Page 177 - FRUTAS DEL TRÓPICO

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In this brief review, major diseases are discussed for the most important crops in Chiapas:
banana and plantain (Musa spp.), cacao (Theobroma cacao), mango (Mangifera indica), papaya

(Carica papaya), and pineapple (Anana commosus).

Space and time will not allow coverage of most diseases on these crops, although fairly

complete lists are given in Tables 1-5. Other significant crops in Chiapas can not be covered

here, including: annona, avocado, coconut, coffee, citrus, lychee, oil palm, rubber and vanilla.

Information on these and other tropical crops can be obtained from the author.

Banana and Plantain (Musa spp.)

Moko disease. Moko disease is caused by the Gram negative bacterium, Ralstonia solanacea-

rum biovar 1, race 2; it affects diverse dessert bananas, plantains and cooking bananas (Jones,

2000; Ploetz et al., 1994b). Externally, the oldest leaves in the canopy become chlorotic, wilt,

buckle and ultimately die (Ploetz et al., 1994b). Younger leaves are then affected until the
entire canopy is involved. Suckers can also be affected. When insect-transmitted strains of the

pathogen infect cushions on the peduncle, the male bud withers and darkens, and bacteria

may ooze from the bud. The fruit may turn yellow and their peel split.

Internally, affected fruit pulp is firm but brown and later gray. The vascular system in the

rhizome, pseudostem and peduncle is also discolored light to dark brown. Severed vascular

strands exude a milky discharge of the pathogen when placed in water.

Universidad Autónoma de Chiapas