Investigation of Insecticidal Effects of Some Plant Seed Oils on Adults of Callosobruchus maculatus (Fabricius, 1775) (Coleoptera: Chrysomelidae)

1st International Mardin Scientific Research and Innovation Congress, Mardin, Türkiye, 23 - 25 Aralık 2024, ss.396-397, (Özet Bildiri)

Legumes hold a significant place in human nutrition. One of the major obstacles to ensuring

food safety is the quality deterioration and substantial post-harvest losses caused by insects

infesting these products. Callosobruchus maculatus (Fabricius) is among the most common

pests of stored cowpeas and other legumes (e.g., lentils, chickpeas, mung beans)

worlwide.Seeds damaged by the larvae of C. maculatus; exhibit decreased nutritional value,

weakened germination ability, and weight loss. Chemical applications are commonly carried

out to minimize these damages. However, the negative effects of these applications, such as

residues affecting the environment and human health, have increased the need for alternative

control methods. Currently, oils and secondary compounds derived from plants are widely

studied in pest control. The aim of this study is to determine the insecticidal potential of grape

seed oil and black seed oil, which have not been previously studied, as alternatives to chemical

use in the management of cowpea seed pests. The applications were conducted under constant

conditions of 27 ± 2°C and 65 ± 5% relative humidity using a temperature-regulated incubator.

Four different doses (50 μl, 100 μl, 150 μl, 200 μl) were tested for each oil. The experiments

were performed in four replicates, with 20 adult insects used in each replicate. In order to

calculate the percent mortality rates, controls were made at intervals of 1, 3, 6, 9, 12, 24, 48,

72, 96, 120, 144, 168, 192, 216, 240, 264, and 288 hours, and the numbers of live and dead

adults were recorded. Overall, no significant differences in mortality rates were observed

between the doses of black seed oil and grape seed oil at the initial hours. However, statistically

significant differences in mortality rates of C. maculatus were detected as exposure time

increased. At all doses of both fixed oils, 100% mortality was achieved between 216-240 hours

for grape seed oil, whereas the same was observed between 120-144 hours for black seed oil.

According to the results of probit analysis, the lethal dose (LD) for black seed oil was lower

across all doses, indicating a faster effect. Based on these findings, black seed oil appears to be

particularly promising in the control of C. maculatus.