Transcriptome analysis in osmo-primed tomato seeds with enhanced longevity by heat shock treatment

Thiago Barbosa Batista; Geysson Javier Fernandez; Tiago Alexandre da Silva; Júlio Maia; Edvaldo Aparecido Amaral da Silva

doi:10.1093/aobpla/plaa041

Transcriptome analysis in osmo-primed tomato seeds with enhanced longevity by heat shock treatment

AoB Plants. 2020 Aug 19;12(5):plaa041. doi: 10.1093/aobpla/plaa041. eCollection 2020 Oct.

Authors

Thiago Barbosa Batista¹, Geysson Javier Fernandez², Tiago Alexandre da Silva¹, Júlio Maia¹, Edvaldo Aparecido Amaral da Silva¹

Affiliations

¹ Department of Plant Production, Sao Paulo State University (UNESP), Botucatu, Sao Paulo, Brazil.
² Institute of Biology, Antioquia University, Medellín, Antioquia, Colombia.

Abstract

Seed priming is widely used in commercial seeds and its main function is to accelerate and synchronize seed germination. Undesirably, primed seeds show reduced longevity and treatments like heat shock have been shown to improve longevity in primed seeds. Nonetheless, the effect of heat shock treatment on primed seeds at the mRNA level is not known. Thus, the aim of this work was to investigate the effect of heat shock treatment on the longevity of primed tomato (Solanum lycopersicum) seeds at the physiological and transcriptome levels. Tomato seeds were primed and dried (control). Alternatively, primed seeds were subjected to heat shock treatment (38 °C/32 % relative humidity) before drying. Germination, vigor and longevity were evaluated. Transcriptome analysis was performed by RNA sequencing (RNA-seq) from biological samples collected immediately after priming and another samples collected from primed seeds followed by the heat shock treatments. The gene expression was validated by quantitative real time PCR (RT-qPCR). We showed that applying heat shock treatment after priming increased germination speed, enhanced seed longevity and preserved the vigor during storage of primed tomato seeds. Through transcriptome analysis, 368 differentially expressed genes were identified, from which 298 genes were up-regulated and 70 were down-regulated. We showed the increase of mRNA levels of HEAT SHOCK FACTOR-like and HEAT SHOCK PROTEIN-like chaperone genes, suggesting the involvement of the proteins coded by these transcripts in the enhancement of longevity in primed tomato seeds. The heat shock treatment after priming enhances and preserves the vigor of tomato primed seeds during storage. In addition, improves seed longevity through the increase in the expression of transcripts related to protection by response to stress.

Keywords: Chaperone molecules; Solanum lycopersicum L; improved longevity; primed seed; seed conservation; seed quality; storage.