Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil

Jean Christophe Koussoube; Ali Oura; Edouard Drabo; Koi Wenceslas Kam; Mouniratou Rahmat Ouedraogo; Antoine Waongo; Antoine Sanon; Zakaria Ilboudo

doi:doi:10.11648/j.aje.20261003.12

Research Article |

| Peer-Reviewed

Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil

Jean Christophe Koussoube^*

, Ali Oura

, Edouard Drabo

, Koi Wenceslas Kam

, Mouniratou Rahmat Ouedraogo, Antoine Waongo

, Antoine Sanon

, Zakaria Ilboudo

Published in American Journal of Entomology (Volume 10, Issue 3)

Received: 25 June 2026 Accepted: 20 July 2026 Published: 9 September 2026

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Abstract

Spermophagus niger L. is the main insect pest of stored Hibiscus sabdariffa seeds, causing significant damage through seed perforation. This study aimed to enhance our understanding of the biology and management of this pest by evaluating the influence of female age on reproductive performance, and assessing the insecticidal effect of Cymbopogon nardus essential oil (EO). The influence of females age was assessed through several reproductive and developmental parameters, including egg size, hatching rate, and development time, among other factors. The insecticidal activity of the EO was evaluated against both adults and freshly laid eggs. Increasing female age negatively affected offspring performance, resulting in smaller eggs, higher larval mortality, extended development time, and reduced adult size at emergence. Chemical characterization of C. nardus EO has shown a predominance of monoterpenes, with citronellal (23.61%), geraniol (11.63%), citronellol (9.63%), and D-limonene (1.99%). This EO exhibited significant insecticidal activity against adult S. niger, reducing both fertility and egg hatching rates. The median lethal concentration (LC₅₀) and the concentration causing 90% mortality (LC₉₀) values were estimated at 4.29 µL/L (95% CI: 3.96-4.62) and 10.52 µL/L (95% CI: 9.44-11.87), respectively. These results provide valuable insights into the biology of S. niger and demonstrate the potential of C. nardus EO as an alternative to chemical insecticides for protecting stored H. sabdariffa seeds.

Published in	American Journal of Entomology (Volume 10, Issue 3)
DOI	10.11648/j.aje.20261003.12
Page(s)	62-72
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2026. Published by Science Publishing Group

Keywords

Hibiscus sabdariffa, Spermophagus niger, Control, Cymbopogon nardus, Reproductive Performance

1. Introduction

Hibiscus sabdariffa L. (Malvales: Malvaceae) is a leafy vegetable widely cultivated in savanna and semi-arid regions

[1]

. It is highly valued for its nutritional, therapeutic, and industrial properties

[2, 3]

. Its leaves and calyxes are used in the preparation of various food products, including sauces, beverages, and jams

[4-6]

. Its seeds, which are rich in proteins, lipids, and carbohydrates

[7]

, are processed into a condiment used as a meat substitute, and known in Burkina Faso as Bi-kalaga

[8, 9]

However, the storage of H. sabdariffa seeds is severely threatened by Spermophagus niger (Motschulsky, 1866) (Coleoptera: Chrysomelidae), the main insect pest associated with this commodity

[10, 11]

. The entire life cycle of this insect occurs within the seeds, where the larvae feed on seeds the reserves before adults emerge through characteristic exit holes in the seed coats

[12]

. In the absence of effective control measures, infestation levels and associated losses may increase up to tenfold after six months of storage

[11]

In Burkina Faso, to protect H. sabdariffa seeds against S. niger, farmers and traders commonly rely on chemical insecticides

[13]

. This control strategy has many negative effects on human and animal health, as well as harmful impacts on the environment

[14, 15]

. Furthermore, the excessive use of these chemicals has led to the development of resistance in various insect pests

[14]

and has negative impacts on non-target organisms, particularly pollinators and other beneficial insects

[16]

The ability of S. niger to cause damage is closely linked to its population dynamics, which are influenced by factors affecting its morphology, physiology, and adaptation to environment

[17, 18]

. Among these factors, temperature is considered one of the most important environmental determinants of insect performance, influencing survival, fertility, and development of insects

[19]

. Previous studies on S. niger have shown that its development is optimal at 25°C but is inhibited at 20°C and 39°C

[20]

. Nevertheless, beyond abiotic factors, intrinsic biological factors such as the age of females at the time of oviposition play a decisive role in reproductive performance. Indeed, in many insects, the age of females influences fertility, egg viability, and the quality of the offspring

[21-23]

. In S. niger, this aspect has not yet been documented.

Therefore, the present study aimed to evaluate the effects of female age on egg size, egg viability, larval survival, and development time. In addition, the insecticidal activity of Cymbopogon nardus essential oil against eggs and adults of S. niger was assessed. The results obtained should contribute to a better understanding of the biology of this species and provide a scientific basis for the development of strategies for the sustainable management of H. sabdariffa seeds.

2. Materials and Methods

2.1. Study Site

The study was conducted from December 2025 to March 2026 at the Laboratory of Fundamental and Applied Entomology (LEFA), Joseph KI-ZERBO University, Ouagadougou, Burkina Faso.

2.2. Host Plant: Hibiscus sabdariffa

Seeds of Hibiscus sabdariffa (cv. Altissima variety) were purchased at the Dassasgho market (Ouagadougou, Burkina Faso). Prior to use, the seeds were cleaned and then stored at -18°C to eliminate any initial infestation.

2.3. Insect: Spermophagus niger

The Spermophagus niger strain used has been maintained at the Laboratory of Fundamental and Applied Entomology since October 2025. To maintain the strain, 20 pairs of 24-hour-old adults were introduced into Plexiglas containers (15.5 × 11.5 × 4 cm) containing 50 g of healthy sorrel seeds (cv. Altissima) and allowed to oviposit for 48 hours. The infested seeds are then transferred to a controlled-environment rearing chamber (32 ± 0.1°C, 43 ± 1% RH; L:D = 12:12) until the adults emerge. The adults are then used either for experiments or to maintain the strain using the same procedure.

2.4. Essential Oil Origin

The essential oil of Cymbopogon nardus used in this study was obtained from the Institute for Research in Applied Sciences and Technologies (IRSAT, Burkina Faso). According to the supplier, the essential oil was extracted from fresh leaves harvested in the IRSAT botanical garden by steam distillation using a Clevenger-type apparatus. The extracted oil was dissolved in absolute ethanol.

2.5. Chemical Composition of Cymbopogon nardus Essential Oil

The chemical composition of the essential oil was determined by gas chromatography–mass spectrometry (GC–MS). A 20 µL aliquot of a 1/5000 diluted sample was transferred into a vial fitted with an insert (VWR, Radnor, PA) and analyzed using a GC–MS system (Trace 1310, Thermo Fisher Scientific) equipped with a 30 m capillary column (0.25 mm i.d.; #36096-1420, Thermo Fisher Scientific). Helium was used as the carrier gas at a constant flow rate of 1 cc/min. Sample injection was performed using an autosampler (TriPlus RSH, Thermo Fisher Scientific). The oven temperature was initially maintained at 45°C for 4 min, then increased to 230°C according to a programmed temperature gradient and held for 6 min, resulting in a total run time of 28.5 min. Chromatographic peaks were manually integrated using the Chromeleon MS Quantitative Processing software (Thermo Fisher Scientific), and compound identification was achieved by comparison with spectra from the online NIST library.

2.6. Effects of Female Age on Developmental Dynamics of Spermophagus niger

A male and a female Spermophagus niger, both less than 24 hours old, were introduced into to plastic Petri dishes (9 cm × 1.5 cm) containing 20 healthy sorrel seeds of uniform size, with 15 replicates. The adults were transferred daily to a fresh batch of seeds until the females died. The length of the eggs laid was measured daily using binocular loupe LEICA EZ4HD coupled with a desktop computer and LAS EZ software. To prevent larval competition, only seeds bearing a single egg were maintained under controlled conditions (32 ± 0.1°C, 43 ± 1% RH; L = 12:12). Six (6) days after oviposition, the number of hatched and unhatched eggs was counted. Hatched eggs were identified by the presence of a reddish spot inside the chorion corresponding to the cephalic capsule of the first-instar larva

[12]

. Upon adult emergence, insects were counted and removed from the rearing boxes daily for two weeks. The following parameters were then assessed:

1) egg fertility rate (%): the ratio of the number of hatched eggs to the total number of eggs that × 100;

2) larval survival rate (%): the ratio of the number of adults emerged to the number of eggs hatched × 100;

3) development time (T): the time between egg laying and adult emergence, calculated using the formula: (D1*A1 + D2*A2 +…Dn*An) / (number of insects emerged)

[24]

; D1: day when adults began to emerge (first day); A1: number of adults that emerged on day D1.

4) Adult body size: the size of twenty (20) unsexed adult using binocular loupe LEICA EZ4HD coupled with a desktop computer and LAS EZ software.

2.7. Insecticidal Effects of Cymbopogon nardus Essential Oil on Fecundity and Mortality of Spermophagus niger

Ten (10) pairs of Spermophagus niger adults less than 24 hours old were introduced into 1-litre glass jars containing 20 g of healthy seeds of sorrel Altissima variety. The essential oil was applied by fumigation at seven concentrations: 2, 4, 6, 8, 10, 12, and 14 µL/L of air. For each treatment, the required volume of essential oil was applied to a Whatman filter paper disc (2 cm in diameter) suspended from the inner side of the jars lid before hermetically sealing the containers. An untreated control was included in the experimental design. Each treatment was replicated four times. After 24 hours of exposure, the insects were removed, and the number of dead individuals and eggs laid were recorded. fecundity was assessed as the mean number of eggs laid per female, whereas the insecticidal activity of the essential oil was evaluated based on the observed mortality rate, calculated using the following formula:

Mortalityrate(%)=(numberofdeadinsects/totalnumberofexposedinsects)×100

2.8. Impact of Cymbopogon nardus Essential Oil on Egg Hatchability

Forty (40) seeds, each bearing a 24-hour-old egg, were placed in jars identical to those used in the previous experiment. The number of seeds per experimental unit was adjusted to 100 prior to treatment. The eggs were then exposed for 24 hours to the same concentrations of C. nardus essential oil as described above. An untreated control was included, and each treatment was replicated four times. After exposure, the seeds were transferred to plastic Petri dishes (9 cm × 1.5 cm) and maintained under rearing conditions. Six (6) days later, the numbers of hatched and unhatched eggs were counted using a binocular loupe LEICA EZ4HD. Average rearing conditions were 26.9°C and 28.85% RH, with a photoperiod of 12 h light / 12 h dark. The egg hatching rate was accessed using the following formula:

Hatchingrate(%)=(numberofhatchedeggs/totalnumberoftreatedeggs)×100

2.9. Statistical Analysis

Statistical analyses were performed using R software version 4.2.2. The normality of data distribution and the homogeneity of variances were assessed using the Shapiro–Wilk and Bartlett tests, respectively. The effect of female the age in Spermophagus niger on the measured biological parameters (egg size, egg fertility rate, larval survival, development time, size of first-generation adults) was analyzed using one-way analysis of variance (ANOVA).

Similarly, the effect of Cymbopogon nardus essential oil on adult mortality, fecundity, and egg fertility were evaluated using the same statistical approach. When the assumptions required for ANOVA were not met, the Kruskal-Wallis test was applied. The lethal concentrations (LC50 and LC90), and their 95% confidence intervals were estimated using Probit analysis. The dose-response relationship between essential oil concentrations and adult mortality was modeled using a generalized linear model with a binomial error distribution and a Probit link function. The model adequacy was assessed based on the regression slope and the confidence intervals of the lethal concentration estimates. Statistical significance was determined at the 5% (p < 0.05) for all analyses.

3. Results

3.1. Effect of the Female Age on Egg Length

Egg length decreased significantly with increasing female age (F = 16.73; P = 2.28e-12). The largest Eggs were laid during the first and second days of oviposition, whereas the smallest eggs were observed on the last day (Figure 1).

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Figure 1. Mean size (mm) of Spermophagus niger eggs by female age. Bars represent means; error bars correspond to standard errors. Different alphabetic letters on the error bars indicate significant differences between means according to Fischer’s LSD test at the 5% threshold.

3.2. Effect of Female Age Hatchability, Larval Survival Rate, and Total Developmental Time

Figure 2A shows that the hatchability of eggs laid between the first and fourth days did not differ significantly, but remained significantly higher than that the eggs laid on the fifth day (F = 2.759; P = 0.0343). larval survival also varied significantly depending on females age (F = 6.058; P = 0.0003). The survival rates recorded for eggs laid on the first, third, and fourth days were statistically similar and significantly higher than those observed for eggs laid on the fifth day (Figure 2B).

The duration of development ranged from 26.49 days for eggs laid on the first day to 31.30 days for those laid on the fifth day. The shortest developmental times were observed in individuals from eggs laid during the first two days, with no significant difference between them. In contrast, eggs laid on the third and fourth days exhibited intermediate developmental durations, which were significantly longer than those recorded for the first two days but shorter than those observed for the fifth day (Figure 2C).

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Figure 2. Effect of female age on the reproductive performance of Spermophagus niger (A: mean egg hatchability (%); B: mean larval survival rate (%); C: mean development time (days)). Bars correspond to means, and error bars correspond to standard errors. Different alphabetic letters above the bars indicate significant differences between the means according to Fischer’s LSD test at the 5% significant level.

3.3. Effect of the Female Age on the Size of First-Generation Offspring

The size of the emerged adults varied significantly depending on the age of the breeding female (F = 3.539; P = 0.0091). no significant differences in adults’ size were observed among individuals originating from eggs laid during the first four days of oviposition. However, adults emerging from eggs laid on the first day were significantly larger (3.59 ± 0.27 mm) than those emerging from eggs laid on the fifth day (3.33 ± 0.34 mm) (Figure 3).

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Figure 3. Effect of female age on the mean size (mm) of emerged Spermophagus niger adults. Bars correspond to means, and error bars correspond to standard errors. Different alphabetic letters above the bars indicate significant differences between the means according to Fischer’s LSD test at the 5% significant level.

3.4. Chemical Composition of Cymbopogon nardus Essential Oil

The identified compounds accounted for approximately 96% of the total essential composition. Monoterpenoids were the predominant constituents, representing about 62% of the total composition. Among these, citronellal, geraniol, and citronellol were the most abundant compounds, occurring at proportions of 23.61%, 11.63%, and 9.63%, respectively. Sesquiterpenoids, accounted for nearly 32% of the total composition and were mainly represented by β-elemol (11.2%) and cadina-1(6), 4-diene (4.09%) (Table 1).

Table 1. Chemical composition of Cymbopogon nardus essential oil tested against adults and fresh eggs of Spermophagus niger.

Number of Peaks	Retention time	Compounds	%
		Monoterpenoid	61.83
70	8.66	ß-Myrcene	1.89
75	8.99	Pseudolimonene	0.13
79	9.44	D-Limonene	1.99
80	9.56	trans-ß-Ocimene	0.81
83	9.76	ß-Ocimene	1.19
91	10.51	Isoterpinolene	0.18
94	10.74	Linalool	0.74
104	11.66	Citronellal	23.61
105	11.82	(-)-Neoisopulegol	1.19
108	12.17	Isopulegol	0.13
114	12.88	Citronellol	9.63
115	13.07	Neral	0.30
116	13.26	Geraniol	11.63
119	13.53	α-Citral	1.27
123	13.89	Thymol	0.11
132	14.73	Citronellol acetate	2.94
133	14.83	Eugenol	0.41
135	15.14	Geranyl acetate	2.80
147	16.22	Copaen-4-α-ol	0.19
149	16.40	α-Himachalene	0.23
150	16.47	Bicyclosesquiphellandrene	0.12
208	21.95	Neodihydrocarveol	0.34
		Sesquiterpenoids	31.87
138	15.42	Elemene	3.78
142	15.9	Caryophyllene	0.17
151	16.61	Muurolene	0.52
152	16.73	Germacrene D	0.36
154	16.93	a-Muurolene	1.52
156	17.19	Cadina-1(6), 4-diene	4.09
158	17.44	(-)-α-cadinene	0.40
159	17.57	β-Elemol	11.20
162	17.98	Germacrene-4-ol	0.15
166	18.32	(-)-Globulol	0.38
170	18.58	epi-γ-Eudesmol	0.13
171	18.67	epi-γ-Eudesmol	1.66
172	18.77	α-Cadinol	7.2
181	19.58	Germacra-4(15), 5, 10 (14)-trien-1α-ol	0.14
204	21.41	Diepicedrene-1-oxide	0.17
		others	2.18
7	3.80	3-Methyl-3-pentano	0.33
32	5.58	3-Methylcyclopentanol	0.51
62	7.97	2-Nitrohexane	0.61
248	25.14	Docosane	0.21
276	26.86	Heneicosane	0.52
Total identified		95.88

Compounds less than 0.1% of the essential oil have not been listed.

3.5. Effect of Cymbopogon nardus Essential Oil on Adult of Spermophagus niger

Adult mortality in Spermophagus niger increased with increasing concentration of Cymbopogon nardus essential oil after 24 hours of exposure. It is nearly zero in the control group (1%), and then increased slightly at 2 µL/L before rising sharply at 4 µL/L (~57%), reaching approximately 96% at 14 µL/L. This dose-dependent response highlights the insecticidal activity of the essential oil (Figure 4).

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Figure 4. Effect of Cymbopogon nardus essential oil on adult Spermophagus niger after 24 hours of exposure in 1-liter glass jars. Bars correspond to means, and error bars correspond to standard errors. Different alphabetic letters above the bars indicate significant differences between the means according to Fischer’s LSD test at the 5% significant level.

Probit analysis confirmed a strong dose-response relationship, with a regression slope of 3.29. The lethal concentrations LC50 and LC90 values were 4.29 µL/L (95% CI: 3.96-4.62) and 10.52 µL/L (95% CI: 9.44-11.87), respectively. These results demonstrate the increasing efficacy of C. nardus essential oil against S. niger as increasing with increasing dose (Table 2).

Table 2. Toxicity parameters of Cymbopogon nardus essential oil against adult Spermophagus niger after 24 hours of exposure in 1-liter glass jars.

Parameters	Value (µL/L of air)	CI 95%
Slope	3.29
LC50	4.29	3.96-4.62
LC90	10.52	9.44-11.87

LC50 = Lethal Concentration; CI = Confidence Interval

3.6. Effect of Cymbopogon nardus Essential oil on Fertility and Hatch Rate of Spermophagus niger

Treatment with Cymbopogon nardus essential oil resulted in a significant reduction in the number of eggs laid by female Spermophagus niger at all tested concentrations compared with the untreated control (60.2) (F = 10.54; P = 8.46 × 10^⁻⁷) (Figure 5A). However, no significant differences in fecundity were observed among the different essential oil concentrations tested. Egg hatchability in the untreated control was approximately 94%, which was significantly higher than those observed for treated eggs, regardless of the concentration applied (Figure 5B).

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Figure 5. Effect of Cymbopogon nardus essential oil on the number of eggs laid (A) and the hatching rate (B) in Spermophagus niger after 24 hours of exposure in 1-liter glass jars. Bars correspond to means, and error bars correspond to standard errors. Different alphabetic letters above the bars indicate significant differences between the means according to Fischer’s LSD test at the 5% significant level.

4. Discussion

In many insect species, female age influences offspring quality

[25]

. Offspring produced by older females generally exhibit higher mortality rates, longer developmental times, and smaller adult sizes than those produced by younger females

[25]

. Furthermore, several studies have shown that older females often lay smaller eggs

[26, 27]

. In Callosobruchus maculatus (Coleoptera: Chrysomelidae), for example, larvae originating from eggs laid by older females are less likely to reach adulthood and require more time to complete their development

[21, 22, 28, 29]

. The results of the present study are consistent with this general trend. In Spermophagus niger, offspring performance declined with increasing female age. In fact, eggs laid on the fifth day were significantly smaller than those laid during the first few days of oviposition. This reduction in egg size was associated with increased larval mortality, a lengthening developmental time, and the emergence of smaller adults. The observed decrease in egg size may explain these results. It could reflect a gradual depletion of maternal resources, leading to the production of smaller and potentially lower-quality eggs toward the end of the oviposition period, as previously reported in others insect species

[30, 31]

. According to Fox

[32]

, females with access to food resources lay larger eggs than those subjected to nutritional stress. Similarly, maternal nutrition has been shown to increase egg size in many insect species

[33-36]

. In S. niger, emerged adults did not feed after emergence, which could support the hypothesis of a gradual depletion of resources in females. Analysis of the chemical composition of Cymbopogon nardus essential oil revealed a predominance of oxygenated monoterpenes (61.83%), mainly represented by citronellal (23.61%), geraniol (11.63%), and citronellol (9.63%), as well as limonene and other terpenic derivatives present in lower proportions. This composition is generally consistent with previous reports on C. nardus essential oil, in which these compounds are commonly identified as the major constituents

[37-39]

. However, the relatively low proportions of citronellal and geraniol observed in the present study differ from some values reported in the literature

[37, 39]

. These variations could be related to the existence of different ecotypes of the plant. Indeed, the chemical composition of essential oils is influenced by various intrinsic and extrinsic factors, including climatic conditions, geographic origin, phenological stage, plant age, and the ecological and soil characteristics of the growing environment

[40, 41]

. These compositional variations allow for the distinction of several chemotypes, which are generally defined according to the predominant compound

[42, 43]

. Based on the present results, the C. nardus essential oil studied could be classified as a citronellal chemotype. This finding is similar to the results of studies conducted in Togo by

[44, 45]

, and

[46]

, who likewise reported citronellal as the dominant constituent of C. nardus essential oils of this species.

Insecticide tests have shown that the essential oil of C. nardus exhibits insecticidal activity against S. niger. This activity resulted in a significant reduction in female fertility, as reflected by a decrease in the number of eggs laid. A significant decrease in the egg hatching rate and high adult mortality were also observed. This adulticidal toxicity was further confirmed by the LC₅₀ and LC₉₀ values, estimated at 4.29 µL/L of and 10.52 µL/L of air, respectively. This insecticidal activity of the essential oil may be attributed to its high content of oxygenated monoterpenes, particularly the acyclic monoterpenes geraniol and citronellol, as well as the monocyclic monoterpene D-limonene. These compounds are widely recognized for their insecticidal properties against numerous agricultural and stored-product insect pests. Their modes of action primarily involve disruption of the nervous system and interference with metabolic pathways essential for insect survival and development.

Geraniol, one of the major components of C. nardus essential oil, is known for its neurotoxic activity through the inhibition of acetylcholinesterase, a key enzyme involved in nerve impulses transmission. This activity has been demonstrated in several insect pest’s species, including C. maculatus, Rhyzopertha dominica, Sitophilus oryzae, and Sitophilus zeamais

[47]

. Furthermore,

[48]

reported that geraniol significantly reduced the viability of Spodoptera frugiperda eggs, even at low concentrations, by inducing morphological alterations in both the eggs and the chorion structure. Citronellol may also contributes substantially to the biological activity of the essential oil through its repellent, toxic, and growth- inhibitory effects. According to

[49]

, this compound acts primarily by disrupting the insect nervous system, altering the integrity cell membrane integrity, and interfering with respiratory processes. Furthermore, the presence of D-limonene may enhance overall insecticidal activity of the oil. Indeed, this monoterpene hydrocarbon exhibits toxic, strong repellent properties, and ovicidal activity effects against several insect pests such as C. maculatus. All of these mechanisms could explain the reduced fertility, lower egg hatching rates, and high mortality observed in S. niger following exposure to C. nardus essential oil.

5. Conclusion

The results of this study show that the age of Spermophagus niger females influences the performance of their offspring. As females age, there is a gradual decrease in maternal investment in the eggs, which results in increased larval mortality, a longer development period, and smaller adult size at emergence. The Analysis of the chemical composition of Cymbopogon nardus essential oil revealed a predominance of monoterpenes, with geraniol, citronellol, and D-limonene as the major constituents. Biological tests showed that this essential oil possesses strong insecticidal activity against S. niger adults, while significantly reducing female fertility and egg hatching rates. Overall, these results improve our understanding of the biology of S. niger and highlight the potential of C. nardus essential oil as a promising botanical alternative to chemical insecticides for the protection of stored Hibiscus sabdariffa seeds.

Abbreviations

LC50	Lethal Concentration 50%
LC90	Lethal Concentration 90%
CI	Confidence Interval
GC–MS	Gas Chromatography–Mass Spectrometry
ANOVA	Analysis of Variance

Acknowledgments

The authors gratefully acknowledge the technician from the “Laboratoire d’Entomologie Fondamentale et Appliquee (LEFA)” of “Université Joseph KI-ZERBO (UJKZ)” for his unfailing collaboration and support throughout the study.

Author Contributions

Jean Christophe Koussoube: Conceptualization, Data curation, Methodology, Writing – original draft

Ali Oura: Conceptualization, Data curation, Methodology

Edouard Drabo: Conceptualization, Data curation, Methodology

Koi Wenceslas Kam: Writing – review & editing

Mouniratou Rahmat Ouedraogo: Data curation

Antoine Waongo: Supervision, Validation

Antoine Sanon: Supervision, Validation

Zakaria Ilboudo: Supervision, Validation

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Schippers, R. R. African Indigenous Vegetable: an Overview of the Cultivated Species. Natural Resources Institute/ACP-EU. Technical Center for Agricultural and Rural Cooperation, Chatam, U. K. 2000, 1-124.
[2]	Lépengué, A. N., M’batchi, B., Aké, S. Impact de Phoma sabdariffae Sacc. sur la croissance et la valeur marchande de la roselle (Hibiscus sabdariffa L. var. sabdariffa) au Gabon. Revue Ivoirienne des Sciences et Technologie. 2007, 10, 207-216, https://doi.org/10.4314/aga.v22i1.62307
[3]	Mahadevan, N., Shivali, K. P. Hibiscus sabdariffa Linn. An overview. Natural Product Radiance. 2009, 8(1), 77-83.
[4]	Bako, I. G., Mabrouk, M. A., Abubakar, A. Antioxidant effect of ethanolic seed extract of Hibiscus sabdariffa Linn (Malvaceae) alleviate the toxicity induced by chronic administration of sodium nitrate on some haematological parameters in Wistars rats. Advance Journal of Food Science and Technology. 2009, 1(1), 39-42.
[5]	Bolade, M. K., Oluwalana, I. B., Ojo, O. Commercial practice of roselle (Hibiscus sabdariffa L.) beverage production: Optimization of hot water extraction and sweetness level. World Journal of Agricultural Sciences. 2009, 5(1), 126-131.
[6]	Ismail, A., Ikram, E. H. K., Nazri, H. S. M. Roselle (Hibiscus sabdariffa L.) seeds nutritional composition protein quality and health benefits. Food. 2008, 2(1), 1-16.
[7]	Cisse, M., Dornier, M., Sakho, Ndiaye, A., Reynes, M., Sock, O. Le Bissap (Hibiscus sabdariffa L.): Composition et Principales Utilisations. Fruits. 2008, 64(3), 179–193, https://doi.org/10.1051/fruits/2009013
[8]	Bengaly, M., Béré, A., Traoré, A. The chemical composition of bikalga, a traditional fermented roselle (Hibiscus sabdariffa L.) seeds condiment. Part II: evaluation of mineral, total polyphenols and phytic acid content, predicting the iron bioavailability. Electronic Journal of Food and Plants Chemistry. 2006, 1, 7–11.
[9]	Atta, S., Sarr, B., Diallo, A. B., Bakasso, Y., Lona, I., Saadou, M. Nutrients composition of calyces and seeds of three Roselle (Hibiscus sabdariffa L.) ecotypes from Niger. African Journal of Biotechnology. 2013, 12, 4174- 4178.
[10]	Amadou, L., Baoua, I. B., Baributsa, D., Williams, S. B., Murdoch, L. L. Triple bag hermetic technology for controlling a bruchid (Spermophagus sp.) (Coleoptera, Chrysomelidae) in stored Hibiscus sabdariffa grain. Journal of Stored Product Research. 2016, 69, 22–25. https://doi.org/10.1016/j.jspr.2016.05.004
[11]	Koussoubé, J. C., Mbaye, F., Mbacké Dia, C. A. K., Mbacké, S., Sanon, A. Genetic characterization of Spermophagus niger (Coleoptera: Chrysomelidae: Bruchinae: Amblycerini) pest associated to seeds of Sorrel (Hibiscus sabdariffa L.) in Burkina Faso. South Asian Journal of Experimental Biology. 2016, 6, 7–14. https://sajeb.org/index.php/sajeb/article/view/237
[12]	Sanon, A., Koussoube, J. C., Ba, M. N., Dabire-Binso, L. C., Sembene, M. Report on Spermophagus niger Motschulsky, 1866 (Coleoptera: Chrysomelidae: Bruchinae: Amblycerini) infesting the seeds of roselle, Hibiscus sabdariffa L. (Malvaceae) during post-harvest storage in Burkina Faso. Journal of Stored Products Research. 2017, 72, 64–67. https://doi.org/10.1016/j.jspr.2017.04.002
[13]	Kabore, E., Kambou, S. F., Kam, K. W., Koussoube, J. C., Ki, K. F. M., Sanon, A., Ilboudo, Z. Post-Harvest Management and Phytosanitary Practices Used to Preserve Sorrel Seeds, Hibiscus sabdarffa L. In Burkina Faso. International Journal of Innovation and Applied Studies. 2024, 43, 685–695.
[14]	Boyer, S., Zhang, H., Lemperiere, G. A review of control methods and resistance mechanisms in stored-product insects. Bulletin of Entomological Research. 2012, 102, 213 229. https://doi.org/10.1017/S0007485311000654
[15]	Bumbrah, G. S., Krishan, K., Kanchan, T., Sharma, M., Sodhi, G. S. Phosphide poisoning: a review of literature. Forensic Science International. 2012, 214, 1-6. https://doi.org/10.1016/j.forsciint.2011.06.018
[16]	Adler, L. S., Hazzard, R. V. Comparison of perimeter trap crop varieties: Effects on herbivory, pollination, and yield in butternut squash. Environmental Entomology. 2009, 38, 207-215. https://doi.org/10.1603/022.038.0126
[17]	Karl, I., Stoks, R., De Block, M., Janowitz, S. A., Fischer, K. (2011). Temperature extremes and butterfly fitness: conflicting evidence from life history and immune function. Global Change Biology. 2011, 17(2), 676-687. https://doi.org/10.1111/j.1365-2486.2010.02277.x
[18]	Nyamukondiwa, C., Weldon, C. W., Chown, S. L., le Roux, P. C., Terblanche, J. S. (2013). Thermal biology, population fluctuations and implications of temperature extremes for the management of two globally significant insect pests. Journal of Insect Physiology. 2013, 59(12), 1199-1211. https://doi.org/10.1016/j.jinsphys.2013.09.004
[19]	Chapman, T., Miyatake, T., Smith, H. K., Partridge, L. (1998). Interactions of mating, egg production and death rates in females of the Mediterranean fruit fly, Ceratitis capitata. Proceedings of the Royal Society B. 1998, 265, 1879–1894. https://doi.org/10.1098/rspb.1998.0516
[20]	Koussoube, J. C., Yamkoulga, M., Waongo, A., Ilboudo, Z., Sanon, A. How the increase in temperatures impact the development of Spermophagus niger (Motschulsky) (Coleoptera: Chrysomelidae) a major pest of stored sorrel seeds, in a context of climate change. African Association of Insects Scientists (AAIS) Book of Proceedings: 18-22 Nov. Lusaka, Zambia. 2024, pp. 213-220. https://doi.org/10.1007/s42690-025-01689-z
[21]	Fox, C. W., Dingle, H. Dietary mediation of maternal age effects on offspring performance in a seed beetle (Coleoptera: Bruchidae). Functional Ecology. 1994, 8, 600-606. https://doi.org/10.2307/2389921
[22]	Fox, C. W., Bush, M. L., Wallin, W. G. Maternal age affects offspring lifespan of the seed beetle, Callosobruchus maculatus. Functional Ecology. 2003, 17, 811-820. https://doi.org/10.1111/j.1365-2435.2003.00799.x
[23]	Mishra, G., Omkar, O. Influence of parental age on reproductive performance of an aphidophagous ladybird, Propylea dissecta (Mulsant). Journal of Applied Entomology. 2004, 128 (9-10), 605-609. https://doi.org/10.1111/j.1439-0418.2004.00903.x
[24]	Howe, R. W. A Parameter for Expressing the Suitability of the Environment for Insect Development. Journal of Stored Products Research. 1971, 7 (1), 63–65, https://doi.org/10.1016/0022474X(71)90039-7
[25]	Mousseau, T. A., Dingle, H. Maternal effects in insect life histories. Annual Review of Entomology. 1991, 36, 511-534. https://doi.org/10.1146/annurev.en.36.010191.002455
[26]	Jones, R. E., Hart, J. R., Bull, G. D. Temperature, size and egg production in the cabbage butterfly, Pieris rapae L. Australian Journal of Zoology. 1982, 30, 223-232. https://doi.org/10.1071/ZO9820223
[27]	Wiklund, C., Persson, B. Fecundity, and the relation of egg weight to offspring fitness in the speckled wood butterfly Pararge aegeria, or why don't butterfly females lay more eggs? Oikos. 1983, 40, 53-63. https://doi.org/10.2307/3544198
[28]	Wasserman, S. S., Asami, T. The effect of maternal age upon fitness of progeny in the southern cowpea weevil, Callosobruchus maculatus. Oikos. 1985, 45, 191-196. https://doi.org/10.2307/3565705
[29]	Fox, C. W. A quantitative genetic analysis of oviposition preference and larval performance on two hosts in the bruchid beetle, callosobruchus maculatus. Evolution. 1993a, 47(1), 166-175. https://doi.org/10.1111/j.1558-5646.1993.tb01207.x
[30]	Richards, L. J., Myers, J. H. Maternal influences on size and emergence time of the cinnabar moth. Canadian Journal of Zoo1ogy. 1980, 58, 1452-1457. https://doi.org/10.1139/z80-199
[31]	Wiklund, C., Karlsson, B. Egg size variation in satyrid butterflies: adaptive vs. historical, "Bauplan", and mechanistic explanations. Oikos. 1984, 43(3), 391-400. https://doi.org/10.2307/3544158
[32]	Fox, C. W. The influence of maternal age and mating frequency on egg size and offspring performance in Callosobruchus maculatus (Coleoptera: Bruchidae). Oecologia. 1993, 96, 139 146. https://doi.org/10.1007/BF00318042
[33]	Harvey, G. T. Environmental and genetic effects on mean egg weight in spruce budworm (Lepidoptera: Tortricidae). The Canadian Entomologist. 1983, 115, 1109-1117. https://doi.org/10.4039/Ent1151109-9
[34]	Murphy, D. D., Launer, A. E., Ehrlich, P. R. The role of adult feeding in egg production and population dynamics of the checkerspot butterfly Euphydryas editha. Oecologia. 1983, 56, 257-263.
[35]	Steinwascher, K. Egg size variation in Aedes aegypti: relationship to body size and other variables. The American Midland Naturalist. 1984, 112, 76-84. https://doi.org/10.2307/2425459
[36]	Wallin, H., Chiverton, P. A., Ekbom, B. S., Borg, A. Diet, fecundity and egg size in some polyphagous predatory carabid beetles. Entomologia Experimentalis and Applicata. 1992, 65, 129-140. https://doi.org/10.1111/j.1570-7458.1992.tb01636.x
[37]	Nyamador, S. W., Ketoh, G. K., Koumaglo, H. K., Glitho, I. A. Activités Ovicide et Larvicide des Huiles Essentielles de Cymbopogon giganteus Chiov. et de Cymbopogon nardus L. Rendle sur les stades immatures de Callosobruchus maculatus F. et de Callosobruschus subinnotatus Pic. (Coleoptera: Bruchidae). Journal de la Société Ouest Africaine de Chimie. 2010, 29, 67-79.
[38]	Ouedraogo, I., Sawadogo, A., Nebie, R. C., Dakouo, D. Evaluation de la toxicité des huiles essentielles de Cymbopogon nardus (L) et Ocimum gratissimum (L) contre Sitophilus zeamais Motsch et Rhyzopertha dominica F, les principaux insectes nuisibles aux maïs en stockage au Burkina Fasso. International Journal of Biological and Chemical Sciences. 2016, 10 (2), 695-705. http://dx.doi.org/10.4314/ijbcs.v10i2.20
[39]	Alassane, A. N., Amidou, K., Zannou, E. T., Salifou, S. Efficacité insecticide in vitro et in vivo de l’huile essentielle de Cymbopogon nardus (Poaceae) sur les poux Menopon gallinae, parasites des volailles. Journal of Animal and Plant Sciences. 2023, 56(2), 10320- 10326. https://doi.org/10.35759/JAnmPlSci.v56-2.3
[40]	Gnamkoulamba, A. Etude agronomique et chimique de Aoellanthus pubescens Benth. Et évaluation des propriétés germicides et insecticides de son huile essentielle. Mémoire d'Ingénieur Agronome, Ecole Supérieure d’Agriculture, Université du Bénin, Lomé. 1999, 74 p.
[41]	Seri-Kouassi, B. P. Entomofaune du Niébé (Vigna unguiculata L. WALP) et impact des huiles essentielles extraites de neuf plantes locales sur la reproduction de Callosobruchus maculatus FAB. (Coleoptera Bruchidae) en Côte d’Ivoire. Thèse de Doctorat d’Etat ès sciences naturelles, UFR Biosciences, Univ. Cocody Abidjan, Côte d’Ivoire. 2004, 199 p.
[42]	Walla, B. Mémoire d’Ingénieur Agronome. École Supérieure d’Agronomie (ESA), Université du Bénin, Lomé, Togo. 1996, 54 p.
[43]	Sanda, K., Koba, K., Nambo, P., Gaset, A. Chemical investigation of Ocimum species growing in Togo. Flavour and Fragrance Journal. 1998, 13(4), 226-232. 10.1002/(SICI)1099-1026(199807)13:4<226::AID-FFJ717>3.0.CO;2-H
[44]	Koumaglo, H. K., Akpangana, K., Glitho, A. I., Garneau, F. X., Gagnon, H., Jean, F. I., Moudachirou, M., Addae-Mensah, I. Geranial and neral, major components of Lippia multiflora Mold. leaf oil. Journal of Essential Oil Research. 1996, 8, 237-240. https://doi.org/10.1080/10412905.1999.9701097
[45]	Ketoh, K. Utilisation des huiles essentielles de quelques plantes aromatiques du Togo comme biopesticides dans la gestion des stades de développement de Callosobruchus maculatus. Thèse de Doctorat, Université du Bénin, Lomé (Togo). 1998.
[46]	Ketoh, K. G., Glitho, I. A., Koumaglo, H. K. Activité comparée des huiles essentielles de trois espèces du genre Cymbopogon (Poaceae). Journal de la Société Ouest-Africaine de Chimie. 2004, 18, 21-34.
[47]	López, M. D., Pascual-Villalobos, M. J. Mode of inhibition of acetylcholinesterase by monoterpenoids and implications for pest control. Industrial Crops Products. 2010, 31, 284-288. https://doi.org/10.1016/j.indcrop.2009.11.005
[48]	Visakh, N. U., Pathrose, B., Chellappan, M., Ranjith, M. T., Sindhu, P. V., Mathew, D. Extraction and chemical characterization of agro-waste from turmeric leaves as a source of bioactive essential oils with insecticidal and antioxidant activities. Waste Management. 2023, 69, 1-10. https://doi.org/10.1016/j.wasman.2023.06.030
[49]	Nerio, L. S., Olivero-Verbel, J., Stashenko, E. Repellent activity of essential oils: A review. Bioresource Technology. 2010, 101, 372-378. https://doi.org/10.1016/j.biortech.2009.07.048

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Koussoube, J. C., Oura, A., Drabo, E., Kam, K. W., Ouedraogo, M. R., et al. (2026). Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil. American Journal of Entomology, 10(3), 62-72. https://doi.org/10.11648/j.aje.20261003.12

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Koussoube, J. C.; Oura, A.; Drabo, E.; Kam, K. W.; Ouedraogo, M. R., et al. Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil. Am. J. Entomol. 2026, 10(3), 62-72. doi: 10.11648/j.aje.20261003.12

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Koussoube JC, Oura A, Drabo E, Kam KW, Ouedraogo MR, et al. Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil. Am J Entomol. 2026;10(3):62-72. doi: 10.11648/j.aje.20261003.12

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@article{10.11648/j.aje.20261003.12,
  author = {Jean Christophe Koussoube and Ali Oura and Edouard Drabo and Koi Wenceslas Kam and Mouniratou Rahmat Ouedraogo and Antoine Waongo and Antoine Sanon and Zakaria Ilboudo},
  title = {Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil},
  journal = {American Journal of Entomology},
  volume = {10},
  number = {3},
  pages = {62-72},
  doi = {10.11648/j.aje.20261003.12},
  url = {https://doi.org/10.11648/j.aje.20261003.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.aje.20261003.12},
  abstract = {Spermophagus niger L. is the main insect pest of stored Hibiscus sabdariffa seeds, causing significant damage through seed perforation. This study aimed to enhance our understanding of the biology and management of this pest by evaluating the influence of female age on reproductive performance, and assessing the insecticidal effect of Cymbopogon nardus essential oil (EO). The influence of females age was assessed through several reproductive and developmental parameters, including egg size, hatching rate, and development time, among other factors. The insecticidal activity of the EO was evaluated against both adults and freshly laid eggs. Increasing female age negatively affected offspring performance, resulting in smaller eggs, higher larval mortality, extended development time, and reduced adult size at emergence. Chemical characterization of C. nardus EO has shown a predominance of monoterpenes, with citronellal (23.61%), geraniol (11.63%), citronellol (9.63%), and D-limonene (1.99%). This EO exhibited significant insecticidal activity against adult S. niger, reducing both fertility and egg hatching rates. The median lethal concentration (LC₅₀) and the concentration causing 90% mortality (LC₉₀) values were estimated at 4.29 µL/L (95% CI: 3.96-4.62) and 10.52 µL/L (95% CI: 9.44-11.87), respectively. These results provide valuable insights into the biology of S. niger and demonstrate the potential of C. nardus EO as an alternative to chemical insecticides for protecting stored H. sabdariffa seeds.},
 year = {2026}
}

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TY - JOUR
T1 - Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil
AU - Jean Christophe Koussoube
AU - Ali Oura
AU - Edouard Drabo
AU - Koi Wenceslas Kam
AU - Mouniratou Rahmat Ouedraogo
AU - Antoine Waongo
AU - Antoine Sanon
AU - Zakaria Ilboudo
Y1 - 2026/09/09
PY - 2026
N1 - https://doi.org/10.11648/j.aje.20261003.12
DO - 10.11648/j.aje.20261003.12
T2 - American Journal of Entomology
JF - American Journal of Entomology
JO - American Journal of Entomology
SP - 62
EP - 72
PB - Science Publishing Group
SN - 2640-0537
UR - https://doi.org/10.11648/j.aje.20261003.12
AB - Spermophagus niger L. is the main insect pest of stored Hibiscus sabdariffa seeds, causing significant damage through seed perforation. This study aimed to enhance our understanding of the biology and management of this pest by evaluating the influence of female age on reproductive performance, and assessing the insecticidal effect of Cymbopogon nardus essential oil (EO). The influence of females age was assessed through several reproductive and developmental parameters, including egg size, hatching rate, and development time, among other factors. The insecticidal activity of the EO was evaluated against both adults and freshly laid eggs. Increasing female age negatively affected offspring performance, resulting in smaller eggs, higher larval mortality, extended development time, and reduced adult size at emergence. Chemical characterization of C. nardus EO has shown a predominance of monoterpenes, with citronellal (23.61%), geraniol (11.63%), citronellol (9.63%), and D-limonene (1.99%). This EO exhibited significant insecticidal activity against adult S. niger, reducing both fertility and egg hatching rates. The median lethal concentration (LC₅₀) and the concentration causing 90% mortality (LC₉₀) values were estimated at 4.29 µL/L (95% CI: 3.96-4.62) and 10.52 µL/L (95% CI: 9.44-11.87), respectively. These results provide valuable insights into the biology of S. niger and demonstrate the potential of C. nardus EO as an alternative to chemical insecticides for protecting stored H. sabdariffa seeds.
VL - 10
IS - 3
ER -

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Author Information

Jean Christophe Koussoube

Department of Plant Production and Agronomy, Tenkodogo University Center, Tenkodogo, Burkina Faso;Department of Animal Biology and Physiology, Joseph Ki-Zerbo University, Ouagadougou, Burkina Faso

Contact Email

http://orcid.org/0009-0001-1107-449X
Ali Oura

Department of Animal Biology and Physiology, Joseph Ki-Zerbo University, Ouagadougou, Burkina Faso

http://orcid.org/0009-0007-8634-1920
Edouard Drabo

Department of Animal Biology and Physiology, Joseph Ki-Zerbo University, Ouagadougou, Burkina Faso;Department of Plant Production, Institute of Environment and Agricultural Research, Ouagadougou, Burkina Faso

http://orcid.org/0009-0001-0344-506X
Koi Wenceslas Kam

Department of Animal Biology and Physiology, Joseph Ki-Zerbo University, Ouagadougou, Burkina Faso;Department of Forest Engineering, Yembila Abdoulaye Toguyeni University, Fada N'Gourma, Burkina Faso

http://orcid.org/0000-0001-8384-4425
Mouniratou Rahmat Ouedraogo

Department of Animal Biology and Physiology, Joseph Ki-Zerbo University, Ouagadougou, Burkina Faso
Antoine Waongo

Department of Animal Biology and Physiology, Joseph Ki-Zerbo University, Ouagadougou, Burkina Faso;Department of Plant Production, Institute of Environment and Agricultural Research, Ouagadougou, Burkina Faso

http://orcid.org/0000-0003-1109-2361
Antoine Sanon

Department of Animal Biology and Physiology, Joseph Ki-Zerbo University, Ouagadougou, Burkina Faso

http://orcid.org/0000-0002-2046-8503
Zakaria Ilboudo

Department of Animal Biology and Physiology, Joseph Ki-Zerbo University, Ouagadougou, Burkina Faso

http://orcid.org/0000-0003-1029-2644

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Koussoube, J. C., Oura, A., Drabo, E., Kam, K. W., Ouedraogo, M. R., et al. (2026). Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil. American Journal of Entomology, 10(3), 62-72. https://doi.org/10.11648/j.aje.20261003.12

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Koussoube, J. C.; Oura, A.; Drabo, E.; Kam, K. W.; Ouedraogo, M. R., et al. Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil. Am. J. Entomol. 2026, 10(3), 62-72. doi: 10.11648/j.aje.20261003.12

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AMA Style

Koussoube JC, Oura A, Drabo E, Kam KW, Ouedraogo MR, et al. Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil. Am J Entomol. 2026;10(3):62-72. doi: 10.11648/j.aje.20261003.12

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@article{10.11648/j.aje.20261003.12,
  author = {Jean Christophe Koussoube and Ali Oura and Edouard Drabo and Koi Wenceslas Kam and Mouniratou Rahmat Ouedraogo and Antoine Waongo and Antoine Sanon and Zakaria Ilboudo},
  title = {Influence of Female Age on the Reproductive Performance of Spermophagus niger Motschulsky and the Insecticidal Activity of Cymbopogon nardus (L.) Rendle Essential Oil},
  journal = {American Journal of Entomology},
  volume = {10},
  number = {3},
  pages = {62-72},
  doi = {10.11648/j.aje.20261003.12},
  url = {https://doi.org/10.11648/j.aje.20261003.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.aje.20261003.12},
  abstract = {Spermophagus niger L. is the main insect pest of stored Hibiscus sabdariffa seeds, causing significant damage through seed perforation. This study aimed to enhance our understanding of the biology and management of this pest by evaluating the influence of female age on reproductive performance, and assessing the insecticidal effect of Cymbopogon nardus essential oil (EO). The influence of females age was assessed through several reproductive and developmental parameters, including egg size, hatching rate, and development time, among other factors. The insecticidal activity of the EO was evaluated against both adults and freshly laid eggs. Increasing female age negatively affected offspring performance, resulting in smaller eggs, higher larval mortality, extended development time, and reduced adult size at emergence. Chemical characterization of C. nardus EO has shown a predominance of monoterpenes, with citronellal (23.61%), geraniol (11.63%), citronellol (9.63%), and D-limonene (1.99%). This EO exhibited significant insecticidal activity against adult S. niger, reducing both fertility and egg hatching rates. The median lethal concentration (LC₅₀) and the concentration causing 90% mortality (LC₉₀) values were estimated at 4.29 µL/L (95% CI: 3.96-4.62) and 10.52 µL/L (95% CI: 9.44-11.87), respectively. These results provide valuable insights into the biology of S. niger and demonstrate the potential of C. nardus EO as an alternative to chemical insecticides for protecting stored H. sabdariffa seeds.},
 year = {2026}
}

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