ABC model of flower development well as in the determination of the floral meristem. Therefore, the "AG" mutants are devoid of androecium and gynoecium and they have petals and sepals in their place. In addition, the growth in the centre of the flower is undifferentiated, therefore the petals and sepals grow in repetitive verticils. The "PLENA" ("PLE") gene is present in "A. majus", in place of the "AG" gene, although it is not an ortholog. However, the "FARINELLI" ("FAR") gene is an ortholog, which is specific to the development of the anthers and the maturation of pollen. In "Petunia", "Antirrhinum" and in maize the C
Pollen count Pollen count Pollen count is the measurement of the number of grains of pollen in a cubic meter of air. High pollen counts can sometimes lead to increased rates of an allergic reaction for those with allergic disorders. Usually, the counts are announced for specific plants such as grass, ash, or olive. These are tailored to common plants in the measured areas. Mild winters with warmer days lead to an increase in pollen counts while colder winters lead to delayed pollen release. In the UK, the public announcement of the pollen count was popularised by Dr. William Frankland, an immunologist.