Date: Wed, 18 Sep 1996 09:38:31 +0300
From: "Costas A. THANOS" (cthanos@atlas.uoa.gr)
To: SEED-BIOLOGY-L@cornell.edu
Subject: Thermogradient Germinator
Dear Friends,
Our team has recently got a fair amount of money (around 18000 US$ or 12000 Bpounds) and we have decided to buy a thermogradient germinator. Our goal is to check for seed germination (mostly in lots of wild-grown plants) in a massive experiment that should include various constant and diurnally alternating temperatures (the latter means one day temperature and one night one - plus the ability to set the day/night durations as desired). We are aware of the Grant brand (UK) instrument but this seems to exceed our resources.
Thus, I would be grateful for any information on the availability in the market of such an equipment and I would appreciate any relevant details (address, fax numbers, WWW sites, tel. etc).
Regards and thanks
Costas A. Thanos
Univ. Athens, Greece
email: cthanos@atlas.uoa.gr
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Date: Thu, 19 Sep 1996 11:05:35 +1000
From: Phillip.Davidson@mailbox.uq.oz.au (Phillip Davidson)
To: SEED-BIOLOGY-L@cornell.edu
Subject: Thermogradient Germinator
Dear all,
There is a company that makes thermogradient tables in Brisbane-Australia, usually to custom orders and\or requirements. A price check with the company today gave a figure of approximately $12,600-00 Aust., but as mentioned, you can have specific requirements built in. I believe they base their design on Arnold Larson's 1971 paper:
Two-way thermogradient plate for seed germination research: Construction plans and procedures, USDA, Agriculture Research Service p51-41.
There have been at least 6 built and in use in Australia by various researchers\departments. The company contact details are:
Linder & May Pty Ltd
Refrigeration Engineers
243 Lutwyche Rd
Windsor, Brisbane, 4030
Tel: (07) 3365 1141
Fax: (07) 3857 1142
As a brief word of advice, make sure you order the equipment 6 months to a year prior to needs as they take a while to churn out equipment depending on their work loads in other areas at the time. They also custom make a range of incubators\germination cabinets of varying sizes $2000 to $4000-00 in price range. (we have about 6 of their large germination cabinets). They also make other custom equipment.
Contact people there are: Bob Linder, Phil May or usually Graeme Shumann. Please feel free to contact me if you require further information.
Regards,
Phil Davidson
Research Scholar
University of Queensland, Australia
Email: Phillip.Davidson@mailbox.uq.edu.au
Tel: (07) 3365 4814
Fax: (07) 3365 1177
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Date: Thu, 19 Sep 1996 11:20:43 +0200
From: dfscdk@post4.tele.dk (Joergensen, Melita Froelich (Danida Forest Seed Centre))
To: SEED-BIOLOGY-L@cornell.edu
Subject: Thermogradient Germinator
Dear Costas A Thanos
If your team is interested in building your own thermogradient germinators you should contact: Martin Jensen, Research Centre Aarslev, Kirstinebjergvej 10, 5792 Aarslev, Denmark (Fax:+ 45 65 99 25 66). He had two made a few years back and would be happy to share his experiences with you.
Regards
Kirsten Thomsen
Danida Forest Seed Centre
Denmark
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Date: Thu, 19 Sep 1996 09:15:00 -0400
From: welbaum@mail.vt.edu (Greg Welbaum)
To: SEED-BIOLOGY-L@cornell.edu
Subject: Thermogradient Germinator
Dear Costas,
Seedburo and other seed supply companies sell thermogradient tables already
made but they are very expensive < US$6,500. With the help of our
engineering department, I made my own for about $300 (not counting labor or
the cost of the circulating baths) a few years back. We are very pleased
with the unit we built. It works very well. We acquired an aluminum sheet
that was 6 mm thick and the dimensions were 1.2 meter by 0.7 meter. We
welded a square pipe onto the bottom of the aluminum so the pipe was in
close contact with the aluminum. The flat pipe was configured in a tight
"U" shape at opposite ends of the aluminum sheet so it would rapidly
circulate the coolant from the bath. The pipe and aluminum plate were
mounted in a styrofoam-lined, wooded enclosure with a removable lid. The
gaps were injected with polyureathane insulation. The diameter of the pipe
used was approximately 2.5 cm. So maybe you can build your own?
Good luck,
Gregory E. Welbaum, Ph. D.
Associate Professor
Department of Horticulture
306-B Saunders Hall
Virginia Tech
Blacksburg, VA 24061-0327 USA
phone (540)231-5801
fax (540)231-3083
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Date: Thu, 19 Sep 1996 17:01:54 bst
From: "A J Murdoch, Reading University" (A.J.Murdoch@reading.ac.uk)
To: SEED-BIOLOGY-L@cornell.edu
Subject: Temperature gradient plate germinators
Incidentally on a question of semantics, it seems to me that the equipment generates temperature gradients rather than thermo (heat) gradients: with good insulation there should actually be a constant flow of heat along the temperature gradient.
We also at Reading have constructed our own bidirectional plates. The downside of the do-it-yourself approach is that it can take a long time and a good engineering workshop is essential to build a two-way plate. The one way version described by Greg Welbaum is of course much simpler. For many species (especially those with larger seeds which often do not respond to temperature fluctuations) the one way version may be all that is needed (depending on the objectives of the investigation)
PS When someone asked us to build a two-way plate for them, we thought about it for a while and then decided to license our design to Grant Instruments (Cambridge, UK) so we do have some interest in sales of the commercial product!!
Alistair Murdoch.
Dr A.J. Murdoch, Department of Agriculture, The University
Earley Gate, PO Box 236, READING RG6 6AT, U.K.
TEL.: +44 (0)118 931 6746. FAX: +44 (0)118 931 8297
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Date: Thu, 19 Sep 1996 12:42:43 -0400 (EDT)
From: rdkeys@unity.ncsu.edu
To: SEED-BIOLOGY-L@cornell.edu
Subject: Thermogradient plates --- 1-way vs. 2-way --- pros and cons etc.
Greetings to the list. Although I have not posted anything here, before, I have been reading the list almost since it began. It is, refreshing, although perhaps some more traffic and general discussion would be of merit, as folks may have time.
I would be interested in some discussion of thermogradient plates for germination work. That topic has passed by in today's email, and it seems that there are others using them for various types of studies.
Let me play the devil's advocate, of sorts, and take the point of view of ``Why in the world would anyone want a 2-way thermogradient plate over a 1-way thermogradient plate?'' I would be most curious to hear other investigators pros and cons of either style plate. Also, what sorts of problems have you run into, using either style of plate? This is the kind of thing that does not usually wind up in the published materials and methods or results and discussion. It is also not the kind of thing that manufacturers are likely to discuss.
I tend to prefer the 1-way plate, for its simplicity. But, others may have their reasons for using the 2-way plate, instead.
What bed thickness and surface dimensions work well, or better than others? I prefer a minimum thickness of 25 mm, for good heat conduction. Also the cooling blocks on the edges are 100 mm square in cross-section with large water channels to provide good thermal mass stability. I have not seen many commercially available models of such robust construction. Maybe it is not really needed, although I would hedge my bet for the greater plate mass where possible.
What, if any, condensation problems occur on the colder sections of the plate? I get some at the coldest 10cm of the plate, and have been thinking about milling some drainage grooves in that section of the plate to form condensation drains.
What sorts of germination systems work best? I use Petri dishes or Erlenmeyer flasks, and they work relatively well, although internal condensation problems on the upper lid of petri dishes makes watering of the higher temperature treatments more frequent than lower temperature treatments. Small plastic boxes work relatively well, but also can suffer from watering problems in the higher temperature treatments. If I were to design a lid, it should be somewhat peaked with an inside ridge so that it would drain back to the edge with the force of gravity once condensation droplets reached a certain size.
So, your thoughts are appreciated, on any matters relating to the use of thermogradient germination plates, for our purposes of scholarly discussion.
Best Regards
Bob Keys
rdkeys@unity.ncsu.edu
Robert D. Keys, Assoc. Prof. Seed Research
Department of Crop Science
4411 Williams Hall
North Carolina State University
Raleigh, NC 27695-7620, USA
Tel: (919) 515-5071
************************************************
Date: Fri, 20 Sep 1996 12:07:12 bst
From: "A J Murdoch, Reading University" (A.J.Murdoch@reading.ac.uk)
To: SEED-BIOLOGY-L@cornell.edu
Subject: Thermogradient plates --- 1-way vs. 2-way --- pros and cons etc.
Bob Keys wrote,
>> ``Why in the world would anyone want a 2-way thermogradient plate
>>over a 1-way thermogradient plate?''
(1)The simple answer is ecological: constant temperatures rarely occur in the real world and in most ecosystems diurnal temperature fluctuations occur at those depths in the soil profile from which successful emergence occurs. The criticism of two-way plates is that the temperature follows a square wave and not the smooth curve found in soil. The answer to that is that you have to start somewhere and the alternating temperatures are used as an approximation. Ultimately the approximation must be validated: does anyone know if this has been tested?
(2) The next answer is technological: alternating temperatures help to relieve the dormancy of many small-seeded species and hence alternating temperatures are useful to seed testers. A two-way plate is then incredibly useful as it enables seed testes to optimise the temperature regime for viability testing of species whose germination characteristics are not known.
(3) The third reason is scientific: the use of a two-way plate enables one to model germination responses to alternating temperatures (see Murdoch et al. Ann.Bot. 63: 97, 1989). Such models may be of predictive or comparative value for ecologists, or technologists . The models which can be constructed may also (possibly!) enable one to have an insight into mechanisms of dormancy though some would dispute that.
>>I tend to prefer the 1-way plate, for its simplicity. But, others
>>may have their reasons for using the 2-way plate, instead.
We use our two way plate in a single direction sometimes. The one-way plate is all that is needed for many species and is ideal for developing thermal time relationships for the rate of germination.
>>What bed thickness and surface dimensions work well, or better than
>>others?
I prefer a minimum thickness of 25 mm, for good heat conduction.
I don't think it's needed provided insulation above and below the plate is good
>>Also the cooling blocks on the edges are 100 mm square in cross-section
>>with large water channels to provide good thermal mass stability.
I think this would cause problems with a two-way plate though not with a one way plate
>>I have not seen many commercially available models of such robust
>>construction. Maybe it is not really needed, although I would hedge
>>my bet for the greater plate mass where possible.
In practice and in theory (if you work out heat transfers etc.) it's not needed
>>What, if any, condensation problems occur on the colder sections of the
>>plate?
Considerable condensation is bound to occur which may be a problem if you want to work at different water potentials. The most important thing though is to prevent drips dropping on to the seeds so we either germinate between paper or line lids with absorbent paper.
>>What sorts of germination systems work best? I use Petri dishes or
>>Erlenmeyer flasks, and they work relatively well, although internal
>>condensation problems on the upper lid of petri dishes makes watering
>>of the higher temperature treatments more frequent than lower temperature
>>treatments. Small plastic boxes work relatively well, but also can suffer
>>from watering problems in the higher temperature treatments. If I were
>>to design a lid, it should be somewhat peaked with an inside ridge so that
>>it would drain back to the edge with the force of gravity once condensation
>>droplets reached a certain size.
We use small plastic boxes or petri dishes when applying chemicals or controlling water potential. For some applications we line the base of the plate with chromatography paper and overlap into water troughs at the edges. No water need then be applied directly to the plate.
Have fun!
Dr Alistair J. Murdoch, Department of Agriculture, The University
Earley Gate, PO Box 236, READING RG6 6AT, U.K.
TEL.: +44 (0)118 931 6746. FAX: +44 (0)118 931 8297
*******************************************
Date: Mon, 23 Sep 1996 11:31:12 -0400 (EDT)
From: rdkeys@unity.ncsu.edu
To: SEED-BIOLOGY-L@cornell.edu
Subject: Re: Thermogradient plates --- 1-way vs. 2-way --- pros and cons etc.
Excellent discussion, Prof. Murdoch. This is the kind of thing that I think will provide a furtherance of the ``state-of-the-art''.
>>Bob Keys wrote,
>>>> ``Why in the world would anyone want a 2-way thermogradient plate
>>>>over a 1-way thermogradient plate?''
>>(1)The simple answer is ecological: constant temperatures rarely occur in
>>the real world and in most ecosystems diurnal temperature fluctuations
>>occur at those depths in the soil profile from which successful emergence
>>occurs. The criticism of two-way plates is that the temperature follows a
>>follows a square wave and not the smooth curve found in soil. The answer
>>to that is that you have to start somewhere and the alternating
>>temperatures are used as an approximation. Ultimately the approximation
>>must be validated: does anyone know if this has been tested?
Now we are at the meat of the matter. I would agree that a square wave function is not the best approximation of the general sine wave-``like'' diurnal fluctuation that naturally occurs in the field. I am not aware of any particular validation of the equality of these two functions, as to seed germination. I suspect someone should run that through their temperature gradient plate, pending some spare funding for proportional temperature controllers that would be programmable for the various desired approximations to sine wave functions. I am not an engineer, but there should be some way to, for example, mix warm and cold waters proportionally to allow a smooth sine wave diurnal temperature gradient to be set up. The problem then becomes, ``what is the range of diurnal temperatures to use.'' Back in 1981, when I was trying to measure field temperature gradients for peanut seed germination work, the diurnal fluctuations might be some +-5C for cool early season germination and perhaps some +-10C for later season germination when soils had warmed. Thus, the range expected on a diurnal cycle on the temperature gradient plate should be different in amplitude for the cold and warm sections of the plate. Also, such things as cloud cover and rain in the field will significantly alter the diurnal temperature pattern, and would need to to be incorporated in such temperature gradient plate design, and modeled into data obtained from same.
>>(2) The next answer is technological: alternating temperatures help to
>>relieve the dormancy of many small-seeded species and hence alternating
>>temperatures are useful to seed testers. A two-way plate is then
>>incredibly useful as it enables seed testers to optimize the temperature
>>regime for viability testing of species whose germination characteristics
>>are not known.
Agreed.
>>(3) The third reason is scientific: the use of a two-way plate enables one
>>to model germination responses to alternating temperatures (see Murdoch et
>>al. Ann.Bot. 63: 97, 1989). Such models may be of predictive or
>>comparative value for ecologists, or technologists.. The models which
>>can be constructed may also (possibly!) enable one to have an insight
>>into mechanisms of dormancy though some would dispute that.
Agreed. I would think that in cases of a dormancy such as thermodormancy in, for example, lettuce seed and possibly things like Amaranthus spp. which seem to have what I would consider a thermodormancy, this type of predictive or comparative modeling would be of value. Likewise, very precise control of the temperature gradient plate, diurnally, would be desirable.
>>>>I tend to prefer the 1-way plate, for its simplicity. But, others
>>>>may have their reasons for using the 2-way plate, instead.
>>We use our two way plate in a single direction sometimes. The one-way
>>plate is all that is needed for many species and is ideal for developing
>>thermal time relationships for the rate of germination.
Agreed. Perhaps, what I was getting at was that there is a good case for having both types of temperature gradient plate around, if space, funding, and materials permit.
>>>>What bed thickness and surface dimensions work well, or better than
>>>>others? I prefer a minimum thickness of 25 mm, for good heat conduction.
>>I don't think it's needed provided insulation above and below the plate is
>>good.
I insulate my plate (a 1-way) with 60mm of thermal insulating foam (R12 value) on the bottom, and that works in my installation. The large thermal mass that I use helps to maintain stability. On a 2-way plate, I would expect that might be useful to even out the temperature changes over time, especially for a stepwise change per unit time. One of the things I need to do yet is measure the thermal drift of my plate over a diurnal period in the lab. The spot checking I have done of the plate indicates it to be stable to +-0.1C, and linear across its surface under all conditions that I have checked, to date. One of my fears in using insufficient thermal mass in a plate is non-linearity in the gradient and odd temperature fluctuations due to uncontrollable external factors.
>>>>Also the cooling blocks on the edges are 100 mm square in cross-section
>>>>with large water channels to provide good thermal mass stability.
>>I think this would cause problems with a two-way plate though not with a
>>one way plate.
Agreed on the 1-way plate, but, even with the 2-way plate, I would expect that a larger thermal mass would be preferable to a lesser thermal mass, if for no other reason, to smooth out changes of temperature. If one wanted a diurnal cyclic pattern, then the smoothness due to a large thermal mass would be advantageous. On a large step or square wave pattern, where one wanted a relatively instantaneous change, then the mass might be a problem. I would play the devil's advocate and opt for the larger mass.
>>>>I have not seen many commercially available models of such robust
>>>>construction. Maybe it is not really needed, although I would hedge
>>>>my bet for the greater plate mass where possible.
>>In practice and in theory (if you work out heat transfers etc.) it's not
>>needed.
Its use would be as the flywheel effect in electronics circuits or rotary motion, and thus might be of some use.
>>>>What, if any, condensation problems occur on the colder sections of the
>>>>plate?
>>Considerable condensation is bound to occur which may be a problem if
>>you want to work at different water potentials. The most important thing
>>though is to prevent drips dropping on to the seeds so we either germinate
>>between paper or line lids with absorbent paper.
In this case, I was thinking more of condensation on the plate surface, although the point of condensation within the germination system is also a good point. How is it that you line the lids with absorbent paper, i.e., how is the paper stuck to the bottom surface of the lids. The choice of binder or glue could be important, in that any residues therefrom might influence the subsequent germinations, or would have to be thoroughly washed in some way to remove said residues.
>>>>What sorts of germination systems work best? I use Petri dishes or
>>>>Erlenmeyer flasks, and they work relatively well, although internal
>>>>condensation problems on the upper lid of petri dishes makes watering
>>>>of the higher temperature treatments more frequent than lower temperature
>>>>treatments. Small plastic boxes work relatively well, but also can
>>>>suffer from watering problems in the higher temperature treatments.
>>>>If I were to design a lid, it should be somewhat peaked with an inside
>>>>ridge so that it would drain back to the edge with the force of gravity
>>>>once condensation droplets reached a certain size.
>>We use small plastic boxes or petri dishes when applying chemicals or
>>controlling water potential. For some applications we line the base of
>>the plate with chromatography paper and overlap into water troughs at the
>>edges. No water need then be applied directly to the plate.
Interesting wick action for watering. I will have to try that. For closed system, like small boxes, etc., I was thinking perhaps of something along the line of some sort of bacteriological growth container or cell flask that might not have the internal condensation problems. To date, I have not found anything satisfactory. The best system that I have found, to date, is a simple Erlenmeyer flask, stoppered, which is also good for administration of gases such as ethylene and carbon dioxide.
>>Have fun!
Oh, indeed! The list makes a very good way of exchanging ideas and pondering points of view, even better than the back rooms and corners of meeting halls or poster sessions, or even the pub....., well, almost.
>>Dr Alistair J. Murdoch, Department of Agriculture, The University
>> Earley Gate, PO Box 236, READING RG6 6AT, U.K.
>>TEL.: +44 (0)118 931 6746. FAX: +44 (0)118 931 8297
Dr. Robert D. Keys, Department of Crop Science, Box 7620, North Carolina State
University, Raleigh, NC 27695-7620, USA. (919)-515-4071.
rdkeys@unity.ncsu.edu (university)
rdkeys@csemail.cropsci.ncsu.edu (office)
rdkeys@seedlab2.cropsci.ncsu.edu (lab).
p.s. Might I request of all the list participants that we try to keep our emailings to 72 columns or less, since the listowner adds one column and any reply adds 3 columns
*******************************************
Date: Mon, 23 Sep 1996 12:31:37 -0400 (EDT)
From: rdkeys@unity.ncsu.edu
To: SEED-BIOLOGY-L@cornell.edu
Subject: Please 72 column mail width
A previous posting got nuked by our localized internet instabilities.....
For general consideration (pending the list owners agreement):
Might I request of all the list participants that we try to keep our emailings to 72 columns or less, since the listowner adds one column and any reply adds 3 columns. Thus, to prevent inadvertent and hard-to-read line-wrapping, can we all try to keep our line lengths in check. Standard internet ascii mail should be 80 columns or less. Workstations and windows driven machines may exceed this, unknowingly. It has to do with non-standard fonts and font sizes being translated to the standard format 80 column lines. When you invoke your mailer you may not realize that this is happening, because it usually does not show on your screen.
Examples:
This line will wrap and be difficult to read due to its being over 78 columns inlength. A following line will tend to also be difficult to read if it is longer than expected. Thus, lengthy lines can lead to lengthy head scratchings, ponderings and other sorts of nuances that make reading email difficult, at best.
This line will not wrap and even with the added front > or > >and is fine.
The following ruler line is 72 characters long, for reference.
1 2 3 4 5 6 7
123456789012345678901234567890123456789012345678901234567890123456789012
************************************************************************
Thanks for your patience and consideration --- now back to seeds!
Dr. Robert D. Keys, Department of Crop Science, Box 7620, North Carolina
State University, Raleigh, NC 27695-7620, USA. (919)-515-4071.
rdkeys@unity.ncsu.edu (university)
rdkeys@csemail.cropsci.ncsu.edu (office)
rdkeys@seedlab2.cropsci.ncsu.edu (lab).
******************************************************
Date: Mon, 23 Sep 1996 19:41:00 -0700 (PDT)
From: "Pallais, Noel" (N.PALLAIS@CGNET.COM)
To: SEED-BIOLOGY-L@cornell.edu
Subject: Definition of thermodormancy: A question
In the preceding discussion about thermogradients for germination, the comment below (>>>>>) was made, which reflects a definition of thermodormancy that I have found often in the literature but that I don't agree with. And, I would like to request opinions so I can either change my way of thinking or persist with my understanding of the term "thermodormancy".
I am probably mistaken but in my mind seeds are "thermodormant" when they have acquired dormancy due to exposure to nonlethal but extreme temperature conditions. While seeds should be termed "thermo-inhibited" when exposed to temperatures which exceed their range of possible germination.
The distinction is a bit more than a linguistic matter to us since we work with true potato seeds, which are dormant (germination is impeded or slow, widespread and erratic) at harvest because the range of allowable germination temperatures is relatively narrow 15 C ( 2), while as storage proceeds and dormancy is gradually lost, the upper allowable temperature for germination increases up to 29 C ( 2); the lower temperature limit may or may not slightly decrease a few of degrees depending on the genotype.
I like to describe true potato seeds as "dormant" when they don't germinate or have difficulty germinating under a temperature condition that otherwise would be favorable, and "nondormant" when they germinate rapidly and uniformly at 27 C. We have published evidence indicating thermodormancy ( i.e. nondormant seeds became dormant when stored at high temperature and moisture) may be induced in true potato seeds, and that true potato seed germination is thermo-inhibited at temperatures above 30 C.
HELP!
>>>>>>Agreed. I would think that in cases of a dormancy such
>>>>>>as thermodormancy in, for example, lettuce seed and
>>>>>>possibly things like Amaranthus spp. which seem to
>>>>>>have what I would consider a thermodormancy, this
>>>>>>type of predictive or comparative modeling would be
>>>>>>of value.
Noel Pallais
International Potato Center
Peru
n.pallais@cgnet.com
************************************
Date: Wed, 25 Sep 1996 08:40:51 bst
From: Prof Richard Ellis (R.H.Ellis@reading.ac.uk)
To: SEED-BIOLOGY-L@cornell.edu
Subject: Thermodormancy and conditional dormancy
Thermodormancy
Although the above is widely used in lettuce for example where germination of viable seeds no longer occurs at cool temperatures following exposure to warm temperatures, another term used where germination after harvest (etc) is limited to a very narrow range of temperatures to cover inability to germinate at cooler or warmer temperatures (i.e. different to thermodormancy) is conditional dormancy.
Richard
Professor Richard Ellis,
Department of Agriculture, The University of Reading,
Earley Gate, P.O. Box 236, Reading RG6 6AT, UK
Phone +44 (0)118 931 8488 Fax +44 (0)118 931 8297
e-mail: R.H.Ellis@reading.ac.uk
************************************
Date: 25 Sep 96 15:33:17 EDT
From: Arjan Stolte (100723.1150@CompuServe.COM)
To: SEED-BIOLOGY-L@cornell.edu
Subject: thermogradient plates
Dear Mr. Thanos,
Our company, Bejo Zaden bv, and more companies and universities, have best
experiences with the thermogradient tables made by:
Van den Berg Klimaattechniek
Achthoven West 21
3417 BW Montfoort
the Netherlands
tel +348 473 322
fax +348 474 561
They make very good equipment for good prices. Also two way thermogradients are possible, as are different night and day settings. The temperatures are extremely stable.
We use to do our germination tests on round filterpaper, placed on top of a wet layer of a water holding system, like a large sheet of blotter paper (or cloth, or whatever). To keep humidity and temperature, the round filterpapers are covered with the well-known bell shaped lits, used on Copenhagen tables. This all is covered with perspex lits like halfopen boxes, covering 6*3 samples, while our tables can hold 18*9 samples each (diameter filter paper = 10 cm). Good quality filter paper can be purchased for instance with Schut Papier, Heelsum, the Netherlands.
Success and regards,
Arjan Stolte
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