AUTHOR=Liu Ce , Liu Xiaoxiao , Han Yike , Wang Xi'ao , Ding Yuanyuan , Meng Huanwen , Cheng Zhihui 

TITLE=Genomic Prediction and the Practical Breeding of 12 Quantitative-Inherited Traits in Cucumber (Cucumis sativus L.)

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 12 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.729328

DOI=10.3389/fpls.2021.729328

ISSN=1664-462X

ABSTRACT=Genomic prediction is an effective way for predicting complex traits, and it is becoming more essential in horticulture crop breeding. In our work, we applied genomic prediction in breeding of cucumber plants. Eighty-one cucumber inbred lines were genotyped and 16,662 markers were identified to represent the genetic background of cucumber. Two populations i.e. Diallel cross (DC) and North Carolina II (NC) having 268 combinations in total were constructed from 81 inbred lines. Twelve cucumber commercial traits of these two populations in autumn 2018, spring 2019, and spring 2020 were collected for model training. General combining ability (GCA) models under five-folds cross validation and cross populations validation were applied to model validation. Finally, the GCA performance of 81 inbred lines were estimated. Our results showed that the predictive ability for 12 traits ranged from 0.38 to 0.95 under cross validation strategy, and ranged from -0.38 to 0.88 under cross populations strategy. Besides, GCA models containing non-additive effects had significantly better performance than pure additive GCA model for most of the investigated traits. Furthermore, there were a relatively higher proportion of additive-by-additive genetic variance components estimated by the full GCA model, especially for lower heritability traits, but the proportion of dominant genetic variance components was relatively small and stable. Our findings concluded that a genomic prediction protocol based on GCA model theoretical framework can be applied to cucumber breeding, and it can also provide a reference for the single-cross breeding system of other crops.