Survey of Root-Inhabiting Microorganisms on Declining and Nondeclining Breadfruit (Artocarpus altilis) in Jamaica

Abstract

A survey of phytoparasitic nematodes, fungi, and bacteria associated with roots of breadfruit (Artocarpus altilis) trees was conducted in Jamaica in 1991. Eighteen trees sampled did and 12 did not exhibit decline, characterized by premature fruit drop, leaf chlorosis and abscission, general unthriftiness, and branch dieback. Most trees of each category were parasitized by dense populations of Pratylenchus coffeae. Helicotylenchus erythrinae, H. multicinctus, and Meloidogyne incognita also occurred within roots in large populations. Fusarium species (F. equiseti, F. oxysporum, F. pallido-roseum, and F. solani) were detected frequently. Pseudomonas spp. occurred in most root samples, and all roots had vesicular-arbuscular mycorrhizae. Physical and chemical characteristics of the soil and nutrient concentrations within leaves were not relatable to tree health. Most trees exhibiting decline symptoms were more than 20 years old.