Transcriptome analysis reveals the inhibitory nature of high nitrate during adventitious roots formation in the apple rootstock

Abstract

In the process of vegetative propagation of apple rootstocks, the development of adventitious roots (ARs) has crucial importance. Nitrate is an essential nutrient necessary for plant growth; however, the inhibitory effect of high nitrate on ARs formation has not been explored. The physiological and molecular mechanisms underlying ARs

Transcriptome Analysis Reveals Multiple Genes and Complex Hormonal-Mediated Interactions with PEG during Adventitious Root Formation in Apple

“…Furthermore, JA has been identified as a suppressive factor for the formation of ARs in Arabidopsis that acts downstream of the auxin pathway [39]. Comparable findings were also reported in apples, where increased JA accumulation at the stem basal sections of the apple rootstock prevents AR formation [17,20]. The concentration of JA-me and the expression of related genes were considerably higher in PEG-treated cuttings, showing that increased JA-me accumulation is detrimental for AR formation in GL-3 apple cuttings (Figures 5A,B and 7 and Table S6).…”

“…ABA is a stress-responsive hormone that is required for plant dormancy and stress tolerance. Several studies have revealed that ABA has a negative effect on root formation and development [17,18]. Compared with CK cuttings, PEG-treated cuttings hold significantly higher ABA content at all time points during the formation of ARs (Figure 5A).…”

“…It has been shown to promote tolerance to various abiotic stresses, including drought, salt, and low temperature. Increased endogenous ABA content has been reported to negatively regulate ARs and LRs in apples and other crops [17][18][19][20]. Furthermore, the accumulation of jasmonic acid (JA) at the stem basal parts of petunia cuttings hampers AR formation [21].…”

Identification of Genes Associated with Nitrogen Stress Responses in Apple Leaves

“…Recently, studies have targeted apple tissues to explore global N tolerance using RNA-seq analysis [22,23]; however, the detailed metabolic signals associated with N stress responses have not been investigated well. Our transcriptome data of apple leaves collected under contrasting N stress conditions provided valuable information about the expression dynamics of genes associated with each N-deficient/excessive stress response.…”

“…In apple orchards, proper N fertilization is a critical component of farmers' tree management, and during the growing season, the stress responses of apple trees induced by various N fertilization can result in unbalanced growth and physiological disorders. Global transcriptome data from previous studies [20,21] and recent studies have suggested examining the different responses to N tolerance in apple tissues [22,23]. However, little is known about the underlying molecular mechanisms of responsive metabolic signals associated with various N stress conditions in apple.…”