Cocoa is a primary source of economic income in the agricultural and agroindustrial sectors of Ecuador. However, cocoa crops are vulnerable to meteorological conditions that affect reproduction processes, including pollen production, which has encouraged the study of factors related to low crop yields and practical implications in breeding programs. The objective of this study was to assess the pollen production per flower in 11 genotypes of <em>Theobroma cacao</em> national type and CCN-51 clone. The number of pollen grains per flower was estimated by collecting 10 flower buds from each genotype for 12 consecutive months and directly counting pollen grains using an optical microscope and a Neubauer chamber. An average of 32,611 pollen grains per flower was estimated, with the largest amount of pollen (44,000) produced by the CCN-51 genotype. There was a moderate positive correlation between the environmental variables and pollen production (temperature, <em>r</em> = 0.33; <em>p</em> = 0.028; precipitation, <em>r</em> = 0.43; <em>p</em> = 0.0025). Since pollen production is an important indicator used for the selection of promising genotypes, the genotypes identified with the highest pollen production should be used in breeding programs.

Genetic improvement programs in cacao (Theobroma cacao L) have focused on obtaining new varieties with high yield and resistance to diseases. However, drought tolerance response has not been considered enough in order to face the climate change emergency. Events such as prolonged droughts or excessive rainfall can affect the pollen production of cacao flowers and others reproductive characteristics. Hence, this study was proposed to learn about the hydric deficit influence on pollen production of four Ecuadorian cacao genotypes. The results indicated statistical differences between CCN-51 and the "National" clones (P≤0.05). CCN-51 reached the highest pollen production values in the wettest treatment (26,546 ±100) compared to the “National” clones, which had no differences among them. There was a positive correlation between pollen production and the highest irrigation treatments (r=0.78), observing that while the water level was the highest, the pollen grain formation (PGF) increased, and the opposite when the water level diminished. It is concluded that the adequate water amount in the soil can increase pollen production. However, it is essential to emphasize the strong genetic influence on drought tolerance traits that could be severely affected by climatic changes. The CCN-51 and EET-575 clones should be considered when planning to develop drought-tolerant hybrids of cacao.