Spatial arrangement of silo bags is key to mitigate damage by wildlife

BACKGROUND

Silo bag is a major harvest storage option in many countries worldwide. Wildlife interacts with this new element in the rural landscape. As a result, wildlife activity could generate breaks in silo bag lining, causing losses to the stored content. The aim of this study was to analyze the damage in silo bags by large hairy armadillos (Chaetophractus villosus) according to different spatial arrangements of silo bags, in order to propose a management strategy to reduce the damage. Our prediction was that silo bags arranged in a cluster would have less damage by large hairy armadillos than bags arranged in a row or than single (isolated) bags at a certain plot. In addition, we expected that in a cluster the exposed outside of the bags would show increased damage compared to the inside of the cluster.

RESULTS

We measured 294 silo bags. Damage intensity (number of breaks/100 m silo bag perimeter) in silo bags arranged in a cluster was 72% lower than in bags arranged in a row (P = 0.03), and 77% lower than in single bags (P = 0.001). Moreover, we detected that damage intensity inside was 75% lower than outside of a cluster (P = 0.001).

CONCLUSION

We propose grouping in a cluster of parallel bags instead of installing them in a row or isolated bags at plot as a strategy that could be adopted and implemented by farmers in order to reduce the damage by large hairy armadillos, the most harmful wildlife species to silo bags in Argentina. © 2021 Society of Chemical Industry.

Natural Drying of Astringent and Non-Astringent Persimmon "Rojo Brillante". Drying Kinetics and Physico-Chemical Properties

Persimmon (Diospyros kaki L.f.) crop has markedly increased in Spain, and “Rojo Brillante” persimmon is the main cultivated variety. This astringent cultivar requires de-astringency treatment before commercialization, which may involve an extra cost. Its short commercial season implies handling large volumes of fruits with consequent postharvest losses. Therefore, the development of derived added-value products is of much interest. In this study, astringent and non-astringent “Rojo Brillante” persimmons were dehydrated by following a natural drying method used in Asia. The drying kinetics and physico-chemical properties were analyzed for 81 days. The results indicated subsequent reductions in weight, water content, and water activity throughout the drying process, and the equatorial diameter decreased. All the employed thin-layer mathematical models were suitable for representing the drying characteristics of both products with similar behavior. The effective water diffusivity values were 5.07 × 10⁻¹¹ m² s⁻¹ and 6.07 × 10⁻¹¹ m² s⁻¹ for astringent and non-astringent persimmon samples, respectively. The drying treatment significantly decreased the soluble tannins content, and the astringent samples obtained similar values to those obtained for the non-astringent samples in 20 days. The external and internal flesh of the astringent fruit remained orange through the drying period, while brown coloration in the non-astringent fruit was observed after 57 drying days. Therefore, prior de-astringency treatment would not be necessary.

Efficacy of Management and Monitoring Methods to Prevent Post-Harvest Losses Caused by Rodents

The presence of pest rodents around food production and storage sites is one of many underlying problems contributing to food contamination and loss, particularly influencing food and nutrition security in low-income countries. By reducing both pre- and post-harvest losses by rodents, millions of food-insecure people would benefit. As there are limited quantitative data on post-harvest rice losses due to rodents, our objectives were to assess stored rice losses in local households from eight rural communities and two rice milling factories in Bangladesh and to monitor the effect of different rodent control strategies to limit potential losses. Four treatments were applied in 2016 and 2017, (i) untreated control, (ii) use of domestic cats, (iii) use of rodenticides, (iv) use of snap-traps. In total, over a two-year period, 210 rodents were captured from inside people's homes, with Rattus rattus trapped most often (n = 91), followed by Mus musculus (n = 75) and Bandicota bengalensis (n = 26). In the milling stations, 68 rodents were trapped, of which 21 were M. musculus, 19 R. rattus, 17 B. bengalensis, 8 Rattus exulans, and 3 Mus terricolor. In 2016, losses from standardised baskets of rice within households were between 13.6% and 16.7%. In 2017, the losses were lower, ranging from 0.6% to 2.2%. Daily rodent removal by trapping proved to be most effective to diminish stored produce loss. The effectiveness of domestic cats was limited.