玉米苗期耐旱材料筛选及QTL定位  

Maize drought-tolerant material screening and QTL localization in the seedling stage

作　　者：周玉梅 庄泽龙 郭海 杨小雯 雷恭鑫 彭云玲 ZHOU Yumei;ZHUANG Zelong;GUO Hai;YANG Xiaowen;LEI Gongxin;PENG Yunling(College of Agronomy,Gansu Agricultural University,Key Laboratory of Arid Land Crop Science in Gansu Prov-ince,Gansu Key Laboratory of Crop Improvement and Germplasm Enhancement,Lanzhou 730070,China)

机构地区：[1]甘肃农业大学农学院,甘肃省干旱生境作物学重点实验室,甘肃省作物遗传改良与种质创新重点实验室,甘肃兰州730070

出　　处：《甘肃农业大学学报》2024年第5期55-64,共10页Journal of Gansu Agricultural University

基　　金：兰州市科技局项目(2020-RC-122);中央引导地方科技发展专项基金项目(ZCYD-2021)。

摘　　要：【目的】在PEG-6000(Macrogol 6000,聚乙二醇-6000)模拟干旱条件下,评价和筛选出DH(Doubled Haploid,双单倍体)群体的耐旱玉米材料,并对该群体耐旱相关性状进行QTL(Quantitative Trait Locus,数量性状基因座)定位,为材料筛选以及后续玉米耐旱性的遗传研究提供基础。【方法】本试验以127份DH群体材料为试验材料,在20%PEG-6000干旱胁迫下通过测定其幼苗期SPAD(Soil and Plant Analyzer Development,叶绿素含量)、茎粗、苗长、地上鲜质量、地上干质量、SOD(Superoxide Dismutase,超氧化物歧化酶)、POD(Peroxidase,过氧化物酶)以及CAT(Catalase,过氧化氢酶)指标,得出综合耐旱指数,并通过聚类分析和逐步回归方程来综合评价其耐旱性及筛选耐旱材料,运用完备区间作图定位法进行耐旱QTL定位。【结果】将127份材料分为强耐旱、较强耐旱、耐旱、不耐旱材料4个类群,筛选到强耐旱材料1份,较强耐旱材料7份,耐旱材料17份,不耐旱材料102份;在第5条染色体上检测到2个QTL,与玉米耐旱性状指标叶绿素相关的位点命名为qSPAD-5,LOD值(Likelihood of odd,极大似然函数比的常用对数)为4.810 7,表型贡献率为2.291 1%;与地上鲜质量相关的位点命名为qFWAG-5,LOD值为2.520 5,表型贡献率为5.286 9%。【结论】在PEG-6000模拟干旱条件下,材料405表现出了极强的耐旱性,是筛选出的强耐旱性材料,且SOD、地上鲜质量、CAT可作为玉米耐旱性鉴定的指标。其中在5号染色体上检测到2个QTL与耐旱性状SPAD和地上鲜质量相关,分别为qSPAD-5和qFWAG-5。【Objective】The study aimed to evaluate and screen drought-tolerant maize materials from DH(Doubled Haploid)population under the simulated drought conditions by using PEG-6000(Macrogol 6000)and to localize QTL(Quantitative Trait Locus)for the drought-tolerance-related traits,laying a research basis for further material screening and subsequent genetic studies on drought tolerance in maize.【Method】In this experiment,127 DH populations were tested under drought stress with 20%PEG-6000.The SPAD(Soil and Plant Analyzer Development),stem thickness,seedling length,above-ground fresh weight,above-ground dry weight,SOD(Superoxide Dismutase),POD(Peroxidase)and CAT(Catalase)indexes were measured at the seedling stage to obtain a comprehensive drought tolerance index,followed by comprehensively evaluating their drought tolerance and screening for drought-tolerant materials by using cluster analysis and stepwise regression analysis,and then drought tolerance QTL localization was performed by the way of the complete interval mapping localization.【Result】The 127 materials were divided into four groups:strong drought-tolerant,lightly strong drought-tolerant,drought-tolerant and non-drought tolerant materials,and one strongly drought-tolerant material,7 lightly strong drought-tolerant materials,17 drought-tolerant materials and 102 non-drought-tolerant materials were obtained.Two QTLS were detected on the chromosome 5,and the loci related to the drought-tolerant trait indicator(i.e.,the chlorophyll)was named as qSPAD-5,with LOD(Likelihood of odd)value of 4.8107 and phenotypic contribution rate of 2.2911%.The locus associated with aboveground fresh weight was named as qFWAG-5,with LOD value of 2.5205 and phenotypic contribution rate of 5.2869%.【Conclusion】Under the simulated drought condition of PEG-6000,material 405 was screened as the strong drought-tolerant material due to its strong drought tolerance,and its SOD,above-ground fresh weight and CAT could be used as the indicators for drought tolerance identificati

关 键 词：玉米 耐旱性 幼苗期 筛选 QTL 

分 类 号：S513[农业科学—作物学]