Abstract

Author:
Uko, I., Amadioha, A.C., and Ekeleme, F.

Doi: 10.26480/trab.01.2025.07.12

This is an open access article distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

Evaluation of the combined effect of crop spacing, cassava variety and different weed control methods on the density of M. invisa in cassava field was conducted at Umudike, Southeastern Nigeria during 2015 and 2016 cropping seasons. The study was laid out in split-split plot in randomized complete block design with three replications. The main plot treatments consisted of three crop spacing (1 m × 0.6 m, 1 m × 0.8 m, and 1 m x 1 m). The sub-plot treatments included two cassava varieties of contrasting morphology (TME 419 and NR 8082) while the sub-sub-plot treatments were four weed control methods (W1 – hoe weeding at 4, 8 and 12 weeks after planting), (W2 – S-metolachlor (1160 g/ha) + atrazine (1480 g/ha) applied pre-emergence followed by hoe weeding at 12 and 16 WAP), (W3 – S-metolachlor (1160 g/ha) + atrazine (1480 g/ha) applied pre-emergence followed by trifloxysulfuron sodium (8 g/ha) applied post-emergence at 8 WAP) and (W0 – Weedy checks). Data collected were subjected to analysis of variance (ANOVA). Significant means were separated using least significant difference – LSD. The results obtained showed that M. invisa density was significantly low in the three weed control methods used. NR 8082 cassava variety reduced the level of emergence and density of M. invisa whereas the TME 419 which is a non-profuse branching variety did not significantly reduce the population of the weed. Furthermore, plant spacing had no significant effect on the M. invisa density in both cropping seasons.