Avaliações biométricas de caracteres agronômicos em progênies de pupunheira (Bactris gasipaes Kunth.)

Abstract

The pupunheira (Bactris gasipaes Kunth, Palmae) is one of the few domesticated palm trees, whose heart of palm and fruits stand out in the diet, especially in the Amazon region. However, there are no cultivars developed for fruit production, which are still targeted either for subsistence of riverine populations or for municipal markets, different from the cultivation for heart of palm which is a growing agribusiness. The fruits of the pupunheira have a great natural variability of colors, flavors, oiliness and texture. However, this variability also limits its market, since the fruits suitable for consumption in natura, production of flour or oil, have different characteristics. Therefore, given the importance of pupunheira cultivation for fruit production, the objective of this research is to direct strategies of genetic improvement for production of pupunha fruits from the evaluation of agronomic characteristics, using techniques and biometric models. The progeny test was conducted in the experimental field of Embrapa Rondônia, where families of half-siblings of pupunheira were arranged, distributed in one hectare. The experiment was designed in randomized blocks with 14 families arranged in three blocks with eight plants per parcel, spaced 6x4m apart. Agronomic characters were evaluated, as well as the components of the production, based on the evaluation of data of three agricultural years, which is equivalent to seven years of cultivation. The REML/BLUP method (maximum restricted likelihood/best linear unbiased prediction) was used to estimate the components of variance and genetic values. Improvements in the cultivation conditions provided by liming and fertilization were observed from 2012 (fourth year of cultivation) on the 0 to 20 cm layer. From the seventh year of cultivation the production of pupunha tends to stabilize genotypically. The number and weight of bunches are the main characters associated with fruit production. The selection gain with the estimates of the genotypic effects of the selected plants had a greater influence on the response of the traits with a genetic progress of 59,57% in the seventh year of cultivation, evidencing greater possibilities of gains with asexual propagation.