Were all of the bulbs the same size when you planted them

Yes, these are seedlings of 2010 germination.
A

Hi Arif,
It is great to have you back to the forum. I reason that it is a combination of both genetics and competition. There is certainly a genetic component. As you have almost certainly witnessed, some crosses yield faster-growing seedlings than others, due to genetic difference And even if they are all from the same cross, there will should be genetic differences in growth rate among siblings, but probably not as much as there is between one cross and another.
When plants are grown in competition with each other, these genetic differences tend to become accentuated, particularly when competing strongly for light. The faster seedlings will initially be a bit taller and with larger leaves so they intercept more of the light and cast more shade on their neighbors. This allows them to produce more food at the expense of the neighbors. As time goes on, the larger plants get a larger and larger fraction of the light (the rich get richer and the poor get poorer). So modest genetic differences can get magnified through time. This is one of the reasons why agriculture commonly relies on nearly genetically uniform seeds. This same thing can happen due to competition for water or nutrients, but generally not to the same extent as with competition for light.

Bill

Bill, thank you, Logical and acceptable. A separate bed is the solution. Tomorrow they will have a bed of their own. Let the handicapped compete with each other.
Arif

Arif,

This happens to me all the time. Four or five siblings in a pot, one or two will grow much more quickly than the others and they will be all different sizes; same conditions; food, light, & water. I would think genetics play the biggest role after all like children, they most always come out different. I do think that the runts will eventually grow and bloom, they just need a few more years.

Donna

This post was edited by dondeldux on Tue, Feb 4, 14 at 11:36

Arif...I agree with Bill and Donna that this can be caused by heredity or malnorishment or both. I would like to add though that this can likewise be caused by the virus in your garden.

I agree with Donna and Bill.

Awesome picture! What a great illustration of the growth rates. I don't have anything to add about why this happens, but have also noticed the same thing and will be very interested in how your new bed does - will the runts suddenly grow faster with less competition?

I do not see in the photo features, confirming the presence of a viral infection. But clearly shows the genetic difference between seedlings. Here's a look: the most extreme range of top-down 3 large bulbs beside, then the 2nd horizontal row below: 3, 4, 5 and beside the bulb is the smallest 2. And so on.

O

For those who do not know...yet anyway. Arif has bred some of the most beautiful hybrids in his lovely garden in Pakistan. Unfortunately, a few years back his hippeastrums got the virus and due to his age and health, he has chosen not to destroy them and let them be. That is the reason why I was suggesting that the virus "can" also be the cause of difference in bulb size/health. Judging/Studying non-virused plants are totally different from virused ones.

Below is a link for those who would want to read up about this.

Here is a link that might be useful: Arif's Virused Plants in 2011

135 one and a half inch diameter bulbs have been given a separate bed, lets wait for April 2015 for the result.
Arif

Today I took out the seedlings of 2013 sowing for transplanting in a bed.
The size varied as illustrated below (the seedlings are from the same pot),Genetic is what comes to my mind.
{{gwi:380222}}From Amaryllis 2014

Now the are in a bed, large one on one side smallest on the other and the medium in between.
We will have to wait for another two years for the result.
Arif

Interesting, Arif. I would hypothesize that, if given the same size bulbs, the same conditions, in 2 years we will see the same bulb size differences because of variability in genetics. I will be waiting.

Marie

Good visual! Looking forward to hearing how the experiment goes.