Populations of nematodes in soils under bananas, cv. Poyo, in the Ivory Coast. V, Screening of nematicides and horticultural results

Abstract

SUMMARY Screening of fumigant and non fumigant nematicides was conducted on banana plants on the Ivory Coast between 1981 and 1984 on mineral and organic soils. The methodology used permitted separation of the effects on the growth from the effects on the harvest. This study also revealed the different components of nematode damages in banana plantations in the Ivory Coast : i) lengthening of the vegetative cycle without reduction of the total harvest; iil lengthening of the vegetative cycle and reduction of the total harvest; iii) reduction of the longevity of the plantation. These types of damages can be observed mixed in a same plantation with a severity in relation with the soil type. Nematode damage was more important on mineral soil than on organic soil. On organic soil, nematicidal and horticultural results from peat soil and Clay soil were very different, despite an apparent similar nematode community. Numerous varied relationships were found between nematode species in portion of the root system and horticultural parameters. In this study, al1 chemicals did not show an equal efficacy in reducing the nematode population, optimizing the vegetative growth and increasing the total harvest. In mineral soils, aldicarb gave the more consistent results, both from a nematological and horticultural point of view.