Canadian Journal of Pure & Applied Sciences

Abstract: Field experiments were conducted at the research farm of the College of Agriculture Lafia in the Southern guinea savanna agro ecological zone of Nigeria (080 30/N and 080 30/E, 18m above sea level) during the rainy seasons 2006 and 2007 to study the effects of nitrogen (0, 2.5 and 5.0 kg ha-1) and poultry manure rates (0, 2.5 and 5.0t ha-1) on the growth and calyx yield of roselle (Hibiscus sabdariffa L.). The nine treatment combinations were laid out in a randomized complete block design with three replications. Plant height, number of leaves per plant, number of branches per plant and total dry matter per plant were all significantly increased by both nitrogen and poultry manure application up to 120 kg N ha-1 and 5 t ha-1 respectively. Number of days to 50 percent flowering was neither affected by nitrogen nor does poultry manure application. Significant increase in the number of calyx per plant, calyx yield per plant and dry calyx yield per hectare were obtained by the application of 60 kg N ha-1 and 2.5 t ha-1 of nitrogen and poultry manure respectively. 60 kg N ha-1 and 2.5 t ha-1 therefore seemed to be the ideal nitrogen and poultry manure rates for the yield and yield attributes of roselle while 120kg N/ha and 5.0t/ha for vegetative growth in the Southern Guinea Savanna of Nigeria.