Effects of Scarification and Dipping Duration on the Seedling Emergence and Growth of Golden Shower Tree (Cassia fistula LINN).

Abstract

A field experiment was carried out at the Horticultural nursery of Crop production department, Federal University of Technology, Minna, between April and August 2017. The aim of the research was to compare the effect of scarification and dipping duration on the seedling emergence and growth of Cassia fistula (Golden shower). Golden shower is a multipurpose plant widely used for its ornamental and environmental beautification but it has problem of hard seed coat dormancy which affect the rate, speed and percentage of germination, thus limit seedling production. Scarification method by using mechanical means and acid hold promise in breaking the dormancy of the seed of golden shower. Field trials were conducted to determine the best method of scarification and dipping duration for optimum germination and seedling growth using gibberellic acid and mechanical method at different dipping duration of 10, 20, and 30 minutes. In the experiment, a 2x4 factorial arrangement in a Complete Randomized design with five replicates, two factors (i) made up of scarification method by the use of gibberellic acid and by mechanical means (ii) dipping duration of 10, 20, and 30 minutes. and the use of one, two and three lines and untreated (control). Data collected on germination and seedling growth parameters, were subjected to Analysis of variance (ANOVA) using DMRT and means were separated using Least Significant Difference (LSD) at 5 % level of probability. In the experiment, highest germination percentage (77 %) was recorded in the seeds treated mechanically, followed by the seeds treated with GA, (60 %) and the untreated seeds had the least germination percentage (53 %). Also seeds dipped in GA, for 30 minutes had the highest percentage germination followed by 20 minutes dipped and seeds dipped for 10 minutes had the least while seeds with three lines had the highest (83 %) followed by the seeds with one line and the seeds with two lines had the least germination percentage. Data were also collected on plant height, number of leaves, leaf area, number of branches and stem girth. It is therefore, concluded that the highest germination and growth yield were recorded on seeds treated mechanically and the interaction effect showed that mechanical scarification using three lines improves the breaking of seed dormancy in Cassia fistula (golden shower) and it enhance mass propagation of the ornamental tree.