My personal opinion is that such vandalism is comparable with instances from history when books were taken from university libraries and burned because someone disagreed with what was written in them.

That was widely and rightly condemned, although it is some consolation that the knowledge contained in those books remained in other libraries. But this is not the case with our trial. By destroying the 400 plants before they had grown and been studied, the knowledge is lost and no-one is any the wiser. To quote Galileo: "All truths are easy to understand once they are discovered; the point is to discover them."

Our research is publicly-funded and involves no financial assistance from business. This rigorous, objective research was funded following a competitive review of the scientific case by a national research council. The field trial came after three years' work and safety was assured after the project was scrutinised by a specialised national committee.

Defra agreed to the trial on the basis of the committee's view, and after considering public views and those of several national authorities.

One aim of the University of Leeds is to create, advance and disseminate knowledge that has an impact on global society. Sadly, the knowledge we were discovering here in Yorkshire was destroyed and lost before this happened.

This is a bigger issue than being either for or against GM crops – or the intervention of Prince Charles who claims multi-national firms are conducting "a gigantic experiment that has gone seriously wrong".

I know of one leading organic farmer who disagrees with my approach but wrote after our trial was trashed to say that its destruction "was an insult to science and an affront to democracy". There is a clear line between the right to legitimate public protest, which our democracy holds dear, and wanton destruction of publicly-funded work.

We were trying to discover if it is possible to control a major pest of potatoes safely without a pesticide. The pest is the pale cyst nematode, a type of microscopic roundworm which occurs in most UK potato fields. Because the species is alien to the UK, there is no widespread naturally-occurring animal or microbial enemies in Britain's ecosystem to limit its populations.

Plant breeding for 50 years hasn't provided a potato line that is fully resistant to it. It is currently controlled with pesticides, with varying degrees of success. They risk environmental harm whereas our approaches do not and they avoid any changes to the tubers we eat.

Potato cyst-nematodes cause extensive damage by feeding on the roots of the potato, limiting the plant's growth. In the UK, they cost farmers around £65m annually in reduced crop yields and pesticide expenses; worldwide, it is estimated that all species of nematodes cost farmers as much as £60bn.

Our research looks at ways of limiting the damage the worm causes and could be of benefit to agriculture not only in the UK, but elsewhere.

A type of cooking banana called a plantain is cultivated extensively by subsistence farmers in Africa, but nematodes cause acute damage to this crop. A food supply sufficient for between 30 million and 50 million Africans is probably lost annually to nematodes on a range of crops.

We already cooperate with government scientists in Africa who use our research findings to improve plantain growth. Again, this work is non-commercial and serves to improve food supply in Africa. Perhaps whoever wrecked our trials in Yorkshire might like to reflect on the benefits this work could have had in Africa.

Vandals were able to locate the trial because Defra is legally required to publish this information. This means that anyone interested is effectively given a map which takes them to within 100 metres of the location.

How can I ensure that future trials can take place without disruption? There are three options. First, each trial site could have a high level of security, but this would probably cost a significant amount. Secondly, there could be a highly protected national testing centre where all trials occur. The third possibility is that the UK follows what happens in Canada, where government allows small field trials of less than two acres to proceed without revealing their location.

The rules are strict; government must be assured that no harm to the environment will occur. They examine the site and require the plants are incinerated at harvest. Further testing proceeds only after full public scrutiny, as in the UK.

I would distrust anyone who argues that all GM crops are either "good" or "bad". We need to look at each on a case by case basis by benefit, crop and country.

But if we do not have rational debate in the UK, we will not gain new benefits, reduce pesticide use and may not ensure that nutritious food is affordable for all in the future. We have a moral duty to deploy our science to help those in Africa and elsewhere.

It is vital that trials take place uninterrupted so that legitimate questions, which the world needs answering about the future of GM, are based on scientific fact rather than speculation.


Howard Atkinson is Professor of Nematology at Leeds University.