
Pesticides are chemicals that are sprayed on potato crops to protect the plants mainly from fungi and insects. Potato yields are compromised if fungi are allowed to grow on the crop and/or insects are left to eat the leaves. Therefore, their use in potato crops is justified. The spraying target for pesticides that are commonly sprayed in potato fields are the potato plants themselves. However, some of the chemicals do end up onto the ground and get absorbed by the soil.
Each pesticide interacts with the soils differently. Most soils will absorb pesticides based on how much organic material is present in the soil. Soils with higher organic matter will absorb more of the chemicals than those with less. Therefore, the likelihood of soil contamination may be characteristic of areas with soils having a substantial amount of organic matter. For other pesticides, the soil’s acidity or alkalinity may affect the degree of absorption of the pesticide.
The absorption of pesticides also affects microorganisms that are contained in soils. Studies show that pesticides may reduce microorganism populations that have soil health enhancement capabilities. Overtime, the soil then loses the ability to hold nutrients. In addition, potato plants benefit from microorganisms as they help turn nitrogen contained in the air into useful plant nutrients. Microorganism absence may result in an increase in fertilizer application – which may be bad for the environment.
The cost-benefit of applying pesticides varies from region to region. Some regions have less insect infestation pressure than others. In terms of fungicide application, some farmers are now using fungal infection prediction sensors in their fields to help reduce how much fungicide they apply in one growing season. However, most farmers do not have these technologies fully deployed due to the potential high risk posed by possible fungal infection. Trial farms have however shown promising results so far.
One way to reduce pesticide contamination and any potential harm to the environment is to develop technologies that detect and deploy them only where and when they are needed. Current technologies limit full adoption from a practical application perspective. There is also growing need to create communication channels between farmers and technology developers. This may result in development of technologies that offer feasible solutions to farmer’s problems.
In my work, I have spent the past two years engaging with different potato farmers in Canada. The farmers have not only shared their problems but have offered possible solutions that they feel are relevant and may benefit them in the near future. One the greatest challenges faced by farmers is the use of technologies that consume more of their time. Consequently, I am developing spraying mechanisms that consider factors such as cost and ease of use. The expectation is to have a complete spraying system that reduces how much pesticides are being applied and therefore decreasing the likelihood of soil contamination.
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