium and drought susceptible types, respectively. 【Conclusion】In this study, soil drought treatment method of GW₅₀ was established for maize drought tolerance evaluation at germination stage. The germination rate, germ dry weight and storage material transport rate were identified as the key traits for high-throughput drought tolerance evaluation. Thus, an evaluation system for drought tolerance at maize germination stage was established.
Keywords：maize (Zea mays L.);germination stage;soil drought;drought tolerance;evaluation system


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本文引用格式
张春宵, 李淑芳, 刘旭洋, 刘杰, 刘文平, 刘学岩, 李春辉, 王天宇, 李晓辉. 土培条件下玉米萌发期耐旱鉴评技术体系研究[J]. 中国农业科学, 2020, 53(19): 3867-3877 doi:10.3864/j.issn.0578-1752.2020.19.002
ZHANG ChunXiao, LI ShuFang, LIU XuYang, LIU Jie, LIU WenPing, LIU XueYan, LI ChunHui, WANG TianYu, LI XiaoHui. Establishment of Evaluation System for Drought Tolerance at Maize Germination Stage Under Soil Stress[J]. Scientia Acricultura Sinica, 2020, 53(19): 3867-3877 doi:10.3864/j.issn.0578-1752.2020.19.002

0 引言

【研究意义】玉米是中国重要的粮食作物,在保障国家粮食安全方面具有举足轻重的作用^[1]。然而,中国玉米种植面积的三分之二分布在雨养农业地区,频发的干旱严重阻碍玉米生产的发展^[2],特别是在中国的北方春玉米区,播种期是干旱少雨的季节,时常受到春旱的威胁^[3],而且近年来机械单粒播种的快速推广应用,由萌发期干旱引起的缺苗断垄对玉米生产造成的损失表现尤为明显^[4]。因此,确立玉米萌发期耐旱鉴评的干旱处理方法和技术指标,科学鉴定评价玉米品种萌发期的耐旱性,对新品种鉴定、筛选与应用具有重要的实际意义。【前人研究进展】以往玉米耐旱研究多集中在大田干旱法、土壤盆栽法和PEG模拟干旱胁迫等方法。大田干旱法通过控制灌水量进行干旱处理,贴合生产实际中的干旱胁迫,多应用于苗后全生育期的耐旱鉴评^[5,6,7]。盆栽土壤干旱胁迫易于控制土壤水分,是玉米苗后借助设施耐旱研究中常用的干旱处理方法,适合玉米苗期耐旱鉴评^[8,9]。通过聚乙二醇（PEG）或甘露醇（mannitol）的水分胁迫处理是实验室常用的一种模拟干旱方式,然而这种方法会导致植物组织快速脱水,而且PEG、甘露醇本身会被植物吸收^[10]。针对玉米的不同生长发育时期耐旱性评价,研究者采用不同的性状指标。玉米的苗期耐旱性多以存活率、叶片相对含水量、叶绿素含量、光合速率等指标进行评价^[8-9,11]。在玉米的开花期及全生育期多以散粉-吐丝间隔、产量等为指标评价耐旱性^[5,6,7]。自HALL等^[12]在1983年首次提出干旱下玉米的散粉-吐丝间隔（anthesis-silking interval,ASI）与产量显著关联,ASI成为了评价玉米耐旱性的经典性状指标^{[13,14,15,16]}。【本研究切入点】纵观国内外玉米耐旱鉴定研究,萌发期耐旱性受到的关注较少,目前,少数报道采用PEG模拟干旱研究萌发期耐旱,所开展的PEG胁迫发芽率、发芽势等性状耐旱性评价^{[17,18,19,20,21,22]},虽然与耐旱性有密切的关系,但是与玉米实际生产中的大田土壤干旱还有差别^[10]。【拟解决的关键问题】本研究以耕层土壤为介质,设置13个土壤含水量梯度测定代表性玉米品种萌发期的发芽率,建立拟合Logistic模型估算50%种子萌发率时的土壤含水量（50% germination rate soil water content,GW₅₀）水平,确定进行玉米萌发期耐旱性鉴定适宜胁迫强度,并以GW₅₀为干旱处理强度,对32份玉米杂交种的发芽率等11个性状进行分析,进一步确定萌发期耐旱鉴定的关键指标,构建土培条件下玉米萌发期耐旱鉴定评价技术体系,从而为大规模的萌发期耐旱材料鉴定和后续研究奠定基础、提供方法参考。

1 材料与方法

1.1 试验材料

试验材料为32份商业化玉米品种（表1）,除吉单系列品种由吉林省农业科学院玉米研究所和吉农高新技术发展股份有限公司提供外,其余均从吉林省公主岭市种子市场购买。

Table 1
表1
表132份商业化玉米品种
Table 1The 32 commercial maize hybrids

序号 No.	品种名称 Hybrids		序号 No.	品种名称 Hybrids		序号 No.	品种名称 Hybrids
1	郑单958 Zhengdan 958		12	吉单50 Jidan 50		23	吉农大778 Jinongda 778
2	吉农大819 Jinongda 819		13	吉单66 Jidan 66		24	吉农玉719 Jinongyu 719
3	登海605 Denghai 605		14	吉单441 Jidan 441		25	金园15 Jinyuan 15
4	吉单551 Jidan 551		15	吉单505 Jidan 505		26	鹏玉1号 Pengyu 1
5	优迪919 Youdi 919		16	吉单511 Jidan 511		27	桥玉8号 Qiaoyu 8
6	先玉335 Xianyu 335		17	吉单513 Jidan 513		28	先达203 Xianda 203
7	迪卡517 Dika 517		18	吉单53 Jidan 53		29	翔玉218 Xiangyu 218
8	迪卡159 Dika 159		19	吉单558 Jidan 558		30	翔玉998 Xiangyu 998
9	富民108 Fumin 108		20	吉单56 Jidan 56		31	东农254 Dongnong 254
10	富民985 Fumin 985		21	吉单631 Jidan 631		32	源丰009 Yuanfeng 009
11	禾田4号 Hetian 4		22	吉单96 Jidan 96

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1.2 干旱处理方法

试验采用土壤干旱法,挖取吉林省农业科学院公主岭试验基地（124°48′34″E、43°30′23″N）0—20 cm耕层土壤,风干粉碎过筛,105℃烘干8 h,使其完全干燥,根据所需处理胁迫强度于土壤中加入定量水,充分混匀后放入塑料桶（内径16.5 cm、高20 cm）至14.5 cm。将玉米种子均匀播于2 cm深,覆盖3 cm干土,每个桶播种50粒种子,加盖阻止水分蒸发。放入培养箱中25℃避光萌发。

1.3 不同水分梯度下的发芽率拟合分析

以玉米品种郑单958、吉农大819、登海605、吉单551、优迪919为试验材料,设置15.0%、15.5%、16.0%、16.5%、17.0%、17.5%、18.0%、18.5%、19.0%、19.5%、20.0%、20.5%和21.0%共13个土壤含水量梯度（绝对土壤含水量,即加水重量/土壤干重×100%）。水分梯度处理方法与材料种植同上,每个处理50粒种子,采用完全随机设计,并且每2 d随机交换位置。处理第8天测定种子发芽率（germination rate,GR）,发芽的标准为萌发出的幼根达到粒长、幼芽达到粒长1/2^[23]。利用Curve Expert 1.4软件对各玉米品种在13个土壤含水量梯度及其获得的发芽率进行基于Logistic模型方程Y=A/(1+Be^-CX) ^[24]拟合,式中Y为发芽率,A为最大发芽率,X为土壤含水量,B和C为常数。根据模型估算GW₅₀。

1.4 GW₅₀胁迫强度下的表型鉴定

以GW₅₀为胁迫处理强度、土壤含水量22.0%为正常对照,每个处理设3次重复,每个重复50粒种子,采用完全随机设计,并且每2 d随机交换位置。对32份玉米品种在处理第8天测定发芽率、胚根长（radicle length,RL）、胚芽长（germ length,GL）、种子鲜重（seed fresh weight,SFW）、胚芽鲜重（germ fresh weight,GFW）、胚根鲜重（radical fresh weight,RFW）、种子干重（seed dry weight,SDW）、胚芽干重（germ dry weight,GDW）、胚根干重（radicle dry weight,RDW）、胚根数（radicle number,RN）和贮藏物质转运率（storage material transport rate,SMTR）。其中,发芽率的鉴定标准同上;使用游标卡尺测量胚根长和胚芽长;种子鲜重、胚芽鲜重、胚根鲜重在去土洗净擦干后使用天平测定;种子干重、胚芽干重、胚根干重在取样后105℃杀青20 min,80℃烘干至恒重,使用天平测定重量;人工调查胚根数;贮藏物质转运率=（芽干重+根干重）/（芽干重+根干重+种子干重）×100%^[25]。耐旱系数（drought tolerance coefficient,DTC）=（干旱处理性状值/正常对照性状值）×100% ^[26]。

1.5 表型数据统计分析

利用Excel 2010、SPSS 21.0和R 3.5.3软件,对32份玉米品种在GW₅₀和对照下的表型数据进行各性状相关性分析、聚类分析和主成分分析。采用Z-score标准化归一化方法,对干旱胁迫下的发芽率和贮藏物质转运率进行标准化处理,公式为Z_i=(X_i-X_mean)/X_std,其中Z_i为i样品归一化处理后的数据,X_i为i样品原始数据,X_mean为所有样品的性状的平均值,X_std为所有样品数据的标准差。

2 结果

2.1 5份玉米品种在不同土壤含水量梯度下的发芽率变化及GW₅₀的确定

以郑单958、吉农大819、登海605、吉单551、优迪919共5份品种为试验材料,在13个土壤含水量梯度下进行种子发芽率测定。结果表明,土壤含水量低于16.5%时,所有材料的发芽率为0;土壤含水量达到20.5%时,所有材料的发芽率为100%（图1）。对不同土壤含水量梯度与所测定的5份品种发芽率进行基于回归方程Logistic拟合,其拟合度（R²）变化区间为0.978—0.992,可以较好地模拟种子发芽率随土壤含水量的变化过程（图1和表2）。本试验条件下5份品种的GW₅₀值为18.2%—18.7%,平均为18.5%。

图1

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图1不同土壤含水量下种子发芽率拟合的Logistic回归曲线

Fig. 1The Logistic regression of maize seed germination rate under different soil water contents



Table 2
表2
表25份玉米品种在不同土壤含水量下的发芽率拟合Logistic方程
Table 2Logistic equations of germination rate and soil water contents in five maize hybrids

品种名称 Hybrids	回归方程 Logistic equations	拟合度 Fitting degree (R2)	50%种子萌发率时的土壤含水量 GW50 (%)
郑单958 Zhengdan 958	Y=103.048/(1+1.10×1015e-1.874X)	0.983	18.5
吉农大819 Jinongda 819	Y=107.042/(1+1.99×1012e-1.505X)	0.981	18.7
登海605 Denghai 605	Y=103.907/(1+1.04×1013e-1.642X)	0.978	18.2
吉单551 Jidan 551	Y=105.640/(1+4.28×1012e-1.554X)	0.992	18.7
优迪919 Youdi 919	Y=105.599/(1+1.11×1012e-1.485X)	0.985	18.6

GW₅₀: 50% germination rate soil water content
GW₅₀：50%种子萌发率时的土壤含水量

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2.2 GW₅₀胁迫强度下32份品种的萌发相关性状鉴定

以GW₅₀为旱胁迫强度,以土壤含水量22.0%为非胁迫对照,对32份品种的发芽率等11个性状进行测定和分析显示,在正常条件下,所有材料的发芽率≥96%（表3）。与对照相比,GW₅₀干旱胁迫下除种子鲜重、种子干重外其余性状均值都呈现降低,并且种子发芽率、胚芽鲜重、胚芽干重、胚芽长、胚根鲜重和贮藏物质转运率的表型变异系数均呈现增加,其中种子发芽率的变异系数增加幅度最大（表3）。基于胚芽鲜重、胚芽干重、胚芽长、胚根鲜重、胚根干重、胚根长、胚根数、贮藏物质转运率的耐旱系数平均值都小于100%,说明干旱胁迫下胚芽和胚根的生长、贮藏物质转运都受到了不同程度的抑制作用。其中,种子发芽率耐旱系数的平均值为60.17%;胚芽鲜重、胚芽干重和胚芽长这三个性状耐旱系数的平均值均小于30%,贮藏物质运转率耐旱系数的平均值为35.87%;而胚根鲜重、胚根干重、胚根长和胚根数耐旱系数平均值变化范围是39.46%—86.26%,表明萌发期干旱对胚芽的生长影响更大。

Table 3
表3
表3GW₅₀胁迫强度和非胁迫对照下32份品种的萌发相关性状变异分析
Table 3Trait variation of 32 hybrids under mean GW₅₀ and normal water treatment

处理 Treatments	性状 Traits	最小值 Minimum	最大值 Maximum	平均 Average	变异系数 CV
正常对照 Normal	种子发芽率GR (%)	96.00	100.00	99.44	1.28
	胚芽鲜重GFW (g)	0.20	0.60	0.40	26.09
	胚芽干重GDW (g)	0.02	0.06	0.04	27.55
	胚芽长GL (cm)	6.74	16.76	11.98	19.19
	胚根鲜重RFW (g)	0.09	0.42	0.24	40.80
	胚根干重RDW (g)	0.01	0.04	0.03	28.92
	胚根长RL (cm)	4.34	17.67	13.35	22.70
	胚根数RN	3.05	6.45	4.48	17.53
	种子鲜重SFW (g)	0.26	0.52	0.38	15.42
	种子干重SDW (g)	0.13	0.28	0.19	20.36
	贮藏物质转运率SMTR (%)	10.54	40.08	24.51	28.66
50%萌发率土壤含水量胁迫处理 GW50 treatment	种子发芽率GR (%)	19.00	92.00	59.88	26.75
	胚芽鲜重GFW (g)	0.03	0.16	0.08	38.70
	胚芽干重GDW (g)	0.00	0.03	0.01	44.61
	胚芽长GL (cm)	1.13	5.10	2.67	35.36
	胚根鲜重RFW (g)	0.03	0.17	0.09	38.22
	胚根干重RDW (g)	0.01	0.03	0.01	35.60
	胚根长RL (cm)	4.22	11.71	8.80	19.74
	胚根数RN	2.60	6.00	3.84	19.70
	种子鲜重SFW (g)	0.25	0.50	0.40	13.69
	种子干重SDW (g)	0.18	0.32	0.25	12.87
	贮藏物质转运率SMTR (%)	4.68	16.63	8.45	34.00
耐旱系数 DTC	种子发芽率GR (%)	19.79	92.00	60.17	26.60
	胚芽鲜重GFW (g)	7.59	44.62	20.13	38.43
	胚芽干重GDW (g)	13.91	86.85	29.18	48.08
	胚芽长GL (cm)	10.89	59.34	22.82	40.00
	胚根鲜重RFW (g)	21.17	84.64	39.46	34.75
	胚根干重RDW (g)	23.20	105.61	50.99	32.28
	胚根长RL (cm)	44.01	97.30	67.84	18.74
	胚根数RN	59.77	129.51	86.26	15.00
	种子鲜重SFW (g)	73.13	121.74	104.55	9.68
	种子干重SDW (g)	100.03	167.96	130.07	12.11
	贮藏物质转运率SMTR (%)	21.42	71.08	35.87	32.66

Mean GW₅₀: Mean 50% germination rate soil water content; DTC: Drought tolerance coefficient; GR: Germination rate; GFW: Germ fresh weight; GDW: Germ dry weight; GL: Germ length; RFW: Radical fresh weight; RDW: Radicle dry weight; RL: Radicle length; RN: Radicle number; SFW: Seed fresh weight; SDW: Seed dry weight; SMTR: Storage material transport rate. The same as below
Mean GW₅₀：平均50%萌发率土壤含水量;DTC：耐旱系数;GR：种子发芽率;GFW：胚芽鲜重;GDW：胚芽干重;GL：胚芽长;RFW：胚根鲜重;RDW：胚根干重;RL：胚根长;RN：胚根数;SFW：种子鲜重;SDW：种子干重;SMTR：贮藏物质转运率。下同

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2.3 GW₅₀胁迫强度下发芽率与其他性状的相关性分析

在GW₅₀胁迫强度下,发芽率与胚芽鲜重、胚根鲜重、贮藏物质转运率具有显著的相关性（P<0.05）,但相关系数（r）均小于0.5,分别为0.36、0.40和0.38（图2-A）。胚芽鲜重和胚芽长有显著（r=0.87,P<0.05）的相关性。此外,胚根鲜重、胚根干重和胚根数显著（P<0.05）正相关,但胚根长与胚根鲜重、胚根干重、胚根数均没有显著的相关性（P>0.05）。由于贮藏物质转运率是由胚芽干重、胚根干重和种子干重计算而来,这些性状间具有显著（P<0.05）的相关性。对以上性状的耐旱系数进行分析,发现发芽率耐旱系数与其他10个性状耐旱系数的相关系数也均小于0.5（图2-B）,表明在干旱下玉米种子的萌发能力和萌发后的生长能力是2种不同的抗旱性状。贮藏物质转运率与胚芽干重、胚根干重和种子干重间的耐旱系数具有显著的相关性（P<0.05）。

图2

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图2GW₅₀胁迫下发芽率与其他性状的相关性

A、B分别代表平均半萌发土壤含水量处理下表型的相关分析结果和性状耐旱系数的相关分析结果。GR：种子发芽率;GFW：胚芽鲜重;GDW：胚芽干重;GL：胚芽长;RFW：胚根鲜重;RDW：胚根干重;RL：胚根长;RN：胚根数;SFW：种子鲜重;SDW：种子干重;SMTR：贮藏物质转运率。下同
Fig. 2Correlation analysis of germination rate and other traits under mean GW₅₀

A and B represent the correlation analysis results of mean GW₅₀ treatment and drought tolerance index, respectively. GR: Germination rate; GFW: Germ fresh weight; GDW: Germ dry weight; GL: Germ length; RFW: Radical fresh weight; RDW: Radicle dry weight; RL: Radicle length; RN: Radicle number; SFW: Seed fresh weight; SDW: Seed dry weight; SMTR: Storage material transport rate. The same as below

2.4 GW₅₀胁迫强度下萌发相关性状的聚类分析

根据GW₅₀处理条件下除发芽率外其他10个性状的聚类分析结果,32个玉米品种可以分为3种类型,分别包含13、10和9个品种（图3-A）,以上3种类型品种在GW₅₀下的发芽率的平均值没有显著（P>0.05）差异（图3-B）。根据这10个性状耐旱系数的聚类分析结果,32个品种可以分为2种类型,分别包含19和13个品种（图3-C）,这2种类型品种在GW₅₀下的发芽率的平均值也没有显著（P>0.05）差异（图3-D）。结果表明,玉米在干旱胁迫下的萌发能力和萌发后的生长势是由不同的遗传和生理机制控制的,没有明显关联。

图3

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图3性状的聚类分析和聚类分组杂交种间的发芽率差异

A、B为GW₅₀下基于除发芽率外其他10个性状的聚类分析结果和不同分类材料的发芽率;C、D为基于这10个性状耐旱系数的聚类分析结果和不同分类材料的发芽率
Fig. 3Clustering analysis of traits and differences of germination rates between hybrids in different clusters

A and B represent the clustering results based on other 10 traits under mean GW₅₀ and germination rates of different cluster groups, respectively; C and D represent the clustering results based on the drought tolerance index of other 10 traits and germination rates of different cluster groups, respectively

2.5 GW₅₀胁迫强度下影响萌发期耐旱性性状的主成分分析

为了确定11个性状中的关键耐旱评价性状,对GW₅₀下的32个品种的11个性状进行主成分分析,结果表明第一主成分和第二主成分对总方差的贡献率分别为36.3%和19.1%（图4）,发芽率、胚芽干重和贮藏物质转运率对干旱处理下样品PCA分析的第一主成分具有较高的特征向量和特征值,表明这三个指标是玉米萌发期耐旱鉴定的关键指标。

图4

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图4GW₅₀胁迫下性状的主成分分析

Fig. 4Principal component analysis of traits under mean GW₅₀

2.6 对32份品种的萌发期耐旱性评价

对发芽率、胚芽干重和 贮藏物质转运率3个指标计算Z值（Z-score）进行归一化处理,以3个指标的平均Z值综合评价玉米品种的萌发期耐旱性（表4）。结果显示,以32个品种平均Z值的平均值±标准差为分界点,将全部品种分为萌发期耐旱型、中间型和干旱敏感型3种类型,其中吉单511、东农254等4个品种属于萌发期耐旱型,郑单958、先玉335等22个品种属于中间型,吉单53、吉单631等7个品种属于萌发期干旱敏感型。

Table 4
表4
表432份玉米品种发芽率、胚芽干重和贮藏物质转运率的结果及均一化值列表
Table 4The evaluation on drought tolerance of 33 hybrids at maize germination stage

材料名称 Hybrids	发芽率 GR (%)	胚芽干重 RDW (g)	贮藏物质转运率 SMTR (%)	发芽率Z值 Z-score of GR	胚芽干重Z值 Z-score of RDW	贮藏物质转运率Z值 Z-score of SMTR	综合Z值 Mean Z-score
郑单958 Zhengdan 958	48	0.0076	5.53	-0.71	-0.55	-1.03	-0.76
吉农大819 Jinongda 819	54	0.0048	5.99	-0.37	-1.18	-0.86	-0.80
登海605 Denghai 605	48	0.0078	4.67	-0.75	-0.50	-1.33	-0.86
吉单551 Jidan 551	43	0.0061	6.40	-1.06	-0.88	-0.72	-0.89
优迪919 Youdi 919	43	0.0058	6.37	-1.06	-0.95	-0.73	-0.91
先玉335 Xianyu 335	92	0.0082	9.73	2.03	-0.41	0.45	0.69
迪卡517 Dika 517	68	0.0129	8.49	0.51	0.66	0.01	0.40
迪卡159 Dika 159	74	0.0174	13.63	0.89	1.67	1.83	1.46
富民108 Fumin 108	61	0.0141	9.46	0.07	0.92	0.36	0.45
富民985 Fumin 985	64	0.0108	12.83	0.30	0.17	1.55	0.67
禾田4号 Hetian 4	81	0.0094	7.94	1.34	-0.13	-0.17	0.34
吉单50 Jidan 50	77	0.0099	5.88	1.08	-0.01	-0.90	0.05
吉单66 Jidan 66	58	0.0087	9.26	-0.11	-0.29	0.28	-0.04
吉单441 Jidan 441	76	0.0079	7.12	1.02	-0.48	-0.46	0.02
吉单505 Jidan 505	50	0.0091	7.86	-0.62	-0.21	-0.20	-0.34
吉单511 Jidan 511	52	0.0267	16.62	-0.49	3.79	2.89	2.06
吉单513 Jidan 513	45	0.0091	6.74	-0.94	-0.21	-0.6	-0.58
吉单53 Jidan 53	19	0.0071	6.60	-2.59	-0.66	-0.65	-1.30
吉单558 Jidan 558	78	0.0156	10.33	1.15	1.26	0.66	1.02
吉单56 Jidan 56	59	0.0138	11.01	-0.05	0.85	0.90	0.56
吉单631 Jidan 631	49	0.0066	4.69	-0.68	-0.77	-1.32	-0.92
吉单96 Jidan 96	55	0.0067	9.17	-0.30	-0.75	0.25	-0.26
吉农大778 Jinongda 778	77	0.0096	7.83	1.08	-0.08	-0.21	0.26
吉农玉719 Jinongyu 719	49	0.0056	6.66	-0.68	-0.99	-0.63	-0.77
金园15 Jinyuan 15	74	0.0079	9.09	0.89	-0.48	0.23	0.21
鹏玉1号 Pengyu 1	57	0.0125	11.92	-0.18	0.57	1.23	0.54
桥玉8号 Qiaoyu 8	53	0.0098	7.05	-0.43	-0.03	-0.49	-0.32
先达203 Xianda 203	80	0.0109	9.27	1.27	0.20	0.29	0.59
翔玉218 Xiangyu 218	49	0.0086	7.91	-0.68	-0.30	-0.19	-0.39
翔玉998 Xiangyu 998	53	0.0076	5.25	-0.43	-0.54	-1.13	-0.70
东农254 Dongnong 254	86	0.0164	13.39	1.65	1.44	1.74	1.61
源丰009 Yuanfeng 009	42	0.0052	5.51	-1.13	-1.08	-1.03	-1.08

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3 讨论

中国的玉米主产区大多分布在干旱、半干旱地区,且多为雨养农业地区,萌发期干旱导致的减产严重影响玉米生长发育进程和产量^[2]。目前,玉米萌发期耐旱相关的研究多采用PEG胁迫模拟干旱。余贵海等^[22]采用20%的PEG溶液模拟干旱,以发芽率、发芽势等性状对14个玉米杂交种进行了耐旱性评价。任杨柳等^[21]以PEG处理254份玉米自交系,通过隶属函数法对发芽率、苗高等性状综合评价苗期耐旱性。除玉米外,许多植物的萌发期耐旱研究也多使用PEG处理开展相关研究^[27,28,29]。尽管PEG模拟干旱是常用的萌发期干旱处理方法,但与实际生产的土壤干旱有一定的差异^[10]。为了研究玉米种子在不同水分胁迫条件下的萌发响应、构建萌发期耐旱性鉴定方法体系,本研究以大田土壤为介质,设置13个土壤含水量梯度,对不同玉米品种的发芽率等相关性状进行测定和分析,建立不同土壤含水量梯度与所测发芽率的Logistic拟合模型,计算限制种子发芽率50%的土壤含水量GW₅₀,为以土壤为介质进行萌发期耐旱鉴定的胁迫强度奠定了基础,验证性试验表明所确立的胁迫强度可有效用于玉米萌发期耐旱鉴定评价。

玉米萌发期耐旱鉴评的相关研究多采用隶属函数法等方法以多指标、多性状进行综合评价,并取得了显著的进展。例如,余贵海等^[22]通过隶属函数法以PEG胁迫条件下发芽率、发芽势、胚根长等性状对14个玉米杂交种进行萌发期耐旱评价。张倩等^[18]以PEG胁迫条件下发芽势、发芽率、胚根长等性状通过隶属函数法对9个玉米杂交种进行萌发期耐旱评价。成锴等^[20]以PEG胁迫条件下发芽率等10个指标的隶属函数值对52个玉米杂交种进行萌发期耐旱的综合评价。任杨柳等^[21]对254份玉米自交系,通过隶属函数法以PEG胁迫条件下发芽率、苗高等性状综合评价苗期耐旱性。针对以上研究提出的性状,进一步探索土壤水分胁迫条件下有效、实用的评价指标显得十分重要。本研究在土壤水分GW₅₀胁迫条件下,对萌发相关的11个性状进行分析,发现发芽率、胚芽干重和贮藏物质转运率具有较高的特征向量和特征值,提出玉米萌发期的发芽率是重要的评价指标性状,结合胚芽干重和贮藏物质转运率就可以较全面地评价玉米萌发期的耐旱性,为确定土培条件下选择适合种子萌发期耐旱性测定性状提供了参考依据。

建立科学实用的玉米抗旱性鉴定评价技术规范,是筛选玉米抗旱种质资源、培育玉米抗旱品种、布局新品种适宜区域的前提和基础。针对玉米苗期、花期、灌浆期的耐旱性已有较多的研究报道,育种家选出了一批耐旱品种,基础研究工作者研究者们挖掘了一些控制耐旱性的遗传位点和基因^{[8,9,10,11,12,13,14,15,16]},取得了显著的进展。萌发期是玉米耐旱的重要时期,本研究构建的玉米品种萌发期耐旱性鉴定评价方法体系,为后续玉米转种质资源及品种的批量规模化鉴定具有重要的意义。同时,所采取的研究思路、试验设计、胁迫处理与条件控制、性状调查、统计分析、鉴定评价指标等方面为后续规范或标准的制定奠定了工作基础。当然,玉米的耐旱性是复杂的数量性状,涉及多种生理机制,又受到不同生育时期、干旱时间、干旱强度的影响,对多个时期的耐旱性进行综合评价鉴定、找出其相互关系及共性机制对全面解析玉米耐旱性,是今后应该加强的重点工作。随着对玉米抗旱性研究的深入和水平的提高,必将对玉米产业产生巨大的推动作用。

4 结论

通过13个土壤含水量梯度与所测定的发芽率拟合的Logistic模型,确定了限制玉米发芽率50%的土壤含水量GW₅₀为18.5%,为适宜的胁迫处理强度;以此为胁迫条件,对32份玉米品种的11个性状进行分析,确立了发芽率、胚芽干重和贮藏物质转运率是萌发期耐旱鉴定的关键指标,可用于通量化玉米萌发期的耐旱鉴定。

参考文献 View Option 原文顺序
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被引期刊影响因子

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[2] 黎裕, 王天宇, 石云素, 宋燕春. 玉米抗旱性的QTL分析研究进展和发展趋势
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LI Y, WANG T Y, SHI Y S, SONG Y C. Current status and perspective of drought resistance QTL in maize
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[3] 王崇桃, 李少昆. 玉米生产限制因素评估与技术优先序
中国农业科学, 2010, 43: 1136-1146.
URL [本文引用: 1]
【Objective】 The aim of this paper was to identify the main limiting factors for realization of maize yield potential and propose the priorities in development of maize production techniques. 【Method】 The limiting factors to maize production in China including potential physical, biological, and institutional factors were summarized through participatory rural appraisal surveys in 13 maize production provinces and three major maize regions in China. Based on the evaluations of influence magnitude and possibility of solution, the priority list for techniques in maize production was obtained. 【Result】 The top first limiting factor was technical problem related to maize cultivation, such as poor tillage management, extensive cultivation, unfavorable fertilization, nonstandard field management during maize growth, and low rate for technique access, resulting in 28.8%-57.7% of yield loss in various maize regions. The second factor was natural stress, especially drought stress, which caused yield loss by 9.3%-35.1%. The third factor, responsible for 11.4%-19.8% of yield loss, was deficiency of staple cultivars for different eco-regions and the technique systems combined with corresponding cultivars. The seed quality was also involved in the third factor. The fourth factor was represented by soil problems, including serious soil erosion, shallow topsoil, and lean soil. Their influence on maize yield was estimated by 4.8%-20.2%. The last limiting factor was pest (disease, insect, rat, and weed, etc.) damage, which caused 4.5%-11.0% of yield loss. 【Conclusion】Therefore, the technique priorities for policy-markers were suggested as labor-saving cultivation techniques; following by high-yielding cultivars with good quality and multiple resistances to bio- and abio-stresses, adaptation to high-density, as well as identification of staple cultivars in various maize regions; mechanization of maize production;and technique popularization in farmers and effect of the techniques used by farmers.


WANG C T, LI S K. Assessment of limiting factors and techniques prioritization for maize production in China
Scientia Agricultura Sinica, 2010, 43: 1136-1146. (in Chinese)
URL [本文引用: 1]
【Objective】 The aim of this paper was to identify the main limiting factors for realization of maize yield potential and propose the priorities in development of maize production techniques. 【Method】 The limiting factors to maize production in China including potential physical, biological, and institutional factors were summarized through participatory rural appraisal surveys in 13 maize production provinces and three major maize regions in China. Based on the evaluations of influence magnitude and possibility of solution, the priority list for techniques in maize production was obtained. 【Result】 The top first limiting factor was technical problem related to maize cultivation, such as poor tillage management, extensive cultivation, unfavorable fertilization, nonstandard field management during maize growth, and low rate for technique access, resulting in 28.8%-57.7% of yield loss in various maize regions. The second factor was natural stress, especially drought stress, which caused yield loss by 9.3%-35.1%. The third factor, responsible for 11.4%-19.8% of yield loss, was deficiency of staple cultivars for different eco-regions and the technique systems combined with corresponding cultivars. The seed quality was also involved in the third factor. The fourth factor was represented by soil problems, including serious soil erosion, shallow topsoil, and lean soil. Their influence on maize yield was estimated by 4.8%-20.2%. The last limiting factor was pest (disease, insect, rat, and weed, etc.) damage, which caused 4.5%-11.0% of yield loss. 【Conclusion】Therefore, the technique priorities for policy-markers were suggested as labor-saving cultivation techniques; following by high-yielding cultivars with good quality and multiple resistances to bio- and abio-stresses, adaptation to high-density, as well as identification of staple cultivars in various maize regions; mechanization of maize production;and technique popularization in farmers and effect of the techniques used by farmers.


[4] 楚杰, 路海东, 薛吉全, 赵明. 玉米宽窄行深旋免耕精量播种机田间试验及效果
农业工程学报, 2014, 14: 34-41.
URL [本文引用: 1]
In the present maize production in China, the problem of agricultural machinery and agronomic technology not supporting the link of maize planting, soil tillage and maize planting has been significantly restricting the increase of maize yield levels and production capability. In order to resolve the problem that the good agronomic practices and agricultural machinery are not currently combined, a new maize planter based on wide-narrow row strip deep rotation and no-tillage technology was used in Weibei dry land in 2011 and 2012. Measured quantities were soil quality, soil moisture, maize emergence rate, field light distribution of maize groups, corn root growth number, and yield traits after this mechanical and ordinary seeder operations in spring corn field. The results show that through adopting the cultivation principle that combined strip-rotating in 40 cm narrow row with no-tillage in 80 cm wide row and integration of excellent seeding technique, deep application of fertilizer, deep rotation technology, no-tillage technology, and wide-narrow row planting technology, the machine can improve soil physical properties and maize population characteristics during the growth period. With the planter seeding, it can effectively break the plough pan and reduce soil bulk density in the 0-30 cm soil layer in narrow deep rotation rows, increasing the mass of maize root, increasing the soil water storage capacity, and significantly enhancing the quality of corn planting groups and population light transmittance. The yield of spring maize and water use efficiency significantly increased after using the planter. The soil bulk density of deep rotation row with precise mechanical sowing of maize based on wide-narrow row strip deep rotation and no-tillage technology is reduced, soil water storage in deep loosening row noticeably improved in later growth stage, soil water content of no-tillage trip with significantly raised in earlier growth stage, the seedling germination rate of maize increased 6.2 percentage points, and the plant height variation coefficient within the field at jointing period decreased 8.33% than those with the ordinary planter. As the same time, root dry weight of maize at the jointing period increased 15.79%, the light intercepted by the population of maize at the later spinning stage significantly increased 22.47%-23.45%, 1000-grain weight increased an average of 3.73%, the effective panicle number per hectare increased an average of 5.84%, and yield increased an average of 11.15% compared with ordinary machine sowing. The combination of good agronomic measures and agricultural machinery is realized in this system, and it can further promote maize grain production and farmers' income in this region.
CHU J, LU H D, XUE J Q, ZHAO M. Field experiment and effect of precise mechanical sowing of maize based on wide-narrow row deep rotation and no-tillage technology
Transactions of the Chinese Society of Agricultural Engineering, 2014, 14: 34-41. (in Chinese)
URL [本文引用: 1]
In the present maize production in China, the problem of agricultural machinery and agronomic technology not supporting the link of maize planting, soil tillage and maize planting has been significantly restricting the increase of maize yield levels and production capability. In order to resolve the problem that the good agronomic practices and agricultural machinery are not currently combined, a new maize planter based on wide-narrow row strip deep rotation and no-tillage technology was used in Weibei dry land in 2011 and 2012. Measured quantities were soil quality, soil moisture, maize emergence rate, field light distribution of maize groups, corn root growth number, and yield traits after this mechanical and ordinary seeder operations in spring corn field. The results show that through adopting the cultivation principle that combined strip-rotating in 40 cm narrow row with no-tillage in 80 cm wide row and integration of excellent seeding technique, deep application of fertilizer, deep rotation technology, no-tillage technology, and wide-narrow row planting technology, the machine can improve soil physical properties and maize population characteristics during the growth period. With the planter seeding, it can effectively break the plough pan and reduce soil bulk density in the 0-30 cm soil layer in narrow deep rotation rows, increasing the mass of maize root, increasing the soil water storage capacity, and significantly enhancing the quality of corn planting groups and population light transmittance. The yield of spring maize and water use efficiency significantly increased after using the planter. The soil bulk density of deep rotation row with precise mechanical sowing of maize based on wide-narrow row strip deep rotation and no-tillage technology is reduced, soil water storage in deep loosening row noticeably improved in later growth stage, soil water content of no-tillage trip with significantly raised in earlier growth stage, the seedling germination rate of maize increased 6.2 percentage points, and the plant height variation coefficient within the field at jointing period decreased 8.33% than those with the ordinary planter. As the same time, root dry weight of maize at the jointing period increased 15.79%, the light intercepted by the population of maize at the later spinning stage significantly increased 22.47%-23.45%, 1000-grain weight increased an average of 3.73%, the effective panicle number per hectare increased an average of 5.84%, and yield increased an average of 11.15% compared with ordinary machine sowing. The combination of good agronomic measures and agricultural machinery is realized in this system, and it can further promote maize grain production and farmers' income in this region.

[5] LU Y, ZHANG S, SHAH T, XIE C, HAO Z, LI X, FARKHARI M, RIBAUT J M, CAO M, RONG T, XU Y. Joint linkage-linkage disequilibrium mapping is a powerful approach to detecting quantitative trait loci underlying drought tolerance in maize
Proceedings of the National Academy of Sciences of the United States of America, 2010, 107(45): 19585-19590.
DOI:10.1073/pnas.1006105107URLPMID:20974948 [本文引用: 2]
This paper describes two joint linkage-linkage disequilibrium (LD) mapping approaches: parallel mapping (independent linkage and LD analysis) and integrated mapping (datasets analyzed in combination). These approaches were achieved using 2,052 single nucleotide polymorphism (SNP) markers, including 659 SNPs developed from drought-response candidate genes, screened across three recombinant inbred line (RIL) populations and 305 diverse inbred lines, with anthesis-silking interval (ASI), an important trait for maize drought tolerance, as the target trait. Mapping efficiency was improved significantly due to increased population size and allele diversity and balanced allele frequencies. Integrated mapping identified 18 additional quantitative trait loci (QTL) not detected by parallel mapping. The use of haplotypes improved mapping efficiency, with the sum of phenotypic variation explained (PVE) increasing from 5.4% to 23.3% for single SNP-based analysis. Integrated mapping with haplotype further improved the mapping efficiency, and the most significant QTL had a PVE of up to 34.7%. Normal allele frequencies for 113 of 277 (40.8%) SNPs with minor allele frequency (<5%) in 305 lines were recovered in three RIL populations, three of which were significantly associated with ASI. The candidate genes identified by two significant haplotype loci included one for a SET domain protein involved in the control of flowering time and the other encoding aldo/keto reductase associated with detoxification pathways that contribute to cellular damage due to environmental stress. Joint linkage-LD mapping is a powerful approach for detecting QTL underlying complex traits, including drought tolerance.

[6] 唐怀君, 谢小清, 张磊, 孙宝成, 周芳芝, 刘成. 应用缺次灌溉和半产需水量模型鉴定玉米杂交种的抗旱性
新疆农业科学, 2018, 55(11): 1994-2001.
[本文引用: 2]

TANG H J, XIE X Q, ZHANG L, SUN B C, ZHOU F Z, LIU C. Identification of drought resistance of maize hybrid by using the model of deficient irrigation and semi-yield water demand
Xinjiang Agricultural Sciences, 2018, 55(11): 1994-2001. (in Chinese)
[本文引用: 2]

[7] 唐怀君, 谢小清, 赵连佳, 孙宝成, 黎裕, 王天宇, 刘成. 欠量灌水方法用于玉米抗旱性鉴定和评价研究
新疆农业科学, 2017, 54(5): 804-810.
[本文引用: 2]

TANG H J, XIE X Q, ZHAO L J, SUN B C, LI Y, WANG T Y, LIU C. Study on the evaluation and identification of maize drought resistance by using the method of water shortage irrigation
Xinjiang Agricultural Sciences, 2017, 54(5): 804-810. (in Chinese)
[本文引用: 2]

[8] MAO H, WANG H W, LIU SH X, LI Z G, YANG X H, YAN J B, LI J S, TRAN L S P, QIN F. A transposable element in a NAC gene is associated with drought tolerance in maize seedlings
Nature Communications, 2015, 6: 8326.
DOI:10.1038/ncomms9326URLPMID:26387805 [本文引用: 3]
Drought represents a major constraint on maize production worldwide. Understanding the genetic basis for natural variation in drought tolerance of maize may facilitate efforts to improve this trait in cultivated germplasm. Here, using a genome-wide association study, we show that a miniature inverted-repeat transposable element (MITE) inserted in the promoter of a NAC gene (ZmNAC111) is significantly associated with natural variation in maize drought tolerance. The 82-bp MITE represses ZmNAC111 expression via RNA-directed DNA methylation and H3K9 dimethylation when heterologously expressed in Arabidopsis. Increasing ZmNAC111 expression in transgenic maize enhances drought tolerance at the seedling stage, improves water-use efficiency and induces upregulation of drought-responsive genes under water stress. The MITE insertion in the ZmNAC111 promoter appears to have occurred after maize domestication and spread among temperate germplasm. The identification of this MITE insertion provides insight into the genetic basis for natural variation in maize drought tolerance.

[9] WANG X L, WANG H W, LIU S X, FERJANI A, LI J S, YAN J B, YANG X H, QIN F. Genetic variation in ZmVPP1 contributes to drought tolerance in maize seedlings
Nature Genetics, 2016, 10: 3636.
[本文引用: 3]

[10] BLUM A. Genomics for drought resistance-getting down to earth
Functional Plant Biology, 2014, 41(11): 1191.
DOI:10.1071/FP14018URLPMID:32481068 [本文引用: 4]
A meta-analysis of 520 reports published during the last 20 years on transgenic and mutant plants generated towards drought resistance revealed a total of at least 487 tested transgenic plants involving at least 100 genes claimed to be functional towards drought resistance. During this period, the rate of reported new experimental transgenic model or crop plants for drought resistance has been increasing exponentially. Despite these numbers, qualified sources of information indicate a very limited impact on global dryland agriculture, whereas the genetically modified (GM) market hardly recognises drought-resistant GM cultivars. This paper discusses possible reasons for the limited impact of genomics on the delivery of drought-resistant cultivars, which are beyond issues of regulation, propriety or commercialisation. These reasons are mainly tied to scientific and methodological problems in drought stress gene expression work and the functional genomics protocols used to identify drought resistance. Insufficient phenotyping of experimental transgenic plants for drought resistance often does not allow true conclusions about the real function of the discovered genes towards drought resistance. The discussion is concluded by proposing an outline of a minimal set of tests that might help us resolve the real function of discovered genes, thus bringing the research results down to earth.

[11] ZHENG J, FU J, GOU M, HUAI J, LIU Y, JIAN M, HUANG Q, GUO X, DONG Z, WANG H, WANG G. Genome-wide transcriptome analysis of two maize inbred lines under drought stress
Plant Molecular Biology, 2010, 72(4/5): 407-421.
[本文引用: 2]

[12] HALL A J, VILELLA F, TRAPANI N, CHIMENTI C. The effects of water stress and genotype on the dynamics of pollen-shedding and silking in maize
Field Crops Research, 1982, 5: 349-366.
DOI:10.1016/0378-4290(82)90036-3URL [本文引用: 2]

[13] EDMEADES G O, BOLANOS J, HERNANDEZ M, BELLO S. Causes for silk delay in a lowland tropical maize population
Crop Science, 1993, 33(5): 1029.
[本文引用: 2]

[14] LU Y, HAO Z, XIE C, CROSSA J, ARAUS J L, GAO S, VIVEK B, MAGOROKOSHO C, MUGO S, MAKUMBI D, TABA S, PAN G, LI X, RONG T, ZHANG S, XU Y. Large-scale screening for maize drought resistance using multiple selection criteria evaluated under water-stressed and well-watered environments
Field Crops Research, 2011, 124: 37-45.
DOI:10.1016/j.fcr.2011.06.003URL [本文引用: 2]

[15] FU F, FENG Z, GAO S, ZHOU S, LI W. Evaluation and quantitative inheritance of several drought-relative traits in maize
Agricultural Sciences in China, 2008, 7(3): 280-290.
[本文引用: 2]

[16] LI C, SUN B, LI Y, LIU C, WU X, ZHANG D, SHI Y, SONG Y, BUCKLER E S, ZHANG Z, WANG T, LI Y. Numerous genetic loci identified for drought tolerance in the maize nested association mapping populations
BMC Genomics, 2016, 17: 894.
DOI:10.1186/s12864-016-3170-8URLPMID:27825295 [本文引用: 2]
BACKGROUND: Maize requires more water than most other crops; therefore, the water use efficiency of this crop must be improved for maize production under undesirable land and changing environmental conditions. RESULTS: To elucidate the genetic control of drought in maize, we evaluated approximately 5000 inbred lines from 30 linkage-association joint mapping populations under two contrasting water regimes for seven drought-related traits, including yield and anthesis-silking interval (ASI). The joint linkage analysis was conducted to identify 220 quantitative trait loci (QTLs) under well-watered conditions and 169 QTLs under water-stressed conditions. The genome-wide association analysis identified 365 single nucleotide polymorphisms (SNPs) associated with drought-related traits, and these SNPs were located in 354 candidate genes. Fifty-two of these genes showed significant differential expression in the inbred line B73 under the well-watered and water-stressed conditions. In addition, genomic predictions suggested that the moderate-density SNPs obtained through genotyping-by-sequencing were able to make accurate predictions in the nested association mapping population for drought-related traits with moderate-to-high heritability under the water-stressed conditions. CONCLUSIONS: The results of the present study provide important information that can be used to understand the genetic basis of drought stress responses and facilitate the use of beneficial alleles for the improvement of drought tolerance in maize.

[17] 徐明慧, 于晓东, 马兴林, 关义新. 水分胁迫对玉米萌芽期贮藏物质利用效率的影响
作物杂志, 2004, 6: 11-13.
[本文引用: 1]

XU M H, YU X D, MA X L, GUAN Y X. Effect of water stress on storage substance utilization at maize germination stage
Crops, 2004, 6: 11-13. (in Chinese)
[本文引用: 1]

[18] 张倩, 张洪生, 盖伟玲, 段梅堂, 姜雯. 玉米品种早期抗旱性分析
山东农业科学, 2011, 2: 21-23.
URL [本文引用: 2]
对山东省主推的9个玉米品种进行了萌发期PEG模拟水分胁迫试验.结果表明:水分胁迫对每个玉米品种的发芽势、发芽率、胚根长、胚根干重等都有影响,但不同杂交种在抗旱性上存在明显差异.本研究使用隶属函数法对参试材料抗旱性进行了定量评价,其中莱农14、农大108、登海701为早期典型抗旱型品种;浚单20、金海5号、青农105、中科11为早期较抗旱型品种;登海662、郑单958为早期不抗旱型品种.其它各抗旱筛选指标中,种子萌发抗旱指数与隶属函数对品种抗旱性分析结果较为一致.
ZHANG Q, ZHANG H S, GAI W L, DUAN M T, JIANG W. Drought resistance analysis of maize varieties at germination stage
Shandong Agricultural Sciences, 2011, 2: 21-23. (in Chinese)
URL [本文引用: 2]
对山东省主推的9个玉米品种进行了萌发期PEG模拟水分胁迫试验.结果表明:水分胁迫对每个玉米品种的发芽势、发芽率、胚根长、胚根干重等都有影响,但不同杂交种在抗旱性上存在明显差异.本研究使用隶属函数法对参试材料抗旱性进行了定量评价,其中莱农14、农大108、登海701为早期典型抗旱型品种;浚单20、金海5号、青农105、中科11为早期较抗旱型品种;登海662、郑单958为早期不抗旱型品种.其它各抗旱筛选指标中,种子萌发抗旱指数与隶属函数对品种抗旱性分析结果较为一致.

[19] 孙军伟, 冀天会, 杨子光, 孟丽梅, 张珂, 宋韶帅. 玉米萌芽期抗旱性鉴定研究
中国农学通报, 2009, 25, 3: 104-107.
URL [本文引用: 1]
Maize; Seedling emergence stage; Drought resistant; GDRI
SUN J W, JI T H, YANG Z G, MENG L M, ZHANF K, SONG S S. Study on identification of the drought resistant in maize seedling emergence stage
Chinese Agricultural Science Bulletin, 2009, 25, 3: 104-107. (in Chinese)
URL [本文引用: 1]
Maize; Seedling emergence stage; Drought resistant; GDRI

[20] 成锴, 苏晓慧, 栗建枝, 赵太存, 王国梁, 李洪. PEG-6000胁迫下玉米品种萌发期抗旱性鉴定与评价
玉米科学, 2017, 25(5): 85-90.
[本文引用: 2]

CHENG K, SU X H, LI J Z, ZHAO T C, WANG G L, LI H. Identification and evaluation of maize drought resistance under PEG-6000 stress at germination stage
Journal of Maize Sciences, 2017, 25(5): 85-90. (in Chinese)
[本文引用: 2]

[21] 任杨柳, 乔大河, 胡春辉, 张龙, 李玉玲. 不同种质玉米自交系种子萌发的干旱胁迫
中国农学通报, 2017, 33(9): 17-21.
[本文引用: 3]

REN Y L, QIAO D H, HU C H, ZHANG L, LI Y L. Drought stress on different maize inbred lines at germination stage
Chinese Agricultural Science Bulletin, 2017, 33(9): 17-21. (in Chinese)
[本文引用: 3]

[22] 余贵海, 起雪宏, 王正启, 赵自仙, 杨久. 14个玉米杂交种萌发期抗旱性评价
西南农业学报, 2016, 29(7): 1499-1505.
[本文引用: 3]

YU G H, Qi X H, WANG Z Q, ZHAO Z X, YANG J. Evaluation of drought resistance for 14 corn hybrids at seed germination stage
Southwest China Journal of Agricultural Sciences, 2016, 29(7): 1499-1505. (in Chinese)
[本文引用: 3]

[23] 郝楠, 王延波, 李月明. 温度对玉米种子萌发特性的影响
玉米科学, 2013, 4: 59-63.
[本文引用: 1]

HAO N, WANG Y B, LI Y M. Effect of temperature on seed germination and physiological character of maize hybrid
Journal of Maize Sciences, 2013, 4: 59-63. (in Chinese)
[本文引用: 1]

[24] 高星, 李永祥, 杨明涛, 李琲琲, 李春辉, 宋燕春, 张登峰, 王天宇, 黎裕, 石云素. 基于高密度遗传图谱的玉米籽粒灌浆特性遗传解析
中国农业科学, 2017, 50(21): 4087-4099.
DOI:10.3864/j.issn.0578-1752.2017.21.003URL [本文引用: 1]
【目的】灌浆是玉米籽粒形成的重要生理过程,直接决定了籽粒的最终产量。了解玉米籽粒灌浆特性相关性状对粒重形成的作用,解析灌浆特性的遗传基础,为玉米高产育种实践提供指导。【方法】以中国玉米骨干自交系黄早四（HZS）、旅28（Lv28）为亲本构建的包含172个家系的重组自交系（recombination inbred line,RIL）群体为试验材料。首先,利用Logistic模型与Richards模型,进行玉米籽粒灌浆过程拟合度的比较分析。其次,利用方差分析、相关性分析及回归分析分别比较亲本籽粒灌浆特性的差异,研究群体中不同灌浆特性相关性状的关系及其对百粒重的贡献。然后,利用GBS方法,对群体进行基因型分型,选择亲本间多态性标记,构建遗传图谱。最后,利用完备区间作图法（inclusive composite interval mapping,ICIM）进行灌浆特性与生育期相关性状的QTL分析。【结果】籽粒灌浆一般呈现慢-快-慢的变化趋势,可分为缓增期、快增期以及减缓期3个阶段。通过比较不同灌浆模型的拟合度发现,基于Richards模型的预测值与表型值间的决定系数显著高于Logistic模型。比较亲本间灌浆特性的差异发现,黄早四的平均灌浆速率为旅28的1.28倍,但旅28的灌浆持续时间为黄早四的1.07倍,亲本之间在灌浆特性方面差异明显。群体表型相关性分析发现,除缓增期灌浆持续时间（T₁）外,其他灌浆特性相关性状均与百粒重（HKW）存在显著的正相关关系。回归分析发现,快增期灌浆持续时间（T₂）与灌浆速率（G₂）可分别解释百粒重表型变异的57.50%和30.00%。利用多态性SNP标记构建了全长为1 471 cM,标记间平均遗传图距为1 cM的遗传图谱。多个环境下共检测到26个灌浆特性相关QTL、3个百粒重相关QTL及14个生育期相关的QTL,分布在玉米除第7染色体外的其他染色体上,LOD值介于3.27—9.05,单个QTL贡献率为5.97%—21.16%。同时,利用联合环境分析发现,控制不同性状的QTL定位在染色体相同或相近的位置,形成了多个分布于玉米基因组bin 1.05、bin 2.03、bin 4.05、bin 4.06、bin 7.04、bin 9.04的QTL富集区域。其中,在位于bin 4.05（48.24 Mb—135.73 Mb）和bin 9.04（110.40 Mb—114.73 Mb）的区间之内,共定位到多个仅与灌浆速率相关的主效QTL。【结论】Richards模型能够更好地模拟玉米籽粒的灌浆过程。在灌浆特性相关性状中,快增期灌浆速率与灌浆持续时间对于玉米粒重的增加具有重要作用。单环境检测发现,灌浆持续时间相关位点仅能在单环境中得以检测,表现为环境敏感类型。联合环境分析发现,在bin 4.05和bin 9.04区间内分别检测到仅与灌浆速率相关的主效QTL,可作为玉米籽粒灌浆研究的重点区域。
GAO X, LI Y X, YANG M T, LI B B, LI C H, SONG Y C, ZHANG D F, WANG T Y, LI Y, SHI Y S. Genetic dissection of grain filling related traits based on a high-density map in maize
Scientia Agricultura Sinica, 2017, 50(21): 4087-4099. (in Chinese)
DOI:10.3864/j.issn.0578-1752.2017.21.003URL [本文引用: 1]
【目的】灌浆是玉米籽粒形成的重要生理过程,直接决定了籽粒的最终产量。了解玉米籽粒灌浆特性相关性状对粒重形成的作用,解析灌浆特性的遗传基础,为玉米高产育种实践提供指导。【方法】以中国玉米骨干自交系黄早四（HZS）、旅28（Lv28）为亲本构建的包含172个家系的重组自交系（recombination inbred line,RIL）群体为试验材料。首先,利用Logistic模型与Richards模型,进行玉米籽粒灌浆过程拟合度的比较分析。其次,利用方差分析、相关性分析及回归分析分别比较亲本籽粒灌浆特性的差异,研究群体中不同灌浆特性相关性状的关系及其对百粒重的贡献。然后,利用GBS方法,对群体进行基因型分型,选择亲本间多态性标记,构建遗传图谱。最后,利用完备区间作图法（inclusive composite interval mapping,ICIM）进行灌浆特性与生育期相关性状的QTL分析。【结果】籽粒灌浆一般呈现慢-快-慢的变化趋势,可分为缓增期、快增期以及减缓期3个阶段。通过比较不同灌浆模型的拟合度发现,基于Richards模型的预测值与表型值间的决定系数显著高于Logistic模型。比较亲本间灌浆特性的差异发现,黄早四的平均灌浆速率为旅28的1.28倍,但旅28的灌浆持续时间为黄早四的1.07倍,亲本之间在灌浆特性方面差异明显。群体表型相关性分析发现,除缓增期灌浆持续时间（T₁）外,其他灌浆特性相关性状均与百粒重（HKW）存在显著的正相关关系。回归分析发现,快增期灌浆持续时间（T₂）与灌浆速率（G₂）可分别解释百粒重表型变异的57.50%和30.00%。利用多态性SNP标记构建了全长为1 471 cM,标记间平均遗传图距为1 cM的遗传图谱。多个环境下共检测到26个灌浆特性相关QTL、3个百粒重相关QTL及14个生育期相关的QTL,分布在玉米除第7染色体外的其他染色体上,LOD值介于3.27—9.05,单个QTL贡献率为5.97%—21.16%。同时,利用联合环境分析发现,控制不同性状的QTL定位在染色体相同或相近的位置,形成了多个分布于玉米基因组bin 1.05、bin 2.03、bin 4.05、bin 4.06、bin 7.04、bin 9.04的QTL富集区域。其中,在位于bin 4.05（48.24 Mb—135.73 Mb）和bin 9.04（110.40 Mb—114.73 Mb）的区间之内,共定位到多个仅与灌浆速率相关的主效QTL。【结论】Richards模型能够更好地模拟玉米籽粒的灌浆过程。在灌浆特性相关性状中,快增期灌浆速率与灌浆持续时间对于玉米粒重的增加具有重要作用。单环境检测发现,灌浆持续时间相关位点仅能在单环境中得以检测,表现为环境敏感类型。联合环境分析发现,在bin 4.05和bin 9.04区间内分别检测到仅与灌浆速率相关的主效QTL,可作为玉米籽粒灌浆研究的重点区域。

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