[SOS-PCA] Washing cotton bags + population question (fwd)
Plant Conservation
plant at plantconservation.org
Fri Sep 17 10:16:56 CDT 2004
---------- Forwarded message ----------
Date: Fri, 17 Sep 2004 14:55:53 -0000
From: Michael Way <M.Way at kew.org>
To: alfmac at u.washington.edu
Cc: sos at kew.org
Subject: [SOS] Re: [SOS-PCA] Washing cotton bags + population question
Carolyn,
We do try to re-use cloth bags whenever possible, but discard any which have
suffered from fleshy fruits or have awned/hooked fruits mistakenly placed
inside-these cannot realistically be recovered.
For the rest, our laboratory assistant gives them a thorough clean with high-
powered vacuum cleaner. I am happy that this removes all the viable seeds
that could otherwise get left in the bags. Cleaned US bags get returned to a
shelf marked for repatriation to US and so far we have sent one large batch
of used bags to texas. Given the small, but real risk of moving pathogenic
microbes around, we did a risk assessment exercise last year as the list of
Oak wilt hosts was extended, but I'd have to check with colleagues if we have
any other measures in place- these would have centered on a standard freezing
step (i.e. at least 2 weeks in our cold room -20 degrees celcius) which is
used by herbaria to kill invertebrate pests and microbes before material is
allowed to enter. We have occasionally autoclaved small bags, but to my
knowledge havn't tried washing with detergent. Carolyn- please let us know
how you get on!
I recall your earlier query about the size of a population: To be an
effective population, individual plants would be in contact spatially (on the
ground) and temporally (similar flowering periods), and not seperated by a
geographical barrier preventing gene flow through pollination, seed or
vegetative propagule dispersal. As we don't have reproductive biology
information for most native species, we have to work from assumptions
-To achieve a population sample, I'd recommend collecting from across the
contiguous occurance of a species in a single geographical unit, randomly and
evenly, up to around 1 mile for insect pollinated species and 10 miles for
wind-pollinated species.
-If there is any sign of partioning/division of the plants in groups in terms
of flowering time, morphology, etc, it is wise to treat these as two
populations.
-If there is no observed divergence of the plants (i.e. they are basically
identical) but they occur in contrasting, but contiguous environments (e.g.
limestone outcrop in the center of an alluvial plain...) then collect evenly
from both environments and combine the sample, making it clear in your
notes. This is called stratified random sampling, and is the gold standard
amongst genetic resource collectors! Your taxon identification must be
perfect in this latter case of course!
I have just checked our frequently asked questions at
http://www.nps.gov/plants/sos/protocol/appendix7.htm and the following entry
may also help:
-------------------------------------------------------------
Q: Can I collect from several locations to get sufficient seed for a single
collection?
A: The sampling strategy is intended to achieve a representative sample of
the genetic diversity of a single population. Seed samples may only be
combined into a single population sample if samples have been collected:
from groups of apparently similar individual plants from nearby locations,
and which appear capable of frequent interbreeding (consider the seed
dispersal characteristics and the kind of pollination agent for the species -
‘nearby’ may mean 1 mile for an insect pollinated species, but as far as 10
miles for a wind-pollinated species) if the sampling approach has been
consistent at each location, such that that combined sample is truly
representative of the population. In this case, it is good practice to note
the location of the centre of each sub-population on the field data form. If
you have any doubt about combining such samples, it would be wise to select
the most suitable sub-population for sampling
------------------------------------------------
Whatever sampling is carried out, its important to indicate on the field data
form how many individuals were sampled across what approximate area of land.
Does this help?
Michael
> ----- Forwarded by Carol Spurrier/WO/BLM/DOI on 09/16/2004 09:57 AM -----
>
> "Carolyn
Alfano"
> <alfmac at u.washington.edu> To:
<sos at lists.plantconservation.org>
> Sent by:
cc:
> SOS-bounces at lists.plantconse Subject: [SOS-
PCA] Washing cotton bags
>
rvation.org
>
>
> 09/15/2004 07:06
PM
>
>
>
>
>
>
> Is it OK to wash the cotton bags using regular detergent and reuse them?
> Has anyone tried this? Do they shrink?
>
>
> Thanks,
>
>
> Carolyn
>
>
> Washington Rare Plant Care and Conservation
>
>
> Center for Urban Horticulture
>
>
> University of Washington
>
>
> Box 354115 Seattle, WA 98195-4115
>
>
> ----------------------------------
>
>
> Ph: 206-616-0780
>
>
> Fax: 206-685-2692
>
>
> depts.washington.edu/rarecare
> _______________________________________________
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>
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n.org
>
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>
>
>
>
--
Michael Way
Americas Co-ordinator
RBG Kew Millennium Seed Bank Project
tel +44 (0) 1444-894106
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