EXUDATE pH AND FLOODING TESTS TO EVALUATE THE PHYSIOLOGICAL QUALITY OF SOYBEAN SEEDS

FERNANDA BRITO CARDOSO,CARLOS HENRIQUE QUEIROZ REGO,ANA CARINA DA SILVA CÂNDIDO,JOSIANE VOGEL CORTINA THEODORO,CHARLINE ZARATIN ALVES

doi:10.1590/1983-21252018v31n315rc

FERNANDA BRITO CARDOSO, CARLOS HENRIQUE QUEIROZ REGO + Show 3 more

Open Access

https://doi.org/10.1590/1983-21252018v31n315rc

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Abstract

ABSTRACT The present study aimed to assess the variations in the parameters of the exudate pH and flooding tests to evaluate the physiological quality of soybean seeds. We subjected the lots of soybean seeds to germination, emergence, exudate pH, and flooding tests. Further, water content of the seeds, first count of germination, and emergence speed index were also determined. The exudate pH test studied the variations in the soaking period and temperature, while the flooding test assessed the variations in the amount of water and temperature at different periods of immersion. The experiment design was completely randomized. The results were presented as means and were compared using the Scott-Knott test at 5% probability. The Pearson’s correlation coefficient between the exudate pH and emergence of seedlings, and also between the flooding test result and emergence of seedlings were calculated. The results of the study indicated that the exudate pH test can be used to evaluate the physiological quality of soybean seeds after 30 min of imbibition at 20 °C. Further, the flooding test was efficient in evaluating the vigor of soybean seeds after 4 h of immersion either in 50 mL of distilled water at 25 °C or in 75 mL of distilled water at 30 °C.

Highlights

The speed at which trustworthy results are obtained is one of the important factors considered while evaluating seed quality
No variation greater than 2% in the water content between lots was observed in the present study. In tests, such as exudate pH and flooding tests, that expose seeds to hydration, seed samples with sharp variation in the water content are not recommended since dried seeds are subject to further deterioration during the tests
The results revealed that the exudate pH test was not efficient in the segregation of seed lots based on their physiological quality

Summary

INTRODUCTION

The speed at which trustworthy results are obtained is one of the important factors considered while evaluating seed quality. Despite the differences in their techniques, vigor tests, in general, are intended to detect significant variations in the physiological qualities of marketable lots of seeds. The exudate pH test can be applied and the results obtained are at a faster rate It avoids the use and/or unnecessary storage of seed lots with lower vigor (RAMOS et al, 2012). There is a need for standardization of such tests to evaluate the quality of seed lots in a simpler way In this milieu, the present study was conducted to assess the variations in the parameters of the exudate pH and flooding tests and the combinations of these parameters to differentiate lots of soybean seeds with different levels of vigor

MATERIAL AND METHODS

RESULTS AND DISCUSSION

CONCLUSIONS