Field evaluation of the allelopathic effect of cassava (Manihot esculenta Crantz) against cogon grass (Imperata cylindrica Linn.)

Abstract

This study was conducted at the Experimental Area of CAPSU Burias Campus from March 24 to November 24, 2018, to evaluate the allelopathic effect of cassava against cogon grass at different planting densities. Three treatments were tested namely: Treatment A– 10,000 plants ha-1, Treatment B – 13,333 plants ha-1, and Treatment C – 20,000 plants ha-1. These treatments were arranged in a Randomized Complete Block Design and replicated three times. The data gathered for cassava were plant height, number of leaves, stem girth, biomass, number of tubers per plant, tuber length, tuber diameter, tuber weight, and tuber yield. For cogon, data collected included plant height, shoot weight, rhizomes weight and rhizomes length. Allelophatic effect was assessed as the mortality rate of cogon. Results of the study revealed that the biomass, number of tubers per plant, and tuber yield were significantly affected by the planting density of cassava. Plant height, stem girth, number of leaves, tuber length, tuber diameter and tuber weight were not significantly affected by the planting density of cassava. All growth parameters of cogon were comparable regardless of the planting density of cassava. Mortality rate of cogon was not also affected by the different planting densities of cassava.