Response of mango ginger (Curcuma amada) to plant population and different weed control methods in the forest-savanna transition zone of south-western Nigeria

Abstract

Field trials were conducted in the early cropping seasons of 2016 and 2017 at the Teaching and Research Farm of Federal University of Agriculture, Abeokuta (07? 20? N, 3? 23? E 159 m above sea level) in the forest-savanna transition zone of south-western Nigeria to evaluate the response of mango ginger to plant population and different weed control methods. Treatments were laid out in a randomized complete block design with a split-plot arrangement and replicated three times. The main plot consisted of two plant populations: 444,444 plants/ha and 250,000 plants/ha, while the sub-plots consisted of ten weed control methods. The collected data on growth and yield of mango ginger plant, and weed biomass were subjected to analysis of variance (ANOVA) and the means of the treatments were separated using the least significant difference (LSD at p ? 0.05). Planting mango ginger at 444,444 plants/ha resulted in a 43.1% increase in rhizome yield compared to 250,000 plants/ha. Different weed control methods gave significantly higher crop vigor score, yield and yield components than the weedy check. Relative to the highest value in both years, uncontrolled weed infestation resulted in a 91.4% reduction in rhizome yield. There was a 60.7% increase in mango ginger rhizome yield when post-emergence weed control followed pre-emergence weed control. Our study has revealed that mango ginger, as a perennial crop with initially slow growth, requires a weed-free period beyond the first 12 weeks after planting (WAP) for acceptable weed control and optimum rhizome yield. Hence, a pre-emergence application of oxyfluorfen at a dosage of 0.24 kg a.iha-1 and a post-emergence hoe weeding are recommended.