Prediction of groundnut (Arachis hypogaea L.) seed quality after ethanol vapor ageing based on seed respiration rate using non-dispersive infrared CO2 sensor

Abstract

Importance of the work: Conventional methods for evaluating groundnut seed quality are
time-consuming and often destructive. Real-time respiration measurement could provide a
rapid and non-destructive method for assessing seed viability and vigor.
Objectives: To generate groundnut seed lots with varying physiological quality through
ethanol vapor ageing, determine the relationship between seed quality and respiration rate,
and develop a real-time respiration rate measurement method for indicating seed viability and
vigor.
Materials and Methods: Groundnut seed lots with varying physiological quality were
generated by ethanol vapor ageing for 0 min, 10 min, 20 min, 30 min or 40 min. Seed viability
and vigor were assessed, and real-time respiration rates were measured for 24 hr using a nondispersive infrared CO2 sensor to determine their relationship with seed physiological quality.
Results: Ethanol vapor ageing progressively reduced seed quality, with germination
decreasing from 88.5% to 6.0%, tetrazolium viability from 84.0% to 26.0%, and electrical
conductivity increasing from 4.69 to 51.02 µS/cm/g as ageing duration increased from 0 min
to 40 min. Seed respiration rate was significantly and negatively correlated with physiological
quality over 24 hr, and the 3 hr measurement produced strong predictive relationships with
all quality parameters (R² > 0.80), including germination (R² = 0.88) and tetrazolium viability
(R² = 0.97), indicating its potential as a rapid, non-destructive test.
Main finding: Ethanol vapor ageing in a vacuum container effectively generated groungnut
seed lots with varying levels of physiological quality. Real-time respiration rate, particularly
after 3 hr, showed potential as a rapid and non-destructive indicator of seed viability and vigor.