Factors Affecting Seedling Growth Performance and Quality of Two A<i>cacia Species and Shinus Molle </i>on Nursery Stage, Southern Oromia, Ethiopia

Abstract

The study was carried out within the Nursery of the Department of Forestry, at Sinana Agricultural Research Center, on the effects of different soils media and varying pot sizes on the early growth of <i>Acacia abyssinica, Acacia saligna and Shinus molle </i>were investigated. Four different soils media used were forest soil (FS), compost (Co), sand soil (SS) and local soil (LS) in different pots size (PS1=8 cm=control, PS2=10 cm and PS3=12 cm lay flats) 15 cm in length and five growing media (GM) or soil mix proportion based on volume GM1= (2 part local/Top soil:2 part forest soil:1 part sand; GM2=2 part local soil:2 compost: 1 part sand; GM3=1 part local soil:2 part forest soil:2 part sand; GM4=3 part local soil:2 part compost:1 sand soil and GM5=3 local soil:2 forest soil:1 sand=control) were filled up of different types of soil named above, and quantified using weighing balance. The experiment was laid out in Randomized Complete Block Design (RCBD) at the Forestry nursery in the study area. The study involved the use of five (5) planting media and three different plastic pots in three (3) replicates. The parameters measured are plant height (cm), seedling root collar diameter (mm) and dry matter (shoot, root and root to shoot ratio). The data collected at the end of twenty weeks were subjected to Analysis of Variance (ANOVA) and means were separated using Duncan test showed that <i>Schinus molle, A.abyssinica </i>and<i> A.saligina</i> tree species plant and grown in large pot size (PS2) and growing media (GM3) had the highest performance with mean value of plant height 19.83cm, 7.833cm and 13.167cm and seedling root collar diameter in GM5PS3 (4.09mm), GM4PS3 (3.35mm) and GM4PS1 (3.97mm) respectively were high significantly (P< 0.05). It is therefore recommended that large pot size (PS3) and GM2 and GM3growing media be used for optimal production of all <i>Schinus molle, A.abyssinica </i>and<i> A.saligina </i>tree species seedling production at nursery stage and their plantation success. This study revealed that optimum ratio of compost and forest soil in growing media and relatively big container/pot size have favorable good quality of seedling growth for all studied tree species for all growth parameters. This is may be due to nutrient variation in the growing media which is farther needs investigation on growing media nutrients contents.