Embryo and Seedling Survival and Plant Development

Abstract

Osborne and Boubriak (1994) defined five stages during seed development, maturation, the post-maturation period and dehydration. These are two stages of intolerance to desiccation and three stages of desiccation tolerance. When the seed moisture content is reduced to below 10%, seeds become drought-tolerant, as also do seeds that are rehydrated to about 35% moisture content. When the seed moisture content is between 10 to 35%, the dormant seeds of certain plant species can be dehydrated and rehydrated many times without apparent harm (Villiers and Edgcumbe 1975). In Avena sativa cv. Harmon (Poaceae), the longer the time of the initial imbibition period, up to 24 h, before desiccation to 10–12% moisture content, the shorter is the time of maximum germination following a desiccation period from 32 to 8 h. However, the total hydration time taken to complete germination, including initial and post-desiccation dehydration, was similar in all the treatments and in the range of 31-35 h (Bewley and Black 1982).