Recently I was able to attend the annual science meeting at the John Innes Centre, and hear about some amazing science going on across the insitute. One talk topic particularly caught my interest- balancing food production with environmental conservation.
Dr Diane Saunders gave a really interesting talk about the delicate balance currently being investigated involving the Common Barberry Bush, the Barberry Carpet Moth, and the cereal disease wheat stem rust- which I am going to share with you in this post.
Balancing food production with environmental costs is a extremely difficult business. Growing enough food to feed our growing population is set to be a massive global challenge over the next few decades, with a estimated 70% increase in food production required by 2050.
As we increase farmland to cope with our ever growing food requirements our natural environment is at risk, and the animals and insects which call those environments home become endangered. There is a delicate balance that needs to be met between food production and environmental conservation. There are many practical and sustainable solutions being developed to help achieve this balance, however, sometimes agriculture and conservation can be completely at odds with each other, as will be discussed for the case of the Barberry bush.
The danger hidden in the hedgerow.
Recently in the UK we realised that the Barberry Carpet moth was under threat of eradication. For years the Common Barberry, Berberris Vulgaris, a shrub of hedgerows and woodlands, was targeted for removal across the UK, which ultimately led to a rapid decline in Barberry Carpet moth populations.
Why was this bush being so widely removed?
The Common Barberry Bush is a host of the cereal disease wheat stem rust.
What is stem rust?
Stem rust is caused by the fungus Puccinia graminis, and is a significant disease affecting cereal crops. Throughout history crop failure and famine has been associated with stem-rust. In western europe we were able to effectively eradicate the disease during the twentieth century, with no cases reported for 60 years, however that all changed in 2013 with a major outbreak of wheat stum rust in Germany. The re-emergence of wheat rust could be devastating to our crops. Here in England, only about 20% of our current wheat variteties are resistant to this new strain of wheat stem rust. Additionally, this new variety of rust is resistant to a lot of our fungicides, preventing us from being able to effectively halt progression of disease through our crops.
Where does the Barberry bush come in?
Historically large scale removal of Common Barberry was promoted to reduce spread of wheat stem rust. The Common Barberry plays a crucial role in the life cycle of wheat stem rust, acting as an alternative host plant for the fungi to infect over winter months. During this period the fungi is able to undergo sexual reproduction which adds to the fungis’ genetic diversity. In order to stop this part of the wheat stem rusts life cycle, the Barberry was removed from all hedgerows across England – which did succesfully break the lifecycle of the fungus, leading to the erradication of wheat steam rust in the UK.
However, removal of Barberry was not without consquences- it dramatically impacted local wildlife, and had a huge detrimental effect on numbers of the Barberry Carpet moth. Caterpillars of the Barberry Carpet moth feed on common barberry, and with the huge reduction of bushes across the country this moth species is now on the brink of extinction.
In a bid to save the Barberry Carpet moth from extinction there have been conservation projects formed to strengthen the remaining populations of the moth in Wiltshire, Gloucestershire and Dorset, which have focused on localised replanting of Barberry. However, with these conservation projects comes a risk of increasing the spread of wheat stem rust.
We do not want to lose a species, and we want to have good diversity of habitats across the country, but we also do not want to be increasing the risk of re-introduction and spread of a crop-disease like wheat stem rust, which has the potential to decimate crops and threat the future of UK cereal crops. So, what are the options?
The problem of the Common Barberry, the Barberry Carpet moth, and wheat stem rust is currently being looked at collaboratively– with scientists (led by Dr Diane Saunders), conservationists, cereal breeders and farmers working together to investigate how habitat conservation can be promoted for the moth without risking our cereal crops.
It is likely that as we continue our push to increase food production futher and futher, we will face more environmental vs agricultural problems, which is why it is more important than ever for scientists, farmers and conservationists to work together.
This type of collaborative project will hopefully enable us a way to not only increase food production for our increasing population, but reduce the environmental impact that we may have on surrounding environments. Unfortunately, in some countries this type of project is not yet feasible due to lack of resources, however hopefully we will see more of these collaborative projects developing in the near future.
References and more reading
A scientist called Erica 