Global Transcriptome Analysis and Identification of Differentially Expressed Genes in Strawberry after Preharvest Application of Benzothiadiazole and Chitosan

Abstract

The use of resistance inducers is a novel strategy to elicit defense responses in strawberry fruit to protect against preharvest and postharvest decay. However, the mechanisms behind the specific resistance inducers are not completely understood. Here, global transcriptional changes in strawberry fruit were investigated using RNA-Seq technology. Preharvest, benzothiadiazole (BTH) and chitosan were applied to the plant canopy, and the fruit were harvested at 6, 12, and 24 h post-treatment. Overall, 5,062 and 5,210 differentially expressed genes (fold change ≥ 2) were identified in these fruits under the BTH and chitosan treatments, respectively, as compared to the control expression. About 80% of these genes were differentially expressed by both elicitors. Comprehensive functional enrichment analysis highlighted different gene modulation over time for transcripts associated with photosynthesis and heat-shock proteins, according to elicitor. Up-regulation of genes associated with reprogramming of protein metabolism was observed in fruit treated with both elicitors, which led to increased storage proteins. Several genes associated with the plant immune system, hormone metabolism, systemic acquired resistance, and biotic and abiotic stresses were differentially expressed in treated versus untreated plants. The RNA-Seq output was confirmed using RT-qPCR for 12 selected genes. This study demonstrates that these two elicitors affect cell networks associated with plant defenses in different ways, and suggests a role for chloroplasts as the primary target in this modulation of the plant defense responses, which actively communicate these signals through changes in redox status. The genes identified in this study represent markers to better elucidate plant/pathogen/resistance-inducer interactions, and to plan novel sustainable disease management strategies.

Global transcriptome analysis and differentially expressed genes in grapevine after application of the yeast‐derived defense inducer cerevisane

“…Interestingly, CAB‐binding proteins are specifically induced in grapevine genotypes resistant to P. viticola following pathogen inoculation and this could explain the effectiveness of CER against this pathogen observed in our experiments. Moreover, genes encoding CAB‐binding proteins are induced by SA treatment in Arabidopsis and by chitosan and benzothiadiazole in strawberry . These findings corroborate the hypothesis of the existence of crosstalk between defense and other signaling pathways, such as that regulated by the phytochrome A/red light, leading to the induction of CAB genes .…”

Polymerization degree-dependent changes in the effects of in vitro chitosan treatments on photosynthetic pigment, protein, and dry matter contents of Ipomoea purpurea

“…Proteins also play a role in building intracellular structure and energy generating reactions, such as mitochondrial electron transport (28). In a recent report, chitosan application at 1% (w/v) concentration was shown to trigger reprogramming of protein metabolism with an increase of storage proteins in Fragaria × annanasa (29). In another report, Anusuya and Sathiyabama (30) found that chitosan treatment at 0.1% (w/v) increased protein con-tent in Curcuma longa cv.…”

Induced and primed defence responses of Fragaria vesca to Botrytis cinerea infection

“…However, no visible necroses was observed in F. vesca plants upon spray treatment of chemicals or the mock treatment. Also, there are reports of spray treating strawberry plants with different chemicals to study induced resistance (Terry and Joyce, 2000;Eikemo, Stensvand and Tronsmo, 2003;Hukkanen et al, 2007;Landi et al, 2017;Saavedra et al, 2017). We therefore consider the observed effects to be the plant's induced responses to priming agent treatments.…”