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Seeds with a chilling requirement were maintained fully imbibed at 22-25° C for more than 6 years without germination. Similar seeds stored air-dry at the same temperatures were dead by the second year. Cytological changes in the radicle meristem cells during the first year included the development of complex associations of ER with protein bodies. After 2 years imbibition, cytolysomes were formed, and by the fifth year membrane systems were extensively damaged. Upon release from dormancy, germination was delayed compared with that of normal, unaged embryos. During this delay, the vacuoles acted as lysosomes, engulfing and hydrolysing cytoplasmic organelles, Renewal was by sub-division of existing organelles, separating damaged from apparently normal zones by the formation of partition membranes. The relationship between lysosomal systems and the plant cell vacuole is discussed. The extended viability of imbibed seeds compared with dry seeds is discussed in relation to the possibilities of running repairs to membrane and genetic systems whilst the tissue is hydrated. [ABSTRACT FROM AUTHOR]

The article presents a study on the ordination of Plantago coronopus in the vegetation of dune slacks at Newborough Warren in Anglesey, Wales, using pattern analysis technique of P. Greg-Smith. It states that the scale pattern shown by Plantago coronopus was related to microtopography. Results also showed that its poor performance in the dune slacks is attributed to low nitrogen and phosphorous status. It mentions that germination is retarded in the dark and with gain in soil depth. Also, there is no effect in germination when the seeds are chilled and, though there is no germination in 50% sea water, the high salt content indicates no considerable injury to the seeds.

The article discusses research being done on the viability of seeds. It references several studies by M. L. Darsie et al and W. Crocker et al both published in the 1914 issue of "Botanical Gazette," by G. H. Shull in the 1914 issue of "Plant World," and H. Maxwell in the 1915 issue of "Nature." Crocker and colleagues investigated the seeds of Alisma plantago, dealing with the structure and microchemistry of the seed-coat, the water relations of the coat and embryo, the effect of acids on the rate of intake of water by the embryo, turgo inhibition and growth elongation of the embryo, elasticity of the seed-coat, and oxygen pressure in relation to germination of the seed and to chlorophyll formation in the seedling.

The article presents information on the genetic stocks stored at the U.S. National Seed Storage Laboratory. The Laboratory gives priority to seeds that are of economic importance. When stocks become depleted or there is a dangerous decline in viability, the National Seed Storage Laboratory has the responsibility for reincreases of the seed. It reports that the Laboratory has 52,000 accessions in storage including 112 tomato mutants, 310 barley lines, 400 radiation-induced mutants of oats, and 110 red pericarp lines of corn. Future geneticists can use a collection in the event of the death of the individual who had developed it.