**1. Introduction**

Maize cultivation occupies almost 70% of the total area devoted to cereals in Benin. The area sown for maize production was 1,003,715 ha in 2016 across the country, representing the production of 1,300,000 tons of maize MAEP [1]. Crop covers 53 municipalities out of the 77 municipalities in Benin and is present in the seven Agricultural Development Hubs (ADHs). In Benin, maize is the staple food and the only cereal that generates exportable surpluses to neighboring countries, namely, Niger and Nigeria Sohinto et Aïna [2].

Efforts have been made over the past 10 years to increase the production of maize by improving productivity and subsidizing seeds through several projects, including the West Africa Agricultural Productivity Program (WAAPP), as well as technical and financial partner projects. Efforts to increase the production of maize have also included the provision of fertilizers and herbicides. Adégbola [3] analyzed the impact of the adoption of improved varieties of maize and concluded that this practice increased the yield by 9.77 kg/ha. Thus, the adoption of improved varieties of maize improved the income from production by 2427 FCFA per hectare. In the distribution of maize production costs, labor is the highest variable cost item in all maize production systems in Benin. The supply of foodstuffs, such as maize, to the population, presents a temporal and spatial gap between production and consumption. This gap is filled by the storage of maize.

**Citation:** Sissinto Gbenou, E.; Adégbola, Y.P.; Hessavi, M.P.; Zossou, S.R.C.; Biaou, G. On-Farm Assessment of Maize Storage and Conservation Technologies in the Central and Northern Republic of Benin. *Agriculture* **2021**, *11*, 32. https://doi.org/10.3390/ agriculture11010032

Received: 6 November 2020 Accepted: 16 December 2020 Published: 5 January 2021

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During this storage stage, maize stocks suffer losses that reduce the potential quantity of the food and lead to a reduction in agricultural income. To mitigate the magnitude of the losses and to allow producers to have a relatively large marketable surplus, improved maize storage and conservation technologies were introduced from 1996 to 2004 Fandohan, Maboudou [4,5]. Despite advances in research in the implementation of innovations that can significantly reduce these loss rates, it has been found that the adoption of these new techniques has not been effective among many producers who prefer to continue their endogenous practices Maboudou [6]. Storage losses lead to losses of seeds, fertilizers, pesticides and labor during the production of stored maize, and significant postharvest losses will reduce farm income.

Adégbola [7] showed that the use of improved storage technologies provided a significantly higher income than previous or endogenous local technologies. These technologies allowed adoptive producers to acquire more material than nonadopters. Additionally, the adoption of these improved technologies contributed to the improvement of production factors (land, capital, labor). Previous research has shown that the adoption of improved maize storage technologies had a positive impact on income and hence on the acquisition of material goods and investments in human capital and production. Based on the analysis of Hinnou and Aloukoutou [8], it appeared that the financial means, the difficulty of construction, the risks of intoxication (due to the smell of sofagrain after several months of storage), the positive impact of accessibility to building materials of granaries and the positive impact of the mastery of construction techniques were the main issues affecting the adoption of these improved technologies. Hinnou and Aloukoutou [8] concluded that in the North, it was necessary to promote storage in bags with non-winnowing after ginning and the use of the repellent leaves in clay granaries. In contrast, in the South, improved granaries made of plant materials with repellent leaves, especially neem, and bags of grain maize with "Phostoxin" were the best possible alternatives. Jones et al. [9] evaluated the storage of maize grains with the use of sofagrain and in Purdue Improved Cowpea Storage (PICS) bags without chemical conservation measures and determined that the weight losses were only 0.5% without the use of chemicals in PICS bags. They concluded that the PICS bag had a good chance of adoption in Ghana, Tanzania, Kenya, Malawi and Mozambique, where tests have been carried out.

Over the past ten years, with the LISA projects of the NGO Louvain Coopération and the Postharvest Project of HELVETAS Swiss Intercooperation, storage technologies have been developed and introduced in rural areas in central and northern Benin. The following storage technologies have been tested in Benin and compared to the existing technology used by producers: the polypropylene storage bag ZeroFly®, the metal silo and the PICS bag. The polypropylene bag is one of the most used materials by producers in Benin for storing maize. This technology can be classified as "peasant know-how". The situation is the same for earthen granaries, which have been improved over time. Maize stored in polypropylene bags with or without treatment undergoes postharvest losses ranging between 3.66% and 13.21% Sissinto-Gbénou [10]. Recently, several studies have highlighted the effectiveness of hermetic storage technologies for reducing losses of maize stored in Benin and in its subregions [11–15]. In addition, the socioeconomic aspects of storage technologies were partially addressed by Adégbola [7] and Adéoti et al. [16]. Therefore, the objective of this research was to evaluate the storage losses and profitability of improved maize storage technologies in central and northern Benin. Financial profitability is an important criterion for producers as economic agents and will allow them to decide whether to adopt these technologies. The method of Pantenius [17] was used for loss rates, and the economic method of Gittinger [18] was used to assess the profitability of different maize storage and conservation technologies.
