Comparison of leaf transcriptomes of cassava “Xinxuan 048” diploid and autotetraploid plants

Abstract

Polyploidy breeding of cassava has been used to improve cassava traits over the past years. We previously reported in vitro induction of tetraploids in the cassava variety "Xinxuan 048" using colchicine. Significant differences in morphology and anatomy were found between the diploid and tetraploid plants. However, very little is known about the transcriptome difference between them. In this study, morphological and physiological characteristics including leaf thickness, plant height, internode length, chlorophyll content, and photosynthetic capacity were measured. Further, we investigated and validated the difference in gene expression patterns between cassava "Xinxuan 048" tetraploid genotype and its diploid plants using RNA sequencing (RNAseq) and quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Significant differences in morphology and physiology were observed during tetraploidization. A comparison revealed that tetraploidy induced very limited changes in the leaf transcriptomes of cassava "Xinxuan 048" diploid and autotetraploid plants. However, the differentially expressed genes (DEGs) between 2× and 4× plants, especially those upregulated in 4× plants, were strongly associated with hormonal and stress responses. Large changes in morphology and physiology between the diploid cassava "Xinxuan 048" and its autotetraploid were not associated with large changes in their leaf transcriptomes. Moreover, the differently expressed genes related to the regulation of gibberellin and brassinosteroids potentially explained why the plant height and internode length of 4× plants became shorter. Collectively, our results suggest that 4× cassava is potentially valuable for breeding strains with improved stress resistance.

Expression pattern of resynthesized allotetraploid Capsella is determined by hybridization, not whole‐genome duplication

“…WGD often has a limited immediate impact on gene expression patterns in synthetic autopolyploids, affecting the expression of a small fraction (< 1%) of genes (Galitski et al ., 1999 ; Wang et al ., 2006 ; Allario et al ., 2011 ), or affecting a larger fraction of genes but with few expression changes larger than twofold (Stupar et al ., 2007 ; Riddle et al ., 2010 ; Yu et al ., 2010 ; Yin et al ., 2018 ). Moderate levels of expression changes were also found in some autopolyploids, where 2–5% of genes showed an FC larger than two (Wu et al ., 2014 ; Dai et al ., 2015 ; Xiang et al ., 2019 ).…”

Induction of Synthetic Polyploids and Assessment of Genomic Stability in Lippia alba

“…The induction of polyploids has been widely used as a strategy to investigate the effects of artificial genomic duplication on several plant species. Morphological, histological, physiological, agronomic, and genomic traits have been evaluated in different studies (Adams and Wendel, 2005;Buggs et al, 2008;Rêgo et al, 2011;Hegarty et al, 2013;Gomes et al, 2014;Tavan et al, 2015;Gao et al, 2016;Iannicelli et al, 2016;Yan et al, 2016;Sadat-Noori et al, 2017;Salma et al, 2017;Zhou et al, 2017). Although polyploidy induction has been widely recognized as an important strategy for chromosome duplication in plants, the protocols are still associated with low efficiency.…”

Induced Autotetraploids in <i>Salvia miltiorrhiza</i> and Their Agronomic Traits

“…MDA contents of autotetrapoidy S. miltiorrhiza were lower than diploid control (p<0.01, p<0.05), except for TY22 and TY62 (Table 4). Polyploidy plants show superior resistance ability to environmental stresses (Kaensaksiri et al 2011), that may be the expression level of genes associated with hormonal and stress responses upregulated in autotetraploid plants (Yin et al 2018). As a result, antioxidant enzyme activity might be efficient tool to identify autotetraploid in S. miltiorrhiza.…”