Genetic variability and selection of natural populations of Campomanesia adamantium using REML/BLUP mixed models

The Brazilian Cerrado, a biodiversity hotspot, has been significantly impacted by climate change, land use modifications, and unsustainable extractivism, threatening the genetic diversity of many native species. Campomanesia adamantium (Cambess.) O. Berg, known as guavira, is a socioeconomically important fruit species in the Central-West region of Brazil. Given the current and potential value of guavira, alongside climate change, agricultural expansion in the Cerrado and inadequate extractivism, studies are necessary to understand and preserve natural populations and select genotypes for guavira breeding programs. The objectives of this study are to evaluate the morphophysiological traits of the fruits, estimate genetic parameters and genotypic values, and identify superior genotypes in natural guavira populations using mixed models (REML/BLUP). We analyzed 360 genotypes from six natural populations in Jardim and Bonito, MS, Brazil. The fruits were assessed for longitudinal and transversal diameters; fruit, pulp, and seed masses; peel thickness and total soluble solids. Significant genetic variability was detected for transverse diameter, fruit mass, and peel thickness, with heritability estimates ranging from low (0.03 for total soluble solids) to moderate (0.57 for peel thickness). Population structure influenced genetic variance, with populations 3 and 5 contributing the highest number of superior individuals. Genotypes 144, 145, 174, and 176 stood out for the largest number of characters shared traits related to the transverse diameter, fruit mass, and peel thickness, by comparing and identifying relationships between sets of genotypes. The study revealed that environmental factors significantly affect genetic variability, highlighting the importance of targeted selection strategies. Our findings provide valuable insights for conservation and genetic improvement programs for C. adamantium, ensuring the sustainability and economic potential of this native Cerrado species.