Abstract Detail



Ecophysiology

Cocoletzi , Eliezer [1], Hipólito , Enrique  [1], Ricaño , Jorge [1], Ramos, José María [1].

Structure and function of cocoa agroforestry systems in Mexico: relation of functional traits with trees production.

Cocoa (Theobroma cacao L.) is a species distributed in the humid tropics, cultivated traditionally in agroforestry systems. With this research, we determined the morphological and structural response of four cocoa clonal varieties established in three experimental plots under agroforestry conditions in Veracruz and Oaxaca states of Mexico. It was made the agroecological characterization of shade trees and it was measured the microclimatic conditions of cocoa trees. The experimental design were randomized blocks with five replications per plot, clonal variety and light treatment (sun, shade). The shade conditions in Rancho Papayal are mainly determined by Fraxinus sp.; in Nuevo Ojital by Citrus sinensis; and in Cerro Camarón by Cedrela odorata. The shade trees intercept up to 85.9% of the photosynthetic active radiation and the canopy of cocoa trees intercept up to 59.3%. After five years of the cocoa trees establishment, the high vapour pressure deficit conditions in plots with low light interception by shade trees are related with cocoa trees are under higher water stress. The low shade conditions diminish the growth of the cocoa plants during the first five years after establishment, reducing their height and basal diameter. The higher shade conditions in Rancho Papayal favored the positive relation with the SLA. The cocoa plants in Nuevo Ojital with higher photosynthetic active radiation favor high vapour pressure deficit and increase the water stress, this affect the cocoa development since in the first stages of development the plants need more shade that favors optimum water conditions, as is the case of Rancho Papayal and Cerro Camarón. The condition of greater shade in Nautla, has favored the growth of the plants, increasing their height, diameter and foliar area. Based on our results, we can better understand the morpho-anatomical responses of cocoa in agroforestry systems.


1 - Universidad Veracruzana, Centro de Eco-Alfabetización y Diálogo de Saberes, Av. de las Culturas Veracruzanas, Xalapa, VE, 91060, Mexico

Keywords:
Photosynthetically active radiation
vapour pressure deficit
specific leaf area
Stomata
clonal varieties.

Presentation Type: Oral Paper
Number: 0007
Abstract ID:155
Candidate for Awards:None


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