Transcript

FLEA BEETLE! · Cereal Killers

0:02
Hi and welcome back to serial killers the podcast all
0:05
about the pests diseases and weeds and problems
0:08
of arable crops today josie what
0:12
are we covering we are doing the small jumping beetle
0:15
flea beetle phyllo treetop and
0:18
josie has got a lot of material about flea beetle she's got
0:21
four a3 sheets in fact it
0:24
printed off wrong off the printer so it's like four lines
0:27
on four bits of paper so you've done your homework on this one yes i've done
0:31
my homework on this one so how many this was a bit more interesting than grasses
0:35
well yeah it's not hard is it flea beetle how many flea beetles are there in
0:41
the world over 100 species yeah so beetles are the most common,
0:46
common no the most numerous group are on the planet so there's like eight million
0:51
different species well more than plants where there's only 220 000 a lot more
0:57
than let's say mammals where there's hundreds.
1:00
I've got a beetle in my pond. Have you? Yeah, and it just comes up for a bit
1:04
of air, and then it goes down again, and apparently they breathe through their bottom.
1:08
Do they? Hmm. There you go. There you go. So there's, how many did you say,
1:12
flea beetles? Over 100 species. Yeah, and they all...
1:17
Apart from cabbage stem flea beetle, the ones that we're interested in,
1:20
they pretty much have the same life cycle, would you say? Yeah.
1:24
So we treat them all as one?
1:26
Yeah. Yeah. Even though they might have different colourings,
1:28
different, might emerge slightly later or slightly before, they might affect different plants.
1:32
They're all, their control, their life cycle will be very similar.
1:35
Yeah. We're particularly interested in the oilseed rape.
1:40
Flea beetles. Yeah. Yeah. Anything on a brassica, basically.
1:43
That's right. I think phylotetra is the genus. There's about eight species of them on brassicas.
1:48
You're not going to get flea beetles that are going to cause major issues on cereals.
1:52
No, but there is a flea beetle that affects flax.
1:56
There is the flax flea beetle. Very problematic. And if you walk through a flax
2:02
field, you'll get loads of flea beetles jumping around.
2:05
And there's a potato flea beetle, epitrix. Okay. And if you find that,
2:10
you have to notify DEFRA or FERA or the Plant Health Inspector or whatever they're
2:14
called that week. Is it new then to the country?
2:17
No, it's been around for a while, but it's just one of those notifiable pests.
2:20
Okay. Yeah, I think it's big in Italy. There you go. Oh, is it?
2:23
Yeah. So, you know, we have to mention you being Italian on every podcast.
2:27
We've got a tenuous link going on here. Give us a potato dish from Italy.
2:33
There you go. Are there any major ones?
2:36
What's... Gnocchi. Gnocchi, yeah. There you go. Everyone loves gnocchi.
2:39
There you go. So we're talking particularly on the crucifers, the brassicas.
2:45
And unlike cabbage stem flea beetle, it's the adult that causes most of the
2:48
damage. I'm going to... Like shot leaves, aren't they? Yeah.
2:52
Like... Shot holes in leaves. Or they might not get all the way through and
2:56
they're still just like craters.
2:58
Yeah. Yeah, it can get like a nice lacy appearance on your leaves. Yeah.
3:03
And the larvae can mine the leaves as well on the outside or the stem a bit.
3:08
So a lot of beetles do mining larvae, but this one's on the outside.
3:12
Yeah. How big is a flea beetle?
3:14
It is one sixteenth of an inch. They're literally tiny. My heart sinks every
3:19
time you give me an imperial measurement.
3:21
Two to three millimetres. There we go. Shows you how old I am. Oh my God.
3:26
I know. I better change my mindset pretty quick there. i just
3:30
you know you but
3:32
you had yes get on the metric all our kids have been taught metric and then
3:38
they leave school and they have to go back into 16th of an inch or it just keeps
3:42
them awake yeah right so but they've got large rear legs despite being so tiny
3:49
they've got their back Blacklegs are big.
3:51
I read well-developed rear or hind legs.
3:56
So they jump like fleas, but they're not. They're a beetle.
4:00
Yeah. So not to be confused with a flea. In German, they've got some name that
4:04
means ground flea, I think, or soil flea.
4:07
I don't know what that is in German. No, I don't. A-H-E-C-S-E,
4:10
German. No. But these aren't.
4:13
These aren't harmful to us, whereas fleas will kind of bite or sting us.
4:18
These don't. No, they just jump into your leg. That's about as bad as you're
4:22
going to get unless you're a farmer when they're taking your yield away.
4:24
How bad is it on a yield perspective?
4:27
In 2020, an average of 31% of drilled area for oilseed rape was lost to flea
4:35
beetle damage. But was that cabbage stem flea beetle?
4:38
No, that was oilseed rape. No, but it still might be cabbage stem flea beetle.
4:43
Oh no, I don't know that one. We'll look into that one. Yeah.
4:46
In the south of England, 41% of oilseed rape was written off.
4:51
And east of England, 37%. And that was four years ago.
4:55
Because we're going to do a separate podcast on cabbage stem flage.
4:57
Yeah. We're going to do a deep dive. Fun, yeah.
5:00
To the deepest depths. There we go.
5:04
So there's a lot of information on companion planting and trap crops.
5:08
Some of it anecdotal, some of it evidence-based. So a companion crop is something that dissuades.
5:14
Oats are a companion crop? Yeah, that would dissuade it from coming in.
5:19
So the beetles might land on it, realise it's not a crop and then fly away.
5:23
Trap crops are ones that draw them in. Yep, sacrificial crops. Sacrificial crops.
5:28
And one of the key things about flea beetles is that for a beetle,
5:31
they're actually very good flyers. They can fly a long way.
5:34
They just don't fly very high. Do they fly or do they jump? They fly.
5:38
Oh, do they? Yeah, they're a beetle, they fly. fly but they can
5:42
fly a long way but they don't fly very high
5:45
so things like fences or
5:49
or fleecing yeah can
5:52
can stop them maybe they're just above like a meter or something
5:55
okay so in my greenhouse i
5:57
grow chinese cabbages and i
6:00
can leave the top vents open and i'll never get
6:03
any flea beetle damage okay and chinese cabbages are
6:06
a great crop to grow in a greenhouse because they'll grow like
6:09
stink and as long as you can keep flea beetle off them they'll grow really
6:12
well i like cabbage outside chinese cabbage
6:15
is a whole different story i know destroyed by i like pak
6:17
choy and things like that i've stopped growing it yeah but yeah get yourself
6:21
just buy a greenhouse you know i have got greenhouse i'm going to try that try
6:25
it there you go do you cook your chinese cabbage or do you eat it like oh yeah
6:29
yeah boil it in a stew boil it yeah oh my god you mean gently braise Is it?
6:35
No, no, stick it in with like udon noodles and bacon. Okay, all right,
6:39
then I'll let you go on. Sichuan pepper.
6:41
My wife doesn't like to cook it very often. She doesn't like Sichuan pepper.
6:45
Anyway, back to Flea Beetles. There's a few sort of...
6:50
Things that have been looked at for controlling them other than just insecticides.
6:53
So like wormwood extract has been looked at as a control method. Artemisia, that is.
6:59
Isn't that what's used to make that drink that's really strong and green?
7:04
Yeah, absinthe. Yeah. And it's an interesting one because it was considered...
7:08
So if you look at Utrema's portfolio of products, a lot of them are classed as basic substances,
7:13
which is a term used by the
7:16
European Commission to classify very simple
7:19
compounds that can be used for pest and
7:22
disease control in crops that don't require to be
7:25
registered as pesticide and artemisia wormwood
7:28
extract was one of the ones that was considered and they
7:32
made a judgment that while it's possibly very safe it wasn't safe as all the
7:37
other basic substances like chitosan or bicarb or beer or yeast and things like
7:44
this and so it wasn't registered as a basic substance.
7:49
So that wasn't allowed for control.
7:52
Other methods of control, I guess, insecticides where they can be used.
7:56
They're becoming resistant to pyrethin sprays. Yeah.
8:00
Parasitic wasps love beetles and their larvae. Oh, good. So for every pest there
8:05
is one. Nematodes. Nematodes are good.
8:07
Are they? Yeah. If you can apply them. So are arable crops probably not possible.
8:13
What I found interesting about the Flea Beetle is that,
8:17
They lay their eggs. The adults emerge. They can fly up to a kilometre.
8:21
They lay their eggs. And then they live for two to three weeks. And then they pupate.
8:26
And that pupation takes six to eight weeks, which is a long time, I think.
8:32
Well, it's just developing their back legs, isn't it? So that they can go around
8:36
jumping around. Takes so long to develop those back legs.
8:39
Yeah. The adults emerge, start eating, producing their shot holes.
8:42
And then they overwinter as adults in the soil. and that's
8:45
quite unusual because most insect pests either overwinter
8:49
as a pupa you know you think
8:52
about thrips and things like that they'll overwinter as a but they
8:55
like shelter spots so your field margins and your hedgerows yeah
8:58
they eat the crop and then they go right it's time to go away now yeah
9:01
and then leaf litter as well so but then
9:04
they'll come back in the spring yeah and i think that's
9:07
probably one of the issues we had we tried to do a flea beetle
9:10
probably a cabbage stem flea beetle control where
9:14
we're looking at using something called lime sulfur and the problem is that
9:19
unless you've got residual activity on the crop it's really hard to control
9:24
and do a trial on flea beetle because you could kill off all the flea beetles
9:29
in a five hectare plot and then,
9:32
they'll all just come in from the crops because they can fly for such a long distance they can
9:37
smell the crop right yeah so they've been to their winter residence yeah so
9:42
multiple applications are required things like that it's going to be one that's
9:45
going to affect young crops because.
9:48
Obviously if you get a bit of adults feeding on an adult crop it's not going
9:51
to be a big issue whereas a young plant will take away the cotyledons well the
9:57
larvae feed on roots and the entire stem so that's more cabbage stem flea meat
10:01
i think is where this the stem is destroyed yeah but feel Feel free to correct
10:05
me if you know different.
10:07
So spring-sown brassicas is a key issue here for standard flea beetle.
10:14
Any, another interesting fact about flea beetles is that they,
10:18
in America, they've introduced flea beetles to control spurge weeds.
10:24
Oh, right. So, euphorbias. Yeah. And things, so, can be, they can be beneficial
10:29
if they're feeding off weeds.
10:33
Wow. So, we just need, so, like, if you found a groundzool. You need to watch
10:37
that one, then. Yeah. See how that goes.
10:39
Yeah, like ragwort, you get flea beetle on day. Oh, right.
10:42
Yeah. since 2013 the
10:46
oilseed rape harvest has fallen by
10:49
50 due to flea beetle yeah so
10:53
flea beetle and cabbage stem flea beetle together in 10
10:56
years yeah it's a it's a hit or
10:58
miss crop yeah in a lot and and i think depends on what the crops are doing
11:03
in different parts of the world as well what whether the price is obviously
11:07
a big issue one issue as well is because they can fly along long distances but
11:12
there is control methods for them there was a proposal that everyone on the,
11:18
east of the penance would grow oilseed rape
11:21
one year and then everyone on the other side of the penance should grow
11:23
the next year and you could potentially wipe it out if you did that but
11:27
that requires all the farmers to work together and agree who's going
11:30
to grow oilseed rape and i don't think that would ever be just
11:33
really possible but also drape is a really important crop
11:37
yeah you're basically asking you know 20
11:40
000 ceos to all agree yeah so it's virtually impossible and we're looking at
11:46
other oilseed crops here at utrema so if you are fed up of your oilseed rape
11:53
being destroyed and you're looking for something that's more reliable and has
11:57
a more guaranteed income.
12:00
Then get in contact with me at russell at utrema.co.uk we're
12:04
actively looking for farmers to trial a different oilseed
12:07
crop with some of our commercial partners and particularly
12:10
looking for farmers down in the southeast of england but even
12:14
if you're not in the southeast of england please do get in contact i've got
12:17
something just to finish up with that's quite
12:20
interesting about them gone so they jump
12:23
when they're threatened and they can do over 30
12:26
consecutive jumps right okay and
12:30
because their large rear
12:33
legs are really effective in nature
12:36
scientists are looking at this catapulting junk mechanism in the flea beetles
12:42
and looking at what's the word reproducing it yeah in robotics as well as in
12:50
engineering and industrial installations,
12:54
and it's looking at they're also looking at creating a bionic limb yeah using
13:00
this technology so i've got a question for you come in who would win at the
13:06
insect olympics between a click beetle and a flea beetle.
13:12
Does original height take into account there
13:15
you go the flea beetles
13:17
are tiny so the click beetle's got
13:20
a bit of an advantage because they're bigger so they can jump further yeah yeah
13:25
so there you go click but i think flea beetle give it a run for its money with
13:29
over 30 consecutive jumps there you go so so the click beetle would win the
13:34
high jump yeah but the flea beetle will win the The triple jump?
13:40
I don't know. There you go. I was going to say hop, skip and a jump there. Yeah, probably.
13:44
Brilliant. But this is like using nature. Yeah.
13:48
There you go. Brilliant. On that absolutely amazing fact there from Josie,
13:53
any other interesting jokes or facts?
13:57
No. No. There you go. There's some joke in there about John Paul,
14:03
Georgia or Ringo as well, but I've not had time to think about it. Oh, okay.
14:08
Okay there you go but yeah on that useless drivel that has petered out into a boring conversation,
14:16
we all end the podcast thank you very much thank
14:19
you i enjoyed that one yeah what do you want to do next i think
14:22
ryegrass no i think we should do cabbage stem flea beetle i haven't done that
14:26
one yet i know but the listeners don't know that oh yeah we'll do yeah ryegrass
14:30
and cabbage flea beetle there you go yeah okay both of these are going to be
14:35
coming up very soon brilliant make sure you You hit that bell icon so you know.
14:40
And tell us what your favourite pasta and chocolate bar is.
14:44
And who would win in your insect Olympics.
14:47
Yeah. All right. Until next time. Thank you very much. Thank you. Ta-ra. Bye.
14:52
I wonder if anyone will get in touch with us. Probably not.