Production of total and stainable pollen grains in Olea europaea L

The production of the total and stainable number of pollen grains per flower and per inflorescence of 13 olive cultivars ( Olea europaea L.) has been investigated. Grains stainability was evaluated by using the acetic carmine staining method whereas the production of pollen grains was calculated by using a Burker haemocytometer. All pollen characteristics taken into account varied significantly among the cultivars. The number of flowers per inflorescence ranged from a maximum of 31.3 (` Cipressino') to a minimum of 13.0 (` Leccino'), the number of pollen grains per anther ranged from 123 346 (` Arbequina') to 40 975 (` Sant'Agostino'), and the pollen stainability from 97.6% (` Cipressino') to 48.0% (` Cellina di Nardo` '). The number of stainable pollen grains per inflorescence averaged 2 559 512, ranging from a maximum of 3 913 678 (` Nociara') to a minimum of 940 143 (` Sant'Agostino'). All parameters were positively correlated, whereas a linear negative correlation was found between stainability and total pollen grains both per anther and per inflorescence.