Changes in glass transition temperatures in germinating pea seeds
- 1 June 1995
- journal article
- research article
- Published by Cambridge University Press (CUP) in Seed Science Research
- Vol. 5 (2) , 117-120
- https://doi.org/10.1017/s0960258500002695
Abstract
An element of storage stability of many orthodox seeds is that the embryo cytoplasm is vitreous at normal storage temperatures. That is, as drying proceeds during seed maturation, intracellular solutions become so concentrated and viscous that diffusional movement is all but eliminated (Williams and Leopold, 1989). In this report the relationship between desiccation tolerance and the ability to form the vitreous state as germination proceeds is examined. As pea seeds (Pisum sativum cv. Alaska) imbibed water up to 18 h, no change in the glass transition temperature was seen, and the embryos remained desiccation-tolerant. Between 18 and 44 h of imbibition, the axes lost the ability to exhibit a distinguishable vitreous transition, and the embryos had lost the ability to survive desiccation. After about 50 h, embryos again showed vitrification but only at markedly lower temperatures, as would be expected to accompany the loss of oligosaccharides (sucrose, raffinose, stachyose and verbascose) and their replacement by monosaccharides during early germination (Koster and Leopold, 1988). Thus, the loss of desiccation tolerance during germination in pea seeds appears to be associated with a loss of the high temperature oligosaccharide: water glass and a subsequent appearance of a new glass transition at a lower temperature resulting from the accumulation of monosacchrides.Keywords
This publication has 14 references indexed in Scilit:
- Glassy State and Seed Storage Stability: A Viability Equation AnalysisAnnals of Botany, 1994
- Methods for Determination of Glass Transitions in SeedsAnnals of Botany, 1994
- The glassy state and accelerated aging of soybeansPhysiologia Plantarum, 1993
- Acquisition of desiccation tolerance in soybeansPhysiologia Plantarum, 1993
- Maturation Proteins and Sugars in Desiccation Tolerance of Developing Soybean SeedsPlant Physiology, 1992
- Water in Dry OrganismsPublished by Springer Nature ,1992
- Hydration, protons and onset of physiological activities in maize seedsPhysiologia Plantarum, 1991
- Beyond water activity: Recent advances based on an alternative approach to the assessment of food quality and safetyCritical Reviews in Food Science and Nutrition, 1991
- Localization and characterization of intracellular liquid-liquid phase separations in deeply frozen populus using electron microscopy, dynamic mechanical analysis and differential scanning calorimetryThermochimica Acta, 1989
- The Glassy State in Corn EmbryosPlant Physiology, 1989