Quite a difficult job...if you do not solve the problem, Monofloral strawberry honey should be used for determining of nectar's properties.

Hello Peter,

I have no direct experience on strawberry flowers so maybe this would not be possible, but how about trying with a micropipette (0.5-10 microlitres)? You could extract it and put it in a microtube, then use microcapillary tubes to quantify its volume (ore some other techniques). I know it is not the most linear procedure but it might work.

Why do you think microcapillary tubes did not work?

Alessandro

This case is related in technical. But I am working about agricultural economics.

Hi Peter,

have you already tried the 1µl microcapillaries? We have obtained good data with those even from very tiny flowers with very low amounts of nectar. We also had good results in measuring sugar percentage afterwars using a common refractometer by diluting the nectar with destilled water of a defined quantity. For details see Ackermann & Weigend 2006 (http://aob.oxfordjournals.org/content/98/3/503.short).

The capillaries are those: http://mediando.wepa-apothekenbedarf.de/index.php?IdTreeGroup=1287&IdProduct=8154

They are even available in 0.5µl.

Regards

Tilo

Peter,

If the flowers have a considerable amount of nectar, try to attach the flower to a cap of a centrifuge tube by means of a needle, close the tube with the cap and centrifuge it at an appropriate speed. You may be able to collect some nectar. If available read : Kearns, C.A., Inouye, D.W., 1993. Techniques for pollination biologists. University Press of Colorado.

Best of luck

If the very small (0.1 or 0.2 ul) microcaps don't work, perhaps one option would be to draw out a microcap (maybe a 5ul microcap) in a flame so you end up with two fine microcaps with a hairlike taper, then break one off to give a very fine tip, and use this to draw up some nectar. If you need to measure the volume you can either discharge the drop into a small microcap (under a dissecting microscope, so that you can see what you are doing) or discharge the drop into a pool of liquid paraffin and measure the diameter of the spherical drop.

Sally

There are various tricks that may help.

One is to keep the flowers in a plastic covering (bag) with a soaked ball of cotton wool. The added humidity may ease the extraction of greater volume, and lower viscosity, of accumulated nectar.

The trick of using small microcaps that have been drawn out, as Dr. Corbet suggests should also be tried. Once you have nectar in the microcap, you can measure sugar concentration. By placing nectar (not necessarily the same sample) on filter paper, the size (diameter) of the spot can be converted to a volume. Dr. Corbet's technique is interesting and may be more accurate. I have not tried it. Rinsing and washing do work, but you must know how much distilled water you are placing in the flower, and then make the simple arithmetical conversions to **estimate** sugar concentrations, The book Practical Pollination Biology (Ed. by A. Dafni et al. has comprehensive methods on how to extract nectar from flowers, as does the Kearns & Inouye book noted by Thinila. The book Practical Pollination Biology is easily available through the printers www.volumesdirect.com, or through Bioquip in California, or in Europe through Natural History Books in UK.

Peter

See the following Plants are Cool, too video:

https://www.youtube.com/watch?v=8IPQTs0cfqw

Hi I have not done this myself but a colleague of mine used the following method http://ac.els-cdn.com/S1439179110000174/1-s2.0-S1439179110000174-main.pdf?_tid=6c67750a-e5f0-11e3-b566-00000aacb360&acdnat=1401230832_2b8bd93dec0a33e396e42ae91e99019b

to collect nectar from multiple plant species, some of which were also opened small flowers. Maybe worth a go?

G'day Peter,

We've been exploring this with flowers producing low nectar volumes in Western Australian native flora. This paper was particularly helpful in providing an array of techniques:

D. S. Morrant, R. Schumann and S. Petit 2008 Field methods for sampling and storing nectar from flowers with low nectar volumes Annals of Botany 103: 533–542, 2009.

The washing techniques seem to work for us, but the resulting nectar is dilute. We've needed to explore HPLC and freeze concentration to get sugars, lipids and amino acids. I'd be interested to know how you go, since a domestic cultivar should be far less challenging than ecollgically-constrained wild plants.. Hope this helps

I haven't tried this technique yet, but may experiment with it this summer. I'd like to find out whether weighing a butterfly or bee, then allowing it to feed from a flower(s), and then re-weighing it would allow me to measure the volume of nectar collected. If the bee in question is large enough (e.g., honey bee or larger) it might be possible to extract the nectar from the bee in order to measure concentration, etc.

Yes, it’s possible. I observed a stingless bee species harvest a fluid in lesions produced by it in the stem of a medicinal plant. Then I pressed the abdome of the bee between my finger and I immediately harvested the regurgitated sap using a microsyringe (5μl). After that the sugar concentration was verified using a common refractometer.

Now I return to first question, here in Brazil I have harvested strawberry nectar using microserynges (5μl e 10 μl). However my data show that here the strawberry cultivars produce more nectar than in other countries.

Thanks all for your help, it was very appreciated. We ended up using 0.5µl microcapillaries which worked well, it seems the diameter of the larger capillaries was just too big to reach the nectaries.

Thanks again all.