SELECTION OF PEACH GENOTYPES WITH LOW CHILLING REQUIREMENTS VIA MIXED MODELS

Abstract

A good selection of genotypes that show proper stability and adaptability in the characters of interest is crucial to obtaining elite cultivars. In this way, the objective of this work was to study, via mixed models, the performance of advanced selections of peach trees with low chilling requirements. Sixteen advanced peach selections from the EPAGRI Drupaceae breeding program were evaluated during three crops (2017, 2018, and 2019) and at two sites with different altitudes (220 m and 360 m). The characters evaluated were: yield (t.ha-1), maturation cycle (days), average fruit mass (g), soluble solids (°BRIX), and titratable acidity (%). They were analyzed via mixed models that use variance estimates obtained by the REML method (restricted maximum likelihood) by the SELEGEN – REML/BLUP program. Several genotypes showed good performance for the assessed characteristics, where sel. 0574 stood out as it obtained a good yield, high sugar content, and a good sugar/acidity ratio. Selections 0184, 0574, 0374, and 0791 present better performances for fruit yield, such as stability and adaptability (HMGV, RPGN, and HMRPGN). For the traits yield and average fruit mass, the effects of the environment do not change the behavior of the selections, making the genotypes representative of the region of interest.