This study was conducted in Northern Uganda in the districts of Adjumani, Amuru, Apac, and Dokolo during October and November 2020 (Figure 1).

Northern Uganda was chosen since the promotion and dissemination of HSTs were previously carried out in the region by several projects since 2012. Villages for the survey were selected with the help of district and Sub-County agricultural extension officers in the study area. The geographical coverage was limited to the selected districts due to financial and logistical constraints.

Three hundred and six (306) smallholder farmers were purposively selected and interviewed from 43 villages across the four districts of Northern Uganda. In each village, seven (7) respondents (each representing a household) who are active farmers were randomly selected to participate in the survey. The selection of villages was based on active engagement in agricultural production. A pre-tested semi-structured questionnaire with open and closed-ended questions was designed and used to elicit information from respondents.

Data were collected on household demographic and socioeconomic characteristics, access to agricultural information, crop production details, grain storage practices, hermetic storage awareness, use and constraints to adoption, and grain prices at harvest and during the lean seasons. Key informant interviews were used to validate some of the information obtained from the survey. Quantitative and qualitative data collected were coded, entered, and analyzed using the Statistical Packages for the Social Sciences (IBM SPSS Statistics 20; New York, United States). Descriptive statistics and frequencies were used to present the findings of the study.

The use of probability models to identify the key factors affecting the decision to adopt a new technology is commonly used [26]. Logit, Probit, and Tobit models are commonly used statistical models. To understand the adoption of hermetic storage in the study area, the binary logit model was used as is commonly used in new technology adoption studies. The binary logit model was used to determine the effect of socioeconomic variables influencing the adoption of HSTs. In this kind of model, the dependent variable “hermetic storage adoption” is a dichotomous variable and takes the value of 1 if the respondent adopts the use of hermetic storage and 0 otherwise. Socioeconomic variables such as age, gender, marital status, education, membership of an association, etc. were used in the logit model. The variables used in the regression analysis to develop adoption models are shown in Table 1. These variables were selected based on adoption literature and the experience of grain storage adoption factors [26] [39].

Multiple logit regressions were developed in which the dependent variable (hermetic storage adoption) was expressed as (Rabé et al., 2021):

Y = β 0 + β 1 A + β 2 B + β 3 C + β 4 D + ⋯ + β i N + e i (1)

where

Y is the adoption of hermetic storage;

β 0 is the constant term in the logit model;

β i are the coefficients of the adoption factors to be estimated;

A , B , C , ⋯ , N are the independent variables whose effects on the adoption of hermetic storage were investigated; and

e i is the model error term.

Northern Uganda is a kind of shrubby Grassland Savannah vegetation that receives a bimodal rainfall pattern from March to May and August to November annually. Rainfall patterns have, however, been unpredictable in the past few decades. The demographic and socioeconomic characteristics of the respondents are shown in Table 2. Among the respondents, 55.9% were male while 81.0% were married. Forty-nine percent of the respondents were aged 18 - 35 years, and 59.5% had only completed primary school education. A large number of the respondents (41.8%) were smallholder farmers who owned 3 - 6 acres of land. Seventy percent of the respondents had more than 50% of total cultivated land under grain production. About 32% of the respondents earned between UGX 500,000 - 1,000,000 (USD 136 - 272) as their annual household income. About 37.6% of respondents cultivate family-owned land while 29.4% use both family land and rented land (Table 2).

At least 12-grain crops are cultivated by smallholder farmers in the survey area (Data not shown). These crops include legumes (common beans, pigeon peas, mung beans, groundnuts, and cowpeas), cereals (maize, finger millet, rice, and sorghum), and oil crops (soybean, sesame, and sunflower). Maize, common

n is the number of respondents. *1USD = 3674UGX at the time of the survey study.

beans, soybeans, and groundnuts are the dominant crop commodities cultivated by 85.3%, 42.5%, 32.0%, and 28.4% of the respondents respectively. The least cultivated crops were cowpea, green gram, and pigeon pea cultivated by 1.0%, 5.2%, and 5.6% of the respondents respectively.

Figure 2 shows the main source of livelihood of the respondents in the surveyed region. Overall, crop production is the main source of livelihood practiced by 99.7% of the respondents, followed by livestock rearing (86.9%) and self-employment (23.5%). Crops are grown primarily for food security and household financial requirements such as school fees for the children. Besides crop production, farmers kept chicken, cows, goats, sheep, and pigs for income, diversification of their diets, and to fulfill other socio-cultural purposes. Other sources of livelihood for the farmers included casual labor, brick or charcoal burning, and formal employment.

Maize was the commodity harvested in the largest quantity while green gram was the least harvested among the traditional grain crops in the study area (Figure 3). The most stored commodities following harvest were pigeon pea (95.3%), sorghum (80.6%), green gram (80.3%), common beans (75.7%), and finger millet (74.2%). The least stored commodities were sunflower (5.0%) and soybean (39.6%). Three months after harvest, most grain stocks in smallholder farming households were reduced to between 18.8% to 52.9% of the harvested quantity except for pigeon pea which still had an average of 59.3% remaining

after three months. Sunflower remaining after three months was less than 1% of the initial harvest.

Figure 4 shows the variations in the market prices of grain commodities between the peak (harvest) seasons and lean periods in Northern Uganda. Variations in grain prices were significant (p < 0.05) for all grain commodities but were insignificant (p > 0.05) for rice, pigeon pea, and cowpea. The differences in

prices between the lean season and harvest season amounted to USD 322, 302, 271, and 262 per metric ton for pigeon pea, common beans, sesame, and green gram.

Table 3 shows how grain farmers in Northern Uganda access general agricultural extension services, information, and training specifically on HSTs. About 66.3% of the respondents mentioned having had contact with agricultural extension services provided in their area of operation. Of those who received extension services, 50.7% had access to extension services from Non-Governmental Organizations (NGOs) while 40.4% accessed government extension or research services (Table 3). Concerning HSTs, a large number of respondents received information on HSTs from NGOs (50.0%), radio (20.8%), and farmer group extension agents (15.7%) (Table 3). A paltry 4.7% of the respondents received information on HSTs from government extension agents. This deviation emphasizes the little effort put by the government to promote and disseminate improved grain storage technologies to Ugandan smallholder farmers in Northern Uganda. Other farmers were also important for the dissemination of improved grain storage technologies as 5.9% of the respondents obtained HST information from fellow farmers. About 75.5% of the total respondents had received training on HSTs. Training on HSTs was provided mainly by extension officers/village demonstrations (77.8%) and other farmers/neighbors (8.9%).

Awareness of new agricultural technology is a key to promoting farmer acceptance and adoption. Fifty-three percent of the respondents were aware of some

form of grain HSTs whereas 46.7% were unaware and had no prior knowledge of any form of HSTs (Table 4). The SuperGrain bag (35.3%) was the most commonly known form of hermetic storage in Northern Uganda followed by the PICS bag (34.9%), metallic silo (15.5%), and plastic silo (14.4%) (Figure 5). The respondents were unaware of any other hermetic storage brands marketed in Uganda outside those indicated. Of those aware of HSTs (163), only 33.1% had ever used or were currently using one or more of the HSTs. Of these, 34.5%, 51.7%, 1.7%, and 12.1% had ever used or were using PICS bag, SuperGrain bag, metallic silo, and plastic silo respectively. 96.3% of the HST users do not apply chemical insecticides to grains before and during storage.

Farmers use HSTs to store grains for several reasons. Insect pest control (83.1%), mold management (4.6%), rodent management (7.7%), and others (4.6%) were the main reasons cited by respondents for choosing HSTs over traditional storage methods (Table 4). For those who were aware of HSTs but are not using them, the main reasons for not using HSTs for grain storage were

n is the number of respondents.

lack of availability (50.2%), high cost (37.8%), and lack of knowledge on how to use (6.9%) among others (Table 4). About 55.6% of HST users had received their HSTs for free while the rest acquired them through purchasing.

Among the HST users, 51.9% of the respondents said they would like to reuse their HSTs for at least three seasons. About 44.4% of the respondents opened their hermetic storage containers every month while 25.9% opened after every three months (Table 4). Most of the respondents (64.8%) gave the reason for HSTs opening as to obtain grains for sale and consumption. To improve HSTs availability and use, most farmers think the use of farmer-based organizations (41.4%) and retail shops in their villages (34.0%) would be the most suitable approaches.

When asked about the benefits of using HSTs, the respondents described several benefits that originate from the adoption of improved grain storage technologies. Among the HST users in our study, the benefits of using hermetic storage over conventional storage technologies included improved food availability in the farming households, household income, improved grain quality, and nutrition reported by 98.1%, 90.7%, 100%, and 90.7% of the respondents respectively (Data not shown).

The binary logit regression analysis was used to identify the important factors affecting the decision to adopt the use of hermetic storage in Northern Uganda. The determinants of adoption of HSTs are shown in the Logit model estimation results shown in Table 5. The logit model incorporates both quantitative and

qualitative variables to determine the significance of the adoption factors. Of all the independent variables, only one variable significantly affected the adoption of hermetic storage by users. This variable was training in the use of hermetic storage (p = 0.002). Respondents who received training on HSTs were significantly more likely to adopt the use of hermetic storage technology.

In Uganda, agriculture is the mainstay of the population upon which people directly or indirectly derive their livelihoods. Subsistence agriculture in the country contributes significantly to the food and income requirements of about 85% - 90% of households in Uganda [40]. In our study, young people between 18 - 35 years made up nearly half (48.7%) of the surveyed population. The population of Uganda is one of the youngest in the world [41]. Young farmers are considered more energetic and productive in agricultural work as most fieldwork activities in smallholder farmer settings of SSA require physical effort characteristic of young people. Besides, young people are more likely to adopt new agricultural technologies faster than their aged counterparts [42]. The majority of Ugandan farmers are smallholder farmers who produce food chiefly to meet their food and income requirements. At least 76% of the surveyed population owned between 1 - 6 acres of agricultural land, with grain production accounting for much of the total land under cultivation. Grain production is a key social and economic activity in Uganda, contributing to food security and smallholder farmers’ household income requirements [43] [44]. This indicates that priority is given to grain crops when it comes to land allocation compared to traditional root and tuber crops in the study area. The majority of the respondents are low resource farmers (63.7%), earning up to a maximum of UGX 1,000,000 (USD 286) as their annual household income. Such low resource farmers may find it difficult to invest their little resources in improved grain storage technologies.

Northern Uganda receives two rainy seasons from March to May and August to November each year, and there are at least six to eight months of grain storage before the next harvest season. This duration of food storage may affect the food security and household income of smallholder farmers especially if they lack better storage technologies. While food production is a seasonal activity, food consumption is an ongoing activity that must be met regularly and adequately [45]. Farmers should thus be able to store enough food to meet their household food and income needs during the lean periods. From our study, most smallholder farmers remained with only a limited quantity of grains in their food stores just three months following harvest. This indicates the vulnerability of many smallholder farmers during the lean periods and the struggle they go through to meet their household food needs between one harvest season and the other. In a study carried out in Tanzania, crop stocks were less by 63% - 94% of the harvest amount after just one month of storage [8].

Shortly after harvest, many smallholder farmers opt to sell most of their crops for several reasons. These include raising money for school fees, household requirements, and the perception of grain surplus above storability [8]. Besides, the onset of the crop harvest season coincides with financial pressures that farming households have been subject to during the lean periods, with the immediate option being the sale of some or all of the crop harvests. Other farmers also sell their surplus crop harvests for fear of losing them to the agents of deterioration during storage [22] [46]. When sold immediately after harvest, households will be forced, in a few months, to buy grains at relatively higher prices than sold to meet their food needs [12] [47] [48]. Among other factors, this has kept many smallholder farmers of SSA in perpetual poverty.

For all the grain commodities produced by farmers, prices during the lean seasons were significantly higher than during the harvest seasons, amounting to gains of US $322, 302, 271, and 262 per metric ton of pigeon pea, common beans, sesame, and green gram sold in the lean periods. This benefit of fetching higher prices when grains are sold during the lean periods is an opportunity for smallholder farmers to invest in and use effective and sustainable storage solutions such as hermetic storage that retain higher crop quality for longer in storage. The ability to be able to store crops from harvest time until when local market prices are favorable could improve smallholder farmers’ incomes that would eventually break the perpetual cycle of poverty resulting from farmers’ poor grain storage habits [8]. Besides fetching higher market prices, storing grains in superior storage technologies that avoid storage losses can guarantee farmers’ food security in farming households [48].

Agricultural extension services are important to enhance farmer knowledge and awareness of the availability of new and improved farming technologies [49]. A large proportion of the respondents in the study area had access to general agricultural extension services. Northern Uganda has several extension service providers including NGOs, governmental agencies, and other private entities. Those with access to extension services in the study area relied on NGOs, Government research and extension services, and farmer-group extension service providers. NGOs accounted for the largest source of extension services followed by Government research and extension services. The overreliance of smallholder farmers on NGOs to offer extension services is worrying since the withdrawal of the services of such an entity at any time would drastically affect smallholder farmers. The lack of access to agricultural extension services by about 33.7% of the population could be attributed to limited government support to provide extension services to these farmers. About 8.0% of the respondents received extension services from farmer group extension workers. Sebaggala and Matovu [50] argued that formal extension workers are not the only source of agricultural extension information for farmers as other informal sources have emerged. It has become common to see established farmer groups in Uganda employ skilled and trained personnel to provide agricultural extension services to their farmer group members in agricultural communities.

The vast majority of respondents who were aware of hermetic storage had received some form of training on its use, primarily from agricultural extension workers in their area. The efforts of development partners mainly the WFP to promote sustainable post-harvest solutions that reduce grain handling and storage losses brought to the knowledge and use of HSTs in Northern Uganda. Despite these and other stakeholders’ efforts, our study indicated that awareness and use of HSTs remain low in Northern Uganda. Hermetic storage bags, plastic silos, and metallic silos were among the first HSTs promoted in Uganda between 2012 to 2016 by WFP and other partners [7] [38]. Since then, several other organizations including the private sector have picked interest in activities such as technology dissemination, research, and manufacturing to meet the needs of smallholder farmers to improve grain storage in the region.

Our study indicated that awareness and use of HSTs in Northern Uganda are low among the surveyed farmers, and the same could be true for the whole country. Despite the promotion and dissemination of HSTs in Uganda by development partners including WFP from 2012 to 2016 and the inclusion of promotion and dissemination of HSTs into the activities of many development partners, a large proportion of the population in the surveyed area are still unaware of improved forms of grain storage. Among those who are aware, the use of HSTs to store grains was even much lower as only 18% of total respondents were using one or more forms of hermetic storage. Compared to the study of Moussa, Lowenberg-DeBoer [51] where there was a 70% adoption level of HSTs in Burkina Faso and Niger for the storage of cowpeas, there is still a low adoption rate of hermetic storage in Uganda. The main reason for farmers to use HSTs was the management of insect pests during storage. Insect pests are the greatest challenge to stored grains, causing significant quantity and quality loss of up to 40% in some commodities [52]. By using HSTs, insect pests cannot thrive due to the creation of interstitial modified atmospheres of low oxygen and high carbon dioxide [48] [53] [54]. Due to inadequate oxygen supply, cessation of insect feeding, growth, development, reproduction, and eventual death occurs for insect pest species and their life stages [55]. Besides, the lack of oxygen blocks the supply of vital metabolic water leading to the desiccation of insect pests and their life stages [55].

The main constraints to hermetic storage technology adoption in Northern Uganda were lack of availability and high cost compared to conventional grain storage methods. In West and Central Africa, lack of availability of HSTs and lack of information were noted as the top most important constraints hindering farmers from using hermetic grain storage [26]. In a related adoption study in West Africa, lack of availability and high price were the top reasons for the low adoption of PICS bags for grain storage [26]. The users of hermetic storage have to strike a balance between technology cost, availability, and durability [32]. The initial acquisition cost of HSTs is a major constraint to smallholder farmers in Uganda. Metallic silos cost about USD 35 for a 100 kg silo and USD 2 - 4 for a 100 kg hermetic bag compared to the popularly used woven PP bag which cost at most USD 0.4 for a 100 kg bag. From this, it is clear that the cost of HSTs is highly substantial for smallholder farmers given the limited financial capacity of smallholder farmers of SSA [12].

Among the HST users, most farmers received them for free or paid a small fraction of the total costs as promotion incentives offered by the promoters of the technology. To ensure rapid awareness and adoption of HSTs, development partners and other promoters of new storage technologies initially offer them to participating households at a small fraction of the total technology fee or completely free [22]. This is usually done so that the beneficiary farmers and other farmers would learn about the benefits of the technology and later take personal interest to buy them for improved food security and incomes in their households. Most of the surveyed farmers opened their HSTs periodically after sealing to obtain grains either to be used as food or to sell for income to meet their household needs. While the opening of hermetic storage interrupts the hermeticity principle, sealing the container shortly after has been shown not to significantly impact grain quality [56].

The logit regression model results showed that training on HSTs was the main predictor of the adoption of storage technology in Northern Uganda. While other factors such as age, education, gender, and marital status among others are known to affect the adoption of storage technology [26] [39] [57], these were not the main factors in our study. It has been demonstrated that awareness-building exercises increase the adoption and use of new improved storage technologies [58]. Training and dissemination of knowledge and information about new technologies thus play a key role in raising awareness and subsequent diffusion of technologies among targeted users. Unlike in other hermetic storage adoption studies, education, membership in a farmer association, household headship, access to radio, and access to extension services did not significantly affect the adoption of hermetic storage in our study [26] [39]. This could be explained by the fact that the factors that affect hermetic storage adoption are area-specific and could have been different for Northern Uganda where our study was conducted.