How important is seed orientation/direction?

Question

What are the effects of different seed orientations on germination and further development? Could it make a significant difference in germination rate, survival, or even growth rate?

I wonder how useful it could be to point all seeds so that they emerge "up" in the soil, vs randomly placing them.

This question isn't tied to any specific type of plant. I imagine some species may not care, and perhaps for others it may even be critical.

@GrahamChiu - Okay. Do you have any data? Have you ever experimented yourself? — Bort, Apr 06 '18 at 18:05
Everytime I plant a seed I ignore orientation, and they all come up. — Graham Chiu, Apr 06 '18 at 18:08
@GrahamChiu - I am in the middle of researching this topic, and I'm seeing two answers. One is that of your own, which is mostly people saying: *"It doesn't matter because plants grow up and that's all there is to it. There is no need to think deeper."* and the other answer: *"Seeds lose energy when the root and stem have to curve to re-orient the plant."* But I'm not sure how that untimely affects a plant. — Bort, Apr 06 '18 at 18:11
If you haven't used the scientific method on seed orientation, I don't think you would be able to compare the different orientations, because you didn't write them down. What appears as small, random differences in height or time to break soil surfaces could be a product of seed orientation. — Bort, Apr 06 '18 at 18:12
If you're asking such minute detail then this is off topic and should be asked on biology.Se — Graham Chiu, Apr 06 '18 at 18:24
@GrahamChiu - I'm not asking for a cellular level analysis. I'm just asking if anyone knows the affects of seed orientation. The absence of evidence is not the evidence of absence. If no one contributes any knowledge, I'll answer this myself. — Bort, Apr 06 '18 at 20:40
You have the accumulated wisdom of millennia of farmers which you wish to question. One of the purposes of the seed is to provide enough energy to produce cotyledons, and then photosynthesis takes over. If eg a bean seed is placed flat or pointed along its long axis is insignificant in terms of growth distance to reach the surface being only a couple of MMS more distance to travel. Other cultural matters are far more important in the long term. — Graham Chiu, Apr 06 '18 at 22:22

score 3 · Answer 1 · answered Apr 06 '18 at 22:04

Usually seeds have a flattened shape, so when you plant them oudoors they will fall with the flat surface towards the soil, not on their the edge. Other seeds have a round shape, so it doeasn't matter anyway how it lands. Think of cereal and vegetable seeds that are sown on large lots, they fall from a sewing device attached to a tractor and they sprout just fine.

What I noticed about germination is that large seeds sown on shallow containers need to be helped to lose the small debris from the seedcoat, or to be sown deeper so that the seedling could use the soil to get rid of the seedcoat.

VividD · Answer 2 · 2018-04-18T16:24:36.190

According to the article Seed Orientation During Planting Improves Germination, orientation affects germination, for some species.

The key seed feature related to the orientation is the location of so called radicle, the place where the root emerges from the seed. The radicle can be easily recognized only for some species. An example of such species is pumpkin. It is generally better if the radicle is at the lowest point in the soil.

This is schematics drawing of Salix scouleriana's seed: (however, since this seed is very small, taking care of its orientation while sowing is practically impossible; but the image is included for illustrative purpose, to visually explain the radicle part in general)

(the drawing is in public domain; it is created by Suzanne Foster @ USDA-NRCS PLANTS Database)

That article seems to be opinion with no data. If orientation were important evolution would have taken care of it. — Graham Chiu, Apr 20 '18 at 00:58

How important is seed orientation/direction?

2 Answers2