Comparative assessment of the effectiveness of pics and polythene bags in reducing post-harvest losses of green gram: case study Magoro subcounty, Katakwi district

Abstract

In rural Uganda, post-harvest losses remain a major challenge, especially in Magoro Subcounty, Katakwi District, where improper storage, poor handling, and pests reduce crop quality and quantity. Green gram, a key crop in the region, is particularly susceptible to these losses. Effective storage methods are essential for minimizing losses and improving farmers' livelihoods. Purdue Improved Crop storage (PICS) technology and polythene bags have been proposed as potential solutions, but their effectiveness and factors influencing adoption are not well understood. This study aimed to assess farmers' perceptions, the extent of post-harvest losses, and the factors affecting these storage methods, with data collected from 171 farmers and analyzed using SPSS version 20. Results show that, PICS bags were rated significantly higher than polythene bags across several parameters. Farmers rated PIC bags' effectiveness in reducing spoilage with a mean score of 4.3, compared to 2.9 for polythene bags (p < 0.001). Despite this, accessibility and affordability were rated similarly for both types of bags, with no significant difference between the two (p = 0.367). On ease of use, PICS bags were also rated significantly more user-friendly, with a mean score of 4.0 compared to 2.2 for polythene bags (p < 0.001). However, convenience remained a key factor for some farmers, with a preference for polythene bags due to their lighter weight and ease of transport (p < 0.001). Lastly, farmers expressed higher satisfaction with the performance of PIC bags, reporting a mean score of 4.5 compared to 3.2 for polythene bags (p < 0.001). Post-harvest losses in green gram stored in PICS bags were significantly lower than those stored in polythene bags. Storage duration did not show significant differences (p = 0.921), but moisture content was significantly lower in PIC bags (14.5%) compared to polythene bags (16.2%, p < 0.001). Post-storage weight retention was significantly higher in PICS bags (105.6 kg) than in polythene bags (67.9 kg, p < 0.001). No damaged grains were recorded in PIC bags, while significant damage occurred in polythene (32.1 kg, p < 0.001) and combined storage methods (28.3 kg, p < 0.001). Regression analysis explained 51.4% of the variance in post-harvest losses (adjusted R-squared = 0.514). Storage conditions showed a marginally significant positive effect on effectiveness (coefficient = 5.329, p = 0.093), while the duration of storage exhibited a marginally negative relationship with losses (coefficient = -7.197, p = 0.079). However, bag material properties (coefficient = 0.311, p = 0.932) and user practices (coefficient = 1.489, p = 0.682) did not significantly influence post-harvest losses. The findings indicate that PICS bags outperform polythene bags in reducing post-harvest losses, preserving grain weight, and maintaining grain quality. It is recommended that farmers in Katakwi District and similar regions adopt PICS bags for more efficient storage of green gram and other legumes. Agricultural extension services should focus on optimizing storage conditions to enhance the effectiveness of storage technologies. Further research is needed to assess the performance of PIC bags across different agroecological zones to identify best practices for reducing post-harvest losses in varying climatic conditions.