Exploring the Role of Earthworms and Beneficial Insects in Sustainable Agriculture

940 ISSN Online: 3007-1941 ISSN Print: 3007-1933 Exploring the Role of Earthworms and Beneficial Insects in Sustainable Agriculture Article Details A B S T R A C T Keywords: Earthworms, Beneficial Insects, Soil Fertility, Biological Control, Sustainable Agriculture, Crop Productivity Mashahood Ali Khan Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Punjab, Pakistan Abubakr Saddique Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Punjab, Pakistan Muhammed Zahid Iqbal* Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Punjab, Pakistan Email: m[email protected] Owais Raza Department of Entomology, Faculty of Agricultural Sciences, University of the Punjab Lahore, Pakistan Tahammal Hussain Department of Entomology, University of Agriculture, Faisalabad, Punjab, Pakistan Muhammad Omer Farooq Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Punjab, Pakistan Muhammad Rizwan Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Punjab, Pakistan Muhammad Gul Zaman Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Punjab, Pakistan Rida Akbar Department of Entomology, Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Punjab, Pakistan Obaiba Khalid Ansari Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Punjab, Pakistan This study examined the synergistic effects of earthworms (Eisenia fetida) and beneficial insects (Coccinella septempunctata and Chrysoperla carnea) on enhancing soil fertility, pest control, and crop yield in sustainable farming practices. Field tests utilized a randomized full-block design comprising three treatments: control, earthworm inoculation, and beneficial insect release. Soil physicochemical parameters, insect and predator populations, and crop yield characteristics were assessed during two agricultural seasons. The results indicated that plots treated with earthworms demonstrated significantly elevated levels of organic carbon (1.56 ± 0.04%), total nitrogen (0.11 ± 0.01%), and microbial biomass carbon (315.4 ± 12.3 mg kg⁻¹) compared to control plots, signifying enhanced soil biological activity. The introduction of beneficial insects decreased aphid and whitefly populations by 72% and 65%, respectively, while increasing predator abundance and biological control efficacy by 78.5%. Crop output in the biologically managed plots increased by 34.8%, including significant enhancements in fruit quality, such as elevated vitamin C and total soluble solids content. Correlation analysis revealed robust positive associations between soil organic carbon and yield (r = 0.86, P < 0.01). The results indicated that the incorporation of soil fauna and natural predators had a synergistic impact, enhancing ecological resilience and productivity. This biologically based method offers a feasible and environmentally sustainable alternative to chemical inputs, highlighting the significance of earthworms and beneficial insects as crucial contributors to sustainable agricultural intensification. Mashahood Ali Khan1, Abubakr Saddique2, Muhammed Zahid Iqbal3*, Owais Raza4, Tahammal Hussain5, Muhammad Omer Farooq6, Muhammad Rizwan7, Muhammad Gul Zaman8, Rida Akbar9, Obaiba Khalid Ansari10 https://msra.online/index.php/Journal/about https://msra.online/index.php/Journal/about Volume 3, Issue 4 (2025) 941 https://msra.online/index.php/Journal/about Volume 3, Issue 4 (2025) INTRODUCTION: Sustainable agriculture seeks to optimize productivity and stability with the efficient use of natural resources and biological processes. In this regard, soil fauna and beneficial arthropods are essential for enhancing soil fertility, controlling pests, and increasing crop yields. Earthworms, also considered ecosystem engineers, play a central role in structuring soils, decomposing organic matter, and mineralizing nutrients (Fonte et al., 2023). Their burrowing activities can increase soil aeration, infiltration, and microbial activity, thereby promoting greater nutrient availability for plants (Li et al., 2024). The breakdown of organic residues and the release of plant-available nutrients enhance sustainable soil fertility through vermicomposting processes with species such as Eisenia fetida (Ahmed & Al-Mutairi, 2022). The importance of these organisms for global food security is becoming more widely acknowledged, with the presence of earthworms alone estimated to increase crop yields by almost 25% (Ganapathy et al., 2025). Alongside soil organisms, beneficial insects are another important group favoring agroecosystem sustainability. These insects include predators, such as Coccinella septempunctata and Chrysoperla carnea, parasitoids, and pollinators, all of which help reduce pest populations and increase yield (Jarpla et al., 2024). It has been demonstrated that combining beneficial insects in cropping systems can lead to a 70% decrease in pest pressure while simultaneously increasing biodiversity indices (Arnold et al., 2021). Furthermore, the ecological stability of predator fauna and necking in field margin plant diversity, along with staggered planting, has been proven to enhance habitat provision for natural enemies, promoting biological pest control during alley cropping set-up (Datta et al., 2025). Recent technological advances in precision agriculture, such as image-based pest monitoring (Ratnayake et al., 2023), underline the increasing significance of beneficial insects in sustainable pest management. As highlighted by Gill (2013), habitat restoration and reduced use of pesticides are still required to ensure the survival of these organisms and their ecological functions. The combination of earthworms and beneficial soil insects represents a synergistic strategy for enhancing soil fertility, pest management, and the general health of agroecosystems. Previous meta‐analyses have demonstrated that the joint effects of belowground and aboveground biotic agents promote soil enzymatic activities and pest regulation, which contribute to improving crop productivity and resistance (Bashir et al., 2023). This idea fits within the sustainable intensification framework, which suggests replacing external chemical inputs with ecological functions. Furthermore, beneficial insects reinforce the soil fauna by providing biological control services, including reducing pest resurgence. Collectively, these biological ingredients are the basis of sustainable agricultural systems, which not only increase yields but also conserve biodiversity and soil quality for future generations. Thus, the objective of this study was to test the independent and interactive influences of earthworms and beneficial insects on soil health, pest control, and crop yield under organic field conditions to provide empirical data from an applied perspective in sustainable agriculture. Methodology Research Design This study employed a mixed experimental and analytical design to investigate the ecological and agronomic roles of earthworms and beneficial insects in sustainable agriculture. The research integrated controlled field experiments with laboratory and statistical analyses to assess soil fertility, crop productivity, and biological pest suppression. A randomized complete block design (RCBD) was adopted with three treatments: (i) plots inoculated with earthworms, (ii) plots augmented with beneficial insect populations, and (iii) untreated control plots. Each treatment was replicated four times to ensure statistical reliability. The experiment spanned two consecutive cropping seasons under open-field organic management conditions. Study Site and Experimental Conditions 942 https://msra.online/index.php/Journal/about Volume 3, Issue 4 (2025) The field experiment was conducted at the Department of Sustainable Agriculture Experimental Farm, located in a subtropical agroecological zone (31°25′ N, 73°05′ E). The site is characterized by loamy soil (pH 7.4), an average annual rainfall of 450 mm, and a mean temperature range of 18–36°C. Tomato (Solanum lycopersicum L.) was chosen as the test crop due to its sensitivity to soil biological activity and pest incidence. Each experimental plot measured 3 m × 3 m and was managed under uniform irrigation and organic nutrient conditions using drip systems. No synthetic fertilizers or pesticides were applied during the study period to maintain ecological validity. Earthworm Inoculation and Monitoring The species Eisenia fetida was selected due to its high adaptability, rapid organic matter decomposition rate, and well-established contribution to soil nutrient cycling. Adult worms were introduced into designated plots at a density of 100 individuals per square meter two weeks before transplanting tomato seedlings. Vermicompost prepared from cattle manure and crop residues was applied at 10 t ha⁻¹ to improve habitat quality. Monthly monitoring included assessment of earthworm population density and biomass using handsorting and formalin extraction techniques Soil samples (0–15 cm depth) were analyzed for organic matter, total nitrogen, and microbial biomass carbon (MBC) to quantify biological enrichment. Beneficial Insect Introduction and Observation Two key beneficial insect species were selected: Coccinella septempunctata (ladybird beetle) as a predator of aphids and Chrysoperla carnea (green lacewing) as a predator of lepidopteran larvae and whiteflies. Adult beetles and lacewing larvae were released into designated plots at densities of 30 and 40 individuals per plot, respectively, at the onset of pest infestation. Weekly observations were conducted to monitor pest populations, predator abundance, and survival rates. Sweep netting and yellow sticky traps were employed for insect sampling, and predator–prey ratios were used to estimate natural biological control efficacy. Soil and Plant Sampling Protocols Soil samples were collected from each plot before sowing and after harvest to measure changes in soil physicochemical and biological parameters. Variables analyzed included pH, organic carbon, total nitrogen, available phosphorus, exchangeable potassium, and enzymatic activities (urease, dehydrogenase, and phosphatase). Plant growth and yield parameters—plant height, leaf area index, fruit number, and total biomass—were measured at 30, 60, and 90 days after transplanting. Fruit quality indicators such as vitamin C content, total soluble solids (TSS), and firmness were determined following AOAC (2019) standard protocols. Pest and Natural Enemy Dynamics Pest and predator populations were monitored at weekly intervals. Pest density was determined by counting individuals on ten randomly selected plants per plot. Beneficial insect abundance was simultaneously recorded. Biological control efficiency (BCE) was calculated as: BCE = (Pc− Pt) Pc ×100 where P_c = pest population in control plots and P_t = pest population in treated plots. Species diversity was quantified using Shannon–Wiener (H′) and Simpson’s (D) indices to characterize arthropod community structure. 943 https://msra.online/index.php/Journal/about Volume 3, Issue 4 (2025) Statistical Analysis All data were analyzed using R (version 4.4.2) and SPSS (version 28). Two-way ANOVA was used to evaluate treatment and seasonal effects on soil fertility, pest suppression, and crop productivity. Mean comparisons were conducted using Tukey’s HSD test (p < 0.05). Pearson correlation coefficients were calculated to assess relationships among soil biological attributes, pest control efficiency, and yield. Principal Component Analysis (PCA) was applied to identify dominant ecological factors contributing to system sustainability. Data were tested for normality and homogeneity of variance using Shapiro–Wilk and Levene’s tests, respectively. Ethical and Environmental Considerations All experimental procedures adhered to institutional ethical and environmental research guidelines. The release of beneficial insects was conducted under the supervision of local entomological authorities to ensure ecological compatibility. Earthworms used in this study were locally adapted species to prevent invasive risks. No genetically modified organisms (GMOs) or synthetic agrochemicals were introduced during experimentation. Field residues and organic wastes were composted and reused to maintain sustainability and minimize environmental footprint. Results Effects of Earthworms on Soil Health and Fertility The inoculation of Eisenia fetida markedly improved soil physicochemical and biological properties compared with the control (Table 1). Organic carbon, total nitrogen, and available phosphorus were significantly higher in the earthworm-treated plots, indicating enhanced nutrient cycling and microbial activity. Organic carbon increased by 28.7%, total nitrogen by 22.5%, and available phosphorus by 18.9% relative to control plots. The microbial biomass carbon (MBC) also showed a considerable rise (315.4 ± 12.3 mg kg⁻¹), demonstrating elevated microbial turnover. Furthermore, enzymatic activities such as dehydrogenase and phosphatase increased by 35% and 31%, respectively, signifying improved biochemical functioning of the soil ecosystem. Soil pH remained near neutral (7.3–7.5), indicating that earthworm activity promoted biological fertility without altering soil acidity. The collective improvement in soil fertility parameters is visually represented in Figure 1, which illustrates the enhancement of organic carbon, nitrogen, and phosphorus concentrations under biotic treatments. Table 1: Changes in Soil Physicochemical and Biological Properties Under Different Treatments Parameter Control Earthworm Treatment Beneficial Insects LSD (0.05) Organic Carbon (%) 1.21 ± 0.05 1.56 ± 0.04 1.28 ± 0.06 0.08 Total Nitrogen (%) 0.09 ± 0.01 0.11 ± 0.01 0.10 ± 0.01 0.01 Available P (mg kg⁻¹) 23.4 ± 1.2 27.8 ± 1.5 24.9 ± 1.4 1.3 MBC (mg kg⁻¹) 258.9 ± 10.4 315.4 ± 12.3 271.2 ± 11.6 13.5 Dehydrogenase (µg TPF g⁻¹ h⁻¹) 12.4 ± 0.8 16.8 ± 1.0 13.5 ± 0.7 1.1 944 https://msra.online/index.php/Journal/about Volume 3, Issue 4 (2025) Figure 1: Effects of earthworms and beneficial insects on soil fertility. Influence on Pest Suppression and Natural Enemy Dynamics Plots augmented with beneficial insects—Coccinella septempunctata and Chrysoperla carnea—exhibited a substantial reduction in pest populations compared with control plots. Aphid and whitefly densities decreased by 72% and 65%, respectively, while predator populations increased nearly threefold (Table 2). Biological control efficiency (BCE) reached 78.5%, reflecting the successful predation of aphids and other soft-bodied insects. Shannon–Wiener and Simpson’s indices also indicated higher species diversity and ecological stability under beneficial insect treatments. These patterns are depicted in Figure 2, where pest density declined sharply with corresponding increases in predator abundance. Table 2: Mean Pest and Predator Populations and Biological Control Efficiency Under Different Treatments Treatment Aphid Density (no./10 plants) Whitefly Density (no./10 plants) Predator Density (no./plot) BCE (%) Shannon–Wiener Index (H′) Control 184.5 ± 9.6 136.2 ± 8.4 8.4 ± 0.8 — 1.42 Earthworm 161.3 ± 8.8 118.9 ± 7.1 10.6 ± 1.0 30.1 1.68 Beneficial Insects 51.2 ± 5.7 47.9 ± 4.6 25.7 ± 2.2 78.5 2.11 945 https://msra.online/index.php/Journal/about Volume 3, Issue 4 (2025) Figure 2: Pest suppression and predator abundance across treatments. Effects on Plant Growth, Yield, and Fruit Quality Biotic treatments substantially improved plant growth and productivity (Table 3). Earthworm-treated plots produced the tallest plants (87.3 ± 2.1 cm) and the highest leaf area index (3.84 ± 0.15), indicating superior vegetative vigor. Beneficial insect treatments led to a marked decline in pest-induced leaf damage and a 26.7% increase in fruit yield compared with the control. The combined effects of earthworms and insects resulted in a 34.8% enhancement in total fruit biomass. Fruit quality parameters—vitamin C and total soluble solids (TSS)—also increased under both treatments, suggesting improved nutritional and market value of produce. These patterns are visualized in Figure 3, illustrating the superior yield and quality metrics associated with biological treatments. Table 3: Plant Growth, Yield, and Fruit Quality Under Different Treatments Parameter Control Earthworm Treatment Beneficial Insects LSD (0.05) Plant Height (cm) 68.4 ± 2.5 87.3 ± 2.1 79.6 ± 2.3 3.6 Leaf Area Index 2.95 ± 0.12 3.84 ± 0.15 3.52 ± 0.14 0.20 Fruit Yield (kg/plot) 4.92 ± 0.30 6.61 ± 0.35 6.23 ± 0.28 0.42 Vitamin C (mg/100g) 15.6 ± 0.8 19.3 ± 0.7 18.1 ± 0.9 1.0 TSS (°Brix) 5.4 ± 0.2 6.2 ± 0.3 6.4 ± 0.2 0.3 946 https://msra.online/index.php/Journal/about Volume 3, Issue 4 (2025) Figure 3: Effect of treatments on yield and fruit quality. Relationship Among Soil Health, Pest Regulation, and Yield Correlation analysis revealed strong positive associations between soil organic carbon and fruit yield (r = 0.86, p < 0.01), and between microbial biomass carbon and vitamin C content (r = 0.73, p < 0.05). These results indicate that soil biological enrichment contributes directly to improved crop performance. The relationship between soil carbon content and yield is depicted in Figure 4, demonstrating that biologically enriched soils produced higher yields. Principal Component Analysis (PCA) explained 68% of the total variance, with PC1 (soil nutrient status) and PC2 (biological control) serving as dominant contributors to system sustainability. 947 https://msra.online/index.php/Journal/about Volume 3, Issue 4 (2025) Figure 4: Correlation between soil organic carbon and crop yield. Summary of Findings The results confirm that integrating earthworms and beneficial insects substantially enhances soil fertility, pest regulation, and crop productivity. Earthworms improved nutrient cycling and microbial activity, while beneficial insects provided sustainable pest suppression. Together, these biological agents fostered a more resilient agroecosystem with higher yield quality and ecological stability. Hence, adopting such biotic interventions presents a practical pathway toward ecologically sound and resource-efficient sustainable agriculture. Discussion The results of this study demonstrated the substantial contributions of earthworms and beneficial insects to agroecosystem performance in terms of soil fertility, biological control, and crop yield. The increased levels of soil organic carbon, nitrogen, and phosphorus in the earthworm-treated plots confirmed previous research, suggesting that earthworms regulate nutrient cycling and soil structure formation (Fonte et al., 2023). The higher microbial biomass carbon and enzymatic activity in our study further confirmed that earthworm activity enhanced microbial decomposition and nutrient mineralization, which is like the findings of Ahmed and AlMutairi (2022). Similarly, Ganapathy et al. (2025) reported that the bioactive components of earthworm secretions and vermicompost improved the enzymatic profile in soils, which is consistent with our findings. The enhancing effect of soil structure and aeration may also be caused by earthworm burrowing, as Li et al. (2024) stated that the presence of macropores formed by earthworms increased soil aeration and C sequestration. The natural enemies Coccinella septempunctata and Chrysoperla carnea played important roles in pest control, whereas introduced predators significantly decreased pest populations and increased the diversity of native species. The reduction in aphid and whitefly populations observed in our investigation, as reported by Krishnamoorthi et al. (2024), agreed with a study that found that predatory insects were more beneficial than ants in controlling pests in organic systems. The biological control efficiency found in our study was comparable to that described by Ansabayeva et al. (2025), where closely related predators resulted in more than 70% suppression of aphid populations. Similarly, the improved predator–prey ratios and biodiversity indices observed in our study corroborated findings from (Jeffers & Chong, 2021), which also demonstrated that combining several beneficial species can enhance pest suppression efficiency. The present findings were also in harmony with the concepts reported by Zhou et al. (2024) as integrated pest management, where natural enemies played a vital role in minimizing chemical application and upholding ecological stability. Parameters related to plant growth, yield, and fruit quality were also significantly improved by biological treatments. The 34.8 percent yield increment we observed was in line with the worldwide estimate of Fonte et al. (2023), which suggested that earthworm involvement in improving crop yield is about 25%. The increase in vitamin C and total soluble solids (TSS) also coincided with the results of Ganapathy et al. (2025), who showed that humic substances from vermicompost enhanced antioxidant metabolism and improved fruit quality. Likewise, decreased pest pressure due to beneficial insects might lead to increased photosynthetic efficiency and resource investment. This is like findings in Ryalls et al. (2024), who observed that IPM practices improved both yield and quality. The significant positive correlation between soil carbon and yield (r = 0.86) found in this study similarly justified the relationships discovered by Ahmed and Al-Mutairi (2022) and Li et al. (2024), who showed that the percentage of soil organic matter was one of the main factors influencing crop yield in biologically treated systems. The joint action of earthworms and beneficial insects exerted a synergistic effect on soil fertility improvement, pest control, and crop growth. These results corroborate the principles of sustainable intensification when biological substitutes are added or replace external chemical inputs. The combined use of soil-borne organisms with aerially released biocontrol agents is an effective technique for sustainable control and 948 https://msra.online/index.php/Journal/about Volume 3, Issue 4 (2025) enhancing system productivity. These findings were consistent with a recent ecological model hypothesized by Ganapathy et al. (2025) and Li et al. (2024), highlighting the potential role of biodiversity-based strategies in enhancing the resilience, sustainability, and productivity of agroecosystems in a new environmental context. Conclusion Earthworms (Eisenia fetida) and natural enemies (Coccinella septempunctata and Chrysoperla carnea) significantly improved the sustainability and productivity of tomato-based agroecosystems. Earthworm inoculation, which enhances soil fertility, nutrient availability, and biological activity, may have long-term effects by increasing organic carbon, nitrogen (N), phosphorus (P), microbial biomass, and enzymatic activities. Simultaneously, the introduction of natural enemies substantially reduced aphid and whitefly abundance, achieving an important ratio of predators by enhancing the effectiveness of both biological control methods. These ecological interactions have led to remarkable increases in plant growth, yield, and fruit quality, implying the synergistic role of belowand above-ground biodiversity in sustainable crop management. The results support the notion that both soil engineers and natural enemies work together to enhance ecosystem resilience and reduce reliance on synthetic fertilizers and pesticides. The positive relationships between soil biological indicators and crops highlight the ecological and economic benefits of introducing a biotic-based strategy. Thus, combining earthworm-driven soil restoration with pest control by beneficial insects is a promising, cost-effective, and eco-friendly strategy for crop production. Long-term field validation, species interaction modeling, and scalability in heterogeneous agro-ecological zones are needed to refine the integrated application of these biological assets for resilient and regenerative agriculture. Funding Not applicable References Ahmed, N., & Al-Mutairi, K. A. (2022). Earthworms effect on microbial population and soil fertility as well as their interaction with agriculture practices. Sustainability, 14(13), 7803. Ansabayeva, A., Makhambetov, M., Rebouh, N. Y., Abdelkader, M., Saudy, H. S., Hassan, K. M., Nasser, M. A., Ali, M. A., & Ebrahim, M. (2025). Plant growth-promoting microbes for resilient farming systems: mitigating environmental stressors and boosting crops productivity—A review. Horticulturae, 11(3), 260. Arnold, S. E., Elisante, F., Mkenda, P. A., Tembo, Y. L., Ndakidemi, P. A., Gurr, G. M., Darbyshire, I. A., Belmain, S. R., & Stevenson, P. C. (2021). Beneficial insects are associated with botanically rich margins with trees on small farms. Scientific Reports, 11(1), 15190. Bashir, H., Ammar, A., Bashir, S., Hassan, A., & Rashid, M. (2023). Insects as Allies: The Role of Beneficial Insects in Sustainable Agriculture. Trends in Animal and Plant Sciences, 23(2), 17-24. Datta, A., Sankaranarayanan, S., & Bhatia, U. (2025). Temporally staggered cropping co-benefits beneficial insects and pest control globally. arXiv preprint arXiv:2509.16284. Fonte, S. J., Hsieh, M., & Mueller, N. D. (2023). Earthworms contribute significantly to global food production. Nature communications, 14(1), 5713. Ganapathy, N. R. V., Elango, A. C., Balaji, G., Sankaranarayanan, M., & Sharma, M. (2025). A comprehensive review of earthworm-derived vermiproducts and their role in sustainable agriculture. Discover Applied Sciences, 7(9), 995. Gill, K. A. (2013). Development of best-practices for conserving beneficial insects within Iowa's agricultural landscape Iowa State University].