Breaking of Dormancy and Its Effects on Seedling Establishment of Date Palm (Phoenix Dactylifera L.)

Abstract

A study was carried out in the Botanical Garden of the Department of Plant Science and Technology, University of Jos, Nigeria, to determine the most effective method of breaking seed dormancy in Date palm (Phoenix dactylifera L.). The treatments comprised two types of seed (fresh; seeds less than six month old  and the dry seeds were more than six months old) with four different methods of breaking seed dormancy (seeds soaked in acid for 5 minutes, 5 minutes in boiling water, 24 hours in cold water and mechanical scarification) and the control (seeds were not treated). The experiment was laid out in a completely randomized design and each treatment was replicated five times. Germination rate (%) was measured weekly for four weeks and seedling height (cm) was measured at 2 weeks interval (beginning from 35 days after planting) for a period of eight weeks. The results showed that the different methods of breaking seed dormancy enhanced the germination of the Date palm and seedling growth. The boiling and cold water treatments had significantly (P<0.005) higher germination rate of 100% at 42 days after planting than the control which had 86.67%. The dry seeds had a significantly (P<0.05) low (26.67) germination rate at 35 days after planting but, did not differ significantly with the fresh seeds at 35 DAP. The boiling water treatment also had a significantly (P<0.005) high seedling height (25.00 cm) at 77 days after planting. The control had the lowest seedling height of 6.72 cm at 35 days after planting. The seeds treated with acids for 5 minutes, did not germinate at all. The result indicates that optimum germination and seedling establishment in Date palms occurred in fresh seeds and the most effective method of breaking the dormancy is through the use of boiling water.

Keywords: Date palm (Phoenix dactylifera L.) seeds, breaking dormancy and Seedling establishment