Profitable chemical-free cowpea storage technology for smallholder farmers in Africa: opportunities and challenges

Cowpea is the most economically and nutritionally important indigenous African grain legume, grown by millions of resource-poor farmers. It is a key cash crop in areas too dry to grow cotton or other export crops. Most of the over 3 million t of cowpea grain produced annually in West and Central Africa is grown on small farms. Storage is often identified as the key challenge for small scale cowpea growers. Many farmers sell cowpea grain at low harvest time prices rather than risk losses by bruchids during storage. Some traditional methods are effective for small quantities (e.g., 10 kg), but are difficult to scale up. Some effective storage chemicals are available, but they are regularly misused by farmers and merchants. The Purdue Improved Cowpea Storage (PICS) Project is addressing these problems through promotion of hermetic storage in triple layer sacks which have an outer layer of woven polypropylene and two liners of 80 μ high-density polyethylene. Village demonstrations with more than 45, 000 PICS sacks have shown the technology to be effective. Good quality affordable sacks have been produced by manufacturers in Nigeria, Burkina Faso and Mali. Over the past three years more than one million sacks have been produced and sold. Despite the success with the outreach activities and the farmer adoption, the challenge remains to develop sustainable sack distribution networks. Issues identified include reluctance of wholesalers to order sacks due to risk associated with a new product, inability of wholesalers to develop effective distribution networks due to difficulties with enforcing contracts, and limited access to capital. The PICS project is exploring new ways to address some of these issues, including using non-traditional distribution systems for PICS sacks such as agro-dealers networks, and adapting distribution systems that have worked for cell phones and other products. Keywords: Cowpea, Bruchids, Hermetic storage, Supply chain, West and Central Afric

Grain Handling and Storage in Lubero and Rutshuru Territories in the North Kivu Province, the Democratic Republic of Congo

Postharvest management of grain and seed is a challenge among smallholder farmers. Limited information is available on how smallholder farmers in eastern Democratic Republic of Congo (DRC), who have been exposed to multiple conflicts, manage grain and seed after harvest. We interviewed 690 smallholder farmers in Lubero (Baswagha chiefdom) and Rutshuru (Bwisha and Bwito chiefdoms) territories of the North Kivu province of the DRC to assess how they dried and stored their crops. Results reveal that 95% and 80% farmers produced beans and maize, respectively. About half of respondents in Bwisha grew soybean, suggesting production diversification using conflict-resistant crops to minimize thefts and looting. Rotting and theft were the major challenges during field drying, while insects (81.3%) were the most important issue during storage. Sixty-six percent of farmers did not protect their grain during storage, exposing it to insect damage. Farmers producing beans in both Bwisha and Bwito, farmers storing beans and maize, and those storing for more than three months were more likely to protect their grains during storage. More than 70% of farmers saved seed for planting the next season but suffered significant weight losses of up to 50% due to insects. Storing grain in hermetic bags for six months had an estimated return on investments of up to 63% for maize in Baswagha and 54% for beans in Bwisha. Improved drying and storage technologies would help smallholder farmers to reduce their grain postharvest losses due to mold, theft, and insects. Smallholder farmers using these improved postharvest technologies have the opportunity to secure quality grain for home consumption and sale, and seed for planting

Coffee Storage in Hermetic Bags and its Influence on Prices and Sensory Scores

Coffee quality is generally evaluated through cupping, a technique based on sensory perceptions. Trained cuppers assign scores to ten quality attributes on a scale of 1 to 10. Exposure of coffee to moisture and/or oxygen during storage and/or transportation can affect the sensory evaluation and reduce the price received by farmers. This pa-per has two objectives. First, it estimates the effect of sensory scores and water activity on coffee price and its price differential from the market price. Second, it explores coffee sensory scores sensitivity to storage duration and water activity under two methods of application of the Purdue Improved Crop Storage (PICS) bags - the standard three layers PICS bag (PICS-3L) and the two layers PICS bag (PICS-2L). Data were collected for ten months from an experiment conducted in Man-izales, Colombia. Results suggest, on average, that an additional point in the score of flavor or body increases the price of coffee by at least 66 COP/kg (0.015 USD/kg). If coffee has an additional point in aftertaste or uniformity from what is expected from other coffees of the same origin, then its price differential is reduced by at least 8 COP/kg (0.002 USD/kg). Using a PICS-3L bag instead of a PICS-2L bag does not affect the coffee price or sensory scores, but it reduces the price differential by approximately 18 COP/kg (0.004 USD/kg). On the other hand, wa-ter activity reduces coffee price but not its price differential. Storage time affects coffee sensory scores in some attributes, which may im-pact the coffee bean price

Management lessons learned in supply chain development: the experience of PICS bags in West and Central Africa

In order to facilitate the transformation of African agriculture, Africa’s smallholders will require more and better access to input markets that deliver context-specific and well adapted innovations. This article summarizes the management lessons learned in developing supply chains for Purdue Improved Crop Storage (PICS) bags in West and Central Africa. PICS bags are hermetic grain storage bags that are leading a revolution in the post-harvest handling of grain on smallholder farmers in Africa. The bags have been very popular with farmers, but the major challenge has been developing supply chains to make those bags available for purchase at the village level. This article: (1) describes the PICS supply chain in West and Central Africa; (2) identifies constraints (i.e. financial, structural, social) that impede the development of the PICS supply chain; and (3) analyzes strategies used by businesses to expand distribution channels and increase bag sales

Effects of PICS bags on insect pests of sorghum during long-term storage in Burkina Faso

The PICS bags, originally developed for cowpea storage, were evaluated for sorghum (Sorghum bicolor) preservation. Batches of 25 kg of sorghum grain were stored in 50 kg PICS or polypropylene (PP) bags under ambient conditions for 12 months and assessed for the presence of insect pests and their damage, seed viability and, oxygen and carbon dioxide variations. The grain was incubated for 35 days to assess whether any insects would emerge. After six months of storage, oxygen levels decreased in the PICS bags compared to polypropylene bags. After 12 months of storage, only two pests, Rhyzopertha dominica and Sitophilus zeamais were found in the PICS bags. However, in PP bags there were additional pests including Tribolium castaneum and Oryzeaphilus mercator and Xylocoris flavipes. Grain weight loss and damage caused by these insects in the PP bags were significantly higher compared to those stored in PICS bags. Germination rates of sorghum grains stored in PP bags decreased significantly while no changes were observed in grains stored in PICS bags when compared to the initial germination. After the incubation post storage period, there was a resurgence of R. dominica in sorghum grains from PICS bags but the population levels were significantly lower compared to polypropylene bags. PICS bags preserved the quality and viability of stored sorghum grains and protected it from key insect pests. The PICS technology is effective for long-term sorghum storage but the potential resurgence of insects in low-oxygen environment calls for further research

Comparative performance of five hermetic bag brands during on-farm smallholder cowpea (Vigna unguiculata L.Walp) storage

Cowpea (Vigna unguiculata L. Walp) grain is an important source of protein for smallholder farmers in developing countries. However, cowpea grains are highly susceptible to bruchid attack, resulting in high quantitative and qualitative postharvest losses (PHLs). We evaluated the performance of five different hermetic bag brands for cowpea grain storage in two contrasting agro-ecological zones of Zimbabwe (Guruve and Mbire districts) for an 8-month storage period during the 2017/18 and 2018/19 storage seasons. The hermetic bag treatments evaluated included: GrainPro Super Grain bags (SGB) IVR™; PICS bags; AgroZ® Ordinary bags; AgroZ® Plus bags; ZeroFly® hermetic bags. These were compared to untreated grain in a polypropylene bag (negative control) and Actellic Gold Dust® (positive chemical control). All treatments were housed in farmers’ stores and were subjected to natural insect infestation. Hermetic bag treatments were significantly superior (p< 0.001) to non-hermetic storage in limiting grain damage, weight loss and insect population development during storage. However, rodent control is recommended, as rodent attack rendered some hermetic bags less effective. Actellic Gold Dust® was as effective as the hermetic bags. Callosobruchus rhodesianus (Pic.) populations increased within eight weeks of storage commencement, causing high damage and losses in both quality and quantity, with highest losses recorded in the untreated control. Cowpea grain stored in Mbire district sustained significantly higher insect population and damage than Guruve district which is ascribed to differences in environmental conditions. The parasitic wasp, Dinarmus basalis (Rondani) was suppressed by Actellic Gold Dust® and all hermetic treatments. All the hermetic bag brands tested are recommended for smallholder farmer use in reducing PHLs while enhancing environmental and worker safety, and food and nutrition security

Integrated Pest Management Resources

WorldAgInfo Project Literature Revie

Assessing the Private Sector’s Efforts in Improving the Supply Chain of Hermetic Bags in East Africa

Hermetic bags are effective at curbing grain losses due to insect pests, but their use remains low due to unavailability among smallholder farmers. This study used primary data from actors within the Purdue Improved Crop Storage (PICS) supply chain network, mostly the private sector, in Ethiopia, Tanzania, and Uganda, to understand the challenges and opportunities in improving the availability of hermetic bags in rural areas. It finds that supply-side distribution approaches played a critical role in improving PICS bag availability. Some of the supply-side constraints included poor inventory management, pricing, and limited access to capital. Inventory management can be improved through better forecasting using sales records and prediction of farmers’ harvests. Improved access to credit during peak season can improve the timely supply and reduce stockouts. Marketing inefficiency appears to be fueled by a high-profit margin at the distributor level. Using all available distribution channels in addition to ag-input dealers will enhance the availability of the bags in rural communities