Abstract:
Integrated Nutrient Management with biochar and inorganic fertilizer is critical to sustainable
agriculture including the enhancement of production systems for climate change mitigation and
adaptation. The objective of this research was to evaluate how soil management could be improved
to respond to increasing environmental pressure on soil and crop in carrot production and to
examine how anthropogenic changes in and management of soil affect crop growth, yield and
nutritional quality. Mixed method approaches -sociological and field experimental research, were
employed in the study. In the sociological study, action research was conducted to explore farmers’
perceptions, production constraints and production output to inform the choice of treatment for
two field experimental studies conducted in 2016 and 2017 at the Multipurpose Crop Nursery of
the College of Agriculture Education, University of Education, Winneba, Mampong Campus. The
sociological study made use of cross-sectional, focus group discussion and stakeholder
engagements. Respondents in the cross-sectional study were randomly sampled while those of
focus group and stakeholder engagements were purposively sampled. The cross-sectional study
engaged 25 carrot growers in Asante Mampong Municipality. The field experimental study was a
3 x 5 factorial arranged in Randomized Complete Block Design (RCBD) and replicated three
times. Three levels of biochar at rates 0 ton/ha, 5 ton/ha and 10 ton/ha and 5 levels of inorganic
fertilizer (NPK 15:15:15 at 200 kg/ha; P&K 50:50 at 50 kg/ha; P&K 50:100 at 50 kg/ha; D.I. Grow
Liquid Fertilizer at 1L D.I. Grow: 200 L Water/ha; and No fertilizer) were used. The results
showed that avocado biochar could be used to amend and improve soil density, porosity and
moisture content and carbon stock to improve farmers’ capacity to adapt to environmental stresses
and to mitigate climate change. Biochar integration with inorganic fertilizers also proved to
significantly and variably affect soil physicochemical properties, crop growth, yield, yield
components and nutritional quality.
University of Education, Winneba http://ir.uew.edu.gh
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In view of the varied market preferences of tuber quality, it is recommended for farmers to manage
soils, crops and weather to specifically suite consumers and market preferences. It is recommended
that farmers apply 10ton/ha biochar with P&K 50:50 at 50 kg/ha for improved water holding
capacity, organic carbon composition and pH. It is also strongly recommended that during the
minor and major cropping season farmers respectively apply NPK 200kg/h + 5 ton/ha biochar and
P&K 50:100 at 50 kg/ha without biochar for best marketable yield. In terms of root diameter, 5
ton/ha biochar without fertilizer is recommended for soils with average soil nutrients during the
minor season. During the major season, it is recommended to apply P&K 50:100 at 50 kg/ha +10
ton/ha biochar for best root length. For best root diameter performance, it is recommended for
farmers to apply P&K 50:50 at 50 kg/ha without biochar during the minor cropping season and
P&K 50:50 at 50 kg/ha +10 ton/ha during the major season. For nutrition-informed carrot
production NPK 200 kg/ha+10 ton/ha biochar is recommended for high protein carrot during the
minor cropping season while major cropping season carrots should be produced with liquid
fertilizer+10 ton/ha biochar. For high carotenoid carrots, it is recommended to apply liquid
fertilizer+ 5 ton/ha biochar during the minor cropping season and NPK 200kg/ha +5 ton/ha biochar
applied during the major season. Correlation between soil properties, carrot growth, yield and
nutritional quality was also variable. There was significant effect of climate variability on carrot
growth, yield, and nutritional parameters.
Description:
THE SCHOOL OF RESEARCH AND GRADUATE STUDIES,
UNIVERSITY OF EDUCATION, WINNEBA IN PARTIAL FULFILMENT OF THE
REQUIREMENTS FOR THE AWARD OF
MASTER OF PHILOSOPHY (M.PHIL) IN AGRONOMY IN THE
UNIVERSITY OF EDUCATION, WINNEBA
MAY, 2019