ABSTRACT

Seed germination rates, types and early seedling growth rates of some tropical plant species were studied at Umudike, Nigeria. A reconnaissance survey was carried out to know the location of each plant species. Each of the plant species was marked with a numbered plastic tag. The mature fruits that dropped from the trees were collected from the fruiting plant and processed manually. Seed viability test was conducted using the floatation method. Except the seed of Garcinia kola, a total of 400 viable seeds of each plant species were used for the germination test. Four germination boxes each measuring 50 x SO x 10 cm were used for each plant species. Cotton wool was used to fill the germination box to 5.0 cm level before the seed broadcast was made. Watering of the broadcast seeds was done every morning and evening. Germinated seeds were counted every week and recorded. Each seedling was picked and transplanted in a polythene bag filled with a mixture of top forest soil and poultry droppings at equal ratio. Five treatments were assigned to Garcinia kola seeds. A total of 400 viable seeds were initially soaked in a bucket filled with water. A total of 100 seeds were removed from the water after 24; 48; 72 and 168 hours and were broadcast in a separate germination box. Another 400 viable seeds were scarified and soaked in another bucket filled with water. A total of 100 seeds were X removed after 24; 48; 72; 168 hours and were broadcast in separate germination box. Another set of 400 viable seeds were kept in an oven set at a temperature of 70 °C. A total of 100 seeds were removed after 01; 02; 03; 04 hours and were broadcast. Another set of 400 viable seeds were chilled at a temperature of below 04 C. A total of 100 seeds were removed after 24; 48; 72; 168 hours and were broadcast. Another set of 400 viable seeds were kept at a temperature range of between 20 and 30 ®C. A total of 100 seeds were removed after 24; 48; 72; 168 hours and were broadcast. Watering was done once in two days. The broadcast seeds were observed for 300 days and the seeds that germinated after each 30 days were recorded. The seedlings were planted at the Department of Forestry and Environmental Management Nursery at espacement of 4.0 x 4.0 m. Measurement of the height growth of each of the seedlings was done every two weeks using a tape. It was observed that 11 plant species studied exhibited phanerocotylar epigeal foliaceous germination type, 14 exhibited phanerocotylar epigeal fleshy germination type, 7 exhibited phanerocotylar hypogeal germination type, 2 exhibited cryptocotylar epigeal germination type and 2 exhibited cryptocotylar hypogeal germination type. It was observed that Nauclea diderrichii seeds had exogenous dormancy while seeds of Garcinia kola had both endogenous and exogenous dormancy. Others had rapid germination type. The xi growth of tree species was affected by attacks on the apical shoot by larvae of insects. Only Pentaclethra macrophylla and Cola acuminata seedlings that were not affected by insect attacks. All the studied plant seedlings had periodical apical shoot growth more especially a week after rainfall.