Ion leakage as an indicator of vigor in field bean seeds

This preliminary study was conducted to determine whether the physiological quality of field bean (Phaseolus vulgaris L.) seeds could be rapidly evaluated using the potassium leachate and the conductivity tests. Five seed lots of cultivar IAC-Carioca were tested for germination, accelerated aging (41 degrees C/72 h) and exposed to nine preconditioning periods (from 1 to 24 h) at 25 degrees C before conductivity readings. The potassium leakage was determined after six imbibition periods ranging from 15 to 90 min. Results confirmed previously reported information on the usefulness of the potassium leachate test as differences of physiological quality among seed lots were identified using the combination of 25 pure seeds imbibed in 75 ml distilled water at 30 degrees C for 30 or 45 min. The possibility of shortening the imbibition period (up to 12h) for field bean seeds conductivity test was also determined.