Diseased plant altered genetically?
 

In another (non-gardening) forum there was a comment regarding a
possibly-diseased plant, and the potential for genetic damage as a possible
contraindication to using said plant for cuttings:

-----------------
"It really sounds like a fungal infection. You could try an anti-fungal
compound, but it's probably best to make a new cutting from the
healthy material and discard the diseased part of the plant."

"There is a possibility that the disease has affected the genetic make
up of your plant which could mean that the plant (and clones made from
it) will grow slowly forever more. You might want to consider throwing
your diseased plant away and start again with healthy cuttings."
-----------------


When the claim that "disease has affected the genetic makeup of the plant" was
questioned, this was the reply:


-----------------
"The fact that plants will mutate in order to cope with stress is well known."
-----------------


....and this reference was cited:


----------------
http://people.cs.vt.edu/~ramakris/pa...resso-Pine.pdf

"The ability of a plant to protect itself against environmental stress
is essential to its survival [Alscher et°al., 1997]. Acclimation of
plants to extreme environmental conditions or to rapid changes in
growth conditions requires a global cellular response and changes in
the expression of many genes. Exposure to extremes of light intensity
and temperature, drought, and some herbicides can cause the downstream
formation of reactive oxygen species (ROS). ROS may be present in the
form of superoxide (O2—), hydrogen peroxide
(H2O2), or the hydroxyl ion (OH—). ROS, especially OH—, are toxic
because they can oxidize any macromolecule in the cell
[Scandalios°(ed.), 1997]. This potential threat to cellular function
can cause protein unfolding, the inactivation of enzymes, DNA damage,
mutation, lipid peroxidation, and consequent disruption of cell
membrane function.
--------------------


Since then, I've been pondering this, and searching for further references
without much success. What I'm wondering in particular is how one judges when a
stock plant is so unhealthy as to make propagating from it a bad idea because
of the possibility that mutations have occurred which would cause the clones to
grow poorly.

Obviously propagating from healthy plants is the best course of action; but I'm
interested in this from a theoretical point of view as well, as I hadn't been
aware that clones could be affected in this way.


Does anyone have comments or links to references on this subject? or is there a
better newsgroup in which to ask this?

Thanks!
Bill

Diseased plant altered genetically?
 

It is well known that many garden plants that have long been propagated
vegetatively from single clones have over the years become virus infected
and have lost their original vigor as a result. The problem is that the
infection can be spread to other plants due to unsanitary garden practices
and such insects as aphids and mealy bugs. There is still no cure for virus
diseases in plants. The curious thing is that the same virus can express
itself different ways in different species. Not all virus diseases express
themselves as distorted leaves or variegation and many times the plants
appear to show no unusual symptoms at all. Viruses are not spread through
seed propagation but most cultivars will only come true when propagated
vegetatively. Therein lies the dilemma.



VoySager wrote in message
...
In another (non-gardening) forum there was a comment regarding a
possibly-diseased plant, and the potential for genetic damage as a
possible
contraindication to using said plant for cuttings:

-----------------
"It really sounds like a fungal infection. You could try an anti-fungal
compound, but it's probably best to make a new cutting from the
healthy material and discard the diseased part of the plant."

"There is a possibility that the disease has affected the genetic make
up of your plant which could mean that the plant (and clones made from
it) will grow slowly forever more. You might want to consider throwing
your diseased plant away and start again with healthy cuttings."
-----------------


When the claim that "disease has affected the genetic makeup of the plant"
was
questioned, this was the reply:


-----------------
"The fact that plants will mutate in order to cope with stress is well
known."
-----------------


...and this reference was cited:


----------------
http://people.cs.vt.edu/~ramakris/pa...resso-Pine.pdf

"The ability of a plant to protect itself against environmental stress
is essential to its survival [Alscher et°al., 1997]. Acclimation of
plants to extreme environmental conditions or to rapid changes in
growth conditions requires a global cellular response and changes in
the expression of many genes. Exposure to extremes of light intensity
and temperature, drought, and some herbicides can cause the downstream
formation of reactive oxygen species (ROS). ROS may be present in the
form of superoxide (O2-), hydrogen peroxide
(H2O2), or the hydroxyl ion (OH-). ROS, especially OH-, are toxic
because they can oxidize any macromolecule in the cell
[Scandalios°(ed.), 1997]. This potential threat to cellular function
can cause protein unfolding, the inactivation of enzymes, DNA damage,
mutation, lipid peroxidation, and consequent disruption of cell
membrane function.
--------------------


Since then, I've been pondering this, and searching for further references
without much success. What I'm wondering in particular is how one judges
when a
stock plant is so unhealthy as to make propagating from it a bad idea
because
of the possibility that mutations have occurred which would cause the
clones to
grow poorly.

Obviously propagating from healthy plants is the best course of action;
but I'm
interested in this from a theoretical point of view as well, as I hadn't
been
aware that clones could be affected in this way.


Does anyone have comments or links to references on this subject? or is
there a
better newsgroup in which to ask this?

Thanks!
Bill

Diseased plant altered genetically?
 

It is well known that many garden plants that have long been propagated
vegetatively from single clones have over the years become virus infected
and have lost their original vigor as a result


Is the loss of vigor due to effects of the virus passed on from the parent to
the clone, though, rather than to some change in the genome? I always
understood it to be the former.

Diseased plant altered genetically?
 

In general, the concept of genetic response to environmental stress died with
Lamarck. That said, the answer to the question is a resounding: anything is
possible.
I certainly would caution people against trying to reproduce a diseased plant,
unless it is the only one of its kind left in the world.
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)

Diseased plant altered genetically?
 

Hello, this is a first for me, but it is full of subjects I now a good
bit about! In reality there is no way that a cutting from your
diseased plant would be genetically altered. The DNA damage you
mention is on a single cell level and is random. Most mutations are
fatal, and therefore the damaged cell would die. If it didn't die it
would still be only one cell out of a billion or so. The reason for
not using diseased material is to avoid spreading disease, mostly
viral. The only way to get rid of a viral disease is to do meristem
cloning and get lucky.... out of the means of most folks.
Now if you were to do (agghhhhh an over 40 moment! I can't recall
the term!) the type of cloning (using the meristem, and seperateing it
to single cells) that they do in labs now you could create a
genetically altered plant from the scenario you laid out... reactive
ox. sp. causing DNA damage..... it would be shot inthe dark.... but
that is one way to get a new/unusual clone ie in orchids.
I will stop here as I feel myself on a ramble through
bio/genetics..... there are lots of interesting permutations of
this...if you are a nerd.:)

ostheap (VoySager) wrote in message ...
In another (non-gardening) forum there was a comment regarding a
possibly-diseased plant, and the potential for genetic damage as a possible
contraindication to using said plant for cuttings:

-----------------
"It really sounds like a fungal infection. You could try an anti-fungal
compound, but it's probably best to make a new cutting from the
healthy material and discard the diseased part of the plant."

"There is a possibility that the disease has affected the genetic make
up of your plant which could mean that the plant (and clones made from
it) will grow slowly forever more. You might want to consider throwing
your diseased plant away and start again with healthy cuttings."
-----------------


When the claim that "disease has affected the genetic makeup of the plant" was
questioned, this was the reply:


-----------------
"The fact that plants will mutate in order to cope with stress is well known."
-----------------


...and this reference was cited:


----------------
http://people.cs.vt.edu/~ramakris/pa...resso-Pine.pdf

"The ability of a plant to protect itself against environmental stress
is essential to its survival [Alscher et°al., 1997]. Acclimation of
plants to extreme environmental conditions or to rapid changes in
growth conditions requires a global cellular response and changes in
the expression of many genes. Exposure to extremes of light intensity
and temperature, drought, and some herbicides can cause the downstream
formation of reactive oxygen species (ROS). ROS may be present in the
form of superoxide (O2â€"), hydrogen peroxide
(H2O2), or the hydroxyl ion (OHâ€"). ROS, especially OHâ€", are toxic
because they can oxidize any macromolecule in the cell
[Scandalios°(ed.), 1997]. This potential threat to cellular function
can cause protein unfolding, the inactivation of enzymes, DNA damage,
mutation, lipid peroxidation, and consequent disruption of cell
membrane function.
--------------------


Since then, I've been pondering this, and searching for further references
without much success. What I'm wondering in particular is how one judges when a
stock plant is so unhealthy as to make propagating from it a bad idea because
of the possibility that mutations have occurred which would cause the clones to
grow poorly.

Obviously propagating from healthy plants is the best course of action; but I'm
interested in this from a theoretical point of view as well, as I hadn't been
aware that clones could be affected in this way.


Does anyone have comments or links to references on this subject? or is there a
better newsgroup in which to ask this?

Thanks!
Bill

Diseased plant altered genetically?
 

The reason the economy became so robust had nothing to do with Clinton.
It was because the introduction of technology, which increased the
productivity of each individual making companies show a great profit to
pay taxes on. He was just lucky because by history, the greatest tax
increase he gave us, (so we had less of our own money), normally would
have been a disaster.

jcart003 wrote:
Hello, this is a first for me, but it is full of subjects I now a good
bit about! In reality there is no way that a cutting from your
diseased plant would be genetically altered. The DNA damage you
mention is on a single cell level and is random. Most mutations are
fatal, and therefore the damaged cell would die. If it didn't die it
would still be only one cell out of a billion or so. The reason for
not using diseased material is to avoid spreading disease, mostly
viral. The only way to get rid of a viral disease is to do meristem
cloning and get lucky.... out of the means of most folks.
Now if you were to do (agghhhhh an over 40 moment! I can't recall
the term!) the type of cloning (using the meristem, and seperateing it
to single cells) that they do in labs now you could create a
genetically altered plant from the scenario you laid out... reactive
ox. sp. causing DNA damage..... it would be shot inthe dark.... but
that is one way to get a new/unusual clone ie in orchids.
I will stop here as I feel myself on a ramble through
bio/genetics..... there are lots of interesting permutations of
this...if you are a nerd.:)

ostheap (VoySager) wrote in message ...

In another (non-gardening) forum there was a comment regarding a
possibly-diseased plant, and the potential for genetic damage as a possible
contraindication to using said plant for cuttings:

-----------------
"It really sounds like a fungal infection. You could try an anti-fungal
compound, but it's probably best to make a new cutting from the
healthy material and discard the diseased part of the plant."

"There is a possibility that the disease has affected the genetic make
up of your plant which could mean that the plant (and clones made from
it) will grow slowly forever more. You might want to consider throwing
your diseased plant away and start again with healthy cuttings."
-----------------


When the claim that "disease has affected the genetic makeup of the plant" was
questioned, this was the reply:


-----------------
"The fact that plants will mutate in order to cope with stress is well known."
-----------------


...and this reference was cited:


----------------
http://people.cs.vt.edu/~ramakris/pa...resso-Pine.pdf

"The ability of a plant to protect itself against environmental stress
is essential to its survival [Alscher et°al., 1997]. Acclimation of
plants to extreme environmental conditions or to rapid changes in
growth conditions requires a global cellular response and changes in
the expression of many genes. Exposure to extremes of light intensity
and temperature, drought, and some herbicides can cause the downstream
formation of reactive oxygen species (ROS). ROS may be present in the
form of superoxide (O2â€"), hydrogen peroxide
(H2O2), or the hydroxyl ion (OHâ€"). ROS, especially OHâ€", are toxic
because they can oxidize any macromolecule in the cell
[Scandalios°(ed.), 1997]. This potential threat to cellular function
can cause protein unfolding, the inactivation of enzymes, DNA damage,
mutation, lipid peroxidation, and consequent disruption of cell
membrane function.
--------------------


Since then, I've been pondering this, and searching for further references
without much success. What I'm wondering in particular is how one judges when a
stock plant is so unhealthy as to make propagating from it a bad idea because
of the possibility that mutations have occurred which would cause the clones to
grow poorly.

Obviously propagating from healthy plants is the best course of action; but I'm
interested in this from a theoretical point of view as well, as I hadn't been
aware that clones could be affected in this way.


Does anyone have comments or links to references on this subject? or is there a
better newsgroup in which to ask this?

Thanks!
Bill

Diseased plant altered genetically?
 

jcart003 wrote:

In reality there is no way that a cutting from your
diseased plant would be genetically altered. The DNA damage you
mention is on a single cell level and is random. Most mutations are
fatal, and therefore the damaged cell would die. If it didn't die it
would still be only one cell out of a billion or so. The reason for
not using diseased material is to avoid spreading disease, mostly
viral.



So, if I understand you correctly, the statement:

"There is a possibility that the disease has affected the genetic make up of
your plant which could mean that the plant (and clones made from it) will grow
slowly forever more. You might want to consider throwing your diseased plant
away and start again with healthy cuttings."

....is essentially untrue? And that, in the case of viral disease, a clone from
an infected plant would be affected by the virus, but not by any genetic
mutation that might have been caused in the parent plant by the virus?



Now if you were to do (agghhhhh an over 40 moment! I can't recall
the term!) the type of cloning (using the meristem, and seperateing it
to single cells) that they do in labs now you could create a
genetically altered plant from the scenario you laid out... reactive
ox. sp. causing DNA damage..... it would be shot inthe dark.... but
that is one way to get a new/unusual clone ie in orchids.


Tissue culture? So, in fact, from what you're saying, it takes a purposeful
attempt to cause mutation in the parent cells that would get passed on to the
clones, and even then it's an iffy proposition?

I see from your address that you're an educator or researcher? so I could quote
your response as a professional opinion from a knowledgable individual? (I
don't want to pry and ask you to identify yourself...)

Better yet, do you have any suggestions as to sources of info (links) on this
subject, preferably not too technical? I did a little bit of reading on the
subject of adaptive mutation today that would seem to question whether, in
fact, "the concept of genetic response to environmental stress died with
Lamarck", as Iris said earlier; but I couldn't even begin to try to argue that,
as I'm a dirt gardener, not a scientist.



I will stop here as I feel myself on a ramble through
bio/genetics..... there are lots of interesting permutations of
this...if you are a nerd.:)



Or, for that matter, ramble on if you wish, I at least will read your response;
I'm no nerd, I'd have to know more about the subject to even aspire to that
status ;-) , but as I said before, I was surprised at the statement above
regarding "disease-mutation-affecting-growth", doubted its veracity, and would
like to learn enough about the subject to be able to refute it.

Thanks for all the responses (except for yours, bayhill ["The reason the
economy became so robust had nothing to do with Clinton." etc.]... you're lost
in the wrong thread).

Bill

Diseased plant altered genetically?
 

Diseased plant altered genetically?
 

a key concept, GERMLINE vs SOMATIC(this may
truly only be an animal term but the concept is the same). For a trait
to be passed on it must be in the germ line, that is sex cells. While
you can clone plants easily, the original mutation had to occur in the
germ line, for the reasons I tried to get across in my first response,
a mutation in the somatic cells is only in a single cell and the
trait/cell would not be able to multiply enough to take over the whole
(unless you go to a single cell tissue culture scenario)......


That's a very clear explanation right there, thanks for your help!

Bill