Latest / Hydroponics Daily / Whitefly Secrets Part 2 : Life Cycle, Damage & Control

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Whitefly Secrets Part 2 : Life Cycle, Damage & Control · Hydroponics Daily

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  Hello there, and welcome back to Hydroponics Daily, your go-to podcast for everything
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  soilless cultivation. I'm your host, Dr.
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  Russell Sharp, and yesterday's podcast was all about whitefly,
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  and I thought I'd actually continue the theme and talk about whitefly again,
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  because I forgot to mention their unusual life cycle.
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  I did mention I'm watching Alien Earth, the series based on the alien films
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  and very similar life cycle except there's no face huggers when it comes to whitefly.
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  So he said that whitefly are true bugs. They belong to the same type of insects
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  as aphids, the hemiptra, and they feed on plant sap just like aphids.
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  They're very small like aphids but probably not as small as an aphid.
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  So they have powdery white wings that make them look like tiny, tiny moths.
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  The crucial thing here is that females lay the eggs on the underside of plant
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  leaves, whereas an aphid can give birth to live young, even pregnant young.
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  And they often are on the stems.
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  They will be on the underside of leaves as well, but whitefly are exclusively
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  pretty much under the underside of the leaves.
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  And these eggs hatch into mobile crawlers
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  after six days so these are wingless sort
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  of funny looking insects and they
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  stay on they remain in the same location these nint
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  these eggs these crawlers stay there
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  for maybe up to six days once the crawlers find
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  somewhere to feed on the plants they lose
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  the ability to walk they lose their ability to walk and
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  they eventually form a scale so a
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  bit like scale insects but not as big not as large and
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  not as strong not as powerful and as structurally sound
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  but they they are related to scale insects so
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  they form this scale and they remain in place
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  throughout the immature development so about 16 days for that so much longer
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  you won't be able to see these unless you're really looking for them and that's
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  why you need to get in there with a hand lens they then pupate in the scales
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  and emerge as winged adults from the nymphal case and leaving empty skins.
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  You'll see these, the scientific names for the empty skin is the ex-vue on the leaves.
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  So you'll be the, even if you've no longer got whitefly, you will still see
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  the remains of the pupil cases. That's very different to.
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  Something like a thrip where the pupas fall to the soil.
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  And so you are able to control white fly if you spray the underside of the leaves.
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  Whereas with thrips, a whole part of the life cycle is somewhere else in your
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  grow room or your greenhouse.
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  And then the adults can live to up to three weeks and often found in mating pairs.
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  And the females are larger than the males. So that's interesting that they hang
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  around in pairs. Isn't that lovely?
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  Loved up white fly. And then obviously a
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  female can lay about 100 eggs in her lifetime often
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  in fairy rings so you'll find those in
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  circles on the undersaddle leaves so you need
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  to be able to differentiate what those look like compared to say ladybird or
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  other beneficial insect eggs okay obviously the times that they take to develop
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  those times groted will vary depending on the the temperature of which they're
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  growing and also the species.
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  There are over 1,500 species of whitefly and most of them are inconspicuous
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  and never reach densities high enough to cause damage to host plants.
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  There's a few species that are major pests and so Bermesia tabaccai,
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  the sweet potato whitefly, is a very common one.
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  The greenhouse whitefly is another one and so they're all in that Bermesia genus,
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  the ones that cause problems.
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  We said yesterday that they cause problems because they suck the sap,
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  the energy, the life force out of the plants.
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  They can also excrete honeydew, just like aphids can, which can cause black,
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  sooty mould on your plants.
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  Very, very damaging to crop quality and appearance.
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  And all of the insects in the Hemiptera, so aphids, scales, whiteflies.
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  What's the other one? I can't think of it.
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  The one with like the powdery white stuff on
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  that'll come back to me they all transmit viruses so they
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  all transmit hundreds of viruses so another good
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  reason to control white flies if you get an infestation or
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  even just a few plants infected or with just a few
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  white fly mealy bugs i didn't
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  have to google that i just had to think for five seconds mealy because
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  the other type of insect in that in that insect family
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  then finally one thing we didn't mention yesterday that
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  is also important for aphids is that if
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  you finish a grow don't leave a few plants
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  in there give it a good couple of
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  weeks to prevent a green bridge from forming this
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  will mean that any adult whiteflies need to be
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  on a host they'll die after a day or so off the
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  plant without feeding the eggs if they're still
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  if you've got grow media you might still have eggs or
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  even pupa especially you've got dead plant material there
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  so if you can remove the grow media and any
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  living plant material that will help form a gap in
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  the growing period that could help control whitefly aphids
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  and any other sort of pests in that family the
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  hemiptera so it doesn't work for other things like thrips because the pupa will
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  be on the ground and things like this but it will work for these sorts of insects
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  in most cases we have some issues where we we removed all the plants but there
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  were still obviously eggs in
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  the soil and so we've got reinfection of our grass plants with aphids but.
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  Hopefully you know you'll get less starter material if you if you remove that green bridge,
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  whilst we say what else has been going on as i've been working on microgreens.
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  Got some really good microgreen trays they're like green trays
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  with white inserts and a clear
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  plastic propagator on top you can buy these on
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  amazon and other places they're really good but they're designed
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  to have soil in and or grow compost and
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  i'm trying to go for a compost free microgreens production you
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  find on youtube a lot of the microgreen growers are grown
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  with compost i want to do a full hydroponic microgreen setup
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  and they come with pieces of paper you're supposed
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  to grow the seeds on with your fertigation solution i
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  have basically found that these pieces of paper are rubbish because you basically need
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  to be there every four hours to re-wet them
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  which is no good so i've decided to set up
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  a system where i've cut a big slit in one
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  of the trays one of the holders one
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  of the sieves and i've i've got
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  um white towels that i've cut up and then i'm using that to wick the the fertigation
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  solution from the reservoir at the bottom up to where the seeds are being held
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  on the on the matrix so i'll report back on whether that was success but i've
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  got high hopes for this i think this is going to be a good way of micro.
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  Micro green growing that involves hydroponics because
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  at the moment most of the hydroponic growers they're just
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  using their cocoa or or just
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  compost standard compost it's not really hydroponics so let's see if we can
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  get a simple no pump microgreen production setup if you've grown microgreens
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  without compost or coir even then let me know got any tips i'd be very very
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  glad to receive them that's been hydroponics daily for today the life cycle of the white fly,
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  as i say very they don't look nice either these these nymphs these crawlers
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  and especially when they pupate it does look very much like an alien especially
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  with the eggs in a circle very sinister,
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  very much like the alien xenomorph life cycle from the alien movies have a look
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  into that it's good good it's a good watch all right thank you very much for
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  listening for today and i'll see you again tomorrow with more exciting topics
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  on hydroponics daily goodbye.