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Quercus ilex L., an evergreen oak species typical of the western and central Mediterranean basin, is facing decline and dieback episodes due to the increase in the severity and frequency of heat waves and drought events. Studying xylogenesis (the wood formation process) is crucial for understanding how trees respond with their secondary growth to environmental conditions and stress events. This study aimed to characterize the wood formation dynamics of Quercus ilex and their relationship with the meteorological conditions in an area experiencing prolonged drought periods. Cambial activity and xylem cell production were monitored during the 2019 and 2020 growing seasons in a Q. ilex forest located at the Vesuvius National Park (southern Italy). The results highlighted the significant roles of temperature and solar radiation in stimulating xylogenesis. Indeed, the correlation tests revealed that temperature and solar radiation positively influenced growth and cell development, while precipitation had an inhibitory effect on secondary wall formation. The earlier cell maturation in 2020 compared to 2019 underscored the impact of global warming trends. Overall, the trees studied demonstrated good health, growth and adaptability to local environmental fluctuations. This research provides novel insights into the intra-annual growth dynamics of this key Mediterranean species and its adaptation strategies to climatic variability, which will be crucial for forest management in the context of climate change.

Objective: GRFs (growth-regulating factors) are transcription factors that significantly influence plant development and stress response. In the present study, genome-wide discovery and analysis of the CsGRF family and its significant roles in Camelina sativa development was done utilizing model GRF genes of Arabidopsis thaliana that are available in the public domain databases. Methods: Gene structure analysis, exon and intron structures, phylogenetic analysis, mapping of various GRF genes on the chromosome's distribution, conserved domain analysis, and synteny analysis will be systematically categorized. Investigation of cis-regulatory elements will also be carried out using various bioinformatic approaches. Results: In the C. sativa genome, 19 GRF gene members and 4 GRF variants were found using publicly available genomic data. The encoding regions of GRF1, GRF2, GRF2A, and GRF8 were similar and maximal, i.e., 2046 bp, which encodes 555 amino acids, followed by GRF2. C. sativa has the most GRF gene representatives, scattered throughout six chromosomes, and appears to have 3 to 4 protein-coding regions. GRF is involved in biological processes (44.7%), molecular activities (50%), and cellular functions (24.6%). The molecular weights of GRF proteins range from 29.57 to 61.57 kDa. The majority of GRF proteins have a theoretical PI between 7.0 and 9.42. All CsGRFs have preserved QLQ and WRC (Trp, Arg, Cys) domains. All C. sativa proteins have SNH and QG (Gln, Gly) domains. The motif composition and gene structure of CsGRFs from the same sub-group were similar. In the analysis of conserved domains, the motifs of CsGRF genes were highly conserved. According to synteny investigations, large-scale duplications played a significant role in expanding the CsGRF family. Conclusions: Our findings will help to understand the functions of the GRF family in the evolutionary and physiological aspects of C. sativa and provide a future direction for novel work to improve crop productivity. Identifying single-gene families in multiple plant species is best to enhance crop productivity, growth, and development.