Survey on farmers’ awareness of mould infection in maize and groundnuts were conducted in various villages in Anseba, Debub and Maekel regions of Eritrea during the summer period between July and December 2023. We administered questionnaires to various farmers in the study areas to assess their knowledge and awareness of mold infections during storage. Maize and groundnut samples were collected for further analysis in the laboratory. It was observed that majority of the farmers had limited knowledge about the timing of infection, contamination, and risks associated with molds. However, more than half (57%) of the respondents were able to identify spoilt grains through rotting (48%), visible insects (21%), and discolouration (10%). The respondents reported several uses for infected grains: approximately 34% consumed them, 26% fed them to livestock and 18.4% sold them to unsuspecting customers. None of the interviewed farmers were aware of the term “mycotoxins” or the associated health hazards while 67% of the respondents did not know measures for controlling mould fungal infection. There was a positive correlation (p ≤ 0.001, r = 0.804) between farmers’ knowledge of mold fungi and their ability to understand mycotoxin contamination. Laboratory analysis revealed the presence of Aspergillus niger, A. flavus, A. parasiticus, Fusarium verticillioides and Penicillium spp. Grains from Koffo storage structure had the highest incidence of mold infection in comparison with other traditional storage structures. These findings indicate a general lack of knowledge about mold fungal infections and the risks among the respondents. Thus, the findings underscore the need for tailored interventions through the ministry of agriculture to promote good agricultural practices aimed at reducing mold and mycotoxin contaminations.

Awareness, Groundnuts, Knowledge, Maize, Mould Fungi, Mycotoxins, Traditional Storage

Maize (Zea mays L.) and groundnuts (Arachis hypogaea L.) are commonly cultivated by small scale farmers in Eritrea. Maize is an important crop mainly produced in the highlands areas of Maekel while groundnut which serves as a protein and fat supplement for this subsistent farmers is mainly produced in Anseba Region. Local meals including bread, fermented maize (bukil), boiling and roasted maize (Colo), as well as commercial products like lactic, citric, and alcohol acids, are all made from maize grains in Eritrea (Shimendi and Nitya 2016). The production areas for maize are characterized by droughts, heavy rains, relatively high average temperatures (>30 °C), high relative humidity, and sporadic floods which have an influence on mold contamination in the field and storage (Shimendi and Nitya 2016). The second major lowland oilseed crop is groundnut, which is high in protein, lipids, minerals, vitamins, and antioxidants as well as health-promoting bioactive substances like arginine, tocopherol, and resveratrol (Varlath and Janilla 2017; Abady et al. 2019). The crop is cultivated in the country’s warm lowlands, which are characterized by severe moisture stress, particularly during flowering. Both the above-ground and underground portions of the plant are impacted by diseases, inadequate production and post-harvest methods, and a lack of improved varieties.

Maize and groundnuts are highly susceptible to toxigenic mold fungal infection specifically from the genera Aspergillus, Penicillium, and Fusarium, and subsequent mycotoxin contamination. Aspergillus and Fusarium species invade maize at different production stages at pre- and post-harvest handling (Chulze 2010).

Losses in maize and groundnuts can be as a result of fungal contamination forming molds that results in discoloration and fuzzy appearance of grains. Mold contamination in food grains is widespread in stored grains, is a food safety concern for the many consumers and is associated with the production of toxic metabolites (Suleiman 2015; Kyei et al. 2021). The infection by these mold fungi on maize and groundnuts result in colour change, decrease in nutritional values, and overall quality of the grains through contaminations with mycotoxins (Kyei et al. 2021). Mycotoxigenic fungi are common in the tropical environments, and maize and groundnuts are excellent substrate for the mycotoxin producing fungal species (Mutiga et al. 2014). A significant issue in Sub-Saharan Africa, where agronomic, storage, and climatic conditions encourage the growth of fungi and the production of toxins, are mycotoxins, which are secondary metabolites of molds that are poisonous to both humans and animals (Kumar et al. 2008; Degraeve et al. 2016; Suleiman 2017). The most important groups of mycotoxins are aflatoxin and fumonisin which are carcinogenic, can cause impairment of nutrient absorption, fetal and infant growth retardation, immuno suppression, and liver cancer, (Phokane et al. 2019). Both maize and groundnut can be contaminated with mycotoxins producing fungi in the field and in storage (Mupunga et al. 2014; Beukes et al. 2016; Njoroge et al. 2017). Surveillance of mycotoxin is a problem and difficult to implement in the Africa. For instance, in Kenya, small scale farmers produce nearly 75% of the total maize either used for home consumption or for trading purposes (Mutiga et al. 2014). However, countries can only manage these mycotoxins through policy regulations and regular monitoring for acceptable limits which are not available in the country.

According to Hell and Mutegi (2011) pre and postharvest practices in maize influence mycotoxin accumulation. Pre-harvest contamination is associated with damage by birds, insects, stressful growth conditions and crop susceptibility. While postharvest contamination is a result of inoculum amount, and successful colonization of the hosts at pre-harvest stage. In Eritrea farmers store maize in different structures such as Koffo, mashumae and guffet which expose maize to damages by insects and fungal pathogens. As a result, farmers lose money when fungal and insect pests contaminate grain crops before and after harvest. In spite, of the reported presence of these mycotoxigenic fungi, there is lack of knowledge and awareness on mould fungal infection and mycotoxins among farmers which constitute a serious threat to consumers. For instance, in Uganda, losses up to US$ 577 million occur every year (Lukwago et al. 2019). Very little research has been done on this topic and to our knowledge, this will be the first report on the occurrence of the mold fungi on cereal grains. Creating awareness among the farmers on maize production practices and their influence on contamination is crucial in mitigating the risks of mycotoxin contamination within the communities surveyed. Also identification of these microorganisms will help in strategizing mitigation measure related to mycotoxin problems. Therefore, this study was undertaken to evaluate awareness of the presence of mould fungi on maize and groundnut grains among small scale farmers.

In many third world income countries with high prevalence of mycotoxin, knowledge and awareness among the rural farmers is still low. Thus, the present study was intended to assess farmers’ knowledge and awareness of mould infection in maize and groundnuts. As far as we are aware, this is the first study on mold associated with mycotoxins in the country. The results indicate total lack of knowledge among the respondents, an outcome that closely mirrors those reported by Magembe et al. (2016) where majority of the farmers did not have knowledge on mould infection and did not understand risks associated with consuming the contaminated grains in Tanzania. The findings are also comparable to those reported by Kimanya et al. (2014), Mboya et al. (2012), TFDA (2012), Shirima et al. (2014), Kamala et al. (2016) where there was lack of awareness on mould growth and mycotoxins production. However, the results contradict those reported by Kyei et al., (2021) where majority of the respondents were aware of molds and mycotoxins in Bangladesh. According to the authors poor harvesting practices and postharvest handling of grains were the major factors associated with mould infection, an observation that was mentioned by the majority of the farmers in this study. The lack of experience in mold fungal contamination during field and post-harvest stages of crop production among the surveyed respondents indicates a limited exposure or lack of knowledge of post-harvest pathogens affecting cereals especially Aspergillus, Penicillium and Fusarium species. Suleiman et al. (2017) found that a significant percentage of respondents knew very little or nothing about mycotoxin contamination. Gong et al. (2002) suggest that raising awareness and knowledge about mycotoxins could help lower the amount of mycotoxin contamination in cereal grains. Furthermore, a lack of public knowledge about mycotoxin contamination exacerbates the issue of mycotoxin contamination in agricultural commodities in Sub-Saharan Africa.

In the present study the respondents’ grain handling activities was relatively poor. For instance, when the farmers were asked whether they sort out the grains, cleaned the store, majority indicated they never did and as such this acted the source of inoculum to the newly introduced grains. The results are similar to those reported by Magembe et al. (2016) in Tanzania where farmers did not sort out their harvests to remove bad quality grains. According to Suleiman et al. (2017) poor postharvest practices can lead to rapid deterioration of grain quality, dry matter losses and mold growth. The respondents also indicated they know bad quality grains through discolouration, insects damage, moldiness, however, they still consumed, sold to other farmers and even fed them to livestock. The same results were reported in Malawi where the respondents knew about risks associated with mycotoxins, however, they still consumed the contaminated grains due to shortage of food (Matumba et al. 2015). The same outcome was reported in Zambia where high insect and fungal infestation was reported in Maize grain samples collected from Chongwe, Solwezi and Mwinilunga (Kankolongo et al. 2008).

Farmers knowledge of mold fungi positively correlated (p ≤ 0.001, r = 0.804) with their ability to understand mycotoxins contamination. Moreover, findings also revealed a positive association (p ≤ 0.001, r = 0.247) between farmers’ knowledge on mold infection and cleaning of stores. Furthermore, results also revealed that the level of education had a negative correlation (p ≤ 0.001, r = -0.291) with how often the respondents cleaned their stores. There was positive correlation (p ≤ 0.001, r = 0.309) between the knowledge on mould infections and age of the respondents. Dosman et al. (2001) indicated that individuals with higher education levels are more likely knowledgeable and aware of mycotoxins, however, in our study there was a negative correlation between mold infection and education level. This is likely because majority of the respondent were either primary school drop outs or had no basic education levels. Majority of the farmers lack resources and may not access literature related to fungal or mycotoxin contamination. High farmer to extension officers’ ratio and poor access to publications due to lack of internet facilities is also a contributing factor. It is vital to minimize mycotoxin contamination and knowledge of good agricultural practices be transferred to farmers as well as extension officers (Phokane et al. 2019) According to Adekoya et al. (2017) individuals with low education levels rely on transmittable skills since mycotoxin topic is not covered in primary and secondary school levels. Studies have posited the importance of educational attainment in public awareness of food safety (Oni and Inedia. 2005).

Aspergillus species such as Aspergillus niger, A. flavus, A. parasiticus, and Penicillium spp. were isolated from both maize and groundnuts samples. Fusarium verticillioides was isolated exclusively from the maize grain samples. Aspergillus spp. exhibited rapid growth with colonies producing white, yellow, yellow-brown, brown to black or shades of green colouration and under the microscope, they had dense erect conidiophores. Penicillium spp. produced blue coloured spores while Fusarium verticillioides produced pinkish colonies on PDA and produced chains of conidia under the microscope. The fungi identified in this study are similar to those reported by Bandh et al. (2010); Keta et al. (2019); Aminu and Keta (2021). In a study conducted in Zambia, Kankolongo et al. (2008) recovered various fungi from samples with the most prevalent one being Aspergillus flavus, A. niger, Aspergillus spp., Fusarium verticillioides, F. solani, Fusarium spp., and Penicillium spp. The results also are similar to those reported by Nyirahakizimana et al. (2013) in Kenya where various Aspergillus species were isolated from groundnuts collected from formal and informal markets. The authors attributed the high incidence to handling practices such as sorting, and storage conditions. The same outcome was reported in Ethiopia where different Aspergillus species such as Aspergillus niger, Aspergillus flavus, Aspergillus ochraceus, Aspergillus parasiticus and Penicillium species were found infecting groundnuts (Mohammed and Chala 2014). The problem of these mycotoxigenic fungi go as wide as European countries, for instance, several studies have also confirmed the presence of Aflatoxin producing fungi in Europe (Pleadin et al. 2014; Camardo et al. 2015; Baranyi et al. 2015). These fungi inhabit variety of environments and require different conditions for optimal growth and reproduction. The environmental conditions significantly influence toxin producing fungi and may invade food at the pre-harvesting, harvest-time, post-harvest handling, and storage (Birgen et al. 2020). Aspergillus and Penicillium spp. are ubiquitous in nature, and are therefore common source of contamination to grains. Our study found high frequency isolation of Aspergillus spp, an outcome supported by findings of Ofgea and Gure (2015) and Kankolongo et al. (2008) where Aspergillus was the most abundant and dominant genus. In Kenya, the frequently isolated storage fungi in maize grains are the Aspergillus, Penicillium, Fusarium and Alternaria (Birgen et al. 2020). The high prevalence of this Aspergillus species may be attributed to the moisture content of maize and other environmental factors that favour the spread and colonization of this fungal genera. This study confirms the high occurrence of these mould fungi in grains stored by farmers. The continuous exposure to mycotoxins from contaminated grains has been reported in Kenya (Lewis 2005), South Africa (Sydenham et al. 1990), West Africa (Turner et al. 2005) and other developing countries (Bhat and Vasanthi 2020) with implications to health of consumers and the economy of the country.

The storage method significantly influenced the population of fungal pathogens attacking maize and groundnuts grains. Cereal grains stored in Koffo had the highest occurrence of mycotoxigenic fungi when compared with the other storage types. The results herein are similar to those reported by Lamboni et al. (2009) in Togo where Aspergillus, Penicillium and Fusarium oxysporum were observed on traditional storage facilities infecting maize. Similarly, reports by Julian et al. (1995) in Honduras reported occurrence of Aspergillus, Penicillium and Fusarium moniliforme as the predominant storage fungal pathogens affecting maize. This high incidence in the current study could be because farmers mixed old grains with new ones, and often leave koffos open for an extended period of time. Some of these structures provide openings through which pests gain entry to the store thereby damaging the maize. Insect damage associated with Sitophilus zeamais, Prostephanus truncatus, Tribolium castaneum, and Sitotroga cerealella are was observed as the most common attribute associated with bad quality maize. Others observed were moldy rotten maize and shriveled maize grains. Insect pests are the principal cause of post-harvest losses that predispose cereal grains to mycotoxigenic fungi (Hell et al. 2000; Danso et al. 2018). The insects break the grains, and their metabolic activities results in increased relative humidity thus rendering them vulnerable to invasion by fungi (Hell et al. 2000). The type of damage and storage pests observed in this study are similar to those reported by Adugna and Ahmad (2006) who documented the use of plastic bags, barrel, sacks, and Koffo which are predominantly used as the storage types by farmers in Eritrea. In a survey done by Adugna and Ahmad (2006) it was reported that most of the stores were found to contain storage pests causing serious damage to grains. According to Birgen et al. (2020) grains are African traditional storage structures exposes the grains to infection by fungi leading to contamination by mycotoxins. These storage facilities are predisposed to elements like water leaks that results in increased moisture contents creating condition for growth of fungi.

The findings demonstrate a huge knowledge gap regarding mould fungal infection among farmers in the study areas. Majority of the farmers could not identify infected grains and a few of the farmers fed these grains to livestock, consumed them and even sold them at the local markets. The use and consumption of these contaminated grains constitute health risk among the consumers in the study areas. The lack of awareness identified in the study should form the basis for developing a tailored intervention strategy to prevent mold and mycotoxin contamination. Knowledge transfer should be initiated through awareness campaigns to inform farmers of the threats and effects of mycotoxins on humans and animals and their implications to trade. Additional, surveillance should be done to monitor mycotoxin contamination. To attain this, there should be access to information and increase in the number of extension officers who will train farmers on these fungal contaminants, mycotoxins and management practices.

We are grateful to the farmers from the three regions for the information provided. We are also grateful to the students who participated in gathering of the information. We also thank Prof, Adugna Haile, Head of Department of Plant Health at Hamelmalo Agricultural College, Eritrea for the support accorded during the period of the study.