Application of nuclear techniques in drip irrigation to increase food crop yields

According to the FAO (Food and Agriculture Organisation of the United Nations), agriculture accounts for 70% of the use of freshwater resources and it is estimated that by 2050, agricultural water needs will increase by 50%.

The application of isotopic and nuclear techniques makes it possible to know the state and movement of water in soils and therefore to develop sustainable management strategies in agriculture, using cheaper and more efficient irrigation alternatives, such as drip irrigation, which consists of irrigation through a network of narrow pipes or tubes that carry water directly to the root of the plants.

To increase crop productivity, the technique of ‘fertigation’ is increasingly applied, using a nitrogen 15 labelled fertiliser, which determines the efficiency of fertiliser and water uptake by plants and optimises the amounts needed, saving up to 50% of the fertiliser that was used, with the same results, helping to protect people and the environment from pollution by reducing the chances of fertiliser residues leaching into groundwater or contaminating streams or rivers.

Nitrogen 15 isotopes have a different molecular weight than the rest of the fertiliser mixture, making it possible to track them as they enter the soil and plant, and to determine the amount of fertiliser to use and the best application method.

Some examples:

• Kenya: development of a low-cost, small-scale drip irrigation system that increased yields of field-grown tomatoes by a factor of 2.8 using only 45% of the water of traditional hand irrigation.
• United Republic of Tanzania: drip irrigation provided four times higher tea yields than non-irrigated tea grown under rainfed conditions.
• Sudan: Drip irrigation saved 60% of water compared to surface irrigation, increasing onion yields by 40%.
• Mauricio Isle: the use of drip irrigation doubled agricultural production and resulted in large savings in the amount of water used for growing crops, mainly vegetables (almost 80% of the area is rainfed).