East Malling research finds way to reduce water usage

Thanks to funding from Defra, the team at East Malling Research (EMR) has shown that it is possible to produce one tonne of grade 1 potatoes using just 23 tonnes of water - significantly less than the current 42-60 tonnes industry average for the same yield.

The process was careful use of drip fertigation (fertiliser delivered via irrigation) and scheduled watering. The scientists transferred knowledge gained from earlier experiments that succeeded in reducing water consumption in commercial strawberry production.

The EMR team, led by Dr Mark Else, also increased the yield from the industry standard range of 45-50 tonnes per hectare to 78 tonnes per hectare.

Else said: "We have just lifted the 2010 crop and are confident that we will have improved on last year's yields and, importantly, used less water and fertigation while maintaining the yields and quality of the potatoes produced.

"Given that our trial took place on less than one hectare, we recognise that it will be challenging for growers to replicate these results exactly on a commercial scale.

"However, we have achieved this with our work on strawberries and we believe that the potato trials - now in their second year - demonstrate that with water scheduling and drip fertigation it is possible to dramatically reduce the amount of water and chemicals applied to potatoes commercially.

"As well as saving money for the growers, our trials show that they can increase revenues thanks to a major increase in yields and maintenance of quality."

The team is confident that by the end of the three-year trial in 2011, EMR will have produced a set of guidelines and techniques to help potato growers to use drip irrigation and to know when and how much water to apply.

The guidelines will take into account the actual rainfall and the optimum soil moisture content to deliver the quality and quantity of potatoes expected by growers and supermarkets.

Else added: "There will be a capital investment associated with the techniques, but with good increased yields, maintained quality and lower costs associated with water and chemicals, we believe there is a commercial advantage for UK growers."

EMR head of science Chris Atkinson said: "This experiment has major commercial implications for potato growers, especially those in the south and east of the country that due to less rainfall are more dependent on irrigation.

"It also impacts on the issue of food security because with the climate changing, farmers need to have the techniques to grow more while using less.

"With the population rising and potatoes such a staple part of many people's diets, it is essential that we increase yields and reduce our reliance on imports."

MEETING GLOBAL NEEDS

East Malling Research (EMR) believes its latest work could play an important role in achieving the recommendations made in the Foresight food security report commissioned by the Government's chief scientist Professor Sir John Beddington and published last month.

The report showed that we need to use 40 per cent less water and produce 40 per cent more food globally within the next 20 years.

East Malling Trust chairman Will Sibley, whose organisation is the major funder of EMR, said: "This report, like the many others that have come before it, highlights the scale of the challenges that face the world's ability to feed itself.

"What we urgently need is not more reports, but for Governments across the world to accept the findings and properly fund scientific research that has the ability to increase the intensity of our food production and ensure our food security through higher yields and lower inputs of water, fertiliser and energy."

Currently, 75 million tonnes of water - a quarter of all the water used each year by the agricultural industries in England and Wales - is applied to potatoes.

The intensive irrigation applied by growers helps to reduce the incidence of common scab on the tubers' skin and to increase yields as the tubers form four to six weeks after planting.

This scale of the water consumption is enormous - equivalent to filling 30,000 Olympic-sized swimming pools each year.