HDTenEightyP/NetNews huggingface dataset:
From: MEK104@psuvm.psu.edu
Newsgroups: bionet.plants
Subject: Re:H2O/CO2 diffusion rates
Date: 11 Nov 92 17:34:44 GMT
Organization: Penn State University

bwilliam@oyster.smcm.edu (Bill Williams) in article <16925@umd5.umd.edu>
writes:

>In article <92311.111507MEK104@psuvm.psu.edu> , MEK104@psuvm.psu.edu
writes:

>>I tend to agree in that I'm skeptical, but I think an important factor
>>that may not be included in some of the theoretical and experimental work
>>is the heat exchange that occurrs from leaf to atmosphere.  To take the
>>debate full circle, could the relative size of individual stomata have an
>>effect on heat exchange?  This could also be way out of whack since I'm
>>not familiar enough with the literature.

>Since the relevance of stomata to heat exchange is entirely through
>transpiration, I don't see how this could be the case unless data for
>transpiration were estimated from direct microscopic measurements of
>stomatal aperture, distribution, pore length, and so on.  As far as I know,

Good point, I suppose thats the basis of this discussion: Does stomatal size
(ie guard cell length) as it relates to sun versus shade leaves have an
influence on transpiration rate and/or water use efficiency?  I was simply
raising the question, "do models of molecular diffusion across porous
membranes, meant to simulate CO2/H2O exchange through leaf epidermis,
consider the temperature differential between air and leaf"?  If not, a
major aspect of leaf gas exchange is ignored.

>no one has successfully modeled the biophysics of transpiration at that
>level.  There is someone in Germany (name forgotten) who has recently set
>up a gas-exchange apparatus with a transparent cuvette and a long-distance
>microscope, so the dimensions of the pores and the gross leaf conductance
>can be compared.  I haven't seen any results yet, but they should be
>exciting.

This definately sounds exciting.  If you recall who is doing this, I'd sure
appreciate the info.


Mark Kubiske                < MEK104@PSUVM.PSU.EDU >
School of Forest Resources
Penn State University
Xref: sparky bionet.plants:593 rec.gardens:7931 soc.culture.british:15715
From: mckeonj@ul.ie
Newsgroups: bionet.plants,rec.gardens,soc.culture.british
Subject: Re: Domestication of poison ivy
Date: 2 Nov 92 09:34:04 GMT
Organization: University of Limerick, Ireland

In article <1992Oct26.141307.22992@NeoSoft.com>, claird@NeoSoft.com (Cameron Laird) writes:
> In article <1992Oct26.052850.1073@ncsu.edu> samodena@csemail.cropsci.ncsu.edu (S. A. Modena) writes:
>>In article <1992Oct24.151527.2352@athena.cs.uga.edu> karen@athena.cs.uga.edu (Karen Snetselaar) writes:
>>>>
>>>...................  Written for the "general public in non-technical 
>>>style" it has chapters on the history of poison ivy (has been a desireable
>>>ornamental in some European gardens for example), .............
>>
> Hurry, please, someone more knowledgeable, and straighten
> us out on this one.  The story I'd always heard was that
> The English Are Different From Us, and take their gardening
> VERY seriously, and some of them are so wild for special
> effects that they're willing, and even eager, to trade
> poison ivy's admittedly distinctive fall foliage for its
> hostility to human ways.  They like the color of the leaves,
> and, to a lesser extent, its varied habits.
A parallel case exists here, on the Plassey Estate, now the University
Campus. A former owner of the estate, William Russell, was a keen
gardener and plant collector. Amongst other exotica, he transplanted
the "giant hogweed" from America (South, I think) for decorative
effect. This has thrived, and now dominates the lower Shannon river
banks. It is extremely noxious, a brush against the foliage with
bare skin in high summer could put you in hospital or worse.
It is a large umbelliferous plant up to 8 feet tall and of alien
appearance, very inviting for being attacked with sticks by boys
of all ages. The sap has a synergic effect with UV light, raising
painful weals on the skin, and apparently in some cases interfering
with cardiac functions.
Two other owners of the estate bear mentioning: Shaw, who was 
exporting grain to the USA during the Irish Famine, and the founder,
Baron Clive of Plassey, better known as Clive of India, a rapacious
agent of the British East India Company, founder of the British Raj.
-- 
"If England sleeps, shall Ireland dream?" : Se/an macEoin
-------------------------------------------------------------------
John McKeon, Material Science Dept. University of Limerick, Ireland
From: MEK104@psuvm.psu.edu
Newsgroups: bionet.plants
Subject: Re: super-optimal stomatal conductance
Date: 11 Nov 92 17:54:05 GMT
Organization: Penn State University

HELP!!!

It seems that I read somewhere, some time ago that certain species will have
stomatal conductance rates much higher than what is needed to maintain
maximal photosynthetic rate given other environmental constraints (eg
light).  In other words, water use efficiency is not maximised.  Does anyone
know off hand of a reference for this which may speculate as to the
ecological significance?

I'd appreciate any help, either over the net or by e-mail.

Thanks

Mark Kubiske                < MEK104@PSUVM.PSU.EDU >
School of Forest Resources
Penn State University
From: ajt@rri.sari.ac.uk (Tony Travis)
Newsgroups: bionet.plants
Subject: Re: H2O/CO2 diffusion rates
Date: 11 Nov 92 18:06:09 GMT
Reply-To: ajt@rri.sari.ac.uk
Distribution: bionet
Organization: Rowett Research Institute
Original-To: plantbio@uk.ac.daresbury

In article <921111143820.MIN-LTFAa15611.bionet-news@uk.ac.daresbury> you wrote:
: In article <92311.111507MEK104@psuvm.psu.edu> , MEK104@psuvm.psu.edu
: writes:
: >I tend to agree in that I'm skeptical, but I think an important
: factor that
: >may not be included in some of the theoretical and experimental work
: is the
: >heat exchange that occurrs from leaf to atmosphere.  To take the
: debate full
: >circle, could the relative size of individual stomata have an effect
: on heat
: >exchange?  This could also be way out of whack since I'm not familiar
: enough
: >with the literature.
: 
: Since the relevance of stomata to heat exchange is entirely through
: transpiration, I don't see how this could be the case unless data for
: transpiration were estimated from direct microscopic measurements of
: stomatal aperture, distribution, pore length, and so on.  As far as I
: know, no one has successfully modeled the biophysics of transpiration
: at that level.  There is someone in Germany (name forgotten) who has

Not Rainer Loesch at Wurtzburg is it?  He did some brilliant work in the
'70s about transpiration.  I've lost track of his current work though.

: recently set up a gas-exchange apparatus with a transparent cuvette and
: a long-distance microscope, so the dimensions of the pores and the
: gross leaf conductance can be compared.  I haven't seen any results
: yet, but they should be exciting.

Hans Meidner (a famous stomatal physiologist) once told me that he had
made an instrument like an engineers needle micrometer that was
sensitive enough to be placed directly in a stomatal aperture and
measure stomatal movements directly!

This was at an SEB conference in Sterling (Scotland) a long time ago,
and we were just chatting about measuring stomata in the dark (I was
using a viscous flow porometer at that time).  I believe he did make
such an instrument (he was a watchmaker's apprentice as a boy) but I
never saw it in use ...

	Tony.
--
Dr. A.J.Travis,                       |  Tony Travis
Rowett Research Institute,            |  JANET: <ajt@uk.ac.sari.rri>
Greenburn Road, Bucksburn,            |  other: <ajt@rri.sari.ac.uk>
Aberdeen, AB2 9SB. UK.                |  phone: 0224-712751
From: david90@milton.u.washington.edu (Ernesto Alvarado)
Newsgroups: bionet.plants
Subject: Re: How high do Century Plants (maguey) get?!?
Date: 6 Nov 92 01:16:49 GMT
Organization: University of Washington, Seattle

In article <dz_qvxh@lynx.unm.edu> rsquires@cyclops.eece.unm.edu (Roger Squires) writes:
>
>	...they rode through strange forests of maguey -- the aloe
>	or century plant -- with immense flowering stalks that
>	rose forty feet into the desert air.
>
>I've seen a few of these plants when erect :) and they were no
>higher than 15 feet or so.  I think McCarthy is exaggerating and
>would like a top figure from those in the know.  Thanks bunches!


McCarthy may be right if you consider the flowering stage of the 
maguey. Flowers as tall as 10 m can be found in some semiarid 
regions. I must say that I've seen huge plants (4-5 m) but didn't see the
flowers. The stalks are used for roofs of adobe houses.

Ernesto Alvarado
 


>
>Roger Squires
>rsquires@cyclops.eece.unm.edu
>
>
>
Newsgroups: bionet.plants
From: london@calypso.uucp (Larry London)
Subject: Re: Methanol reference: PNAS 89: 9794
Organization: University of North Carolina, Chapel Hill
Date: Mon, 9 Nov 1992 14:54:15 GMT

In article <1992Nov9.133049.29911@mail.cornell.edu> Thomas Bjorkman <Thomas_Bjorkman@cornell.edu> writes:
>In article <1992Nov6.094834.1832@gnv.ifas.ufl.edu> , wcf@gnv.ifas.ufl.edu
>writes:
>>Would someone please give the reference for all this methanol 
>>discussion. I must have missed the original posting where it was given.
>
>Since many people probably want it I am posting it here.
>
>Nonomura, A.M. and A.A. Benson.  1992. The path of carbon in
>photosynthesis: Improved crop yields with methanol.  Proc. Natl. Acad.
>Sci. USA 89: 9794-9798.
>
>As a teaser the abstract begins:
>Foliar sprays of aqueous 10-50% mehtanol increased growth and development
>of C3 crop plants in arid environments.  The effects of low levels (<1 ml
>per plant) of methanol were observed for weeks after the brief time
>necessary for its rapid metabolism.
From: karen@athena.cs.uga.edu (Karen Snetselaar)
Newsgroups: bionet.plants
Subject: Re: Aspergillus niger question
Date: 12 Nov 92 23:58:41 GMT
Organization: University of Georgia, Athens

In article <1992Nov12.101737.459@ncsu.edu> samodena@csemail.cropsci.ncsu.edu (S. A. Modena) writes:
>In article <1992Nov11.172607.11998@mail.cornell.edu> Kathie Hodge <kh11@cornell.edu> writes:
>
>.....[ deleted an interesting bit on Aspergillus niger ssp. ].....
>>.............................................  They
>>haven't been known as significant agents of human disease, but they are
>>certainly facultative pathogens,  A. niger can cause a nasty infection of
>>the outer ear.
>>
>>Kathie Hodge
>>kh11@cornell.edu
>
>When I see descriptions like this, I ask: is it known whether these
>fungi contain viruses or plasmids that confer these variable/facultative
>abilities?
>
>Steve
>---

(A. niger can also cause respiratory problems, like other members of
the genus).  Human pathogenic fungi usually cause serious problems only
with immunocompromised or otherwise weakened patients.  So in this
instance, host factors may be more important than fungal variation in
explaining the "facultative" nature of the infections.

There are some instances where extranuclear elements are responsible
for fungal variation.  In _Cryphonectria parasitica_, which causes
chestnut blight, a double-stranded RNA element confers hypovirulence
(loss of infection capability) on strains that have it.  And, in
_Ustilago maydis_, a plasmid-like element carried by some strains
kills other strains.  The "Killer" strains carry a nuclear gene that
confers resistance.  I can't think of other examples, anybody else?
What role does the 2 micron plasmid found in yeast cells have in
"natural" systems?
I think there might be other reasons for apparent fungal variation too.
One might simply be our inability to distinguish among these organisms that
have few morphological characters, so they seem to us to be variable.
Also many filamentous fungi have this distressing habit of hyphal fusion
between compatible strains, and subsequent nuclear migration, so a spore or
a mycelium might contain several or many different nuclear genomes.

Karen
From: london@calypso.uucp (Larry London)
Newsgroups: bionet.plants
Subject: Re: BRIX readings
Date: 9 Nov 92 17:05:12 GMT
Followup-To: alt.sustainable.agriculture,bionet.plants
Distribution: na
Organization: UNC Office of Information Technology

Organization: University of North Carolina, Chapel Hill
Keywords: 

In article <1992Nov9.040655.24022@mprgate.mpr.ca> snider@mpr.ca (Duane Snider) writes:
>My brother is heavily into sustainable agriculture in Alberta.
>
>He was looking for information on optimal plant sugar levels, 
>specifically in cereal crops.
>
>Apparently these are called BRIX readings.  
>
>Any ideas?
>
>Duane Snider
>snider@mpr.ca
From: vanrooij@ACS.UCALGARY.CA
Newsgroups: bionet.plants
Subject: Re:  Light??
Date: 11 Nov 92 15:13:24 GMT
Distribution: bionet


the most useful rang eof wavelength that the plants use for photosynthesis
is red to far red (700 nm approx.). Hence probably any light bulb, since they
do not cut out any  part of the visible spectrum specifically, will 
support the growth. The efficiency of the light source, however, will 
depend upon the percentage of its energy given off in the above-mentioned
wavelength.
Newsgroups: bionet.plants
From: Kathie Hodge <kh11@cornell.edu>
Subject: Re: Aspergillus niger question
X-Xxdate: Wed, 11 Nov 92 12: 28:48 GMT
Nntp-Posting-User: kh11@cornell.edu
Organization: Cornell University
X-Useragent: Nuntius v1.1.1d7
Date: Wed, 11 Nov 1992 17:26:07 GMT

In article <1992Nov7.013418.8080@samba.oit.unc.edu> Larry London,
london@calypso.uucp writes:
>In article <1992Nov6.145423.1835@gnv.ifas.ufl.edu> wcf@gnv.ifas.ufl.edu
writes:
>>We are looking for information concerning the spraying of a product
>>used as biological pest control which may be contaminated with 
>>Aspergillus niger. What are the possible hazards associated with
>>this organism related to plants or animals.
>
>Isn't this the active ingredient in BEANO which is added to cooked beans
>as a digestive aid? It would also be excellent on compost piles to help
>convert raw biomass to humus. I think it breaks down cellulose & maybe
lignin.


Aspergillus niger is one of the most abundant of fungal saprobes.  There
is a whole group of species in Aspergillus (group Niger) that produce
black spores, and the taxonomy of these is difficult, so if you're
looking for further info on your contaminant, you should be sure you've
really got A. niger, and not just something in the Niger group  (see
Raper & Fennel, 1965.  _The Genus Aspergillus_ for a good, if old,
overview).

Various species have been used in industry to produce many different
compounds, including, I suspect, the active enzyme(s) in BEANO.  I don't
think the fungus itself is in there.

Although species in the Niger group grow normally as saprobes (mainly in
my frig, it seems!) they've also been reported to cause plant diseases
including peanut crown rot, cotton boll rot, onion black mold, etc.  The
spores of many species of Aspergillus are powerful allergens.  They
haven't been known as significant agents of human disease, but they are
certainly facultative pathogens,  A. niger can cause a nasty infection of
the outer ear.

Hope this helps.  

Kathie Hodge
kh11@cornell.edu
From: stuart@cosc.canterbury.ac.nz (Stuart Ralston)
Newsgroups: bionet.plants
Subject: Microbial decomposition of flowers and seeds
Date: 13 Nov 92 05:20:27 GMT
Organization: University of Canterbury, Christchurch, New Zealand


This is an abstract of my Masters thesis in Environmental Science.
Is anyone else working in this area or have any information to help
me?

Flowers and seeds are produced by most plants each year and enter
the soil system at some stage.  Ungerminated seeds and flowers are
available for enzymatic attack by micro-organisms in the soil.
This study is to quantify the amount and rate of decompostion of
a range of flowers and seeds, including native species.  Weight loss,
nitrogen mineralisation and carbon dioxide loss will be monitored 
during decomposition at various time, temperature and water regimes.
It is hoped that the results will help to gain an idea of the rate of
flower and seed decomposition, as well as nutrient turnover and soil
fertility.

Thanks in advance,

Delwyn Walker

c/o	\||||||/
	/ o  o \	   ___  ____  stuart@cosc.canterbury.ac.nz
	\ /  \ /	  /__    /   /  /	 
	 (    ) 	 ___/   /   /__/     
	  \__/
From: delwiche@sunflower.bio.indiana.edu (Charles Delwiche)
Newsgroups: bionet.plants
Subject: Re: gardening ethics? (was: Domestication of Poison Ivy)
Date: 14 Nov 92 02:45:23 GMT
Distribution: bionet
Organization: Biology, Indiana University - Bloomington

I for one would like to weigh in with those who feel this is an
interesting topic.  My own feeling is that any time one alters a
natural system one has a moral obligation to approach that alteration
in a responsible manner.  Unfortunately one person's great idea can be
another person's noxious weed.  I think we have to recognise that
mistakes will inevitably be made, and try to be forgiving of this, but
let's face it; there have been a lot of hare brained introductions,
from _Eucalyptus_ and pampas grass in California to _Opuntia_ and
cochineal bugs in Australia.  Some of these critters have caused
*serious* problems.  If a person introduces an organism to an
environment where did not previously occur, I think that person has a
moral responsibility for the effects of that introduction.  

I would also note (to play the devil's advocate) that the farming of
crops far from their native habitat has probably substantially
improved the overall standard of living for humans, both in terms of
crop yield and in terms of diversity of diet.  From what I understand,
many crops have their highest yields in areas away from their native
region.  Now, humans have caused a lot of problems around the world,
especially because there are so many of us, but I for one am glad that
high quality crops are available to as many of us as they are.

May I throw in a red herring?  The argument has often been made that
it has not been proven unsafe to continue pumping CO2 and other
greenhouse gasses into the atmosphere at the current rate.  Has it
been proven safe?  Isn't that where the burden of proof should lie?

-- 
-------
Charles F. Delwiche			(812) 855-2549
Dept. of Biology, Indiana University
Bloomington, IN 47405
From: bwilliam@oyster.smcm.edu (Bill Williams)
Newsgroups: bionet.plants
Subject: Re: Methanol reference???
Date: 9 Nov 92 17:35:11 GMT
Organization: St. Mary's College of Maryland
X-UserAgent: Nuntius v1.1.1d10
X-XXMessage-ID: <A7241A777F0101D2@williams.smcm.edu>
X-XXDate: Mon, 9 Nov 92 18:39:03 GMT

In article <1992Nov6.094834.1832@gnv.ifas.ufl.edu> ,
wcf@gnv.ifas.ufl.edu writes:
>Would someone please give the reference for all this methanol 
>discussion. I must have missed the original posting where it was
given.
>Thanks... 

I asked the same question a couple of days ago, and since at least one
other soul is as in the dark as I was I figured I'd post the response. 
Tom Bjorkman at Cornell was kind enough to mail me the answer:

Nonomura and Benson.  1992.  The path of carbon in photosynthesis: 
Improved crop yields with methanol.  PNAS 989:9794-9798.
___________________________________
William E. Williams, bwilliam@oyster.smcm.edu
Divison of Natural Sciences and Mathematics
St. Mary's College of Maryland
St. Mary's City, MD 20686
From: ARF6%manvax@CUVMB.CC.COLUMBIA.EDU ("FRANCES M. CARDILLO")
Newsgroups: bionet.plants
Subject: subscription
Date: 11 Nov 92 01:47:00 GMT
Distribution: bionet

subscribe
From: jhu@RESUNIX.RI.SICKKIDS.ON.CA
Newsgroups: bionet.plants
Subject: Textbooks and reviews
Date: 6 Nov 92 03:51:48 GMT
Distribution: bionet



Dear Plant Researchers
        I would appreciate it very much if some one could recommend me a
few recent textbooks or current reviews about (1) Genetics and
Developmental Biology of Arabidopsis and (2) plastid RNA processing of any
plants.  In order to avoid bothering other people in the network, please
e-mail to me directly.
        Many thanks to you.
        Jim Hu, Ph. D, Research Associate 
Research Institute Rm 8134
Hospital for Sick Children
555 University Avenue
Toronto, Ontario, M5G 1X8
Canada
Phone:416-813-6429
FAX:  416-813-5085
From: MEK104@psuvm.psu.edu
Newsgroups: bionet.plants
Subject: Re: gardening ethics? (was: Domestication of Poison Ivy)
Date: 13 Nov 92 21:32:03 GMT
Organization: Penn State University

jim@doink.b23b.ingr.com (James B.  Reed) in article
<1992Nov13.152842.5843@infonode.ingr.com> writes:

In article <BxMIuM.Moq@news.cso.uiuc.edu>, cl27111@uxa.cso.uiuc.edu
(ChristopherLindsey) writes:

>|>This brings up the interesting issue of ethics in gardening.  Is it
>|>ethical for people to plant species that may damage native habitats (i.e.
>|>kudzu, Purple loosestrife) if they find it attractive?  Is it ethical to
>|>plant harmful plants that have the ability to spread off of your own
>|>property, such as Poison ivy?  |> ...  |> Just thought I'd bring that
>|>up...


>Personally, I'd call the topic of ethics in gardening odd rather than
>interesting (or perhaps interesting because it's odd).  But anyway, let me
>extend your questions.

>Is it ethical for people to kill native plants if they find them
>unattractive?  Is it ethical to kill harmful plants that have sprung up
>volunteer?

>-- James B.  Reed | If at first you don't succeed, Intergraph Corporation |
>Find out why, jimreed@b23b.b23b.ingr.com | **THEN** try again.

Obviously your questions are rhetorical, but what the hell, lets make life
interesting.  It seems what you're getting at here is that its somehow wrong
for people to kill native plants that are generally considered
undesirable(?).  Like killing weeds that spring up between the cracks in
your driveway?

What Chris Lindsey was getting at is that a person (or organization) has a
responsibility to control potentially harful agents he/she has in their
care, whether that happens to be a vicious dog or a poison ivy vine.  There
are laws that force people to control vicious dogs, not so with plants.
Therefore the matter becomes an ethical one, not a legal one.



Mark Kubiske                < MEK104@PSUVM.PSU.EDU >
School of Forest Resources
Penn State University
From: ctimpte@sunflower.bio.indiana.edu (Candace Timpte)
Newsgroups: bionet.women-in-bio
Subject: joint positions
Date: 8 Nov 92 20:40:34 GMT
Organization: Indiana University


	Regarding family and jobs, my husband (who is also in science) and
I would like to consider a joint faculty position. We're both in the
fast-moving and competitive field of molecular biology and thought that
sharing a position might solve some of the research/family time dilemma.
Does anyone have information on how amenable departments are to this
arrangement, how to set it up, and will NIH fund faculty in joint 
positions? Additionally, my credientials are stronger than my spouses,
so should I apply individually and talk about the possibility of a shared
position at the interview or apply as a two-scientists-for-the-position-
of-one deal? I'm afraid we wouldn't  even be considered.
thanks,
Candace Timpte   ctimpte@bio.indiana.edu