Foliar diseases of the trees in the Tezozómoc Cultural and Recreational Park, Azcapotzalco, Distrito Federal

Abstract

In view of the interest to preserve the Tezozómoc Cultural and Recreational Park (TCRP) due to the environmental benefits that it provides to the fauna that lives in it as well as to society, a phytosanitary diagnosis of its trees was performed and the physical and sanitary conditions of the trees were examined in order to determine their current status. 10 % of the total dominant species were sampled, and all the individuals of the associated species were considered. Botanical materials were collected for their determination and for their analysis based on pathological signs and symptoms. Pathogens were found in adult trees. 3 758 trees were counted, belonging to 30 species or varieties grouped into 16 families; 67 % (20) of these trees are evergreen, and the remaining 33 % (10) are deciduous. The most abundant species and those with the largest cover were Eucalyptus camaldulensis, Populus tremuloides, Pinus radiata var. binata, Fraxinus uhdei, Schinus molle and Cupressus lusitanica, which is indicative of little diversity. Nine of these species exhibited foliar damage from various fungi; five of these –particularly Fusarium– are characterized by chlorotic mottling. The necrosis observed in Erythrina coralloides and Fraxinus uhdei is related to Alternaria sp. The most prevalent fungi and their hosts were Phoma glomerata in Acacia retinoides and Alternaria alternata in Fraxinus uhdei, both present in all the individuals, and Melampsora epitea, occurring in 90 % of the Salix babylonica specimens. A potential association between the ash flower eriophyid Aceria fraxiniflora in Fraxinus uhdei and the Fusarium sporotrichioides micromycetes fungus has recently been reported.