Allometric models based on measurements of single leaf dimensions or a combination there are useful tools for determining individual leaf area (LA) because they are non-destructive, precise, simple and economical methods. The present study was carried out at the Central Station Naranjal of Cenicafé, located in the Department of Caldas (Colombia), four models were defined using the variables length (L) and/or width (W) to estimate LA in coffee leaves of the Castillo^® variety (Coffea arabica L.). Estimation of regression coefficients was performed using information recorded from 6,441 leaves (group 1), and their validation was performed using records from another 992 leaves (group 2). Leaves were collected from all strata of the canopy and ranged from 0.76 to 140 cm² in LA. In addition to exhibiting coefficients of variation differing from zero based on t-tests at 1%, the evaluated models possess coefficients of determination between 0.93 and 0.99. Four expressions have developed and adjusted to estimate leaf area in individual leaves, based on the measurement of simple variables and non-destructive.

A finales de 1960, el programa de mejoramiento genético de Cenicafé inició el desarrollo de variedades resistentes a la roya del cafeto, altamente productivas, con el perfil de taza característico del café de Colombia, porte bajo, uniformidad fenotípica razonable y adaptabilidad. Consciente de los actuales requerimientos de los caficultores colombianos, en Cenicafé, se desarrolló la nueva variedad Cenicafé 1, que posee como características un porte tipo variedad Caturra resistente a la roya y a la enfermedad de las cerezas del café, producción igual y porcentaje de café supremo mayor que la variedad Castillo. Para el desarrollo de esta nueva variedad se evaluaron progenies avanzadas provenientes del cruzamiento entre la variedad Caturra y el híbrido de Timor 1343; dichas progenies se establecieron en la estación experimental Naranjal de Chinchiná - Caldas, y se verificó su comportamiento en las estaciones experimentales de Pueblo Bello - Cesar, El Rosario - Antioquia, Paraguaicito - Quindío y El Tambo - Cauca.

Soil waterlogging is an environmental limitation that is promoted by changes in rainfall patterns and negatively affects plant physiology, growth, and development, coffee production, and exports in Colombia. The objective of this research was to evaluate responses in growth, water status, and chlorophyll fluorescence parameters for plants under different waterlogging conditions. The evaluations were carried out on six-month-old “Cenicafé 1” variety seedlings that were suitable for establishment in the field. The seedlings were subjected to different waterlogging periods: 4, 8, 12, and 16 days, using a completely randomized block experiment design with 30 replicates. Total dry mass (TDM), total leaf area (TLA), and the total number of leaves (TNL) were performed, and growth indices were calculated. The leaf water potential (Ψ_pd and Ψ_md), maximum efficiency of photosystem II-F_V/F_m, and electron transport rate (ETR) were also measured. Waterlogging for 16 days caused a 57% reduction for TDM, which was significant starting at 4 days. Statistical differences in the TLA were detected after 12 days, with decreases of 29%. The Ψ_pd, Ψ_md, F_v/F_m, and ETR were sensitive to waterlogging, which decreased noticeably after 8 days. The results indicated the physiological performance and growth of the coffee cv. “Cenicafé 1” plants were significantly affected by waterlogging conditions after eight days.

In Coffea arabica L., the processes of flowering and fruiting unfold over time as a series of phenological events influenced by both biotic and abiotic factors. This sequence governs the plant’s reproductive cycle, directly affecting vegetative growth, crop productivity, and beverage quality. This review comprehensively addresses the developmental phases and provides descriptions of flower and fruit morphology, factors influencing flowering and fruiting, and competition for resource allocation, all of which are approached from a phenological perspective informed by the extended Biologische Bundesanstalt, Bundessortenamt and CHemical industry (BBCH) scale. The structural and emerging challenges that affect the sustainability of coffee cultivation should be effectively addressed to provide a foundation that supports the design of integrated strategies for the optimization of agronomic practices, increased yield, and genetic improvement.

The phenological patterns of coffee flowering in Colombia have typically been studied in a descriptive way, with knowledge from an inferential perspective being scarce. The present study evaluated the effect of geographic location and accession on the floral patterns and phenological descriptors of Coffea arabica L. Fifteen accessions from the Colombian coffee collection (four tall and eleven short) were planted in the departments of Cesar, Caldas, Quindío and Cauca (Colombia). The number of flower buds per branch per plant per evaluated accession was recorded weekly during four flowering semesters. Subsequently, the phenological flowering descriptors, namely synchrony among individuals, intraindividual temporal variability and number of events were calculated. The data were analyzed descriptively, and then the inferential component was conducted using analysis of variance for a two-factor additive model and randomization restriction. The results showed that there are two flowering patterns according to the expression of flowering in the floral cycles, the “annual” class in the department of Cesar and the “continual” class in the departments of Caldas, Quindío and Cauca. The phenological descriptors show differences between the departments according to the coffee zone to which it belongs (northern, central or southern). In turn, the floral pattern of each area can be linked to the latitudinal change in daily sunshine, as well as to the distribution of rainfall and temperature, in a very broad sense and based on the literature. The data did not provide statistical evidence to suggest differences among the accessions or between the tree sizes evaluated.

Coffee production between the first and second harvest presents a difference in the fruit load with the plant age that could affect the leaf gas exchange. This research aimed to evaluate the effect of the increase in fruit load that occurs between the first and second harvest of the Coffea arabica L. production cycle on the measured gas exchange, at the two phenological stages of the fruit. The accessions E057, E318, E338 and E554 were used, as well as a completely randomized design, with three replications, using the accessions as treatments and the harvest measurements during the production cycle as the repeated measures. The variables yield per tree, number of fruits, absolute growth rates for height and stem, leaf area, leaf-to-fruit ratio and leaf gas exchange were measured across the phenological stages of fruit filling and ripening. The increase in the fruit load that occurs with age in the second harvest, if compared to the first harvest, showed a positive and significant effect on the net assimilation rate that was not expected for the obtained leaf-to-fruit ratios. Likewise, the differences in the assimilation rates were higher during the fruit-filling stage. This result suggests that the source-sink relationship may vary with the crop age and fruit phenological stage, and is not entirely depend on the leaf-to-fruit ratio.