Influence of Some Pregerminaton Treatments on Seed Germination and Seedling Quality of Two Ornamental Palm Species Common in Egypt I- Golden Cane Palm (Chrysalidocarpus lutescens H. Wendl)

Abstract

A pot experiment was conducted under shade at the nursery of Antoniades Botanical Garden, Hort. Res. Inst., Alexandria, Egypt during 2014 and 2015 seasons in order to overcome the hardseededness of golden cane palm (Chrysalidocarpus lutescens H. Wendl.) seeds by subjecting them after removing the fleshy exocarp to the following treatments: untreated depulped seeds (control), soaking in either tap or hot (60-70 °C) water for 48 h. under room temperature, scarifying the hard endosperm by either clefting it with a hacksaw or rasping it at the distal rounded end that facing the placental pointed-end with a file and soaking in concentrated H2SO4 (98.5 %) for either 1 or 2 h in a completely randomized design, replicated thrice, each replicate contained 10 seeds. The results have shown that soaking treatments either in tap or hot water for 48 h. gave the highest germination % (87.33 and 85.00 % in the first season and 90.00 and 87.50 % in the second one, respectively) compared to the control and other treatments in the two seasons. The least percent of germination was recorded by soaking in concentrated sulphuric acid for either 1 or 2 h., while the seeds treated with clefting or rasping treatments have failed to germinate in both seasons. The least no. days to either the highest percent of germination (G.V.) or 50 % germination (MGR) was also achieved by soaking either in tap or in hot water treatments. The means of germination rate index (GRI), vigour index (V.I.), seed viability (S.V.) and plumule length, as a real indicator for germination vigour, the lengths of seedling, sheath, leaf, petiole and root and No. leaves/seedling, as well as leaf content of chlorophyll a, b, carotenoids and total soluble sugars were also improved by the various treatments used in this study except the treatments of H2SO4 , but the excellence in most previous parameters was for soaking the depulped seeds in tap water treatment, which gave the utmost highest values at all in both seasons and followed by soaking in hot water one. Hence, it can be recommended to soak the depulped seeds of golden cane palm (Chrysalidocarpus lutescens H. Wendl.) in either tap or hot water for 48 h. in order to get the best germination characters and seedling quality.