Genetic parameters and characterization of the initial growth of Euterpe edulis.
Name: MARCELLO ZATTA PÉRES
Publication date: 25/02/2022
Advisor:
Name |
Role |
|---|---|
| RODRIGO SOBREIRA ALEXANDRE | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| MARCIA FLORES DA SILVA FERREIRA | External Examiner * |
| RODRIGO SOBREIRA ALEXANDRE | Advisor * |
| WAGNER BASTOS DOS SANTOS OLIVEIRA | External Examiner * |
Summary: Euterpe edulis Mart., popularly called juçara palm, is a species with an important ecological role in fruit production in the Atlantic Forest. The management of its fruits appears as a way to reduce the anthropic pressure caused by the search for its palm heart of high commercial value, since the species, with the cut of its stem, is unable to sprout. The objective of this study was to analyze the diversity of the species in the state of Espírito Santo and analyze its growth in the early stages, generating information for breeding studies and for seedling production. The fruits were collected in eight municipalities in the state at the point of fruit maturation. The variables of equatorial diameter (DEF), fresh fruit mass (MFF), fresh seed mass (MSS) was analyzed in the laboratory. The genomic DNA of 58 genotypes was extracted from samples of the cortex, with genotyping performed by eight species-specific codominant microsatellite markers. The emergence experiment was prepared in a completely randomized design (DIC), with four replications of 25 seeds of 68 genotypes, totaling 6800 seeds. At 153 days after sowing, the following were evaluated: percentage of emergence (E), emergence speed index (IVE), emergence rate (TME), seedling height (AP), and diameter at stem height (DAC). After these evaluations, approximately 3100 seedlings were transplanted into 280 cm³ tubes, with substrate: ¾ of Terra Nutri® + ¼ sand, and kept under 50% shade and irrigation five times a day for 12 minutes by micro sprinkler, for growth analysis. species start. In this period, analyzes were carried out at 50, 100, 150 and 262 days, of AP, DAC, shoot dry mass (MSPA), root dry mass (MSR), total dry mass (MST), Dickson quality index (IQD), with 558 seedlings in each evaluation period. On the 262nd day, the variable fluorescence/maximum fluorescence (Fv/Fm) in the largest leaf of each seedling was analyzed. The biometric characters of fruits and seeds (DEF, MFF, MFS) are the most efficient for distinguishing E. edulis genotypes, with the highest heritability values. Higher rg occurred among the biometric characters of fruits and seeds and among the growth parameters. The path analysis allowed us to observe the strong direct effect of the AFT variable on the IQD (0.775), as well as the strong indirect effect of the PA on the DAC (0.867). The Gompertz model proved to be effective in explaining the emergence behavior of the species, which presented rapid emergence in the first days, stabilizing the absolute emergence rate at 53 days. An average emergence of 45% was found, with matrices presenting values close to 100%. For all growth traits, low growth was observed until day 200, with a considerable increase until day 262 after transplanting. The results demonstrate a great variability among the individuals of the study population and the potential of the population to offer seeds for the propagation of seedlings.
Keywords: Euterpe edulis, emergence, genetic parameters, diversity, seedling quality.
