The volatile exudates from germinating pea seeds of different viability and vigor

Abstract

Pea seeds var. Kriter were stored aseptically at 92% relative humidity and 30 °C. After 0, 4, 6, 8, or 10 weeks of storage, viability, vigor, and volatile exudates were determined on sublots of seeds. As storage time increased, vigor, as measured by dehydrogenase activity, growth of embryonic axes, and conductivity decreased. Later, viability also decreased. Imbibing and germinating pea seeds produced ethanol, acetaldehyde, and lesser amounts of methanol. No qualitative differences in volatile exudates were observed from germinating seeds regardless of age or storage condition. Nonaged seeds with highest vigor produced the smallest amounts of volatiles, but with increased aging the quantities of ethanol and acetaldehyde gradually increased. Dry seed produced small quantities of both volatiles. The amount of these compounds produced reached a maximum between 12 and 48 h of germination. Infestation of seed samples with Enterobacter cloacae or Trichoderma harzianum reduced the quantities of these compounds measured. These results indicate that determinations of acetaldehyde and ethanol in the space over germinating seeds by means of gas chromatography may be a useful seed vigor test.