Seleção genotípica de porta-enxertos na laranjeira 'Pera D-6 CNPMF' no cerrado amapaense

Abstract

Citrus cultivation in Amapá is an important additional option for family farming, generating value-added products, income, and employment. However, farmers in the region face challenges due to adverse edaphoclimatic conditions. To overcome these challenges, it is essential to develop and adopt orange scion/rootstock combinations adapted to improve fruit productivity and quality. In this context, research on rootstock performance in sweet orange trees faces environmental challenges, and to increase precision and efficiency in selecting these materials, advanced statistical models such as REML/BLUP are recommended. These models enable analyses of repeatability, stability, adaptability, and productivity. Thus, this study aimed to evaluate the productivity, adaptability, and stability of rootstocks combined with the 'Pera D-6 CNPMF' sweet orange under the edaphoclimatic conditions of the Amapá Cerrado. The experiment was conducted at the Cerrado Experimental Field of Embrapa Amapá in a randomized block design, consisting of 14 rootstock genotypes combined with the 'Pera D-6 CNPMF' sweet orange, with 4 replications and 5 plants per plot. Genetic and statistical analyses were performed using the SELEGEN software through the REML/BLUP method (restricted maximum likelihood/best linear unbiased predictor). The presence of genetic variability indicated the potential for selecting rootstock genotypes combined with the 'Pera' sweet orange. There was consistency in the ranking of selected genotypes for genetic gain, although the order was not identical. The rootstock genotypes 'Sunki Tropical' mandarin and BRS Matta provided higher genetic gains in the number of fruits (21.32%) and juice mass (33.87%), respectively. Superior genotype selection with accuracy above 70% can be achieved in seven evaluations, although for the number of fruits, 5 to 6 evaluations are sufficient, reducing costs and time. The rootstocks BRS Tabuleiro, 'Sunki Tropical' mandarin, BRS Bravo, 'Santa Cruz Cravo' lemon, and BRS N Gimenes Fernandes combined with the 'Pera' sweet orange showed simultaneously excellent results for stability, adaptability, and productivity, making them promising for cultivation under similar tested conditions.