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ABSTRACTControlling grain temperatures is the main approach employed in large commercial warehouses to maintain quality and prevent infestation by insects and fungi. Large commercial warehouses in northeast China have been utilizing inner cyclic cooling aeration (ICCA), a newly developed method for managing summertime temperatures, haphazardly and without tight standards. We utilized a homemade detector to track the temperature, humidity, and CO2 concentrations of maize that was held for four years under ICCA treatment. The monitoring occurred every week, specifically from July 1st to September 30th. In addition, we conducted weekly tests to determine the moisture content (MC) and free fatty acids (FFA) of the stored maize samples. Without the use of ICCA, the average temperature of the stored maize above a depth of 3.5 m ranged from 20°C to 28°C, and the relative humidity (RH) in the headspace was typically higher than 75%. However, when ICCA was applied, the average temperature could be maintained at 22°C, and the RH was below 65% for most of the time. In the first year, the MC of the stored maize at a depth of 1.0 m experienced a loss of approximately 0.5%. However, for one year, there was no significant loss in the MC of the maize stored at the same depth. Furthermore, the FFA in the stored maize at a depth of 1 m increased by 1–5 mg KOH/100 g. The use of ICCA effectively controls the temperature and RH in the stored maize, reducing the risk of insect and fungal reproduction.

The repellency of solvent extracts of Calpurnia aurea leaves was evaluated on the maize weevils and the red flour beetles. Nine-cm Whatman number 1 filter paper that is partitioned into treatment, neutral and non-treatment portions was used for the experiment. Each solvent extract treatment was applied at 2.5, 5 and 10% rates. Insects were released in the neutral portion, while the untreated part served as a control. A choice bioassay experimental method that is laid down in a completely randomized design within three replications was used. 5 and 10% rates of the polar solvent extracts of Calpurnia aurea leaves induced significantly (p

Millettia ferruginea leaf solvent extracts were tested for repellency against the most important pests of stored maize; the maize weevils and the red flour beetles. 2.5%, 5%, and 10% dosages were applied in 9 cm Whatman number 1 filter paper, with dividing it into three parts. The untreated portion was used as a control, while the neutral was served as the insect release portion. Significantly (P 55%) repellency was recorded in all M. ferruginea leaf polar solvent extracts applied at rates of 5% and 10%, at 2 days after treatment than nonpolar and partial polar solvent extract treatments, and the untreated check. One hundred percent weevils and beetles repellency were recorded in all M. ferruginea leaf polar extract treatments applied at rates of 10%, at 3 days after treatment. Therefore, the M. ferruginea leaf polar solvent extracts were potent, and they could be used in the management of the maize weevils and the red flour beetles in stored maize, at 5% and 10% dosages, under farmers’ storage conditions in Ethiopia. However, the crude extracts effect on a human beings, natural enemies, and the cost-effectiveness under farmers’ storage conditions needs further study.