The SLR utilised a two-stage strategy to extract data following Jellason et al. (2024). The process of collecting data to be used in the SLR commences with defining the search string (Petersen et al. 2008), followed by a thorough examination of the publications (Alon, Apriliyanti & Henríquez Parodi 2021). We used titles, abstracts and keyword searches to select articles for inclusion in this review (Arshad et al. 2023). A comprehensive search of publications related to pest and disease management of African indigenous crops was conducted. This study used four broad databases: Web of Science, Scopus, CAB Abstracts and Google Scholar. The databases were selected because they provide the largest volume of high-impact scientific journals, primarily focusing on plant pests and disease management. The following keywords were used: (‘Indigenous crops’ OR ‘underutilised crops’ OR ‘neglected crops’ OR ‘traditional crops’ OR ‘neglected and underutilised crops’ OR ‘African vegetables’) AND (‘insect’ OR ‘pest’ OR ‘plant disease’ OR ‘Integrated pest management’ OR ‘disease control’). This process did not yield many studies; therefore, we manually searched for other peer-reviewed articles through Google Scholar and reference section of other articles.

The gathering of literature has characteristics that permit the attainment of the researchers’ purpose for the study (Akella et al. 2023). Clear and concise inclusion criteria set the boundaries of the review, allowing reliable, bias-free and reproducible results. The criteria for the selection of articles were based on several characteristics such as time frame, study topic, geographic scope, publication type, language and methodology (Table 1).

A total of 629 articles were retrieved from Scopus (173), Web of Science (25), CAB Abstracts (76) and Google Scholar (355) (Figure 1). After removing 210 duplicates, 419 articles remained. Title and abstract screening excluded 370 articles, leaving 49 for full-text review. Of these, 41 were excluded, resulting in eight eligible studies. An additional 21 articles were identified through reference list screening, bringing the final sample to 29 articles included in this SLR.

This study is a systematic literature review and did not involve the collection of primary data or any experiments with humans, animals, or plants. Therefore, ethical approval was not required. The research was conducted in accordance with institutional, national, and international standards for research integrity.

The findings indicate that the initial publication on pest and disease mechanisms for African UICs appeared in 2003 (Figure 2). Subsequently, there was a pause in publications from 2006 to 2010. Since 2010, the number of articles in this field of study has increased, with fluctuations. The highest number of articles (4) was recorded in 2023 and 2024. However, the research dedicated to UICs remains limited.

The most productive countries for pest and disease management of African UICs are Kenya and Tanzania, with six articles each, followed by Nigeria (n = 5) and Ethiopia (n = 4) (Figure 3). The Democratic Republic of Congo (DRC), Burkina Faso and Cameroon have two articles each, while the remaining countries (i.e. Uganda, Niger and Mali) have one article each. The variation in the number of articles published from each country can be attributed to the degree of research support in these countries for these crops.

The study also examined the most productive journals with respect to pest and disease management for UICs in Africa. Twenty-five journals that published articles in this field of study were identified, and the results revealed that the International Journal of Pest Management published the highest number of articles (n = 4), followed by Sustainability, with two articles each (Figure 4). The remaining journals had one article each.

The results of this SLR (Table 2) indicate that African indigenous cereal crops such as sorghum, millet and teff are affected by a wide range of insect pests, including grasshoppers, armyworms and the maize weevil (Ainsley & Kosoy 2015; Kitaba & Kuma 2022; Yêyinou Loko et al. 2017; Zhang et al. 2018). Among indigenous leguminous crops such as Bambara groundnut and cowpea, pests such as the cowpea aphid and the legume pod borer are significant, resulting in high yield losses (Godson-Ibeji, Aminu & Chikaire 2023; Muthama et al. 2024; Zhang et al. 2018). Another significant category for UICs is African indigenous vegetables (AIVs) (e.g. amaranth, eggplant, jute mallow, okra, nightshade and fluted pumpkin), which have been found to be affected by insect pests such as beetles, caterpillars and aphids (Anjorin, Jolaoso & Golu 2013; Bihon et al. 2023). These results were consistent with those reported by Ofuya, Okunlola and Mbata (2023). Apart from insect pests, the review found that indigenous African crops are threatened by fungal and viral infections. Blast diseases and parasitic weeds, such as striga, are key challenges affecting traditional cereal crops (Laizer, Chacha & Ndakidemi 2019).

Farmers cultivating UICs in Africa employ a combination of chemical and non-chemical methods to manage pests and diseases (Tonnang et al. 2022). Non-chemical approaches include cultural, mechanical and biological control methods, as well as the use of plant-derived insecticides obtained from locally available resources (Neuenschwander et al. 2023). The following sections provide a detailed discussion of these management strategies.

The utilisation of suitable cultural farming practices to curb or decrease insect pest infestations has been passed on from generation to generation in many African farming communities. Cultural farming practices are easily adopted because of their affordability.

Biopesticides are a naturally occurring subclass of pesticides derived from plants, animals and microorganisms, such as bacteria and cyanobacteria, and are employed to address the challenge of pests and pathogens (Kumar et al. 2021). Biopesticides, such as traditional chemical pesticides, have more benefits than their counterparts because they are eco-friendly and host-specific (Essiedu, Adepoju & Ivantsova 2020). In this SLR, only one study (Ochieng et al. 2022) reported that traditional vegetable farmers adopted biopesticides such as Metarhizium anisopliae, a fungus that acts as a biological control of different insect pests, and Trichoderma harzianum, which suppresses plant pathogens and promotes growth. Neem (Azadirachta indica) extracts have gained popularity in UICs for aphid control in cowpea farming because of their eco-friendly properties. Derived from leaves and seeds, neem biopesticides deter feeding and disrupt pest reproduction, offering a sustainable alternative to chemical pesticides (Muhammad & Kashere 2020). A study by Amadou et al. (2025) showed that neem seed extract reduced thrips density and Maruca vitrata larvae by 54.4% and 69.12%, respectively, increasing yield by 68.10% compared to controls. Other studies, such as Chang et al. (2003), found that adopting bio-based chemicals in farming ensures crop protection.

Mechanical pest control involves the use of physical approaches and barriers to manage pest populations, with the most prevalent strategies including manual weed removal, physical traps, pruning and tilling to aid in pest management. In this SLR, studies such as those by Omokaro (2024), Muthama et al. (2024), Ochieng et al. (2022) and Kibata and Kuma (2022) gave vital insights into several mechanical pest and disease control mechanisms adopted by African UIC farmers in countries such as Nigeria, Tanzania, Ethiopia and Kenya. Yêyinou Loko et al. (2017) examined farmers’ perceptions of termites in agricultural production. Their study identified several mechanical pest control methods, including the destruction of termite mounds. About 54.26% of the respondents actively destroyed termite mounds, especially those that impede ploughing. Although this practice targets eliminating termites that can destroy crops, it was ineffective because of the rapid rebuilding capabilities of the termites.

Regarding the sustainable farming of vegetables in Tanzania, Ochieng et al. (2022) noticed that farmers used insect traps to monitor and decrease insect pest populations in indigenous vegetables and pest scouts to enhance pest and disease control. Although mechanical pest control methods are vital, the study found that the adoption of this method is low (Ochieng et al. 2022). Omokaro (2024) focused on the farmers’ perceptions of the pest and disease control methods implemented in Nigeria. The findings revealed that approximately 37.5% of the respondents adopted mechanical methods as non-chemical plant protection strategies. Several strategies have been proposed for this purpose. For instance, manual weed removal was adopted by 43.75% in Edo State and 37.5% in Delta State, and mulching and tilling were used by 30% of the respondents in Edo State. Muthama et al. (2024) noticed that AIV farmers in Kenya used mechanical pest control methods such as physical traps, pruning of affected crop parts and insect nets.

The adoption of improved cultivars has emerged as an effective strategy in combating pests and diseases within modern agricultural systems (Abang et al. 2014; Mongi et al. 2016). However, their uptake among smallholder farmers in Africa, particularly in UIC, remains relatively low. This systematic review, although under few studies, provides evidence of the limited adoption of such practices by farmers and further indicates, in some cases, farmer’s willingness to adopt these improved varieties. For example, the research conducted by Owere et al. (2014) in Uganda found that the uptake of finger millet varieties with enhanced resistance to blast disease among small-scale farmers is limited. This is partly because of breeders not engaging farmers or addressing their concerns during the development of these cultivars. Notably, farmers showed a preference for new varieties that are resistant to blast disease, as they recognise the potential of these improved cultivars to safeguard their harvests from the disease (Owere et al. 2014). Mrema et al. (2017) found that in Tanzania, approximately 35% of farmers in the Igunga district, 15% in Kishapu and 10% in Meatu only were familiar with cultivating the improved new varieties, reflecting the low adoption rate of these enhanced cultivars.

Rural farmers can utilise these enhanced cultivars to combat pests and diseases, thereby boosting UIC yield advantages in their agricultural systems. These strategies aim to strengthen the crops’ inherent resistance to pests and diseases, which in turn decreases the dependence on chemical pesticides and encourages sustainable farming practices. Techniques for genetic enhancement, including host plant resistance, participatory plant breeding and molecular tools, have been crucial in creating pest-resistant crop varieties (Lefebvre, Boissot & Gallois 2020). Resistance genes sourced from wild relatives and innovative genes, such as those derived from Bacillus thuringiensis, have been successfully incorporated into crops to boost their resistance to significant pests and diseases (Dar et al. 2006). The implementation of genetically modified (GM) crops has proven successful in various regions (Ludidi 2022). However, its influence in sub-Saharan Africa has been minimal because of public opposition and the significant expenses involved in creating GM crops tailored to the diverse local agricultural systems (Kedisso et al. 2023). To explore the potential for adopting this GM technology in UIC crops, a focused research strategy that includes all relevant stakeholders might be crucial.