Advanced search
Start date
Betweenand


Methods to evaluate the quality of annatto seeds: viability and vigor

Full text
Author(s):
Roberta Leopoldo Ferreira
Total Authors: 1
Document type: Doctoral Thesis
Press: Piracicaba.
Institution: Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC)
Defense date:
Examining board members:
Ana Dionisia da Luz Coelho Novembre; Claudio José Barbedo; José Laercio Favarin; Jose Otavio Machado Menten; Fernando Augusto de Oliveira e Silveira
Advisor: Ana Dionisia da Luz Coelho Novembre
Abstract

The multiplication of annatto plant has limitations due to the limited knowledge of the morphological and physiological characteristics of seeds and seedlings and restricted methods to determine the quality of the seed. The objective of this research was to study methods to determine the viability and vigor of annatto seeds (Bixa Orellana L.). Four seeds genetic access kept by the Agronomic Institute of Campinas, SP were used for research, analyzed in two stages: firstly, methods for testing the germination and tetrazolium and in the second, methods were evaluated to estimate the vigor, electrical conductivity, accelerated aging and cold and seedling length. The evaluation of seed quality was complemented by the determination of water content, germination test, the first count and seedling vigor classification, seedling development and the determination of bixin and seeds chemical composition. The appropriateness of the proposed methods to characterize the quality of annatto seeds was also verified by the progress of seed deterioration during storage for one year. The experimental design was completely randomized with four replications. The results were subjected to variance analysis and means were compared by the Tukey test at 5% probability. According to the results, regardless of the genetic access, the appropriate temperature range for annatto seeds germination is between 29,5°C and 31°C, and the paper substrate (between paper). To tetrazolium test the methods between paper or water immersion are appropriate to hydrate the seeds and the water content appropriate is 40%. The periods two hours, four hours or six hours are efficient to evaluate the seeds viability. The electrical conductivity test using 25 or 50 seeds, hydrated in 50 or 75 mL of distilled water, the temperature of 20°C and 25°C for eight hours, 16 hours or 24 hours, the accelerated aging with water and salt solution for 72 hours or 96 hours and the cold tests at temperatures of 15°C or 20°C for five or seven days are effective for classify the annatto seeds quality. (AU)

FAPESP's process: 10/12511-1 - METHODS TO EVALUATE THE QUALITY OF URUCUM SEEDS: VIABILITY AND VIGOR
Grantee:Roberta Leopoldo Ferreira
Support Opportunities: Scholarships in Brazil - Doctorate