Effect of varieties and weeding regimes on weed and performance of

Abstract

A Field trial was conducted at the aerobic rice experimental field of the National

Cereals Research Institute (NCRI), Badeggi, Nigeria (9

° 04 N and 6° 7 E)

in 2007 and 2008 wet seasons to determine the weed competitiveness and

performance of inter

†and intraâ€Âspecific aerobic rice (Oryza sativa L.) varieties

under seven weeding regimes. The trial was laid out in a split plot design

with the two varieties of rice (NERICA 1 as inter

â€Âspecific and FARO 46 as

intra

â€Âspecific) assigned to the main plot while seven weeding regimes (hoe

weeding at 25, 45, and 65 days after sowing (DAS), 25 DAS, 45 DAS, 25 and

45 DAS, application of 3’,3’

†dichloropropionanilide /2, 4 – Dichlorophenoxy

acetic acid (orizo plus

R) by Candel Company Ltd. at 3.5 kg active ingredient

(ai )ha

â€Â1 at 25 DAS, hoe weeding at 25 DAS followed by orizo plus at 3.5 kg ai

at 45 DAS and weedy check) constituted the sub – plots. The treatments

were replicated three times in a split plot design. From the results, interspecific

variety (NERICA1) had better weed suppression ability with higher

grain yield of 3.1 t ha

â€Â1 than the intraâ€Âspecific variety (FARO 46). Weed control

was better when hoe weeding was done at 25, 45 and 65 DAS or 25 and

45 DAS and at 25 DAS followed by orizo plus at 45 DAS than in other treatments.

However, hoe weeding at 25, 45 and 65 DAS gave significantly

greater grain yield than other treatments. Although economic yield was obtained

from hoe weeding at 25 DAS followed by orizo plus at 45 DAS.