Interpreting Morphology and Yield Response of Okra (Abelmoschus esculentus) to Weed Variables Using Regression Analysis

Abstract

The cohabitation of weeds with crops may not always pose problems. Weeds are plant pests that negatively impact crop yield. However, it is essential to determine when pest status is reached in crops for weed management decisions in crop production. Field experiments were conducted during the rainy seasons of 2017 and 2018 at the research farm of the Institute of Agricultural Research and Training Ibadan (7o38' N 3o 84' E), located in the rainforest-savanna transition agroecology of southwestern Nigeria. The experiments consisted of nine weed management practices and a weedy check arranged in Randomised Complete Block Design with three replications. Weed density and weight, along with okra's morphological attributes such as the number of leaves, leaf area, plant height and stem girth, were recorded 9 weeks after sowing (WAS). At commercial maturity, unlignified okra pods were harvested from 9-12 WAS. Simple linear correlation and regression analysis between weed parameters and okra traits was performed. The result showed a negative relationship between weed growth and okra yield in both trials. The negative impact of weeds on some morphological traits of okra probably led to the reduction in okra yield. However, plant height and number of nodes did not significantly (P < 0.05) influence okra yield. Weeds attained pest status for okra at a weed density of about 14.17 plants/m2 with weed dry and fresh weights of 10.05 g/m2 and 54.86 g/m2 , respectively. Hence, weed management is necessary for okra production to reduce yield loss.