2017, July


protezione delle colture dalla pioggia

During the 11th International AIIA Conference held in Bari last month, titled "Biosystems Engineering Addressing the Human Challenges of the 21st Century", a major role was played by the studies and the encouraging results of the tests carried out by the Arrigoni S.p.A. Group on the best solution for the crop protection from rain.

Arrigoni S.p.A is active regarding crop protection from the increasingly frequent heavy rain events. These episodes are consequence of the climate change that is taking place, causing considerable damage to crops.

Fruits such as cherry, kiwi, peach, plum or berries, together with some vegetable crops such as spinach, are subjected to the negative effects of excessive rains such as fungal diseases and fruit cracking (for cherries).

dispositivo di prova

In collaboration with the Universities of Bari and Foggia the Arrigoni research team has shown how the Arrigoni 3532BT PROTECTA 32 fabric can protect the crops from rain damage without compromising its air permeability, which is a guarantee of yield in harvesting many fruits, especially cherries.

So far, the problem of rain protection has been tackled using two practices: chemical treatments and waterproof covers such as plastic film and comparable products.

Chemical treatments reduce the osmotic potential within the fruits; however, their effectiveness is not constant and exactly when intense precipitations occur, the reduction in cracking is, in fact, very low. With chemical treatments, then, the taste of the fruit changes thus involving obvious market consequences.

Plastic films are successful in protection of the fruits from the rains, but they do cause an increase in temperature and relative humidity of the environment that they protect and significantly alter the quality of incident radiation on crops.

The use of HDPE fabrics, specially developed by the Arrigoni laboratory, is then an effective rain protection system that overcomes problems with the use of chemicals and waterproof covers.

For experimental testing on fabrics, a test device was designed and installed to simulate and measure the permeability of agricultural nets to different fabric inclinations with respect to rainfall in terms of reducing the amount of rainwater that can pass through.

The rainwater permeability index of the net is defined as the ratio between the water collected in the container below the net sample and the water totally fed by a rainfall-generating nozzle system. Networks with different geometric characteristics of porosity, textile structure and type of yarn have been tested; the effect of the network's inclination was investigated as well as the real contribution of a double-layer textile system to the decrease in rain permeability.

protezione delle colture dalla pioggia

The results from the 3532BT PROTECTA 32 fabric during the test allow to understand the influence of the main parameters on the rain permeability of the networks.

Porosity can not be directly related to permeability. The size of the mesh, the mesh inclination, and the use of the double-layer scheme of the security system, however, significantly affect the performance.

When a second layer is installed, the system becomes almost waterproof, with a very low rainfall index associated with all the tested inclinations (10% - 20% - 30%).

New studies and tests will be conducted to further investigate the characteristics of all Arrigoni tissues in the interaction with rain, which can be of different intensity and quality; however, thanks to the tests already carried out, the 3532BL PROTECTA 32 fabric solution is evidently effective as well as an improvement over traditional alternatives used to protect crops from rain.