Genotype-environment interaction on the density of peach buds cultivated in a humid subtropical climate

Abstract

Abstract Studies on the interaction of genetic and environmental effects on floral morphogenesis in peach trees grown in humid subtropical climate provide important information related to adaptation and for assisting in the selection of new cultivars. This study aimed to verify the genetic and environmental effects and to identify peach tree genotypes with greater shoot length, vegetative bud, flower bud density adaptability and stability under humid subtropical climate conditions. Twelve peach tree genotypes were evaluated over a period of eight years, during the growing season (2006/07 to 2013/14) in Pato Branco-PR, Brazil. Data were collected for shoot length (SL), flower bud density (FBD) and vegetative bud density (VBD), as well as temperature, humidity and precipitation. For the analysis of adaptability and stability we used GEE Biplot methodology. SL was influenced by the temperature and relative humidity. Increased exposure time to temperatures below 20 °C and above 30 °C, high thermal amplitude and relative humidity of less than 50% reduced shoot growth. VBD and FBD were predominantly controlled by the genetic factor. For VBD, the genotypes ‘Cascata 1055’ and ‘Conserva 681’ were the most adapted. For FBD, the genotypes ‘Cascata 1055’, ‘BRS Bonão’, ‘Conserva 681’, ‘Cascata 967’ and ‘BRS Kampai’ presented better adaptability. The genotypes more adapted to the FBD can be recommended for cultivation in the humid subtropical climate, since they also present greater stability in the production of fruits, independently of the meteorological conditions that occur during the vegetative and reproductive season.