Field Performance of Cryopreserved Seed-derived Maize Plants.

BACKGROUND: Cryo-preservation of plant materials in liquid nitrogen (LN) has been described as a suitable technology to conserve genetic resources of several species. However, the potential effects of LN in the subsequent plant growth in the field should be studied before large-scale implementation of cryopreserved germplasm banks. OBJECTIVE: To describe the field performance of cryopreserved seed-derived maize adult plants. MATERIALS AND METHODS: Germination percentage and numbers of leaves and ears per plant, internodes in stems, middle - aged leaf length, plant height, ear traits and weight of 100 seeds were recorded. RESULTS: Statistically significant differences between adult plants derived from cryopreserved seeds and the control treatment were not observed (t-test, p=0.05). CONCLUSION: The results presented confirm at the phenotype level the effectiveness of maize seed cryostorage to preserve and regenerate true-to-type plants.

Biochemical characterization of ecuadorian wild Solanum lycopersicum Mill. plants produced from non-cryopreserved and cryopreserved seeds.

This paper presents some of the effects of cryopreservation of wild Solanum lycopersicum Mill. seeds on the early stages of germination post liquid nitrogen exposure. Percentage of germination, conversion into plantlets and plant fresh mass were evaluated after cryostorage. Levels of chlorophyll pigments (a, b, total), malondialdehyde, other aldehydes, phenolics (cell wall-linked, free, and total) and proteins were determined. Peroxidase and superoxide dismutase activities were recorded. Liquid nitrogen exposure increased the percentage of seed germination at 5 days but at 7 days, the conversion into plantlets and the plant fresh mass were not statistically different between non-cryopreserved and cryopreserved samples. Several significant effects of cryopreservation were recorded at the biochemical level at 7 days of germination under controlled conditions. Highly significant effects due to liquid nitrogen exposure were observed in leaves: increased levels of peroxidase enzymatic and specific activities and cell wall-linked phenolics. Very remarkable effects were also recorded in roots: decreased contents of chlorophylls and cell wall-linked phenolics.