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Discoveries in Agriculture and Food Sciences - Vol. 12, No. 4
Publication Date: August 25, 2024
DOI:10.14738/dafs.124.17181.
Omobowale, M. O., Kolayemi, O. R., Olenloa, A. E., Ogwumike, J. C., Ala, A. A., Omodara, M. A., Busari, G. S., Braimah, J. A., Ajao, S.
K., Otitodun, G. O., Nwaubani, S. I., Ileleji, K. E., McNeill, S. G., & Opit, G. P. (2024). Macro- and Micro-Climatic Influence on Maize
Quality and Insect Pest Management Strategies in Small Market Storehouses in Nigeria. Discoveries in Agriculture and Food Sciences,
12(4). 01-20.
Services for Science and Education – United Kingdom
Macro- and Micro-Climatic Influence on Maize Quality and Insect
Pest Management Strategies in Small Market Storehouses in
Nigeria
Mobolaji O. Omobowale
Department of Agricultural and Environmental Engineering,
University of Ibadan, Ibadan, Nigeria
Olumuyiwa R. Kolayemi
Department of Agricultural and Environmental Engineering,
University of Ibadan, Ibadan, Nigeria
Akhere E. Olenloa
Department of Agricultural and Environmental Engineering,
University of Ibadan, Ibadan, Nigeria
Jonathan C. Ogwumike
Department of Agricultural and Environmental Engineering,
University of Ibadan, Ibadan, Nigeria
Adeola A. Ala
Department of Zoology, University of Ibadan, Ibadan, Nigeria
Michael A. Omodara
Nigerian Stored Products Research Institute, Ilorin, Nigeria
Gbenga S. Busari
Department of Zoology, University of Ibadan, Ibadan, Nigeria
Jafar A. Braimah
Department of Zoology, University of Ibadan, Ibadan, Nigeria
Shekinat K. Ajao
Department of Zoology, University of Ibadan, Ibadan, Nigeria
Grace O. Otitodun
Nigerian Stored Products Research Institute, Ilorin, Nigeria
Samuel I. Nwaubani
Nigerian Stored Products Research Institute, Ilorin, Nigeria
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Discoveries in Agriculture and Food Sciences (DAFS) Vol 12, Issue 4, August- 2024
Services for Science and Education – United Kingdom
Klein E. Ileleji
Agricultural and Biological Engineering Department,
Purdue University, West Lafayette, Indiana, USA
Samuel G. McNeill
Biosystems and Agricultural Engineering Department,
University of Kentucky, Lexington, Kentucky, USA
George P. Opit
Department of Entomology and Plant Pathology,
Oklahoma State University, Stillwater, Oklahoma, USA
ABSTRACT
Weather plays a major role in the microclimate of grain storage facilities and could
impact the quality of stored grain, most especially in the humid tropics where
weather conditions are favorable to insect and mold formation. This study
compared the influence of macro and microclimates — temperature and relative
humidity (RH) in six storehouses located in three grain markets in Ibadan, Oyo, and
Ilorin, Nigeria. The study was conducted from February–December 2016.
Traditional Storage Practice (TSP) and Integrated Pest Management (IPM) were
used in each of the markets. The average size of each storehouse was 4 m × 2.5 m ×
2.5 m and each had twenty-five 100-kg polypropylene bags of maize stacked singly
(not nested) in five columns. 15 bags were randomly sampled monthly for moisture
content (MC) and insect counts using standard methods. Temperature and RH of the
ambient and in-between grain stack were recorded using data loggers. Mean
temperatures and RH for ambient, stack, and grain ranged from 29.3–30.80C and
53.9–59.4% for the storage period. Mean insect count for the six storehouses with
IPM and TSP were 1.4 and 7.6 in 700 g per bag, respectively. Ambient conditions
correlated with grain stack temperature in all storehouses. MC of stored maize was
not significantly affected by the location of storehouses and storage practices.
However, insect population was significantly affected by storage practices. Proper
grain storage management play a major role in maintaining grain quality during the
storage. Commercial grain aggregators are advised to adopt the IPM strategies and
ensure regular monitoring of the microclimates of bagged grain to reduce storage
losses.
Keywords: integrated pest management, insect infestation, losses, maize, microclimate,
moisture content
INTRODUCTION
Grains are regarded as the most important of all agricultural products stored by farmers and
aggregators in the tropics and sub-tropical regions of the world (Akowuah et al., 2015). Several
types of grain storage systems exist but the method of choice depends on several factors which
include the purpose of storage, the volume of grain involved, storage duration and available
resources (Okunade, 2013). In developing countries, poor and inadequate storage facilities
contribute to slow growth of agricultural development. It has been estimated that 25 to 33.3%
of the global grain crop is lost yearly during storage (Ibrahim, 2015). Traditional storage
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Omobowale, M. O., Kolayemi, O. R., Olenloa, A. E., Ogwumike, J. C., Ala, A. A., Omodara, M. A., Busari, G. S., Braimah, J. A., Ajao, S. K., Otitodun, G.
O., Nwaubani, S. I., Ileleji, K. E., McNeill, S. G., & Opit, G. P. (2024). Macro- and Micro-Climatic Influence on Maize Quality and Insect Pest
Management Strategies in Small Market Storehouses in Nigeria. Discoveries in Agriculture and Food Sciences, 12(4). 01-20.
URL: http://dx.doi.org/10.14738/dafs.124.17181
structures are not effective for long term storage of grains due to their structural deficiencies.
Improved storage structures such as warehouses with appropriate management techniques
have been identified as a suitable approach for reducing grain storage losses among the rural
farmers (Mishra et al., 2012).
In Nigeria and Sub-Saharan Africa, grains are usually stored on-farm, in residence, in
community or market level storehouses, in large scale warehouses, and sometimes in national
grain silo complexes across the country (Adejumo and Raji, 2007; Adesina et al., 2019;
Olorunfemi and Kayode, 2021). The seasonal state of agricultural production in Nigeria makes
grain storage inevitable because market demand is year-round.
According to Cassada and Armstrong (2008), and Pekmez (2016), grain losses (qualitative and
quantitative) during storage can be attributed to different factors such as environmental factors
(temperature, moisture content of grains, and humidity), storage structure type, length of
storage, storage method, and biological factors (insects, pests, microorganisms and rodents).
Postharvest storage facilities were identified in a study by Niamketchi (2015) as the major
constraint of the grain value-chain in West Africa because the region is characterized with
inadequate infrastructure which limit smallholder farmers' ability to store grain crops
efficiently. This leads to a significant postharvest loss (Gerken and Morrison, 2022). Adejumo
et al. (2014) also reported that lack of good storage facilities and the high humidity prevalent
in the tropics, as it is in parts of Nigeria, cause post-harvest grain losses due to insect activity to
exceed 30%.
Warehouses are primarily constructed to provide protection of quantity and quality of stored
products (Pekmez, 2016). Generally, small storehouses are the most available storage facilities
at the market-level in Nigeria. Jayas (2012) regards a store of grains as an artificial ecosystem
in which weather plays a major role in the microclimate within the grain storage facilities.
Seasonal variations in the environmental conditions around and within storehouses influence
the microclimate of bagged grain. The magnitude of changes in these conditions and the
duration impact the quality of the stored grain. (Ileleji et al., 2015). Ileleji et al. (2015) also
reported that apart from temperature and relative humidity (RH), the microclimate created by
stored grains is affected by solar radiation, precipitation, grain moisture and gases (CO2 and
O2). However, temperature and RH constitute the main environmental factors influencing
macro- and microclimatic condition of storehouses and the stored grains. The temperature and
RH affect the equilibrium moisture content of the air surrounding the grains, and this
determines storability (Omobowale et al., 2015). Hence, the control of the storage environment
is an essential element in grain storage management as it involves, the controls of in-store
climate and infestation-pressure which can be achieved by technically sound store design and
construction (Shankar, 2014).
According to Johnson and Townsend (2009), there are three ways of preventing multiplication
of deterioration agents in stored grain namely: sanitation, inspection and protection. Sanitation
involves ensuring that grain to be stored are well dried to low moisture content and cleaned
while inspection involves regular monitoring of the stored product in order to take adequate
decision if spoilage is noticed. Protection in this concept is divided into chemical and structural