hand emasculation of sunflowers

So you want to do some crosses without CMS or relying on self incompatibility? It takes some dedication but it can be done! This is how I carry out hand emasculations. There are hormone based options out there but they can need background specific protocols.

  1. Grow your plants.
  2. Bag the heads you want to use when there is 2-3cm between the last leaf and the head. Don’t bag too early and don’t bag too many leaves this will make the head grow crooked.
  3. Show up ~30 minutes after sunrise or when the greenhouse lights come on. There is variation here with the temperature effecting when the anthers come out of the florets. You can usually figure out the right time to come in a few days. If you show up to early you will only be able to see the very tips of the anthers as the come out of the corolla. These are very difficult to remove. Waiting 15-30 minutes will make a big difference. You will also notices some lines progress at different rates than others.
  4. Use a set of tweezers like these: http://www.aventools.com/avens-complete-product-line/tools/tweezers-and-quick-test-tweezers/precision-tweezers-1/e-z-pik-precision-tweezers/e-z-pik-tweezers-7-orange#.UzxaJ63c-d8 to remove that days new anthers. See figure for about where and when you should grab the anthers. You can grab a few at a time. You will notice as the morning progresses the pollen at the top of the anther will start to come out and fall all over the place. I find there is about a 1 hour window which is optimal.
  5. Use a good spray bottle set to a ‘jet’ spray (not mist) and spray down the head. This step is very essential.
  6. With the head wet inspect it for anther fragments either still in the corolla or fallen down in between florets. Repeat steps 4+5 as needed.
  7. Repeat steps 3-6 until the flower is done. I find this is about 1 week to ten days for a large cultivar head. If you don’t want to wait for the every floret you can use the forceps or a knife to remove the center florets.