Comparative Characteristics of Fruits and Seeds of Guaba de Machete (Inga spectabilis) across Four Reproductive Ages in Arraijan, Panama Oeste

Francisco Corella Justavino ^1,2,*, Juan Corella Justavino ³, Félix Camarena ⁴,
José Sánchez Ávila ², Iris Arauz Moreno ^2,5, Sugely Serrano ^2,6 and Gladys Robles Nieto ^1,7
1 Unidad Socioagroalimentaria Aplicada, Centro I+D+i en Biotecnología, Energías Verdes y Cambio Climático, Facultad de Biociencias y Salud Pública, Universidad Especializada de las Américas (UDELAS), Panama City 0849-0141, Panama
2 Centro de Investigación Científica de UDELAS, Extensión Universitaria de Chiriquí, Chiriqui 0849-0141, Panama
3 Facultad de Ciencias Agropecuarias, Universidad de Panamá, Campus Octavio Méndez Pereira, Avenida José D. Fábrega, Panama City 0824, Panama
4 Facultad de Ciencias Naturales, Exactas y Tecnología, Universidad de Panamá, Panama City 0824, Panama
5 UDELAS, Extensión Universitaria de Chiriquí, Chiriquí 0824, Panama
6 UDELAS, Chiriquí University Extension, Panama City 0849-0141, Panama
7 Facultad de Biociencias y Salud Pública, Universidad Especializada de las Américas, Panama City 0849-0141, Panama
This article belongs to the Special Issue Green and Bio-based Technologies for Climate-Resilient Tropical Agriculture
* Correspondence: francisco.corella@udelas.ac.pa

Received: 20 May 2026 Revised: 29 July 2026 Accepted: 6 August 2026 Published: 25 August 2026

ABSTRACT

Inga spectabilis is a Neotropical Fabaceae tree with ecological, agroforestry, and local food relevance in Panama. However, quantitative information on the morphometric characteristics of its fruits and seeds across reproductive ages remains limited. This study compared fruit and seed traits of guaba de machete (Inga spectabilis) in Burunga, Arraijan, Panama Oeste, across four reproductive age groups: 8, 15, 22, and 27 years. Six trees were evaluated per age group, and two fruits were selected from each tree, resulting in 48 fruit observations. Fruit weight, length, width, thickness, number of seeds, seed length, seed width, seed thickness, individual seed weight, and total seed weight were measured. Data were analyzed using analysis of variance and Duncan’s multiple range test, complemented by correlation and multiple regression analyses. Significant differences among reproductive-age groups were observed for all evaluated traits. Trees aged 22 years showed the highest fruit weight, number of seeds, and total seed weight, whereas trees aged 15 years showed the greatest fruit and seed dimensions. Individual seed weight was highest in 8-year-old trees. Correlation analysis showed strong positive associations among fruit dimensions, seed dimensions, seed number, and total seed weight, while individual seed weight was negatively associated with seed number. Regression models showed strong multivariate associations among morphometric variables, although these relationships should be interpreted as exploratory rather than causal. These findings provide a local morphometric baseline for I. spectabilis in Panama and suggest that intermediate reproductive ages may be relevant for tree selection, propagation planning, and future studies integrating morphometry with productivity, germination, nutritional, and ecological analyses.
Keywords: Inga spectabilis; guaba de machete; fruit morphometry; seed traits; reproductive age; agroforestry; Panama