Physiological changes in the early stages of germination of pea seeds induced by aging and by infection by a storage fungus, Aspergillus ruber

Abstract

Pea seeds age rapidly and may be infected by storage fungi, e.g. Aspergillus ruber, when stored under conditions of high relative humidity and temperature (92% relative humidity and 30 °C in these experiments). In the absence of microorganisms, pea seeds retain their viability for 6 to 8 weeks, although the speed of germination is reduced. In embryonic axes, aging is associated with a slower increase in O2 uptake, a delay in protein synthesis, smaller ATP and amino acid pools, and reduced activity of alkaline phosphatase (EC 3.1.3.1) and 3-phosphoglyceraldelyde dehydrogenase (EC 1.2.1.12). Axes recover from these changes during germination. Infection by A. ruber reduces germination. In axes from infected peas the onset of protein synthesis is delayed even more and the ATP and amino acid pools are smaller than in aged axes. Axes from infected seeds recover slowly, if at all.