中国农业科学 ›› 2020, Vol. 53 ›› Issue (19): 3867-3877.doi: 10.3864/j.issn.0578-1752.2020.19.002

• 作物遗传育种·种质资源·分子遗传学 • 上一篇    下一篇

土培条件下玉米萌发期耐旱鉴评技术体系研究

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1()   

  1. 1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
  • 收稿日期:2019-11-03 接受日期:2020-04-08 出版日期:2020-10-01 发布日期:2020-10-19
  • 通讯作者: 王天宇,李晓辉
  • 作者简介:张春宵,E-mail: chunxiao1000@126.com。|李淑芳,E-mail: xlsf@163.com。|刘旭洋,E-mail: 1021247118@qq.com
  • 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)

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

ZHANG ChunXiao1(),LI ShuFang1(),LIU XuYang2(),LIU Jie1,LIU WenPing1,LIU XueYan1,LI ChunHui2,WANG TianYu2(),LI XiaoHui1()   

  1. 1Crop Germplasm Resources Institute, Jilin Academy of Agricultural Sciences, Gongzhuling 136100, Jilin
    2Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081
  • Received:2019-11-03 Accepted:2020-04-08 Online:2020-10-01 Published:2020-10-19
  • Contact: TianYu WANG,XiaoHui LI

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.

Key words: maize (Zea mays L.), germination stage, soil drought, drought tolerance, evaluation system