Evaluation of Pollen Production of Common Male Date Palms Grown in the Mexicali Valley, Mexico

The aim of this study was the evaluation of date palm ( Phoenix dactylifera L.) pollen production during the 2021 and 2022 seasons in the Mexicali Valley, Mexico. Twelve seed-propagated male palms of 20 years of age and similar vigor were selected and grouped into four groups with phenotypic characteristics of the common female cultivars in the area (Medjool, Deglet Noor, Khadrawy, and Zahidi). The pollen was extracted manually, with average production among all individuals of 780.94 and 777.11 g, in 26 and 24 inflorescences, respectively, for each year. Likewise, the flowering period on average was 47 and 41 days for each year. The pollen extracted from the earliest four inflorescences averaged 38.7 and 32.55 g, while that of the latest one produced 10.70 g and 18.28 g for each year, respectively. Seedling male palms with a phenotype similar to the Deglet Noor cultivar produced the greatest amount of pollen with 1250.98 and 1114.26 g on average for each year, produced during a late, short flowering period. Likewise, those palms with phenotypes similar to the Medjool cultivar produced the second-highest amount of pollen with 851.28 and 866.43 g on average for each year, produced during an early, long flowering period. Finally, an in vivo viability test through the fruit set percentage, revealed that the use of any of these four pollen sources would be suitable for the pollination of the recipient female cultivar Medjool, the most widely cultivated variety in Mexico. These results will allow date producers to select and propagate better pollen-producing male palms.