Semi-Determinates your experience ??

[maf]

Also, I don't know if this has been mentioned in this thread without going back and looking, but it has I think been mentioned at this site before:

In other plants, such as the tomato, the first stem terminates rather early. A lateral branch will take over and grow out for several nodes. Soon this branch terminates (often after a strict number of nodes bearing leaves) and a lateral branch takes over, and so on. In this kind of plant, the main axis is composed of many lateral branches, and is called sympodial.

In other words each stem terminates after it flowers and what appears to be the continuation of the stem is actually a lateral shoot.

From: http://www-plb.ucdavis.edu/labs/rost...branching.html

[maf]

Originally Posted by NarnianGarden

I would doubt that - even though I have seen all kinds of strange growth patterns. Why would pruning into one main branch change the genetics?

You are probably right, but I am going to see how it works with reference to my post above about sympodial growth.

[travis]

Originally Posted by maf

Also, I don't know if this has been mentioned in this thread without going back and looking, but it has I think been mentioned at this site before:


In other words each stem terminates after it flowers and what appears to be the continuation of the stem is actually a lateral shoot.

From: http://www-plb.ucdavis.edu/labs/rost...branching.html

I think it compounds confusion to call the typical continuation of a single, primary meristem "a series of lateral shoots" whether it is a biological fact or definition.

If we were to do so, then the already confused issue of what we call "suckers" or "side shoots" or "secondary stems" or those other stems that emerge LATERALLY from the crotch of a leaf node, becomes even more confusing.

The issue of what is a semi-determinate is made clear in the paper linked on page 1 by MAF. Read the paper. Then go count the internode spacings on your indeterminates vs determinates ... and on your semi-determinates if you happen to have one or two.

[BlackBear]

Originally Posted by travis

I think it compounds confusion to call the typical continuation of a single, primary meristem "a series of lateral shoots" whether it is a biological fact or definition.

If we were to do so, then the already confused issue of what we call "suckers" or "side shoots" or "secondary stems" or those other stems that emerge LATERALLY from the crotch of a leaf node, becomes even more confusing.

The issue of what is a semi-determinate is made clear in the paper linked on page 1 by MAF. Read the paper. Then go count the internode spacings on your indeterminates vs determinates ... and on your semi-determinates if you happen to have one or two.

Very Interesting !,

There still seems to be some notion of being able to extend production in either

determinates / or determinates with the "semi " expression .


The extension of production by manipulation or direction of energy/growth into the suckers/lateral /secondary by culture.

I am inductively thinking that the determinates with the "Semi" are more flexible and extendable .......but of course will eventually terminate .

I still think that the "Semi " expression could be useful / flexible to extend production.

[zipcode]

Originally Posted by maf

I read an anecdotal post somewhere once that determinate plants can be grown pruned to a single stem, greenhouse style, and when grown in this fashion the main stem does not terminate but continues growing indefinitely. I have been meaning to try it out myself and see exactly how it works.

I actually tried that by mistake. I had some mystery tomatoes that I got from the agronomical University as 'really productive' (turns out it was really sensitive to septoria and didn't produce that much for me). A few plants stopped after 5 some after 7 clusters, but they did stop. I don't know after how many they would have stopped have I not pruned them however. They had clusters after 2 leaves, but I didn't bother looking at the time for some reason, I kinda just assumed they were indeterminate for some reason.

[travis]

There is no mistaking a determinate tomato plant.

Look at the photo. See the lower flower cluster? The one with the two little fruit sets indicated by my fingers?

That is the flower cluster set upon the "internode" space on the meristem between two leaf nodes.

Then see the next flower cluster immediately above the one with the fruit set? That flower cluster emerged on the leaf petiole exactly where the subsequent extension section of apical meristem SHOULD HAVE or WOULD HAVE emerged IF the plant were an indeterminate.

However, the plant is a DETERMINATE, hence the TERMINAL FLOWER CLUSTER has terminated the forward and upward growth of that meristem. Hence the plant is DETERMINATE.

Here is another example of DETERMINATE



In that photo, you can see the same pattern on the primary meristem (main stem or initial growing stem that was transplanted into the ground) BUT then you see a side shoot, or secondary shoot ... a "clone" branch that has emerged from the crotch of a leaf node. This side shoot will repeat the exact same pattern of flowering and eventually ALSO TERMINATE with the exact same terminal flower pattern as did the primary stem ... a flower cluster on a leaf petiole where the apical meristem would grow upward IF THE PLANT WERE INDETERMINATE.

But since the plant instead is a DETERMINATE, there is no extension upward with the apical meristem because the terminal efflorescence emerged there instead of the meristem extension.

EDIT: These two examples happen to be: first photo: (Cherokee Purple x Summerpink) F2, where I was selecting for determinate expression; and photo #2: (Monte Verde x Neptune) F1, a hybrid cross of two open pollinated determinate tomato varieties.

[BlackBear]

Originally Posted by maf

It confused me for years, but basically the semideterminate gene, sdt, is a modifier of the determinate habit and has no effect on indeterminate plants. The determinate varies between 1 and 2 nodes between flower clusters, whereas the semi-determinate always has 2.

From http://hortsci.ashspublications.org/.../1074.full.pdf

I like the description ......

so the determinate varieties with consistently 1 leaf between inflorences would be considered Compact ?


and 2 leaf between inflorescences "regular " determinate ? (up to 5 inflorescences)



and the 2 leaf with 6 + inflorescences that eventually terminate are the Semi expression .

does anybody know which semi varieties in fact have more "Programed" inflorescences ??

where possibly would we find that out ???




and of course all the above is to be distinct from "Dwarfness" where the space between the internodes is about half of the regular spacing .


This is where one can have a small Compact cultivare that fits in a container that is Not actually a dwarf.

So one can have dwarf-compact determinate , dwarf -regular determinate , dwarf-semi determinate and dwarf-indeterminate ??


Does anyone know of an actual dwarf "Semi-determinate " ??

[travis]

Here is another clear example of a terminus efflorescence on a determinate plant.



When you see this or similar arrangement, where a flower cluster (efflorescence) emerges where the ascending apical meristem extension would have emerged on an indeterminate, then you are looking instead at a determinate plant.

[bower]

Just a word of caution, but, I'd be careful not to read too much into the results of a single study, which looked at exactly three varieties and one example each of 'determinate' , 'semi-determinate' and 'indeterminate'. I think other permutations are possible and even common perhaps, if people bothered to count the internodes between clusters who are growing or have grown a great number of heirloom or OP varieties, I think it would be clear.
As regards the question "where would one possibly find that out?" afaik the answer is in your own garden, with the tedium of counting internodes and clusters.

The number of leaves between clusters is variable in indeterminates as well as the others. I have two examples of indeterminates growing this year, with 5 or more leaves between the first and second clusters (Ukraine Purple and Snickers).
Also, Zolotoe Serdtse (semi-determinate) has six or seven clusters on the main stem, with only one leaf between clusters, not two.
Bursztyn has two leaves between clusters but so far no sign of a terminal bud, so perhaps that is to come, however it is listed in some places as 'indeterminate'.

So I think it would be rash to make assumptions about or based on the number of leaves between clusters, observed in one study of three varieties.

As Travis has said repeatedly, the DISTINGUISHING factor for a Determinate plant is that the main stem (and side shoots too) form terminal buds instead of getting longer and longer.

Semi-Determinate is a type of determinate, ie it also forms terminal buds but has a longer main stem and more clusters, by the present definition six or more.

As regards the dwarf question, yes it is genetically distinct (one or more dwarfing genes are possible), and unrelated to the sp or sdt genes, so you can have any combination of dwarf with the other growth habits.

Originally Posted by BlackBear

I like the description ......

so the determinate varieties with consistently 1 leaf between inflorences would be considered Compact ?


and 2 leaf between inflorescences "regular " determinate ? (up to 5 inflorescences)



and the 2 leaf with 6 + inflorescences that eventually terminate are the Semi expression .

does anybody know which semi varieties in fact have more "Programed" inflorescences ??

where possibly would we find that out ???




and of course all the above is to be distinct from "Dwarfness" where the space between the internodes is about half of the regular spacing .


This is where one can have a small Compact cultivare that fits in a container that is Not actually a dwarf.

So one can have dwarf-compact determinate , dwarf -regular determinate , dwarf-semi determinate and dwarf-indeterminate ??


Does anyone know of an actual dwarf "Semi-determinate " ??

[Redbaron]

Originally Posted by bower

Just a word of caution, but, I'd be careful not to read too much into the results of a single study, which looked at exactly three varieties and one example each of 'determinate' , 'semi-determinate' and 'indeterminate'. I think other permutations are possible and even common perhaps, if people bothered to count the internodes between clusters who are growing or have grown a great number of heirloom or OP varieties, I think it would be clear.
As regards the question "where would one possibly find that out?" afaik the answer is in your own garden, with the tedium of counting internodes and clusters.

The number of leaves between clusters is variable in indeterminates as well as the others. I have two examples of indeterminates growing this year, with 5 or more leaves between the first and second clusters (Ukraine Purple and Snickers).
Also, Zolotoe Serdtse (semi-determinate) has six or seven clusters on the main stem, with only one leaf between clusters, not two.
Bursztyn has two leaves between clusters but so far no sign of a terminal bud, so perhaps that is to come, however it is listed in some places as 'indeterminate'.

So I think it would be rash to make assumptions about or based on the number of leaves between clusters, observed in one study of three varieties.

As Travis has said repeatedly, the DISTINGUISHING factor for a Determinate plant is that the main stem (and side shoots too) form terminal buds instead of getting longer and longer.

Semi-Determinate is a type of determinate, ie it also forms terminal buds but has a longer main stem and more clusters, by the present definition six or more.

As regards the dwarf question, yes it is genetically distinct (one or more dwarfing genes are possible), and unrelated to the sp or sdt genes, so you can have any combination of dwarf with the other growth habits.

If that's right, then what I have been calling semi-determinates all these years is actually semi-indeterminates, and vice versa.

[bower]

Originally Posted by Redbaron

If that's right, then what I have been calling semi-determinates all these years is actually semi-indeterminates, and vice versa.

EH... it's not what you call em, it's how you grow em that matters....
I'll be standing in for the "sp" gene myself shortly, when the burly indets get as high as I'm lettin em. .. their main stem will surely terminate, regardless.
.... speaking of which, do tell me, how do you manage the Snickers growth habit? Do you prune and train it or let it bush wildly or...???? It's the wierdest thing I've ever seen - six internodes between clusters, but very short internodes, and yow, the suckers that are bushing up off that, but long ones with ten leaves before any buds... And shaping up to be tall, afaict, also....

[travis]

As a follow-up comment to one issue being discussed ...

It doesn't really matter what you call a particular growth pattern because what you arbitrarily decide to call it does not define it in fact. I think we all should have learned that by now after years of what seed company catalog blurbs have incorrectly or irresponsibly designated as the growth habit of so many varieties.

On a side issue, yes I think there are more regulating or modifying genes than those so far identified as indeterminate, determinate, and semi-determinate. They just haven't been fully explored and designated with abbreviating letters.

[NarnianGarden]

Gold digger, uhh, Gold nugget has only one leaf between the flower trusses... efficient way of maximizing the growing time?

[Redbaron]

Originally Posted by bower

EH... it's not what you call em, it's how you grow em that matters....
I'll be standing in for the "sp" gene myself shortly, when the burly indets get as high as I'm lettin em. .. their main stem will surely terminate, regardless.
.... speaking of which, do tell me, how do you manage the Snickers growth habit? Do you prune and train it or let it bush wildly or...???? It's the wierdest thing I've ever seen - six internodes between clusters, but very short internodes, and yow, the suckers that are bushing up off that, but long ones with ten leaves before any buds... And shaping up to be tall, afaict, also....

Yes, snickers is a VERY wild and wooly beast!

I only grew them one year. I let them run wild and just kinda hemmed them in with a Florida weave. They produce a WHOLE lot of foliage, AND a whole lot of tomatoes. Which is probably why they handled the summer heat here without any problems. The foliage protected the fruit from sun scald even when temps got over 100 degrees.

Because of the later fruit set (started with many leaves as you noted), at first I was concerned, but later when they get going I had TONS of tomatoes. Making sauce almost every day with them!

[BlackBear]

Originally Posted by bower

Just a word of caution, but, I'd be careful not to read too much into the results of a single study, which looked at exactly three varieties and one example each of 'determinate' , 'semi-determinate' and 'indeterminate'. I think other permutations are possible and even common perhaps, if people bothered to count the internodes between clusters who are growing or have grown a great number of heirloom or OP varieties, I think it would be clear.
As regards the question "where would one possibly find that out?" afaik the answer is in your own garden, with the tedium of counting internodes and clusters.

The number of leaves between clusters is variable in indeterminates as well as the others. I have two examples of indeterminates growing this year, with 5 or more leaves between the first and second clusters (Ukraine Purple and Snickers).
Also, Zolotoe Serdtse (semi-determinate) has six or seven clusters on the main stem, with only one leaf between clusters, not two.
Bursztyn has two leaves between clusters but so far no sign of a terminal bud, so perhaps that is to come, however it is listed in some places as 'indeterminate'.

So I think it would be rash to make assumptions about or based on the number of leaves between clusters, observed in one study of three varieties.

As Travis has said repeatedly, the DISTINGUISHING factor for a Determinate plant is that the main stem (and side shoots too) form terminal buds instead of getting longer and longer.

Semi-Determinate is a type of determinate, ie it also forms terminal buds but has a longer main stem and more clusters, by the present definition six or more.

As regards the dwarf question, yes it is genetically distinct (one or more dwarfing genes are possible), and unrelated to the sp or sdt genes, so you can have any combination of dwarf with the other growth habits.

I grew Burstyn last year and it was billed as an indeterminate and early ...

of course I never got to go looking for terminal bud .....at the time ....

let me know if it is in fact a semi and you confirm a terminal bud it sure was an interesting

one .......


I didn't know Zolotoe Serdtse (semi-determinate) has six or seven clusters on the main stem, with only one leaf between clusters, not two.
Sounds like a nice relatively compact plant loaded with fruit ... compared to an actual indeterminate .