Pot size influence on the growth of eucalyptus species nursery seedlings

Different pot sizes are used to raise nursery seedlings and these determine the early growth rate of different species of seedlings. This experiment was set up to determine the best pot size for 2 eucalyptus species namely; E. saligna and E. grandis. The experiment was laid down as a Randomized Complete Block Design (RCBD) with 8 treatments replicated 3 times. Treatments comprised of four different pot sizes namely; large (9 by 20), medium (8 by 19), small (7 by 13) and smallest (6 by 10) cm respectively based on volumes, as well as the two eucalyptus species. The experiment was carried out for a period of 6 months during 2017 and 2018 in Egerton University tree nursery. One way ANOVA was performed on the measured variables using Genstat statistical package while the means were separated using Standard Error Deviation (SED) at P< 0.05. The results revealed that the large and medium pots showed significantly higher growth in shoot, root and foliage in most of the variables measured compared with small and the smallest pot sizes. Similarly, large and medium size pots showed almost similar response in most of the variables with little significant between them and similar trend was also repeated between the small and smallest pot sizes. On the other hand, both E. saligna and E. grandis showed similar growth in all the variables except in the number of branches whereby the former was significantly (P< 0.05) higher (8.69) compared with the latter (6.65). The larger pots contained a higher soil and water volume (1272 cm3) which supported better and healthy seedling growth as compared to the smaller pots whereby seedlings were stunted. This was shown by the latter being lower by 50% in shoot, root and total plant biomass compared with the former. It is therefore recommended to use medium sized pots to raise eucalyptus seedlings in the nursery since they are more economical and do not compromise the growth of seedlings.