INCIDENCE OF LETHAL DISEASES IN PARENTAL AND HYBRID PLANTS OF COCONUT IN TABASCO, MÉXICO

Abstract

Incidence of lethal diseases in plantations of Pacific Tall and, Malaysian Yellow Dwarf coconut palm, and thrir hybrid was determined. In two mother plantations located 80 km away from the coast in Tabasco, the Pacific Tall and Malaysian Yellow Dwarf varieties were evaluated, whill in 4 plantations located along the coast, 15 km away from each other in Centla and Paraiso, the evaluation for the hybrid population was carried out. Samplings were taken every 15 days. Each hybrid plantation averaged 100 trees from which 30 were chosen at random. The number of diseased trees was the quantified variable. The symptoms were described and causal agents detected in each diseased tissue. The diseases detected were Red Ring (Bursaphelenchus cocophilus) with an average incidence of 18.1 % for hybrids trees and less than 2% for their parents. It was also detected initial and differential symptoms between genotypes. Ceratocystis wilt (Cladosporium sp; Graphium sp.) showed an average incidence of 27.5, 28.8 and 7% for the hybrids, Pacific Tall and Malaysian Yellow Dwarf, respectively. Stem Bleeding (Thielaviopsis paradoxa) and Bud Rot (Phytophthora sp.) incidence was low.