Influence of storage conditions on seed germination and vigour of temperate forage species

An experiment was initiated in 1984 to compare the effectiveness of the new controlled environment seed store at the Institute of Grassland and Enviro nmental Research with the more conventional storage facilities of warehouse and fridge which have no control of temperature and/or humidity. The store was constructed for the medium-term storage of seed of forage species at a temperature of 2 degrees C and between 10 and 20% relative humidity. Seed of perennial ryegrass (Lolium perenne L.), Italian ryegrass (L. multiflorum Lam), hybrid rye grass (L. boucheanum Kunth.) and white clover (Trifolium repens L.) was stored in sealed jars, linen and plas tic bags and placed in each of the environments. Measurements of germination and seed moisture co ntent were made at the beginning of the experiment and at intervals during the ten year storage period. Seed vigour of the grasses was measured in 199 1. Species and cultivars tended to respond similarly during this storage pe riod. Germination of seed stored where there was no control of temperature and humidity (granary), declined rapidly compared to the fridge (control of temperature only; 4 degrees C) or the seedstore. Seed stored in the granar y also had the highest moisture content, which increased during storage, an d lowest vigour. Germination of seed stored in the fridge was similar to th at in the seedstore. Seed in the seedstore had a slightly lower moisture co ntent after ten years storage than when it entered the store. Linen bags we re the least effective method of storage for both grass and clover seed, pa rticularly in the warehouse type store, whilst for grasses the sealed polyt hene bag was the best method of storage. In the seedstore, the method of se ed storage was less important than in the other stores. The basis of the de cline in seed quality in the storage environments and containers is conside red and importance of correct storage conditions discussed.