Peach germplasm: Genetic diversity of low chill cultivars in Southeast Brazil

Author(s)

da Rocha Sobierajski, G. ; Blain, G. C.

• Document type: Journal article
• Source: Fruits; v. 77, n. 2, p. 10-pg., 2022-03-01.

Abstract

Introduction - The stone fruit breeding program of the Agronomic Institute (IAC) is greatly important for developing new fruit cultivars with high quality and low chill requirements. Germplasms should be well-characterized for estimating the genetic diversity, which is responsible for reducing crop vulnerability to both biotic and abiotic stresses, including those related to climate change. This study aims at evaluating the pomological diversity of IAC-Prunus germplasm to support the development of cultivars adapted to mild winters. Materials and methods - This study evaluated seven pomological qualitative and seven quantitative traits from 27 to 71 cultivars during three harvesting seasons. The qualitative traits were assessed by descriptive statistics and the quantitative traits by multivariate analysis and Principal Component Analysis (PCA). Results and discussion - The IAC-Prunus germplasm has 64 peach cultivars and 13 nectarine cultivars, of which 95.51% are used exclusively for fresh market. The results of the Pillai test and the analysis of variance indicated that all variables were significantly different among the cultivars in the three seasons. The first two components of the PCA explained most data variability: 83.46, 70.48 and 74.83% (2012-2014). The first component presents a contrast between ratio and pH versus titratable acidity whereas the second component presents contrast between fruit weight and pulp yield versus soluble solid. In general, the PCA validates the cluster formed by Euclidean distances. Conclusions - The IAC-Prunus germplasm exhibits high genetic diversity. The 'IAC Tropical 2' and 'IAC Colombina' were the most divergent cultivars. The cultivars were classified into four main clusters. (AU)

• FAPESP's process: 13/09450-9 - Breeding low-chill peaches (Prunus persica (L.) batsch and nectarines (P. persica var. nucipersica Dippel)
• Grantee: Graciela da Rocha Sobierajski
• Support Opportunities: Regular Research Grants