Effect of the Intraspecific Competition on the Fruit Yield of Guava Trees at High Density

José Saúl Padilla-Ramírez¹, Ernesto González-Gaona¹, Víctor M. Rodríguez-Moreno¹, Luis A. Díaz-García¹, and Efraín Acosta-Díaz²

1. Campo Experimental Pabellón, Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias, Mexico

2. Campo Experimental General Terán, INIFAP, Carretera Montemorelos-China, Mexico

Abstract: Mexico is one of the main guava producers at the world level with a cultivated area of 21,566 hectares and an annual fruit production of 300 thousand tons. Traditional plantation system at the producing region of Calvillo-Cañones” has been using 204 trees ha^-1 (7 ´ 7 m). Nevertheless, it has been observed a tendency to increase plant densities, as a way to increase production per unit area. However, high plant density systems could be affected by intraspecific competition (light, water, nutrients) and do not reflect a greater productivity. The objective of this work was to study the effect of the intraspecific competition on the fruit yield of guava trees established at high density. The study was conducted during three production cycles (2017-2019) at the Experimental Site “Los Cañones” which belongs to the INIFAP, located in Huanusco, Zacatecas. The following variables were registered each cycle: fruit yield, fruit number and average fruit weight. The experimental plot had four lines with 10 guava trees each one, planted at a density of 2,500 trees ha^-1 (2 ´ 2 m). Age of trees at the beginning of the study was nine years. All variables were analyzed using a randomized complete block design, as well regression analysis. The results showed that guava trees were very sensible to competition, revealed by a severe reduction on yield and fruit number up to 69%. This was attributed to the effect of the intraspecific competition among guava trees established at high density. Although, fruit size did not show a clear tendency.

Key words: psidium guajava, fruit number, fruit weight