Are Phals really Monopodial

[orchidbingo]

Originally Posted by Ray

BINGO, Terri!!!

The existence of a rhizome is the key.

Yes Ray? You called?

bingo

[RosieC]

Thanks everyone for your ideas,

and yes Howard, sometimes my mind wanders on far too complex stuff

One of my thoughts was "What is the difference between a rhizome and the connection between a monopodial orchid and a keiki"

My amateur reading of what a rhizome is just that it is a horizontal stem connecting growth points on the plant.

[RosieC]

Bingo, there must be something wrong with me, your answer didn't send me to sleep

I think I understand the differences now. Because the apical meristem does not terminate anually the levels of the hormone are too high all year round for new growth points to start.

Am I right in understanding that when the apical meristem is damaged that is when you are likely to get basil keikis (because levels of the hormone have dropped).

I remember reading here that people felt that basil keikis tended to occur when the plant seemed to sence it was in trouble and likely to die. If I have understood you correctly this could be because levels of the hormone have dropped because something is wrong with the apical meristem (not necessarily visibly damaged, but not healthy).

I hope I've understood correctly, this forum is great

[RosieC]

Bingo,

Do you know why keiki's form on the stem? Is that completely un-related or does it also relate to this hormone?

[TylerK]

Interesting discussion. Can someone explain Angraecoids to me then? Many exhibit normal monopodial growth like Phals, but I have a number that either branch or start new growths from the base without having their apical buds damaged.

Tyler

[JonnyBravo]

"Are there any other monopodials that are native to the Americas?"

yes, the three leafless species found in florida (dendrophylax, campylocentrum, and harrisella) are monopodial, as are the vanillas. there may be others, but they don't spring to mind.

[Ray]

I believe keiki formation on inflorescences is hormonal, Rosie. If it's not, the use of synthetic hormones would not "force" them, which they can.

[RosieC]

Originally Posted by Ray

I believe keiki formation on inflorescences is hormonal, Rosie. If it's not, the use of synthetic hormones would not "force" them, which they can.

Good point, should have thought of that