Modelling of Genotype × Environment interaction for grain yield of late maturity maize hybrids in Serbia by climate variables

Abstract

With global climate change, including unpredictable geographic and temporal weather patterns causing significant Genotype × Environment interaction (GEI), modelling by climate variables can reveal their influence on phenophases of maize (Zea mays L.) development. The objectives of this study were dissection of the phenotypic variation of grain yield of late maturity maize hybrids grown in multi-environment trial, and quantification of the influence of climatic factors on the GEI for each vegetative and reproductive phenophase. Eight FAO 700 maize hybrids were evaluated across five locations in Serbia during 2020 and 2021 years. The hierarchy of sources of variation according to three-way ANOVA were: Year (Y) > Location (L) > Location×Genotype (G) > L×Y×G > G > L×Y > Y×G. The average maximum temperature (mxt, 22.1%), average minimum temperature (mnt, 19.2%), average mean temperature (mt, 18.2%) and relative humidity (rh, 15.1%) in April significantly influenced emergence stage. The mxt (21.1%) and mt (15.7%) in May influenced significantly vegetative phases V1-V9. June contributed the largest percentage of the sum of squares of the GEI with mxt (25.2%), mnt (20.9%), mt (16.1%) influencing vegetative phases V10-V18 and tassel emergence. In July mxt (17%), mt (15.6%), precipitation sum (15.2%), and sunshine hours sum (15.1%), influenced R1, R2, R3, and R4 reproductive phases. In August mxt (23.2%), mnt (20.8%), mt (15.7%), rh (17.1%) influenced R5 reproductive phase. The extreme heat as a stressor had a more critical role for late maturity maize hybrids production than drought in crucial phenophases of maize development.