Mosquito larvae in pitchers - any conclusions?

[jixxxs]

Guys/gals,

i know there is a sticky on this subject, But where there any conclusions..?

As in are our Neps larvae killers as well or should we be concerned about breeding killers..?

Asking cos with the rain season and all those dengue cases in Selangor.. i sure don't want to be contributing to the problem....

[shamrock]

will sprinkling Abate into the pitchers be harmful to the plant or pitchers?

[NepNut]

I only once discovered mossy larvae in one of my nep. The pitcher that support the mossy larvae was actually an old pitcher filled with water.

So, I would suggest cutting any old pitchers that started to collect water in it's pitcher.

[marvin1997]

Or just pour them out?Sometimes it's just confusing when my nep pitchers has no water although it's not dead and there's alot of ants in there.I thought they don't absorb all the juice??

[Charles]

Hi All,

It's nice to see that someone is interested in our research! However, I'm afraid that we have only made limited progress since the sticky was posted, due to a hugely underwhelming response from growers who were willing to participate in our survey! We only got one volunteer in the end, which is not enough to run a scientific study. Plus, my workload in the last few months of 2009 was so heavy that I pretty well disappeared off the face of the earth for a while. However, life has now returned to normal and the research is progressing. For reasons outlined above, we're focussing on wild plants now, and it appears that larvae of Aedes albopictus (the No. 1 dengue vector in West Malaysia) have a tough time surviving in Nepenthes pitchers, but it is not impossible for them to do so. We're about to embark on some more experiments over the next few months to try to work out why they don't like Nepenthes pitchers, even though they occur in the same habitats.

An interim conclusion, which is subject to change at any time, is that Nepenthes pitchers are not a significant brood site for Aedes albopictus at the present time. However, we are always interested to hear if any of you have mosquitoes breeding in your pitchers, and if you'd like us to ID them for you, we'd be happy to (as long as you live in Malaysia). We'll keep it anonymous if you prefer, as well.

On a different note, I have several research students commencing new ecological projects on Nepenthes this year and these are all based on wild plants, so we should be able to make faster progress with our research in 2010. At least that's the plan....

Cheers,

Charles

PS. If you have access to the website for the journal "New Phytologist", you can see our latest research article in the "early view" section.

[jixxxs]

Hi Charles,

Thanks for the update on this topic. Its good to know that the Aedes larvae will have a tough time in the pitchers. Will surely keep an eye out if anything is breeding in the pitchers of my plants and let you know if i find anything interesting.

Would it be safe to assume that pitchers with diluted fluid by rain water would be more conducive for Aedes larvae survival as appose to undiluted pitcher fluid?

On a similar note, do you know if sprinkling 'Abate' or other insecticides into the pitchers would affect the plant..?

[Charles]

Thanks - that'd be great!

We don't have a definite answer yet, but my feeling at the moment is that a pitcher whose fluid has been diluted by rainwater would be more likely to provide a suitable habitat for Aedes albopictus (BTW, I'm being specific about A. albopictus as there are some other Aedes species that have actually adapted to living in Nepenthes full-time, but as far as we know they are not disease vectors). This means that if you accidentally add water to pitchers when you are watering your plants, you may end up altering the fluid chemistry in a way that suits A. albopictus. This has obvious implications for N. ampullaria - the contents of its pitchers are always diluted by rainwater in the wild and so this is the species that is of greatest interest to us at the moment.

I don't think there's any need to add chemicals to your pitchers to control larvae - just keep a watch on your entire collection and kill the larvae if you find them (or you send them to us for an ID, but let us know before you do so, so we can advise on how to prepare them for sending). We're also looking at some interesting options for biological control and if these work out, we'll let you know.

Cheers,

Charles

[NepNut]

Charles,
Any new findings for biological control will be very much welcomed to be share among fellow hobbist.

So far the only consistent occupant on many of my pitchers is somekind of small fly that will lay eggs and it's larvae will feed on the remains of the captured prey.

[marvin1997]

Well nothing breed in my neps except dead ants which seems to breed pretty fast....