Seed storage conditions influence germination of Moringa oleifera Lam. seed

Moringa oleifera seed is used as a food/fodder source, for oil extraction, water purification as well as for the treatment of various ailments. The demand for high quality seed is therefore on the rise. Unfortunately, seed ageing is one of the main problems responsible for low quality seed. Finding appropriate storage conditions to ameliorate deterioration is therefore essential. Moringa seed viability has been investigated by several authors with inconsistent results due to climatic conditions and storage methods differing in each country. In previous experiments the seed moisture content was also not adjusted before seed storage. The aim of this study was therefore to investigate the effect of moisture content, storage condition and storage period on viability of M. oleifera seed grown in South Africa. Seeds were sampled from ripe fruit/pods, which were harvested from an 8-year-old established orchard at the Hatfield Experimental Farm of University of Pretoria in South Africa. The seeds were divided in two sub-lots. In the first sub-lot, treatments were arranged according to a three factorial scheme with four temperatures (-19, 4, 20 and 30 degrees C), three storage periods (6, 12 and 24 months), and two packaging (paper and aluminium) types. The second sub-lot was also arranged in three factorial schemes with four temperatures, three storage periods as mentioned above and three moisture contents (4, 8, 11%). At the end of each storage period, germination and viability (TTS) tests were performed on seed from each treatment combination according to ISTA methods. The behaviour of seed was evidently influenced by their moisture content and by their storage conditions. Moisture content above 8% influenced seed longevity negatively at 24 months of storage. Temperatures of -19 and 30 degrees C were not favourable for seed storage.