Analysis of Peach Germplasm in Mexico

Abstract

A wide range of peach [ Prunus persica (I,.) Batsch] germplasm was collected from the most important peach growing regions in Mexico and some Latin American countries, as well as from breeding programs in the United States, Europe, and South Africa. Budded trees, seedlings derived from selfing cultivars and selections, and seed samples from various growing regions were propagated and planted in central Mexico. Twenty eight morphological or phenological variables were recorded on 52 accessions representing different geographic regions. The highest degree of variability was observed for traits related to bud density and distribution, and to phenological variables associated with temperature requirements such as budbreak and harvest seasons, leaf fall, fruit development, and seed stratification period. Principal component analysis (PCA) integrated groups of phenotypes based mainly on growth habit, shoot diameter, bud and leaf size, as well as resistance to powdery mildew, rust, and frost. PCA provides support for the development of objectives and breeding strategies in the search for germplasm and cultivars for nontraditional peach growing regions.