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2.2.3.1 Sensors and Diagnostic Devices

In agricultural production, sensors and diagnostic devices allow farmers to closely monitor environmental conditions, plant and animal health and growth.  As part of precision farming they can facilitate targeted and early intervention, thus increasing productivity and decreasing the use of agrochemicals (e.g. antibiotics, pesticides, nutrients). 

Sensors and diagnostic devices are used to measure a number of important variables for agriculture:

• physiological status of crops (such as growth rates, nutritional levels, crop maturity, disease status)
• physiological status of livestock (such as body temperature, respiration rate, blood biochemistry, disease status)
• presence and identification of pests or pathogens
• environmental variables (ambient temperature, levels of water and nutrients in soil)

They are also an essential element in the measuring of the environmental impact of the agricultural process itself, in particular the levels of pesticides and fertilisers in soil and run-off.

The technology already exists to measure each of these variables,however, the technology is not fully optimised for the user.  For example, a measurement usually requires an individual to go physically to the location, obtain a sample and have this analysed at another location (usually an analytical lab).  This process requires technical expertise, is labour-intensive and can take a number of days, by which time the opportunity for optimal intervention could be missed.  By providing robust portable and/or remote in situ sensing and monitoring, backed up with analytical software, farmers can begin to make their own informed choices, in real-time, thus restricting the application of agrochemicals to and limiting the need to acquire technical support only when necessary.

A variety of different sensor and diagnostic systems based on nanotechnologies have potential application in the agricultural industry, these are described in the following sections and are summarised in table 1 below.

Table 1. Different sensor systems which could be used in agricultural production.