ABSTRACT
Weed infestation of soyabean field causes 65% yield reduction in the forestsavanna
transition ecosystem of Nigeria. Single weed control method is often less
effective. However, Integrated Weed Management (IWM), will ensure more effective
and environment friendly control. There is little information on IWM application
on soyabean field. This study was therefore aimed at investigating response of
soyabean to IWM.
Field study was carried out in the 2008 and 2009 planting seasons to asses
the effectiveness of the integration of various weed control methods in the
production of soyabean (TGx 1414E) at Apapa village, Akinyele local government
area, Oyo state. The effects of Tillage (Tilled, Non-tilled), mulching (no mulch,
grass, plastic) and herbicides (no herbicides, metolachlor, pendimethalin) on
growth and yield of soyabean were assessed in a 2x3x3 factorial experiment
arranged in randomized complete block design with four replications and at
0.05x0.6m spacing. Data were collected at 16 weeks after planting on weed
diversity and abundance using 0.25m2 quadrat. The Relative Importance Value
(RIV) of each weed was determined using standard procedures. Also ten soyabean
plants were assessed per plot for growth and yield parameters (biomass, height,
number of pods and grain yield). Data collected were analysed using descriptive
statistics and ANOVA at p=0.05.
The most abundant weed was Spilanthes sp., with RIV of 58.5%, followed by
Chromolaena odorata (L.) R.M. King and Robinson with RIV of 7.5%. The highest
weed biomass of 136.4±18.5g/m2 was obtained in nontilled/
pendimethalin/grass treatment, followed by non-tilled/plastic
(20.0±5.1g/m2) and tilled plastic (18.2±3.0g/m2) but lowest in nontilled/
pendimethelin/plastic (15.4±2.9g/m2). Tilled/metolachlor/plastic reduced
weed biomass yield by 97.5%, tilled/plastic by 97.2%, tilled/grass by 82.6%,
control by 72.7%. The plants grown in the control plot had a mean height of
82.0±5.4cm in 2008 and 71.6±3.3cm in 2009. The lowest height of 51.6±5.6cm
was recorded in 2008 in the non-tilled/metolachlor/grass treatment and was
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50.8±4.6cm in 2009 in the non-tilled/pendimethalin/grass treatment. Plants
grown in tilled/metolachlor/plastic had highest pod numbers of 52.4±10.5 in
2008 and 57.3±4.0 in 2009 in tilled/pendimethalin/plastic and the lowest value
of 19.0±12.6 in 2008 and 24±0.8 in 2009 in the non-tilled/pendimethalin/grass.
The highest grain yield of 3.9±0.3 tons/hectare (2008) and 3.7±0.9 tons/hectare
(2009) were recorded in the tilled/pendimethalin/plastic treatment while the
lowest value of 1.6±0.3 tons/hectare and 1.7±0.4 tons/hectare was recorded in
the non-tilled/pendimethalin/grass treatment in 2008 and 2009 respectively. The
treatments are significantly different with regards to weed biomass, and grain
yield of soyabean in the two years. However, all plastic combined treatments
were not significantly different.
The tilled/plastic treatment ensured best weed suppression and highest
grain yield. Adopting it as an integrated weed management alternative may
reduce the amount of herbicides and labour input better than other strategies.
Key words: Integrated weed management, Metolachlor, Pendimethalin,
Soyabean, Spilanthes.
OGUNJOBI, A (2021). Response Of Soyabean (Glycine Max (L.) Merill) To Integrated Weed Management In A Forest-Savanna Transition Ecosystem In Oyo State, Nigeria. Afribary. Retrieved from https://afribary.com/works/response-of-soyabean-glycine-max-l-merill-to-integrated-weed-management-in-a-forest-savanna-transition-ecosystem-in-oyo-state-nigeria-2
OGUNJOBI, Adebare "Response Of Soyabean (Glycine Max (L.) Merill) To Integrated Weed Management In A Forest-Savanna Transition Ecosystem In Oyo State, Nigeria" Afribary. Afribary, 11 Apr. 2021, https://afribary.com/works/response-of-soyabean-glycine-max-l-merill-to-integrated-weed-management-in-a-forest-savanna-transition-ecosystem-in-oyo-state-nigeria-2. Accessed 14 Oct. 2024.
OGUNJOBI, Adebare . "Response Of Soyabean (Glycine Max (L.) Merill) To Integrated Weed Management In A Forest-Savanna Transition Ecosystem In Oyo State, Nigeria". Afribary, Afribary, 11 Apr. 2021. Web. 14 Oct. 2024. < https://afribary.com/works/response-of-soyabean-glycine-max-l-merill-to-integrated-weed-management-in-a-forest-savanna-transition-ecosystem-in-oyo-state-nigeria-2 >.
OGUNJOBI, Adebare . "Response Of Soyabean (Glycine Max (L.) Merill) To Integrated Weed Management In A Forest-Savanna Transition Ecosystem In Oyo State, Nigeria" Afribary (2021). Accessed October 14, 2024. https://afribary.com/works/response-of-soyabean-glycine-max-l-merill-to-integrated-weed-management-in-a-forest-savanna-transition-ecosystem-in-oyo-state-nigeria-2