# Pollen versus Pod parent



## terryros (Oct 2, 2010)

What makes crosses turn out different depending on which parent is the pod parent and which is the pollen parent? With humans, the only difference we know of is that the mother contributes the mitochondrial DNA to a child, but we aren't sure that this does most of the time unless it is faulty DNA.

I understand issues like self-pollination with Phrag fisheri and how one plant might have trouble holding on to a seed pod, but we frequently hear/see breeders talking about the plants and flowers turning out differently depending on which parent is the pod parent, even though the genetics should be the same.

What extra is the pod parent contributing to the plant?


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## PaphMadMan (Oct 2, 2010)

In addition to mitochondria, plants have chloroplasts (and other plastids) wth DNA, and all come from the pod parent in most plants, includinig orchids. These might logically affect things like general vigor, optimum temperature, optimum light, and color expression in plastids. I'm not so sure about other aspects of appearance, but there are well documented cases of maternal germ plasm effects on plants, such as male sterility in _Zea mays_, so why not things we can see too? I'm not sure how well documented it really is in orchids or any other plants, but I know some breeders rely on it. 

Can someone offer concrete examples?


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## likespaphs (Oct 2, 2010)

um, Kirk, i think you're a little confused. he asked about plant examples, not concrete examples.

oh.... i get it... you mean...
oh, forget it....

:viking:


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## hardy (Oct 3, 2010)

This was discussed in one orchid society meeting that I went to. The size and habit of some primary intergeneric hybrids in the Laeliliinae tribe can be affected by who is the pod and who is the pollen parent. I remember a primary hybrid involving Brassavola nodosa cited as an example, but forgot who's the other parent being discussed 

I've read that in some variegated african violets this trait is passed down when the female parent is also variegated. Mutation in the plastid DNA can affect formation of chloroplasts, so cause leaf variegation in some plants.

Anyone know examples with the slipper orchids?


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## hardy (Oct 3, 2010)

Ah, I just found an interesting commentary by Mr. Hsiao Ying-Chuan, the owner of In-Charm Orchids. 
I found it here: http://www.incharmorchids.com/gallery/ Great site showing some of his hybridizing directions.

He made two crosses involving Paph helenae and green complex type hybrids,
Paph In-Charm Topaz (= helenae X Pacific Shamrock) and Paph In-Charm Gold (= Emerald Magic X helenae).

http://www.incharmorchids.com/gallery/details.php?image_id=513

Here's his commentary of that In-Charm Gold and its English translation:
"用helenae交綠肉餅,目的是希望縮小植株,也希望helenae的亮黃色調能遺傳下來,看來這目標是達成了.去年底有三棵這類交配開花,不過那是用helenae當母本去交Pacific Magic,而痕煽X棵則是綠餅當母,而黃色度反而更飽滿.
本個體於10月底花蓮展時,授BM獎."

"My aim in crossing helenae with green complex type is to reduce plant size and get the yellow color of helenae. It seems that these aims have been met. Late last year there were three plants blooming from a similar cross, but in that cross helenae was used as the female parent, crossed with Pacific Magic. But for this one, a green complex type was used as the female parent, and a more saturated yellow color is obtained. 
This clone got a BM award while shown in Hualien in late October." 

Other pictures of this cross, where helenae is the pollen stud:
http://www.incharmorchids.com/gallery/details.php?image_id=566
http://www.incharmorchids.com/gallery/details.php?image_id=552
http://www.incharmorchids.com/gallery/details.php?image_id=514
http://www.incharmorchids.com/gallery/details.php?image_id=512

The pics of the other grex where helenae is the pod parent:
http://www.incharmorchids.com/gallery/details.php?image_id=430
http://www.incharmorchids.com/gallery/details.php?image_id=437
http://www.incharmorchids.com/gallery/details.php?image_id=438

I'm not sure if it's really because of the reversed role of helenae, or whether the difference in the green parents used was the key factor. Repeating the crosses with reversed order should tell.


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## NYEric (Oct 3, 2010)

Wow! There goes the grade curve!


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## PaphMadMan (Oct 3, 2010)

likespaphs said:


> um, Kirk, i think you're a little confused. he asked about plant examples, not concrete examples.
> 
> oh.... i get it... you mean...
> oh, forget it....



I'm more than a little confused, I assure you. :crazy:


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## Bob Wellenstein (Oct 3, 2010)

If the old Orchid Safari archives are around you will find information there from a talk I gave ages ago. Although copies of genes are inherited from both parents, they may not be expressed equally because of an epigenetic process called gene imprinting, whereby the gene from one parent may be inherited in an inactive form, primarily by methylation. So for some traits, the gene from the male parent may be the only one active, for others the gene from the female parent may be active. Astute breeders see these trends, and you can also manipulate them once the pollen/capsule patterns are discerned, ie the methylation or removal of methylation takes place during meiosis, so even an unexpressed (inhibited or imprinted trait) can be recovered in the next generation by the use of the appropriate cross direction. The old wives tale of traits skipping a generation has a scientific basis. I'm sure if you google "gene imprinting" or "gene methylation" you'll find some good explanations. Rob Griesbach wrote a brief article on this subject many years ago titled "Is it a mule or a hiney?". Mules and hineys are long known variants caused by gene imprinting, so some googling there may yield some interesting articles also.


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## terryros (Oct 3, 2010)

I really appreciate that scientific explanation! It really points out the value of experienced breeders who have seen crosses made both directions with different sets of parents to figure out what works best. It helps explain the great variability that we see with a number of classic hybrids. It is expensive and time consuming to acquire this knowledge, experience, and the breeding stock.


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