Transcriptome dynamics of rooting zone and leaves during in vitro adventitious root formation in Eucalyptus nitens

AYALA, PAULA G.; ACEVEDO, RAÚL M.; DUARTE, MARÍA J.; LUNA, CLAUDIA V.; GONZALEZ, SERGIO A.; RIVAROLA, MAXIMO L.; MARCUCCI POLTRI, SUSANA N.; GONZALEZ, ANA M.; SANSBERRO, PEDRO A.

Corrientes

Congreso; XII Congreso Argentino de Bioinformática y Biología Computacional.; 2022

Asociación Argentina de Bioinformática y Biología Computacional - A2B2C

The properties of wood and the agronomic attributes associated with its fast-growing and tolerance to frost turn around Eucalyptus nitens as a valuable forest alternative. However, the rapid maturation-related decline of adventitious root (AR) formation limits the success of vegetative propagation of selected adult trees. In order to elucidate the molecular mechanisms involved in AR formation, we set out to analyze the variation in gene expression during the early stage of the AR induction phase of E. nitens microcuttings and its relationship with the loss of maturation-related decline of AR formation. Through histological techniques, the ontogenic phases that comprise the developmental process were delimited, and within the quantification of the scarecrow and shortroot genes, the appropriate developmental stage of sample collection for the massive sequencing (RNAseq) was established. The analysis of the variation in the transcriptomic profiles of leaves and stems made it possible to clarify the auxin metabolism that occurs in the propagule in response to IBA treatment. Likewise, it made it possible to interpret the hormonal interaction and the signaling process leading to the formation of the root meristem. The quantification of a group of genes involved in the morphogenic process confirmed that cytokinin signaling as negative regulators of the morphogenic process determines, in part, the decrease in rooting capacity as a function of age. The analysis of the transcriptomic variation in the leaves and stem base provided profuse information that allowed us: 1) to elucidate the metabolism of auxins, 2) to understand the hormonal interaction and the signaling process involved, and 3) to collect data associated with their recalcitrance.