Pollen fertility test by acetocarmine stainability
- Collect at least 3 mature flowers per plant.
- Place one drop of 1% acetocarmine on a slide glass.
- Put the pollen slightly on the acetocarmine drop using a vibrator (an electric toothbrush without a brush part is convenient).
- Leave for 1 minute, and then gently place a cover slip.
- Observe al least 200 pollen grains under a microscope. Count the numbers of well-stained pollen grains and unstained, aborted pollen grains.
Note: Pollen stainability less than 5% is classified as male sterile. Plant which has more than 1% of 2n pollen is considered as a 2n pollen producer.