Pollen Production in Theobroma cacao L. Genotypes National Type and CCN-51 and Its Relationship with Climatic Factors on the Ecuadorian Coast

Abstract

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.

The potential impacts of climate change on ex situ conservation options for recalcitrant-seeded species

“…Interestingly, the months with the highest pollen production and rainfall also have the highest air temperatures. In this sense, it is important to understand the interactions between air temperature and soil moisture since an adequate water supply becomes critical to ensure adequate pollen production when temperatures rise (García-Cruzatty et al, 2020;Mena-Montoya et al, 2020).…”

Análisis de competitividad del destino turístico y el desarrollo de las rutas del cacao ecuatoriano

“…Con más de un millón de hectáreas de producción en Ecuador, según la Asociación Nacional de Exportadores e Industriales de Cacao del Ecuador (ANECACAO, 2021), actualmente el cultivo de cacao se realiza en varias provincias ubicadas en la región amazónica, litoral y andina (Espinoza, 2020); y gracias a la oportunidad económica y social que brinda este tipo de producto natural a la comunidad, o a la empresa encargada de su cultivo, se considera el desarrollo de proyectos turísticos alternativos que permiten dar a conocer las características, bondades y beneficios de las variedades del cacao que existen en el país, entre ellos, el Cacao CCN-51 (cacao clonado de origen ecuatoriano) y el Cacao Nacional Arriba o «Cacao Arriba» (ANECACAO, 2015; García-Cruzatty et al, 2020). A partir de un producto turístico denominado Ruta, en este caso del cacao.…”

Is Pollen Production of Birch Controlled by Genetics and Local Conditions?

“…Most studies on pollen production of woody plants are limited to genera or species. Yet, a small number of studies have focused on the intraspecific level, for example, related to Cupressus sempervirens varieties [18] or Theobroma cacao clones [19]. Although Adams and Kunze [20] studied clonal variations in seed production in spruce, there has been little discussion on pollen production of genetically identical trees.…”