Question about seed coats.

In following Baolvera's thread about the old seeds, I started wondering about seed coats.

Do seed coats offer anything else to embryo seedlings other than protection against dehydration?

Could you remove a seed coat and just plant the embryo?

Are the shapes, structure, color and thickness of seed coats indicative to the plant genus?

Do seeds always have the same ph as the parent plants?

X

X, In ref to "Could you remove the seed coat and just plant the embryo?"
I have left mine in water so long, that the whole blooming, pun intended, thing
has floated free from the seed case. I planted it and it did just fine as I recall.
Must have been a larger seed because sometimes the small ones will just rot.
Maybe you could test one or two seeds. This was in the spring when they naturally
want to germinate. Don't know what would happen if this is attempted during the cold months or if it makes any difference what season.
Jackie

This message was edited Dec 12, 2006 2:04 PM

I've noticed on some that I started in coffee filter that the seed coat had removed itself.

Yess............. there are other species and genera that need the grinding through the seed coat to germinate..... From some seed found in Egyptian toumbs, after 3000 years, the seed cases were ground through and they germinated after 3000 years. With Morning glories, I have a lot of confidence in there tenerity because of their seed coats. Their biological imperitie to disperse
the see over time allowed, must mean that the mgs have a longgggg seed life. Frank

Some thoughts...

The seedcoat protects the vulnerable embryo from physical and environmental trauma...including excessive dehydration and pathogenic processes...

When the seedcoat absorbs enough water,the seedcoat will swell,soften and sometimes slough off and this may or may not initiate germination,but will often allow for an increase in the passage of gaseous as well as potential pathogenic organisms...an atypical(!) off-season rain may not contain the mineral and other naturally occuring component ratios that may stimulate seeds to germinate...mineral cations all have their own specific electrical charges of various degrees...there are reports in the literature that indicate that seeds may be more sensitive to micro-electical charges than previously thought to be the case...

Plants,animals and all forms of life on this planet have evolved in relation to iron bio-magnetism(naturally magnetic iron known as magnetite) which renders all forms of life sensitive to magnetic and electro-magnetic radiation...
Dr.Joseph L. Kirschvink discovered the Iron bio-magnetism reception in all living organisms and his continued researches have continued to strongly influence our understanding into the complexities of all forms of life relative to (electro) magnetic reception responsiveness...

The time of year that seed germination is attempted may play a crucial role in the ultimate success or failure of seed(s) to germinate...especially in germination sensitive situations...

See JLHudsons page on germination factors and strategies
http://www.jlhudsonseeds.net/Germination.htm


The seeds can often be variously and surprisingly sensitive to hydrostatic pressure...Jacqumontia tamnifolia are an excellent example of this..hydrostatic pressure may or may not be one of the 'obscure' factors in initiating seed germination...What role the seedcoat plays in hydrostatic water sensitivity remains to be clarified...


Abscisic acid(ABA) is the main germination inhibitor in many seeds...

There are 2 schools of thought regarding the useage of different sprouting environments for seeds to reduce potential pathogenic organisms...

1) the sterile approach where there is a concerted effort to reduce the total amount of potential environmental organisms >including pathogens that will destroy the embryo by useage of a variously sterile environment...sterile approaches can often be substantially assisted by the useage of specialized plant growth hormones as would be used by a botanist familiar with performing tissue culture reproduction...


2) the usage of well matured compost which will may often contain micro-organisms that will not readily feed on fresh plant material,but is more inclined to feed on organic material that has already been variously well decomposed...these micro-organisms compete with and often suppress organisms that have more of an appetite for fresh living material like embryos...

Sometimes one approach will work where the other may not...plants form special mycorrhizal relationships in conjuction with mycorrhization helper bacteria (MHB),with beneficial organisms that assist the roots to absorb nutrient and metabolism modifying substances...every plant family,genus,species and even individual plants form special rhizosphere microflora and microfauna relationships that can vary in specificity from very general to exceptionally specific to each(!) individual plant...these symbiotic relationships exert a profound influence on the chemistry of the entire plant by modifying and modulating many chemical equations at and around the environment of the roots...

The seedcoat is usually generally more beneficial than detrimental,but there are particular circumstances where the removal of the seedcoat is likely to result in better germination results...and the sum total of the environmental characteristics will be the determining factor...including the readiness state of the embryo to germinate ...

I have successfully grown embryos that were removed from the seedcoat > especially if I sensed that an anaerobic problem was likely to be present,but I definitely prefer to allow the seedcoat the protect if at all possible...

The seeds that have only partial seedcoats are certainly more susceptible to physical trauma and more likely to be eaten by pathogens than seeds with intact seedcoats...

I have used homemade 'artificial' seedcoats to preserve embryos that had damage to the natural seedcoats...this has worked out well for me...

Seedcoat characteristics can often be used to help assist in ascertaining a plant identity if you are especially (already!) familiar with the exact seedcoat characteristics of a particular species,but size,thickness,shape and other structural features can vary considerably even within the same genus...

Generally speaking,MG's tend to have a long shelf-life,but the very large thick-shelled seeds have a much longer shelf-life than the regular ornamental types...Kew gardens was asked to participate in sprouting seeds from tombs that were several thousand years old...not one of the seeds germinated...I am personally not aware of any professional peer reviewed literature that substantiates that seeds over several thousand years old have sprouted,but it might be so...


Seeds generated from a particular plant may have a tendency to be closer to the ph of the parent plant, but the parent also tries to provide a chemical formula that has been proven by the genome to yield the most likely chances of germination and survival...



There are several basic groups of micro-organisms

1) 'strictly' aerobic
2) 'strictly' anaerobic
3) microbes that are able to flourish in environments that are not strictly aerobic nor strictly anaerobic,but able to flourish in environments that tend to be more aerobic or anaerobic

Aerobic organisms are most often the more beneficial to germinating seeds and more developed growing plants,although some plants e.g.,have developed the ability to flourish in stagnant hypoxic bogs where anaerobes may predominate

The soluble fiber component of the seeds is known to have certain properties and functions including the following

1) The soluble/fermentable fiber components present in the seed will respond to adequate hydration by forming a variously gelatinous mucilaginous pectinaceous glucan containing covering which may be eaten by specific fungi and produce natural anti-biotics which help to further protect the young sprout...> symbiotic biocompatiility...

2) the hydrated soluble fiber components bind with water and may continue to maintain essential hydration of the embryo after any initial external water source has slackened and pending further hydation and tissue growth > the gel-like material often have a soothing emolient effect on the embryo which allows the seedcoat to slough off without unnecessary damage to the cotyledons and > additionally protects the embryo from premature dehydration with the addition of having certain thermal and EM radiational insulating properties


The soluble/fermetable fiber components present in the seed may also otherwise variously contain fermentable
mucopolysaccharides now called > glycosaminoglycan,Oligo- or polysaccharides,Oligofructose,arabinose,Inulin and fructans
which are often be eaten by pathogens which may not be of any benefit to the plant embryo and simply cause a state of anaerobiasis and associated hypoxia with further decomposition of the plant embryo...


the solution at one stage can often become the problem at another stage and vice versa...it's a question and matter of tiimg and interaction with all overall circumstances...



Some 'advanced' but still relevant questions include

1) does the gelatinous material directly or indirectly contain substances or compounds that stimulate germination(?)...

2) are there sources of GA's that most closely match the GA's most commonly found in Ipomoea seeds(?)

3) have induced magnetic fields been used to successfuly germinate difficult to germinate Ipomoea seeds(?)


Hope my offerings will be of some value...

TTY,...

Ron

This message was edited Jan 18, 2007 10:46 PM

Wow and thanks! Your reply has prompted more questions, but i need to re-read and assimilate what you wrote. It has also made me re-think the way I germinate seeds. I tend to treat them all the same way and have about a 90% success rate since I started using ProMix BX instead of soil. Damping off has never been a problem for me except in 2 instances that I can recall.

Many people are horrified by the fact that I use the same growing medium and pot all season long to germinate all of my seeds. I'm beginning to wonder if my success rate might be due some of the beneficial organisms attracted to seedcoats that are present and multiply in the re-used medium. It seems to me by the middle of summer, seeds start to germinate faster and stronger. This spring, I will use two pots. In one I will re-use the growing medium and the other I will use new with each batch and divide the seeds into each and see if I get different results.

The growing medium I use is ProMix BX which has been innoculated with mycorrhizal fungi. I stopped using soil 3 years ago and have been astonished by the difference in seed germination and plant growth.

You have given me a lot of food for thought!

Thanks!

X