基于GGE双标图的谷子种质资源耐旱性鉴定

Drought Tolerance Identification of Foxtail Millet Germplasm Resources Based on GGE Biplot

为探讨谷子全生育期耐旱性鉴定的有效方法,筛选谷子全生育期耐旱性鉴定指标,加快谷子耐旱育种进程,2019—2020年以30份谷子种质为试材,采用随机不完全区组设计(alpha-格子设计),设干旱胁迫(DS)和正常供水(CK)2个处理,考察相关农艺性状和产量指标的耐旱系数。联合方差分析结果表明,土壤水分环境对千粒质量影响显著,对其他指标影响极显著,基因型对单株穗质量和单株粒质量影响显著,对其他指标影响极显著,基因型与土壤水分环境互作极显著影响谷子的生长性状,对产量性状的影响不显著(千粒质量除外)。在干旱胁迫下,各指标性状值较CK均发生不同程度下降,且各指标性状对干旱胁迫反应的敏感性不同。t检验结果表明,干旱胁迫处理效果显著(千粒质量除外)。GGE双标图解释了数据总变异的71.15%,各指标耐旱系数间存在不同程度的相关性,其中株高、穗长、茎叶干质量和倒二叶叶面积的耐旱系数显著正相关,穗质量、穗粒质量、穗粒数和产量的耐旱系数显著正相关。谷子的耐旱性可以通过不同的农艺性状体现。依据与理想耐旱品种和理想耐旱鉴定指标的距离对供试谷子材料耐旱性和耐旱评价指标进行了排序,其中太选26号、朝谷62号和朝谷13号等材料耐旱性较强,株高和穗质量可作为谷子全生育期耐旱性鉴定首选指标。GGE双标图为谷子耐旱品种选育提供了一个客观有效的新的可视化鉴定方法。

In order to explore the effective methods for the identification of drought tolerance of foxtail millet during the entire growth period,select the identification indices of drought tolerance of foxtail millet,and speed up the process of drought tolerance breeding of foxtail millet,a field experiment was conducted using a randomized incomplete block design(alpha-lattice design)and repeated thrice in 2019—2020.Each experiment consisted of 30 foxtail millet genotypes treated under drought stress(DS)and normal water supply(CK).The agronomic traits and drought tolerance coefficient(DC)of the genotypes were assessed during the entire growth period.Combined analysis of variance showed that soil water environment had significant effects on 1000-grain weight,and extremely significant effects on the other indices.Genotype had significant effects on spike weight and grain weight per plant,and extremely significant effects on the other indices.Besides,the interaction between genotype and soil water environment extremely significantly affected the growth traits of foxtail millet,but not yield traits(except 1000-grain weight).Under drought stress,the characteristic value of each index decreased in varying degrees compared with CK,and the sensitivity of each index to drought stress was different.The results of t test showed that the effect of drought stress was significant(except 1000-grain weight).GGE biplot explained 71.15%of the total variation of data.The drought tolerance coefficient of each index was correlated in different degrees,in which the drought tolerance coefficients of plant height,spike length,stem and leaf dry weight and top second leaf area were significant positive correlation,and that of spike weight per plant,grain weight per plant,kernels per spike and yield were also significant positive correlation.The drought tolerance of foxtail millet could be reflected by different agronomic traits.According to the distance from ideal drought-tolerant varieties and ideal drought-tolerant evaluation indices,the drought tolerance and evaluation indices of foxtail millet materials were ranked.Taixuan 26,Chaogu 62,Chaogu 13 and other materials had strong drought resistance,plant height and spike weight per plant could be used as indices for drought tolerance identification in foxtail millet.GGE biplot provided an objective and effective new visual identification method for the breeding of drought resistant foxtail millet varieties.