Hunting the African armyworm

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My name is Ken Wilson and I'm a Professorof Evolutionary Ecology at Lancaster University and I'm particularly interested in the interactionsbetween parasites and their hosts, and in particular insects.

And my favourite insectis this guy here, the African armyworm, 'Spodoptera exempta'.

And I've been working on this insectfor about 20 years now and what we've been trying to do over the past few years is totry to understand the natural interaction between the African armyworm, a major croppest throughout sub-Saharan Africa, and it's natural disease virus called SpexNPV, alsoknown as Spodoptera exempta nuclear polyhedrosis virus, which is why we call it SpexNPV becauseit's easier to say.

It's December 21, everybody is getting readyfor Christmas, and I am on my way to the airport to catch a flight to Zambia to assess thefood security crisis caused by armyworms.

I've got a busy couple of days ahead of me.

What I am hoping to do is to visit some farmers who have been affected by armyworm, and assessthe impact on food security, I am going to collect some armyworm samples to take backto the UK for analysis, and if all goes to plan I hope to meet with the Vice Presidentof the country to discuss the armyworm situation and what can be done about it going forwardand the role that biopesticides might play in the future.

It's about 20 hours flying time to Zambia so it's 20 hours there and 20 hours back andjust 33 hours in the country, so effectively a day and a half to some work.

Well, I've just arrived in Lusaka.

It's pouring with rain outside, pretty wet and miserable,but being in the tropics I'm sure the rain will go pretty soon and hopefully we'll beable to get out and do some field work.

We're going to go out into the villages andsee what damage armyworm has been caused.

On our way here we've already seen some damagecaused to pastoral grasses, which looks pretty devastating.

We have had a lot of them here just anywhere you see you see them, the armyworms yeah thearmyworms.

So Donald, tell us about this area.

Basically, this whole land was green but the outbreak of these armyworms physically theyare amazing grazers and they've turn the whole land which was green to almost bare, whichis the way it is looking now.

They are brown really.

And these are just reminents becauseif you had come 4 or 5 days ago when it was all green, really there were like all theleafs are covered by these armyworms.

Field where armyworms have attacked.

An armyworm that was not so lucky.

This is what the crop should look like.

Nextdoor, however, it is not so good.

This is Annie Matutu and this is her field.

Tell us what you have done with your field.

So this field, it was affected with the armywormsso what we did we buy cypermethrin then we sprayed all the ground of the field and wedig a trench all around the fields then we started spraying every day in the eveningwe sprayed this trench so that the armyworm can't move into our field and destroy ourmeals.

So you can see this field is looking nicely before we sprayed.

Is the chemical costly? Chemical? It is cypermethrinDoes it cost a lot of money? It was the 150,000 for 2 litres.

Treated with chemicals and not treated with chemicals.

That's all damage caused by armyworms.

Can you show the armyworm? This is a plate infested with armyworm collectedby the children.

So this is Donald my assistant who is carefullypicking out pupae of African armyworm so we can take them back to the UK for scientificanalysis.

So it is 8.


I arrived in Zambia, I haveforgotten how many hours ago.

Start again.

It is 6 o'clock in the morning.

I have beenhere for 24 hours and I am just off to go to see the Vice President to discuss the armywormsituation and what can be done for it to go forward – exciting.

So that was a very good meeting with the Vice President of Zambia and his staff to discussthe armyworm crisis and the things that can be done going forward and we also discussedthe use of NPV as a biological control agent for African armyworms.

The Vice Presidentand his team are very keen to do some trials in Zambia with a view to having NPV availableas a biological control agent against armyworms next time they attack.

It's good to see theresearch paying dividends.

Well here I am at Manchester airport and weare goodness knows how many hours since leaving.

Arrived safe and sound, unfortunately thesame can't be said for my bag which apparently is still stuck in South Africa together withall the samples I collected so it is going to be a little while yet before I can startanalysing those data.

Still, Christmas now.

Well as you can see I got back home safely.

Christmas is upon us.

It's late afternoon on Christmas Eve.

My armyworm samples arestill in my suitcase somewhere over the Sahara Desert but it has been an inspirational trip.

Visiting Mrs Matutu to see the efforts that she is going to to try and project her crops,her livelihood, her family's food from armyworm, at the moment using conventional pesticidesbut who knows in a few years time hopefully available to her will be SpexNPV the biopesticidewe are working on.

Meeting Dr Scott the Vice President of Zambia was also inspirationalin the efforts that his country are doing to try to combat the armyworms in these veryunusual times and it was encouraging to see the level of interest that high level andnational level in the work that we are doing and again hopefully we shall have somethingavailable for these countries to use next time armyworm attack.

It's been a very longweekend over 10,000 miles nearly 40 hours of flying but back home now in the comfortof my home and it is time to forgot about armyworms and to move on to thinking aboutChristmas and getting into the Christmas spirit to drink to the Christmas spirit and havea mince pie or two.

Merry Christmas.

Source: Youtube