Temporal genetic patterns of root growth in Brassica napus L. revealed by a low-cost, high-efficiency hydroponic system

Genome-Wide Association Study and Transcriptome Analysis Reveal Key Genes Affecting Root Growth Dynamics In Rapeseed

“…The principal component analysis (PCA) of all the investigated traits were conducted by the software SAS 9.2. The first step of PCA was to obtain the correlation matrix between different traits, then the dimensionality reduction was performed to obtain eight principal components, and PC1 and PC2 were plotted by R. According to previous reported method (Wang et al 2019b), the growth rate (GR) of accession sample was calculated as the root fresh weight (RFW) value at the late stage minus that at the early stage, and then divided by the growing days. GR of an accession was normalized according to the following formula.…”

“…The previously reported hydroponic system was used for the root-related trait evaluation of the 280 B. napus accessions (Wang et al 2019b). Briefly, uniform and stout rapeseed seeds were placed on the medical gauze of the germination device for 2 d in the dark, then they grew in the light (180 μmol photons m −2 •s −1 ) for 4 d in a greenhouse (60-80% relative humidity) under 16/8 h day/night cycles at 24°C (Fig.…”

“…To breed the crops with better RSA, a large number of studies have focused on variations in root architecture in many crops, such as rice, wheat, maize, soybean, and rapeseed (Burton et al 2014;Song et al 2016a;Beyer et al 2019;Wang et al 2019b;Guo et al 2020). Several studies have identified hundreds of root QTL in controlled environments or in the field (Song et al 2016b;Wang et al 2017Wang et al , 2019aWang et al , 2019b.…”

“…To breed the crops with better RSA, a large number of studies have focused on variations in root architecture in many crops, such as rice, wheat, maize, soybean, and rapeseed (Burton et al 2014;Song et al 2016a;Beyer et al 2019;Wang et al 2019b;Guo et al 2020). Several studies have identified hundreds of root QTL in controlled environments or in the field (Song et al 2016b;Wang et al 2017Wang et al , 2019aWang et al , 2019b. Besides, several of these QTL have also been reported to influence such traits as yield, water/nutrient uptake, and abiotic stress tolerance (Hua et al 2016;Song et al 2016b;Gong and McDonald 2017;Fan et al 2018;Bernardino et al 2019;Schierholt et al 2019;Islam et al 2021).…”

“…A previous study has defined seven root growth types in a B. napus recombinant inbred line (RIL) population derived from two rapeseed cultivars (Zhongshuang11 and NO. 73290) with contrasting root systems, and identified two types of QTL (persistent and stage-specific) by the analysis of root traits in rapeseed (Wang et al 2019b). To further identify the genetic factors controlling the dynamic root growth, we examined five continuous stages during root development in 280 natural accessions of B. napus.…”