The Defense Response Involved in Sweetpotato Resistance to Root-Knot Nematode Meloidogyne incognita: Comparison of Root Transcriptomes of Resistant and Susceptible Sweetpotato Cultivars With Respect to Induced and Constitutive Defense Responses

Abstract

Sweetpotato (Ipomoea batatas [L.] Lam) is an economically important, nutrient- and pigment-rich root vegetable used as both food and feed. Root-knot nematode (RKN), Meloidogyne incognita, causes major yield losses in sweetpotato and other crops worldwide. The identification of genes and mechanisms responsible for resistance to RKN will facilitate the development of RKN resistant cultivars not only in sweetpotato but also in other crops. In this study, we performed RNA-seq analysis of RKN resistant cultivars (RCs; Danjami, Pungwonmi and Juhwangmi) and susceptible cultivars (SCs; Dahomi, Shinhwangmi and Yulmi) of sweetpotato infected with M. incognita to examine the induced and constitutive defense response-related transcriptional changes. During induced defense, genes related to defense and secondary metabolites were induced in SCs, whereas those related to receptor protein kinase signaling and protein phosphorylation were induced in RCs. In the uninfected control, genes involved in proteolysis and biotic stimuli showed differential expression levels between RCs and SCs during constitutive defense. Additionally, genes related to redox regulation, lipid and cell wall metabolism, protease inhibitor and proteases were putatively identified as RKN defense-related genes. The root transcriptome of SCs was also analyzed under uninfected conditions, and several potential candidate genes were identified. Overall, our data provide key insights into the transcriptional changes in sweetpotato genes that occur during induced and constitutive defense responses against RKN infection.

Integrated Omic Approaches Reveal Molecular Mechanisms of Tolerance during Soybean and Meloidogyne incognita Interactions

“…Among these, the Ca 2+ pathway, phytohormones, and protein kinases are the core of responses in resistant cultivars. A decreased gall formation and size rate were typically related to these responses [ 173 , 174 , 175 , 176 ]. Interestingly, in our work, tolerant soybean seems to trigger responses independent of the action of phytohormones.…”

Identification of the Complex Interplay Between Nematode-Related lncRNAs and Their Target Genes in Glycine max L.

“…Additionally, the probable involvement of the endogenous SA has been remarked in Mi-1-mediated defense responses and in lesion formation in sites directly exposed to root-knot nematode (RKN) invasion (Molinari and Loffredo, 2006). Likewise, the functional annotation of DEGs in sweet potato (Lee et al, 2021) and in cotton (Kumar et al, 2019) demonstrated "response to salicylic acid" as the key enriched BP against nematode infestation. The role of JA, as another plant signaling compound, has been investigated upon nematode infection in different plant species (Hamamouch et al, 2011;Fan et al, 2015;Regis, 2015;Singh et al, 2020).…”

Comparative Transcriptome Analysis between Two Potato Cultivars in Tuber Induction to Reveal Associated Genes with Anthocyanin Accumulation

“…DEG (differentially expressed genes) analysis was performed according to ref. [ 63 ] using Ensembl potato database annotation [ 63 , 64 , 65 , 66 ].…”