INFLUENCE OF INTER-ROW SPACING AND WEED CONTROL METHODS IN GROUNDNUT (Arachis hypogeal (L.)

Abstract

Weed competition has been identified as one of the major obstacles in crop production. The produc-
tion of groundnut is limited by high weed infestation resulting in yield losses ranging from 50 - 80% in
Nigeria. Hence, the need to evaluate integrated weed control in its production. Field trials were there-
fore conducted at the Teaching and Research Farm of the Federal University of Agriculture, Abeokuta
(7o 20’ N, 30
23’ E) to evaluate the influence of inter-row spacing and weed control methods on growth
and yield of groundnut during the wet seasons in 2009 and 2010. The experiment was a Randomised
Complete Design (RCBD) laid out in a split plot with three replications. The main plot treatment con-
sisted of three inter-row spacings of 60 cm, 75 cm and 90 cm while the subplots included five weed
control treatments of commercial formulation of metolachlor plus promethyne mixture (codal) at 1.0 kg
a.i/ha, codal at 1.0 kg a.i./ha followed by supplementary hoe weeding at 6 weeks after sowing (WAS),
codal at 2 kg a.i./ha, hoe weeding at 3, 6 and 9 WAS and a weedy check. Inter-row spacings of 60 cm
and 75 cm reduced weed growth with consequent higher yields compared to the inter-row spacings of
90 cm in the early season of 2009. Application of codal at 1.0 kg a.i./ha followed by supplementary
hoe weeding at 6 WAS combined with 60cm inter-row spacing gave effective weed control and
higher groundnut pod yield than hoe-weeded control in both years of experimentation.