EFFECT OF SEED EXTRACTION METHODS AND SEED STORAGE CONDITIONS ON THE QUALITY OF GARDEN EGG (Solanum aethiopicum) SEEDS
ABSTRACT:
Garden egg (Solanum aethiopicum) although listed as one of the neglected and underutilized species (NUS) worldwide is the third most consumed vegetable in Ghana. Seed for cultivation as such is obtained mainly from the informal seed sector in Ghana. Experiments were conducted at the University of Ghana with the objective ascertaining the influence of extraction methods, packaging bags and storage conditions on the quality of Legon1 garden egg seeds. For the first study fruits harvested at ripe red were subjected to two extraction methods namely; wet method extraction and 24, 48 and 72 hour fermentations. Quality parameters comprising of germination percentage, seedling vigour, purity, 100- seed weight and the presence of Exserohilum rostratum, Fusarium moniliforme, Fusarim oxysporum and Alternaria spp were measured. Seeds extracted with wet method extraction, 24 and 48 hour fermentations recorded relatively better performance in the parameters mentioned above compared to the 72 hour fermentation treatment. The second study evaluated the effect of seed extraction methods, three packaging materials and two storage conditions laid in a factorial 4x3x3x2 in a CRD replicated four times and analyzed using GenStat (2012 edition). Data were collected at the Ghana Seed Inspection Division. After 90 days of storage, wet method extraction, 24 and 48 hour fermentations stored for 30 to 60 days under refrigeration (5-8˚C) provided relatively higher germination percentage, seedling vigour, seedling biomas over 72 hour treatment fermentation. These treatments accumulated less moisture resulting in lower presence of Curvularia spp Fusarium moniliforme and Aspergillus flavus. Packaging material however, did not affect the quality of the seeds after storage. Significant interaction effects were recorded among the different treatment combinations. Seeds from the wet extraction stored for 30 to 60 days under refrigeration gave the overall best seed quality. Findings from the study indicate that the use of wet extraction method in seed processing and the adoption of storage at a temperature of 8˚C or less could maintain garden egg seed quality over a 60 day period facilitating availability of quality seed for the informal seed sector.