The Effects of Pre-germination Treatments on Seed Germination and Growth of Wild Guavas in the Kingdom of Eswatini, Southern Africa

Dormancy is a condition where seeds will not germinate even when the environmental conditions (water, temperature and aeration) are permissive for germination. Wild guavas (Psidium guajava L.) are very popular in all agro-ecological zones of Eswatini. Farmers have shown an interest towards guava cultivation but have to cope with the shortage of quality propagation material. The demand is not fulfilled because of unavailability of superior seedling rootstocks, which might be due to poor seed germination and seedling growth. Nevertheless, it has been reported that guava seeds exhibited seed dormancy, which affects their growth and development. The experiment was carried out to study effects of different pre-germination methods on seed germination of guava. The study was conducted at the University of Eswatini, Luyengo Campus. The objective of the study was to get maximum germination of guava seeds in as short a time as possible. Four methods were used i.e., soaking in distilled water for five days at room temperature, soaking in hot water at 80ºC for three minutes, subjecting seeds to heat at 80ºC in oven for six minutes and soaking in 20% dilute sulphuric acid for three minutes. All these treatments significantly decreased days to germination of seeds compared with the control. Among the methods, treatment of guava seeds with 20% dilute sulphuric acid for three minutes was judged best with maximum germination percentage (93.3%); lowest germination mean time was observed in seeds soaked in distilled water (31 days). Highest plant height (44 mm) and highest stem girth of (3.37 mm) were recorded from seeds soaked in sulphuric acid after 150 days of sowing. Seeds without any pre-germination treatment showed poor germination (26.7%). On the basis of the findings, it can be recommended that propagators use sulphuric acid in seed priming for higher germination, growth and development.