biocontrol

Using Bacteria To Swat Malaria Inside Mosquitoes

It’s a bit like probiotics for mosquitoes.

When scientists infect mosquitoes with a specific bacterium, the insects become resistant to the malaria parasite.

Sounds like an easy way to stamp out malaria, right? Just introduce the infected mosquitoes into an area and let the bugs take over the natural population.

But there’s been one big hitch: The bacterium — called Wolbachia — doesn’t stick around inside mosquitoes that carry malaria. So scientists would have to continually release flocks of treated mosquitoes to keep malaria down.

Now entomologists have overcome this obstacle, at least partially.

They’ve created a malaria-transmitting mosquito that maintains theWolbachia infection for its entire lifetime and even passes it onto its offspring.

“Groups have been trying to do this for more than 10 years,” microbiologist George Dimopoulos, from the Johns Hopkins Malaria Institute, tells Shots. “So it’s a landmark achievement.”

The findings, reported Thursday in the journal Science, raise the possibility of one day controlling malaria with the bacteria.

“You could just release large number of infected females and establishWolbachia in a mosquito population” Dimopoulos, who co-authored the study with a team at Michigan State University, says. “Gradually it would convert a malaria-spreading population to a non-spreading one.”

Continue reading.

Image of Wolbachia bacteria, green, infecting the ovaries of the malaria-transmitting mosquito Anopheles stephensi. Courtesy of Zhiyong Xi/Michigan State University

Release the wasps! (no, really, release the wasps) Part I

Today, I released a bunch of wasps into a forest in Wisconsin…

Now tell me what sort of image does that conjure up in your head?

Well, if you’re of my generation (mid-twenties), it might consist of something looking like the image on the left (Beedrill, for those of you not baptized into the church of Pokemon as children, as I was), multiplied into a swarm of sorts, as the bottom image shows.  While this prospect may seem terrifying/exciting/(insert adjective here), I’m going to break it down for you, I did not release a swarm of Beedrill (is that the plural? Beedrill…Beedrills…?  I know, I’m too tangentially worried about Pokemon.) into a nearby forest.  I apologize to any enthusiast who was hoping his or her dream may have come true.  Sorry.

To move back in the direction of more seriousness, you may wonder why I felt it necessary to go into that whole bit about the Beedrill and wanting to catch all the Pokemon.  I must digress.  Many of our perceptions are shaped by the things in which we most commonly associate them.  When I mentioned “wasps,” you certainly may have thought about Beedrill, or “killer” bees (even though they aren’t wasps), or a recent SyFy original movie.  I wish to dispel that notion and enlighten you a little bit (if I may).

 Although we are correct when we call this (Paper wasps, Polistes spp.), and this (Digger wasp, Philanthus sp.), and this (Sapygid wasp, Eusapyga verticalis), wasps, they are by far the “only” wasps.  In fact, the family Braconidae is one of the largest, most highly diverse, family of wasps, with estimates from 50,000 to 150,000 species living today.  One may be incredulous at such a claim, but it is in fact true.  Many of these wasps, especially those that parasitize other organisms, can be very cryptic, or difficult to discern against the background of the outdoors.  Additionally those that are parasitic (termed, parasitoids), spend the bulk of their life cycles inside other organisms, hiding them from only those that know where to look.

If you’re still with me at this point, you’ll notice I’ve highlighted a few things:

(1) I released wasps into a Wisconsin forest

(2) Wasps are a diverse group and

(3) We should not immediately associate the term “wasp” with something that is negative to, or will attack humans

Now that I’ve gotten you (hopefully) to reassess your predisposition to cringe (or run and hide), when you hear someone say, “wasp” (and if you already knew all of this stuff, pat yourself on the back and forgive my slow synthesis), I’d like to introduce you the two wasps that I released into the forest today.

The first image on the right is of Spathius agrili, a parasitoid of the Emerald ash borer (Agrilus planipennis) from China.  Although the picture may make it seem rather large and menacing, it’s actually quite small and docile.  To get a good (general) comparison of the size, take one of your hands and look at your pinky nail; the wasp is slightly smaller than that.  This wasp, being a parasitioid has two goals in life (if I may be so bold and anthropomorphize it): first, to mate, secondly, to find the Emerald ash borer’s larval stage, and lay its eggs on it.  A parasitoid that lays its eggs on an external surface of a larvae is known as an ecto-parasitoid.  In the case of this parasitoid (as well as many others that are ecto-parasitioids-but remember there are always exceptions), it is also known as an idiobiont, which is a parasitoid that paralyzes its host after oviposition-preventing it from moving further.  This makes perfect sense- if a parasitoid lays its eggs on the outside of its host, it does not want the host to be able to move and potentially crush or defend itself against the Spathius agrili larvae consuming it.

The second image to the right is another parasitoid from China that lays its eggs in the Emerald ash borer, Tetrastichus planipennisi.  This wasp is even smaller than S. agrili, averaging the size of a grain of rice.  Unlike S. agrili, T. planipennisi is an endoparasitoid, meaning it lays its eggs inside of the larvae, rather than externally.  Because this wasp does not lay its eggs on the outside of the larvae, it has no reason to paralyze it and prevent it from moving.  In fact, the host larvae will continue to feed (and therefore provide nutrition to the eggs and T. planipennisi larvae) until the eggs inside it hatch and consume its innards.  Parasitoids that employ this non-paralysis strategy are known as koinobionts.

What do you notice about these two parasitoids?

Probably that they have two pointy things that look a lot like stingers.  Let me clarify, those are not stingers.  We are looking at two females both of which have a organ called an ovipositor.  What this organ does is allow a female to direct where she lays eggs.  In the case of these two wasps, they both use it to probe the wood of ash trees until they find an Emerald ash borer larvae, in which they then, lay their eggs.  Let me emphasize again, they is an organ to lay eggs; not sting things.

Another thing you may have noticed, is that unlike the Emerald ash borer, these wasps do not have common names, only scientific ones.  This is a result of them being cryptic (as I mentioned above).  These insects were not named as species (giving them formal scientific recognition) until they were found on a survey that specifically looked for natural enemies (I defined this in my previous post, “In search of native Agrilus”) of Emerald ash borer.  This further emphasizes that this insects are harmless to humans- if it doesn’t sting or bite or provide something beneficial, it can go unnoticed.

The purpose of this post was to introduce you to the wasps that I released today and quell the misconception that every wasp is a bad wasp.  What I will do in the second part of this series is introduce you to the Emerald ash borer and explain why wasps from China are being imported into North America to attack (lay their eggs in) it.

I’m just doing my homework for that interview tomorrow and came across some really interesting research going on in Canada which looks into biocontrol of the Varroa mite using the predatory mite Stratiolaelaps scimitus (previously Hypoaspis miles).

The research suggests that although the predatory mite will not wipe out Varroa infestations, it will greatly reduce their numbers. S. scimitus effectively immobilise Varroa by ripping off their appendages; S. scimitus is small compared to the Varroa mite, so it cannot consume a Varroa mite in its entirety. Use of biocontrol is preferable since chemical control methods can be harmful to the bees occupying the affected hive and repeat use of chemical control agents encourages resistance in Varroa.

Anyway, I recommend giving it a look!

link 1 - article about the research with videos

link 2 - some more info about S. scimitus

On a related note, it seems that pseudoscorpions are also being considered for biocontrol of Varroa and here’s a really knarly video of a pseudoscorpion destroying a Varroa mite (to rock music, because why not)

Bacillus subtilis

“The bacteria [Bacillus subtilis] produce a complex lipopeptide, surfactin that permits them to glide very efficiently over the surface of certain types of media. This property is likely to be related to colonization of the surfaces of leaves (the phylloplane), fruits or sometimes roots.” 

“When conditions become unfavorable, the onset of a differentiation process, sporulation, permits the cells to generate resistant spores that can be easily dispersed throughout the environment where they will germinate if conditions are appropriate.”

“Unlike most other bacterial species, endospore-forming bacteria are highly resistant to the lethal effects of heat, drying, many chemicals and radiation.”

The Worst of the Creepy Crawly Things

I have never spent much time thinking about snakes and bugs, since I was a kid.   My grandma had garter snakes at her house growing up and she never seemed much phased by them, though as small child I was not so sure.   My husband is allergic to spider bites and we had a dog who got a necrotic wound from a spider bite, so even though they do have a purpose we don’t tolerate them in the house or…

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Studies of biocontrol agents yields high results, Special Reports, Phnom Penh Post

By Kali Kotoski Officials from the ministry of agriculture provided an overview for the implementation of the ASEAN national guideline to regulate the trade and use of biological control agents, a step forward for adopting green farming technologies that can increase yields and reduce the damage to crops, while also weaning the country off the dependence of chemical pesticides.

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Spider venom pesticide that has no sting for bees

Spider venom pesticide that has no sting for bees

A pesticide made from spider venom has been found to kill insects without harming honeybees.

Approximately 90 per cent of the world’s plants rely on pollinating insects to survive Photo: Rosemary Calvert/ Alamy

By Sarah Knapton,

Researchers at Newcastle University combined venom from the Australian funnel-web spider and lectin from snowdrops to create a “bio-pesticide”. Common neonicotinoid…

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nylorac15 asked:

The super-focused types of parasites that literally only target the invasive species is the only kind of biocontrol that doesn't freak me out. But I've always wondered what happens if it's actually successful. Does the biocontrol species die off too? Do they move on? Have we even ever *seen* that endgame irl, or is it all theory?

honestly, i don’t know that we have- and parasites are incredibly adaptable critters.  i don’t think there is any species that will just strictly “die off” once it’s done with the invasive- to quote jurassic park, life finds a way.

Left: healthy fungal spore on leaf. Right: destroyed fungal spore after foliar application of Bacilus subtilis QST713.

“Check the exact name of the active ingredient in your chosen B. subtilis product. Keep an eye out for B. subtilis QST713 or MB1600.”

“Some B. subtilis strains also elicit plant health and growth promotion in treated plants. When applied, these strains can trigger your plant’s internal defenses and physiological responses….The effect is systemic - this means that responses are triggered throughout the plant even when just a small area is treated.”

[insert random caption here]💃✨🌟 #kalamazoo #crossword #heteroflexible #biocontrol #random #spunky #seacocks #lingbottom #flexuouse #galatic #incumbent #illuminate #jumbo #bubble #pistachio #love #wishbone #awesomesauce #renton #spoofaloof #tbt Throwback Thursday lol thank you to everyone who participated! 😊😁

Grower Experienced In Biocontrols Says: Be Patient | Growing Produce

Grower Experienced In Biocontrols Says: Be Patient | Growing Produce

The use of biocontrols in all aspects of agriculture is becoming more widespread. But incorporating biocontrols in a vegetable farming operation is an evolving process. Gerry Davis – a Pest Control Advisor, an agronomist for the Crystal Organic Division of Grimmway Farms in Bakersfield, CA, and a presenter at the Biocontrols 2015 Conference & Tradeshow – has worked with biocontrols since the late…

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