Challenges and constraints in implementing integrated pest management for pepper stem borer (Lophobaris piperis Marshall) among Indonesian smallholder farmers: a critical review

Abstract

This review examines the challenges that prevent the adoption of integrated pest management in black pepper (Piper nigrum L.) cultivation in Indonesia, emphasizing the impact of Lophobaris piperis Marshall (Coleoptera: Curculionidae), a critical stem borer pest in Southeast Asian black pepper-producing countries. The recommended integrated pest management strategies involve employing pepper varieties tolerant to L. pipperis, routine pest population monitoring, mechanical controls, adherence to adequate agricultural practices, and environmentally responsible pesticide management. The review encompasses technical and nontechnical aspects, addressing challenges like farmer skills, knowledge, government support, and market prices. We identified obstacles and opportunities in implementing sustainable pest management strategies, especially in the largest black pepper plantations in Indonesia. This comprehensive review provides valuable insights for enhancing the effectiveness and sustainability of black pepper pest management, ultimately benefiting smallholder farmers’ livelihoods and the sustainability of their pepper farming enterprises.

Case Studies

Black pepper (Piper nigrum L.) (Family: Piperaceae), a key spice crop, is primarily cultivated in tropical regions (Salehi et al. 2019, Nair 2020). The leading producing countries of black pepper worldwide are Vietnam, Indonesia, India, and Brazil, in descending order of production volume (Azahari et al. 2021). Indonesia claimed the largest land area dedicated to black pepper cultivation from 2014 to 2018. However, the extent of black pepper cultivation in Indonesia has remained stagnant since 2014, whereas Vietnam and Brazil have seen an increase in acreage. This crop continues to play a crucial role in the Indonesian economy and is ranked as the leading exported spice commodity (Siswanto et al. 2021). Black pepper cultivation in Indonesia is widespread, covering all provinces, with main production centers including Bangka Belitung, East Kalimantan, Lampung, South Sulawesi, Southeast Sulawesi, West Kalimantan, and South Sumatra (DGEC 2021).

Despite having the largest cultivation area in the world at 193,854 hectares, Indonesian black pepper production in 2022 was only 89.3 tons (DGEC 2023), equivalent to only 23% when compared to the Vietnamese production, which had a 58% contribution to global markets (Azahari et al. 2021, Siswanto et al. 2021). The low Indonesian productivity of pepper was attributed to technical and nontechnical factors, including the farming systems in place and pest and disease issues (Karmawati et al. 2020).

However, successful integrated pest management (IPM) implementation faces numerous challenges, particularly in smallholder farming systems of developing countries. These challenges include limited access to knowledge and technical resources, inadequate extension services, socioeconomic constraints, and the complexity of IPM practices compared to conventional pest control methods (Deguine et al. 2021, Eryanto et al. 2023). Additionally, the adoption of IPM practices is influenced by farmers’ risk perception, educational background, and the availability of support systems (Kyire et al. 2023).

IPM has evolved as a sustainable approach to pest control that integrates multiple tactics while minimizing environmental impacts and promoting ecological balance. Modern IPM emphasizes prevention, monitoring, and control decisions based on economic thresholds, combining biological, cultural, physical, and chemical methods in a compatible manner. This approach aims to reduce pesticide dependency while maintaining crop productivity and farmer profitability. Recent advances in IPM have incorporated digital technologies, predictive modeling, and climate-smart strategies to enhance decision-making and implementation effectiveness (Ashfaq et al. 2024, Kariyanna and Sowjanya 2024, Mahlein et al. 2024).

In Indonesian pepper cultivation, these challenges are particularly evident. Pepper plantations are owned by smallholder farmers, who often employ nonsuperior seed varieties and inconsistent cultivation practices that do not adhere to established operational standards (Pitono 2019). The unstable price of pepper significantly impacts farm management, leading to suboptimal outcomes during periods of low prices and improved practices when prices are high.

Pepper production in Indonesia faces significant challenges due to insect pests and plant diseases (Amorita et al. 2021). Three major pests, namely the pepper stem borer Lophobaris piperis Marsh (Coleoptera: Curculionidae), pepper bug, Dasynus piperis China (Hemiptera: Coreidae), and blossom bug, Diconocoris hewetti Distant (Hemiptera: Tingidae), along with 3 major diseases, Phytophthora foot rot, yellows disease caused by nematodes Radopholus similis Thorne and Meloidogyne incognita Kofoid and White 1919; Chitwood 1949, and stunted growth disease caused by Cucumber Mosaic Virus. These biological threats adversely impact the entire black pepper industry, consistently posing significant problems for farmers across the country (Manohara et al. 2005, Laba and Trisawa 2006, Bande et al. 2015, Ropalia et al. 2022). At the same time, the distribution of major insect pests was influenced by climatic and geographic conditions, particularly D. hewetti and D. piperis (Laba and Trisawa 2006), while L. piperis was found in all pepper-producing provinces (Soetopo 2012a). Among these, the pepper stem borer L. piperis stands as a major pest found in all pepper-producing provinces (Soetopo 2012a). Production losses due to pepper stem borers in Lampung have reached significant levels, making it a crucial insect pest in that region over the last 50 years (CADI 2021, DGEC 2021). The paradigm has shifted away from conventional control which relying solely on chemical insecticides practices toward IPM, given the concerns related to export residue limits for exported commodities, reduced yields, and declining income for pepper farmers.

IPM has evolved significantly in recent years, moving beyond its traditional definition to encompass more holistic and sustainable approaches. Modern IPM emphasizes prevention, monitoring, and control decisions based on economic thresholds, while integrating ecological principles and technological innovations. The contemporary IPM framework incorporates multiple components: prevention through crop management and habitat manipulation, monitoring using advanced technologies, biological control enhancement, and judicious use of chemical controls when necessary (Dara 2019, Kennedy and Lekshmi 2022).

Recent developments in IPM have introduced several innovative concepts and strategies. These include: (i) digital agriculture integration, utilizing artificial intelligence, remote sensing, and precision agriculture tools for better pest monitoring and decision-making; (ii) climate-smart IPM approaches that consider changing weather patterns and their impact on pest dynamics; (iii) enhanced biological control strategies through conservation and augmentation of natural enemies; and (iv) area-wide management approaches that coordinate pest control efforts across landscapes rather than individual fields (Samanta et al. 2024).

The success of IPM implementation depends heavily on understanding and addressing socio-ecological contexts. Barrera (2020) emphasizes that effective IPM programs must consider not only the biological and technological aspects but also the social, economic, and cultural dimensions of farming communities. This includes farmers’ traditional knowledge, market demands, and local resource availability. Furthermore, successful IPM adoption requires strong institutional support, including research, extension services, and policy frameworks that encourage sustainable pest management practices (Massimi et al. 2022).

However, implementing these modern IPM concepts faces numerous challenges, particularly in smallholder farming systems of developing countries. These challenges include limited access to knowledge and resources, inadequate extension services, socioeconomic constraints, and the complexity of IPM practices compared to conventional pest control methods. (Khan et al. 2021, Tambo and Matimelo 2021). Additionally, the adoption of IPM practices is influenced by farmers’ risk perception, educational background, and the availability of support systems (Sekabira et al. 2022). However, implementing IPM for L. piperis control presents unique challenges in the context of smallholder farming systems, requiring careful consideration of local conditions, farmer capabilities, and available resources.

This review critically examines the challenges and constraints in implementing IPM for L. piperis control among Indonesian smallholder pepper farmers. We analyze current technologies and strategies, assess their practical implications, and provide recommendations for improving IPM adoption in smallholder farming contexts. The findings aim to support more effective pepper stem borer management strategies applicable to Indonesia and other pepper-producing countries.

Lophobaris piperis in Indonesian Agroecosystems

Among the 3 critical insect pests of black pepper in Indonesia, L. piperis is the most important pest influencing pepper production. This weevil causes yield losses and plant death, while the insect has already been distributed in all black pepper-producing Indonesian provinces.

Biology of L. piperis

The weevil undergoes complete metamorphosis, encompassing 4 stages: egg, larva, pupa, and adult. The adult female lays eggs in the stems of the pepper plant. These eggs are whitish to yellowish, measuring 0.45 to 0.75 mm in length and 0.51 to 0.71 mm in width (Laba and Trisawa 2006). After egg eclosion, the larva immediately burrows into the pepper stem. Larval infestation is marked by small holes in the stem and yellowing around the entry point (Fig.1). These entry points later turn dark brown (Fig. 2). The feeding and tunneling activities of larvae in the stem destroy internal tissues, causing symptoms such as wilting, breakage, and even stem death (Fig. 3). Infestation can lead to plant death when it begins at the base of the stem. The adults, can also harm fruit as they infesting pepper fruit by boring from the tip (Fig. 4) (Deciyanto et al. 1986). The pupal stage lasts 7 to 11 d, once the pupa transitions into an adult (imago), the adult emerges from the tree trunk. Subsequently, adults emerge from the stem, initiating reproduction. Adult L. piperis (Fig. 5) emerges from the stem and causes injury to the pepper by feeding on shoots, fruit, and flowers. The bite marks left by the adults turn black and decay over time. The damage caused by adults is not as severe as that inflicted by larvae. The entire life cycle, from egg to adult, spans 45 to 60 d (Laba and Trisawa 2006).

Natural Control of L. piperis

The density and dynamics of L. piperis populations in the field are influenced by the availability of pepper fruit as the primary food source for adults and by seasonal factors. Larval populations of L. piperis were higher during the rainy than during the dry season. The generation of L. piperis overlapped in all seasons in tropical Indonesian regions, with distinct rainy (November to April) and dry (May to October) seasons (Suprapto and Martono 1989). However, high infestations occurred in the rainy season, and the insect population was low in the dry season (Soetopo 2012a). Abiotic factors, such as temperature and humidity, also significantly affect the life of L. piperis. However, a comprehensive understanding of the impact of environmental factors on pepper stem borers in Indonesian plantations is currently lacking, except that the insect exhibits an aversion to high-intensity sunlight (Laba and Trisawa 2006).

The population dynamics of pepper stem borers were subject to fluctuations driven by biotic and abiotic factors. Biotic factors affecting L. piperis include predators, parasitoids, and entomopathogens. Various common predators were found in pepper plantations, including spiders, wasps, predatory beetles (rove beetles, ground beetles, and Coccinellid), dragonflies, ants, lady beetles, and robber flies (Hindayana et al. 2002). However, the impact of these generalist predators on L. piperis populations requires further investigation.

Parasitoids also play a crucial role in the population regulation of L. piperis. The parasitoid species such as Spathius piperis Wilkinson (Hymenoptera: Braconidae), Euderus sp. (Hymenoptera: Eulophidae), Dinarmus coimbatorensis Ferriere (Hymenoptera: Microgasteridae), and Eupelmus curculionis Ferriere (Hymenoptera: Eupelmidae) have been recorded as parasitoids of pepper stem borer larvae (Hindayana et al. 2002). Natural parasitism rates by larval endoparasitoid S. piperis reached 25% (Kalshoven 1981). The parasitism rate of L. piperis by S. piperis ranged from 25% to 50%, particularly when crops like Arachis pintoi Karp & Greg (Family Fabaceae) were also present in pepper plantations from Natar, Lampung (Indonesia) between 1986 and 1987 (Suprapto and Martono 1989).

Entomopathogens Beauveria spp. have also been identified as potential biological control agents for pepper stem borers (Soetopo 2012b). Laboratory examination showed that the dosage of spores B. bassiana 10⁸ conidia could cause 50% mortality in L. piperis (Suprapto et al. 1991). At the same time, Deciyanto and Trisawa (1999) observed that the dosage of a different isolate of B. bassiana conidia 4.5 × 10⁵ within 28 d could cause 89.67% mortality in L. piperis adults. Nevertheless, their intensive use for managing L. piperis in pepper crops is still limited and has not been thoroughly documented.

Development and Implementation of IPM for Pepper Stem Borers

The Indonesian government, along with researchers and extension professionals, has proactively addressed challenges in the burgeoning pepper industry through IPM implementation. The proper implementation strategies for IPM programs have been outlined by Trivedi and Ahuja (2011). This approach, aligned with the comprehensive ecological strategy for pest and disease control, was mandated by the government through Presidential Instruction No. 3/1986 and National Regulation No. 12/1992. The IPM concepts are designed to promote a focus on environmental quality and sustainable development. The implementation of IPM is specified in National Regulation No. 22/2019 on agricultural sustainable cultivation systems and No. 39/2014 on crop estates, including black pepper plantations.

The objectives of IPM for black pepper were 4-fold: (i) to enhance the knowledge and skills of farmers in applying IPM through experiential learning in the field; (ii) to test IPM methods within the black pepper farming system and integrate them into training activities; (iii) to establish ongoing education on crop protection for farmers at the provincial to regional levels; and (iv) to establish a policy and legislative framework supporting the long-term success of the program. The program concept incorporated participatory and empowering approaches, emphasizing participative, collaborative, flexible, and network-based program design. Consequently, the program consisted of 3 main components: (i) the development of IPM technology, (ii) the promotion and sharing of IPM practices, and (iii) the implementation of farmer field schools (FFS).

In the next section, we explored the implementation of IPM for black pepper plantations adopted by farmers in growing areas. This approach included technical pest management methods in black pepper cultivation by smallholder farmers and the nontechnical factors that affected IPM implementation. Furthermore, we explored the challenges and obstacles encountered during its implementation.

Implementation of IPM in Black Pepper Plantations of Smallholder Farmers

The development of IPM in black pepper cultivation has been the focal point of research in various black pepper farming regions, including Lampung, the largest black pepper plantation in Indonesia. Research findings have guided the effective and sustainable management of black pepper pests. Recommended black pepper pest management strategies have evolved to include various effective approaches. Recommended IPM of black pepper plantation for L. piperis included well-adopted standard term of IPM tactics. Multiple, compatible, complementary tactics are researched, adapted and then implemented at grower level in IPM and decision-making strategies.

The component control techniques included: (i) using pepper varieties tolerant to L. piperis, (ii) implementing mechanical control by removing plant parts displaying signs of L. piperis infestation (after removal, plant material should be either burned or buried at least 30 cm deep to promote decomposition and prevent larval survival), (iii) employing good agricultural practices, such as using living standards (living trees as support systems for pepper vines to climb and grow), optimal crop maintenance, balanced fertilization as optimally required by the plant, the use of organic fertilizers, planting cover crops, and integrating black pepper with other crops as intercrops, (iv) implementing biological control through the conservation of natural enemies, especially the use of entomopathogens, and (v) managing pest populations with environmentally responsible pesticides.

Superior Varieties Use

The initial and crucial step in pest management was the selection of black pepper superior varieties which are tolerant to L. piperis infestations. As of 2021, the Indonesian Ministry of Agriculture has released 10 superior black pepper varieties, including Petaling 1, Petaling 2, Natar 1, Natar 2, Bengkayang, and others. Varieties such as Natar 1 and Natar 2 have demonstrated tolerance to L. piperis infestations with suppressed the L. pipperis infestation up to 15% (Deciyanto et al. 1984, Suprapto 1988). These varieties have already been examined for use in Malaysia to control the infestation of L. piperis in Malaysian black pepper plantations (Anuar 1993).

Nevertheless, the distribution and adoption of these tolerant varieties in smallholder black pepper plantations remain limited and poorly documented. This lack of information hinders their contribution to black pepper pest management systems. The adoption was hampered not by farmers’ lack of understanding of the tolerant varieties’ benefits, but by their reluctance to replace existing plants due to high replacement costs and the waiting period before new plants become productive. Efforts to increase the dissemination of these varieties were being conducted through mass extension programs and FFS (Wahyudi and Hasibuan 2011). However, the effectiveness of these educational programs regarding tolerant varieties has not been evaluated.

Mechanical Control

Mechanical control methods exploit the natural behavioral responses of L. piperis to manage their populations. Adult L. piperis are highly sensitive to vibrations and exhibit a distinct defensive response when disturbed: they immediately release their hold and drop from the plant. This behavior can be effectively utilized through plant shaking, a simple yet environmentally friendly control method. When stems are shaken, adult borers instinctively drop from the canopy, allowing for their collection in containers placed beneath the plants. These collection containers are filled with soapy water solution, which reduces surface tension and causes fallen insects to sink immediately, preventing their escape. Building on the plant shaking method, farmers in Vietnam and India have enhanced their capture efficiency by incorporating nets and adhesive traps beneath the pepper plants. Despite the proven effectiveness of these mechanical control techniques, their adoption remains limited among smallholder pepper farmers. Consequently, many smallholder plantations continue to experience significant L. piperis infestations, primarily due to inconsistent implementation of these control methods.

Cover Crops Growing

Implementing good agricultural practices for optimal and healthy black pepper growth is essential for pest management. Optimal plant maintenance, balanced fertilization based on plant requirements (preferably organic fertilizers), planting cover crops, and intercropping with other plants are recommended cultivation techniques (Pitono 2019, Rusiva and Suherman 2019, Rismayani et al. 2020, Rohimatun et al. 2022). Cover crops such as A. pintoi Krapov and WC Gregori (Leguminosae) could enhance the diversity of insects, including pests and natural enemies, in black pepper agroecosystems (Trisawa et al. 2005).

The use of A. pintoi as a cover crop increased both species diversity and population of arthropods: phytophagous insects by 48%, omnivorous insects by 12%, and natural enemies by 38% (Trisawa et al. 2004). The parasitism rate of L. piperis larvae by S. piperis Wilkinson (Hymenoptera: Braconidae) was higher (6% to 28%) in plots with A. pintoi compared to plots without A. pintoi or plots with complete weeding (3% to 9%) (Trisawa et al. 2004). Interestingly, plots where weeds were allowed to grow naturally showed arthropod diversity comparable to plots with A. pintoi. Beyond enhancing arthropod diversity, A. pintoi, being a leguminous plant, also improves soil fertility through nitrogen fixation by rhizobium bacteria (Isnan and Kartika 2016).

Despite scientific evidence supporting the benefits of A. pintoi as a cover crop, its adoption among pepper farmers in Indonesia remains low. Farmers are reluctant to implement this practice due to the additional costs and complex maintenance requirements. Instead, they prefer intercropping with citronella grass plants between pepper stands, which provides additional income but does not offer the same level of arthropod biodiversity enhancement (Fig. 6). Furthermore, farmers have reported concerns about increased snake presence in the shaded, humid, and dense vegetation created by A. pintoi (Fig. 7). This case illustrates a common challenge in agricultural innovation adoption, where scientifically proven methods may face practical implementation barriers due to economic constraints, management complexity, and farmers’ safety concerns. To bridge this gap between scientific recommendation and farmer adoption, there is a need to develop more farmer-friendly cover crop management practices or explore alternative ground cover options that can balance ecological benefits with practical feasibility and farmer acceptance.

The Use of Living Standards—Climbing Pole

A climbing pole or standard serves as an upright pillar to which the roots extending from each node of the climbing tendrils (orthotrop) are attached. The terms nonliving standard and living standard refer to two categories of standards or poles. Dead stems of ironwood (Acacia oraria F.Muell.) (Family Leguminosae), mendaru (Urandra corniculata Beccari) (Family: Icacinaceae), pelawan (Tristaniopsis maingayi (Duthie) Peter G.Wilson & J.T.Waterh.) (Family: Myrtaceae), and melangir (Shorea balangeran (Korth.) Burck) (Family: Dipterocarpaceae) are commonly used as nonliving standards (Zaubin and Yufdi 1996) (Fig. 8A). This type of nonliving standard is extensively implemented in Bangka, East Kalimantan, and West Kalimantan (Daras and Wahid 2000). In Lampung, the prevailing living standards consist of dadap (Erythrina fusca), kapok (Ceiba pentandra), and gamal (Gliricidia sp.) trees (Daras and Wahid 2000) (Fig. 8B).

In black pepper cultivation, living standards have been recommended, especially for increasing the efficiency of black pepper cultivation. In Lampung, common living standards include Gliricidia maculata (Kunth) Steud (Fabaceae), and E. fusca Lour. (Fabaceae), C. petandra (L.) Gaertn (Fabaceae), Erythrina lihosperma (Hassk.) Merr. (Fabaceae), and Erythrina indica L. (Fabaceae) (Daras 2015). This method involves pruning to control sunlight for black pepper plants, creating a less favorable environment for L. piperis than nonliving standards.

Living standards enhance the probability of successful pepper plant growth and prolong the lifespan of the plant by reducing stress, especially in the dry season, since the plant requires around 50% to 75% sunlight (Syakir 2018). Despite the positive effects of living standards in reducing L. piperis infestations, this method has not been widely adopted by farmers due to their limited understanding of its functionality and concerns about increased maintenance demands, which were seen as a source of additional input costs (Syam 2004).

The Use of Biological Control Agents

Among biological control agents, the entomopathogenic fungus Beauveria bassiana has demonstrated potential in controlling L. piperis. Laboratory studies showed that bioinsecticide formulations containing B. bassiana spore suspensions at 20 g/L could achieve a 20% mortality rate when applied to the L. piperis adults (Wiratno et al. 2020). However, despite this promising efficacy, the adoption of biological control methods among pepper farmers in Indonesia remains low. Several factors contribute to this limited implementation, including farmers’ restricted access to commercial bioinsecticide formulations, their skepticism about the effectiveness of biological control compared to conventional insecticides, and their lack of technical knowledge in proper application methods. Additionally, the relatively slow action of biological control agents compared to chemical insecticides often influences farmers’ perception and acceptance of these sustainable control methods.

The Use of Botanical Pesticides

IPM emphasizes the combination of several complementary tactics, including both chemical and nonchemical methods, through a systematic approach that focuses on long-term prevention and management of pests and their damage while minimizing risks to human health and the environment. While nonchemical options are important components, IPM does not exclude the judicious use of pesticides when necessary. Botanical pesticides, which have the potential to be integrated into IPM, consist of phytochemical-based pesticides that influence the physiology and behavior of insects. Extracts of Pyrethrum flowers with 25 and 50 μg/ml concentrations caused 87% and 100% mortality rates in L. piperis beetles, respectively, within 24 h after application (Wiratno 2008). These pesticides have not been widely adopted in areas with high L. piperis infestations despite the high effectiveness of botanical insecticides against L. piperis. The lack of feedback from farmers, limited access to botanical insecticides, and concerns about their use have contributed to this situation. Furthermore, the technology readiness level for botanical insecticides was still relatively low, and these products have not reached the stage of widespread production and distribution.

Pest Population Monitoring

Regular monitoring of L. piperis populations is essential for implementing effective control measures. The action threshold for L. piperis has been established at 3 adult weevils per plant, indicating the critical point at which control measures must be initiated to prevent significant damage to pepper plants (Deciyanto et al. 1986). This action threshold provides farmers with a clear, practical decision-making tool regardless of pepper market prices. When the weevil population reaches this threshold, immediate control actions are necessary because female adults can quickly lay eggs in the pepper stems, leading to internal damage by developing larvae. However, monitoring in smallholder pepper plantations has been inadequate, leading to suboptimal pest control strategies. A systematic monitoring approach combining multiple detection methods is crucial for effective pest management, enabling farmers to take timely action before the pest population causes substantial vine damage.

Extension workers play a vital role in assisting farmers with pest monitoring, particularly during the rainy season (October to April) when L. piperis populations typically peak (Soetopo 2005). Key monitoring techniques include: (i) visual inspection of stems for entry holes, frass, and wilting symptoms, (ii) plant shaking in the early morning to count fallen adult weevils on a collection sheet placed beneath the vine, and (iii) systematic sampling of multiple plants within the plantation to assess infestation levels. Early detection is critical, as a single infested main stem can result in up to 43% production loss per plant. Extension services should prioritize training farmers to recognize early infestation signs, such as small holes in stems, sawdust-like frass around entry points, and wilting of young shoots. Regular weekly monitoring during peak seasons and biweekly during off-peak seasons is recommended to maintain effective pest surveillance. Additionally, record-keeping of monitoring data helps track population trends and evaluate the effectiveness of control measures over time.

Development of an Expert System Strategy

Expert systems have demonstrated significant potential for supporting IPM implementation in black pepper plantations. These systems were developed through interaction matrices to serve as decision-making tools, facilitating collaboration among stakeholders including policymakers, scientists, extension workers, and farmers. The systems integrate multiple variables crucial for IPM decision-making, such as insect life stages, crop phenology, cultivation systems, weather conditions, and timing of control actions. They also incorporate various control components including mechanical, physiological, cultural, biological (parasitoids and entomopathogens), host plant resistance, and chemical control strategies (Soetopo 2005). However, the expert system for pepper stem borer management has not achieved its full potential due to gaps in component control information, limiting its effectiveness as a decision support tool for stakeholders in the field.

Despite their promise in enhancing pest control effectiveness, the implementation of expert systems for managing pepper stem borers in Indonesia faces significant challenges. Key limitations include insufficient integration of field-based knowledge, inadequate updating of control recommendations, and technical barriers in system deployment. Moreover, smallholder farmers often have limited access to digital technology and lack training in system utilization. To address these challenges and optimize expert system implementation, several strategic interventions are necessary: (i) developing user-friendly interfaces specifically designed for farmer needs, (ii) regularly updating the knowledge base with local farming practices and current research findings, (iii) strengthening the role of extension workers in providing technical support and training, (iv) ensuring system accessibility through mobile platforms, and (v) establishing user networks for experience sharing and information exchange. Additionally, the system should be capable of accommodating local conditions and farmer practices while maintaining scientific accuracy in its recommendations. This comprehensive approach would enhance the practical value of expert systems as decision support tools for pepper stem borer management at the farmer level.

Promotion and Sharing of IPM and FFS

The Indonesian government initiated a program related to IPM implementation on black pepper to empower black pepper farmers and field workers from 1998 to 2005. This program included pepper stem borers and comprised: (i) FFS for 15,000 farmers in the provinces like Bangka and Lampung, in the producing center of black pepper, (ii) 5,000 field workers, (iii) 20 training for trainers, (iv) training for farmer to farmer, and (v) supportive policies (DGEC 2005). The program is still running up to date in provinces producing black pepper, such as Bangka Belitung, West Kalimantan, and East Kalimantan (DGEC 2023). However, there was no further evaluation of the implementation at the farmer level.

Constraints and Challenges to IPM Implementation

The implementation of modern IPM approaches for managing L. piperis in Indonesian pepper agroecosystems faces multiple interconnected challenges that span economic, social, technical, and institutional dimensions. These challenges become more complex when viewed through the lens of recent IPM developments that emphasize digital integration, climate-smart approaches, and socio-ecological considerations.

Economic volatility and resource constraints significantly impact IPM implementation in pepper farming systems. Black pepper price fluctuations directly influence farmers’ pest management decisions, with low prices leading to reduced investment in crop maintenance and increased vulnerability to L. piperis infestations. Statistics from 2021 reveal that properly managed private black pepper plantations achieved yields of 845 kg/ha compared to 767 kg/ha in smallholder farms (DGEC 2021). This productivity gap of approximately 78 kg/ha represents substantial economic losses for smallholder farmers. The economic constraints particularly affect the adoption of modern IPM components such as monitoring tools, biological control agents, and improved cultural practices, which often require initial investments that smallholder farmers cannot afford during periods of price volatility.

Knowledge gaps and technological limitations present significant barriers to implementing modern IPM strategies. While contemporary IPM emphasizes digital agriculture integration and advanced monitoring systems (Dara 2019), Indonesian pepper farmers face considerable challenges in accessing and utilizing these technologies. The understanding of IPM among farmers often remains limited to basic pest control techniques rather than encompassing the holistic, ecosystem-based approach that modern IPM demands. This limitation is particularly evident in managing L. piperis, which requires comprehensive understanding of pest biology, ecology, systematic monitoring, and integration of multiple control tactics. The FFS approach, while valuable, has not fully incorporated these modern IPM concepts, and the lack of systematic evaluation of FFS effectiveness has hampered the development of locally adapted, practical IPM strategies.

Institutional and policy frameworks play a crucial role in IPM implementation success. As highlighted by Barrera (2020), effective IPM programs require strong institutional support and appropriate policy structures. However, government support for smallholder pepper farmers remains inadequate in many key producing provinces such as Lampung, Bangka Belitung, West Kalimantan, and East Kalimantan. Critical gaps include limited access to IPM-specific extension services, insufficient support for climate-smart agriculture initiatives, lack of infrastructure for implementing modern IPM monitoring systems, and inadequate mechanisms for knowledge sharing and technology transfer.

The socio-ecological context presents additional challenges in IPM adoption, as emphasized by Massimi et al (2022). There is limited recognition of farmers’ traditional knowledge in pest management and weak integration between scientific recommendations and local farming practices. The insufficient consideration of local ecological conditions in IPM strategies and poor coordination among farmers for area-wide management of L. piperis further complicate implementation efforts. These issues are compounded by limited access to market channels that value IPM-produced pepper.

Practical implementation of IPM faces several operational challenges that need to be addressed systematically. Samanta et al. (2024) emphasize that establishing consistent monitoring systems for L. piperis populations requires significant infrastructure and coordination. The limited availability of biological control agents and biopesticides, coupled with poor integration of climate data in pest management decision-making, creates additional barriers. Furthermore, the lack of coordination mechanisms for area-wide management approaches hinders the effective implementation of landscape-level IPM strategies.

These multifaceted challenges require an integrated approach that addresses both technical and socioeconomic aspects while considering the specific context of smallholder pepper farming in Indonesia. Success in implementing modern IPM strategies for L. piperis management will depend on developing balanced solutions that combine technological innovation with appropriate social and institutional support systems, while remaining sensitive to local conditions and farmer capabilities.

Conclusion

The management of L. piperis in Indonesian pepper farming systems requires a comprehensive transformation from fragmented pest control practices to an integrated, sustainable approach. Our critical review reveals that successful IPM implementation demands a coordinated action plan addressing technical, social, and economic barriers simultaneously. The foundation of this transformation relies on strengthening institutional frameworks through a coordinated network of research institutions, extension services, and farmer groups. Regional IPM demonstration sites will serve as practical learning centers, while standardized monitoring systems will enable data-driven decision-making. These institutions must support farmer education through field schools, hands-on training, and peer-to-peer learning networks, with materials adapted to local languages and contexts.

Economic sustainability forms a crucial pillar of successful IPM adoption. We propose establishing price premium programs for IPM-certified pepper, coupled with microfinance schemes to support implementation costs. Partnerships with exporters can create stable market channels, while cooperative buying programs can make biological control agents more accessible to smallholder farmers. Technical infrastructure development must parallel these efforts. Mobile technology-based pest monitoring networks, regional diagnostic centers, and early warning systems will provide the necessary tools for effective IPM implementation. Local production facilities for biological control agents will ensure sustainable access to key IPM components. Policy support is essential for long-term success. This includes streamlined regulations for biological control agent registration, development of IPM certification standards, and creation of incentive programs for adoption. Government funding mechanisms must be established to ensure program sustainability beyond initial implementation phases.

Implementation will follow a phased approach: establishing demonstration sites and farmer training in the short term (1 to 2 yr), developing infrastructure and implementing certification in the medium term (2 to 4 yr), and scaling successful programs with market linkages in the long term (4+ yr). Success metrics will track pest infestation levels, adoption rates, and economic outcomes, ensuring accountability and enabling adaptive management.

This systematic approach, supported by appropriate policies and institutional frameworks, will not only address current pest management challenges but also build capacity for responding to emerging threats in a changing agricultural landscape. Through these coordinated efforts, the Indonesian pepper industry can achieve sustainable and productive farming systems that benefit both farmers and the broader agricultural sector.

Acknowledgments

We would like to sincerely thank the anonymous peer reviewers for their insightful comments and constructive feedback, which greatly enhanced the quality and clarity of this review article. Their expertise and dedication to evaluating the manuscript are deeply appreciated. Their invaluable input has undoubtedly strengthened the credibility and rigor of our work. We are deeply grateful for their time and effort in reviewing our manuscript.

Author contributions

Elna Karmawati (Conceptualization [equal], Writing—original draft [equal], Writing—review & editing [equal]), Paramita Maris (Resources [equal], Writing—original draft [equal]), Rismayani Rismayani (Resources [equal]), Rohimatun Rohimatun (Resources [equal], Writing—original draft [equal], Writing—review & editing [equal]), Gusti Indriati (Resources [equal], Writing—original draft [equal]), Dwi Sunarto (Resources [equal], Writing—original draft [equal]), Sujak Sujak (Resources [equal]), Samsudin Samsudin (Resources [equal], Writing—original draft [equal]), Iwa Trisawa (Resources [equal]), Molide Rizal (Writing—original draft [equal]), Siswanto Siswanto (Conceptualization [equal], Formal analysis [equal], Resources [equal], Writing—original draft [equal]), Tri Lestari Mardiningsih (Resources [equal], Writing—review & editing [equal]), I Gusti Indrayani (Resources [equal]), Nurindah Nurindah (Conceptualization [equal], Formal analysis [lead], Writing—original draft [equal], Writing—review & editing [lead]), Agus Kardinan (Conceptualization [equal], Formal analysis [equal], Supervision [lead]), and Deciyanto Soetopo (Supervision [equal], Writing—review & editing [equal])

Funding

None declared.

Conflicts of interest. None declared

References