Firstly why are you growing Arabidopsis on a paper towel? If you are observing a rooting phenotype then the standard practice is to grow them on 1/2 MS plates which have all the nutrients they need.

This has information about the plates and seed sterilisation: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3572446/

If you are just looking at gemination rates and dont have access to sterile plates (and the ability to keep them sterile). You could technically use filter paper with some 1/2 MS solution which they would grow on (there is no reason to add a rooting hormone as they will root naturally, and adding Auxin etc would complete change the root phenotype of Arabidopsis). However because you are adding nutrients you will get contamination from bacteria/fungus if you are unable to sterilise the plates and filter paper.

With either method I would definately sterilise the seeds to remove most of the contaminants first before sowing.

I am not targeting any of the rooting DNA sequences, so, I feel confident that my decision was fine in that manner. However, I will keep an eye out for any strange bodies growing around my seeds! I will also look around at sterilizing protocols out there.   Thank you for your response!   Micah l

Hey, great question! I need to grow them on a paper towel because of

Technically all the plants need to germinate is water so placing them on a paper towel on top of soil should work. However they may have trouble penetrating the soil through the towel. But keep an eye on them for a few days after you sow them, and the germinating ones can be transferred directly onto the soil (carefully). And if they are only on the paper towel for a few days it should prevent contamination growth from occurring as well. If you decide to go down this method of transferring them I would suggest a thicker material such as filter paper to make it easier to get the young seedlings off. If you want to keep them on the paper then I would definately sterilise the seeds first to reduce contamination growth.

Also to increase your chance of germination I would do a cold incubation for at least two days (4oC fridge will be absolutely fine) directly prior to sowing.

I would contact ABRC (if you have not already) to let them know about the poor germination. They should be able to resend any seeds that did not germinate (at least thats what the European equilivant does [NASC]) and may have further suggestions.

Good luck.

Thank you so much! I have seen cold incubation two ways one wet and the other dry, but both are cold, which one would you recommend? 

I have contacted ABRC, however, they would only send me 30%. 

Again thanks!

I would recommend dry incubation over wet personally (I assume the wet incubation is just in water after being sterilised?), but both methods have been used at our University with success so it is just personal preference.

 Hey, Alison!

Great news! I was able to get they to sprout! :) You will never know how happy I am! My entire experiment rested on them sprouting! Your comments have truly helped!

And a great, very many thanks for your help!

Micah L

Brilliant, very happy to hear that! :)

So I just wanted to post this as a conclusion to this series of comments.

I found that if you are using paper towels as a sprouting medium, then for the first few hours you will have to water them a lot. I believe I watered mine every 15 minutes or so, as the soil would dry the paper out. I also found that misting them with cool (4-5C) water for a few days and then transferring over to room temperature water helped with the cold to warm snap. In the end, I watered them every 4 hours - 6 hours. I generally gave the seeds 3-6 hours of direct light, and 6-8 hours of indirect light until I saw sprouts.

The seedlings are kept under constant light (24H light 0H dark) at 23-25C. Make sure it will NEVER GO OVER 26C. I almost killed my entire stock of seedlings that way. Yes, they are that fragile. Generally the higher the temperature, the more water you should apply. For my containers, I am monitoring the water usage, so, I am using a spray bottle. I found that on minimum I need 4 pumps, just to get it damp, but for every degree above 21C I give them another pump. The paper towel will give you some grace with over-watering, but it is ruthless when under-watered, so keep them moist!

Note: Like all other growing methods, I kept the plants covered with a clear film wrap.

I used another growth container with MG potting soil mix that I sanitized ( it was sitting around for awhile) I took my container and wrapped it in black plastic, and placed it in direct light. I monitored the temperature and kept the temperature around 37-38C for about an hour. I assumed that would be enough to kill most insects that could possibly pose harm to my plants.

As of now I have 25-30 sprouts that are showing great robust growth. (I know to see many more to come!)

In all honesty, I would recommend this method of growing, as it seems to be rather successful. It is rather intensive in the beginning, but I think it poses as a viable way to sprout the seeds.

Note: I don't think the rooting hormone had any effect on the plants, so, if you are replicating this method, I would see no reason to apply it.

If you have any questions, I am willing to answer them. Though, I cannot guaranty that they are the correct way to grow them!

Micah l