Methods
Twelve cacao (Theobroma cacao) clones propagated by grafting were evaluated by USDA-ARS at the Corozal Agricultural Experiment Station of the University of Puerto Rico (Corozal clay; clayey, mixed, isohyperthermic Aquic Haplohumults) and evaluated for 6 years of production under intensive management. The soil has a pH of 4.47, NH4-N 83 mg/kg, NO3-N 74 mg/kg, phosphorus 10 mg/kg, potassium 353 mg/kg, calcium 1293 mg/kg, magnesium 79 mg/kg, iron 146 mg/kg, manganese 19 mg/kg, zinc 0.26 mg/kg, aluminum 144 mg/kg, and 1.41% organic carbon. The 64-year (1948–2012) mean annual rainfall is 1905 mm and Class A pan evaporation is 1433 mm. Mean monthly maximum and minimum temperatures are 29.9 (C) and 19.5 (C), elevation, 195 m.
Twelve cacao (Theobroma cacao) clones propagated by orthotropic rooted cuttings of somatic embryo-derived plants were evaluated by USDA-ARS at the Corozal Agricultural Experiment Station of the University of Puerto Rico (Corozal clay; clayey, mixed, isohyperthermic Aquic Haplohumults) and evaluated for 6 years of production under intensive management. The soil has a pH of 4.47, NH4-N 83 mg/kg, NO3-N 74 mg/kg, phosphorus 10 mg/kg, potassium 353 mg/kg, calcium 1293 mg/kg, magnesium 79 mg/kg, iron 146 mg/kg, manganese 19 mg/kg, zinc 0.26 mg/kg, aluminum 144 mg/kg, and 1.41% organic carbon. The 64-year (1948–2012) mean annual rainfall is 1905 mm and Class A pan evaporation is 1433 mm. Mean monthly maximum and minimum temperatures are 29.9 (C) and 19.5 (C), elevation, 195 m.
Type grown in Costa Rica. Bartley, 1993a (BAR93A). Pittier, 1902a (PIT02A) states that MATINA refers to the Criollo type that was first cultivated in the area. MATINITA refers to introduced material with Amelonado shaped pods of Amazon Type. However, Soria says MATINA refers to the introduced Amazon material with Amelonado pods.
The USDA-ARS Tropical Agriculture Research Station's Theobroma cacao collection was field characterized in Mayaguez, PR over five years (2007-2011). Characterization efforts focused on highly discriminating phenotypic traits in addition to agronomic traits of importance (e.g., length, width and weight of pods, diseased pods and pod index) and these were recorded for all accessions being evaluated. Cacao trees were established in a randomized complete block design in 2001 in a full sun, irrigated, pruned, fertilized and highly managed orchard. Trees were planted in a diamond pattern with two meters between trees and rows with a three meter alley between every second row for equipment. All accessions were grafted onto Amelonado rootstock. Evaluations began in 2007, when the trees were approximately six years old. Both phenotypic and agronomic traits were measured in an attempt to efficiently distinguish among genetically similar clonally propagated accessions as well as to identify some of the accessions with promising agronomic potential.
The USDA-ARS Tropical Agriculture Research Station's Theobroma cacao collection was field-characterized in Mayaguez, PR, over five years (2019-2024). The characterization focused on highly discriminating phenotypic traits and agronomic traits of importance (e.g., length, width, and weight of pods, diseased pods, and pod index), recorded for all evaluated accessions. Cacao trees, established in a randomized complete block design in 2001, were cultivated in a full sun, irrigated, pruned, fertilized, and highly managed orchard. Trees were planted in a diamond pattern with two meters between trees and rows, with a three-meter alley between every second row for equipment use. All accessions were grafted onto Amelonado rootstock. Evaluations began in 2019 with already established mature trees. Both phenotypic and agronomic traits were measured to efficiently distinguish among genetically similar clonally propagated accessions and to identify accessions with promising agronomic potential.