Seed Cryostorage Enhances Subsequent Plant Productivity in the Forage Species Teramnus Labialis (L.F.) Spreng.

BACKGROUND: Teramnus labialis is an herbaceous legume that serves as a source of carbohydrates and proteins for animals and humans, and is valued for its nitrogen contribution to soil. The benefits of this species are, however, limited by low seed availability, small seed size and low in situ seed germination levels, due to physical dormancy. Cryostorage has been shown to be beneficial for both seed storage and breaking physical dormancy in seeds of various species. However, its potential effects on subsequent seedling emergence, plant growth and seed production need to be studied before large-scale implementation for T. labialis.

OBJECTIVE: To record agricultural traits of T. labialis after seed exposure to liquid nitrogen.

MATERIALS AND METHODS: Seeds were maintained at 5 degree C (control) or stored in LN before sowing. Seedling emergence percentage and traits related to plant growth and seed production were evaluated for 6 months.

RESULTS: Except for seed weight, all traits differed significantly between seedlings generated from cryostored and control seeds. Except for pod number, seedling emergence and plant growth traits were enhanced by cryostorage to a greater extent than seed production traits. Cryostorage resulted in cracks and breaks in the seed coat which were absent in control seeds (scanning electron microscopy), and in breaking physical dormancy may have facilitated more rapid seedling emergence than for control seeds.

CONCLUSION: Seed cryostorage enhances subsequent plant productivity in terms of growth and to a lesser extent seed production in Teramnus labialis, validating its use for commercial growth of this species.