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Response of the Abelmoschus esculentus to the Root Knot Nematode

Meloidogyne incognita

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D. Pechimuhtu and J. Shoba
Department of Zoology, V.O.Chidambaram College, Thoothukudi – 8, Tamilnadu.
Email of corresponding author: raja.d.pechimuthu@gmail.com

ABSTRACT
The root-knot nematodes Meloidogyne spp. are the most common and important group of

plant pathogens, which attack the majority of major crops. Because of their complex

interaction with host plants, large host range, and the extent of damage caused by infection,
nematodes are at the top of the list of the most economically and scientifically important

organisms. They’re endoparasites with mature females that lodge and develop within the
roots of certain cultivated plants, causing productivity losses. It affects the host's metabolic

function, resulting in physiological and biochemical changes in the infected host.

Abelmoschus esculentusis one of the most important crops. Many diseases, including those
caused by plant-parasitic nematodes, may reduce their yields. In this study, the root-knot

nematode Meloidogyne incognita was used to study the reaction of okra, Abelmoschus
esculentus (Malvaceae). The morphological and biochemical analyses of the inoculated and

non-inoculated okra plants followed (control and 30 days after inoculation). Root galling and
stunted growth was the results of the nematode infection. The carbohydrate metabolism of the

host plant, A. esculentus, was investigated. The overall sugar and starch contents in the root

and shoot system were found to be decreased as a result of nematode infection. Chlorophyll
concentration was also found to be lower. The functions of other enzymes were also shown to

be reduced. Β–amylase activity was found to be reduced. The root-knot infection was found
to have a significant impact on the host plant's carbohydrate metabolism.

Key Words: Meloidogyne incognita, Abelmoschus esculentus, Stunted Growth,

Chlorophyll, β–amylase.
INTRODUCTION

Meloidogyne incognita, a root-knot nematode, causes significant harm to several
economically important crops (Kofoid and white,1919;Chitwood,1949). This economic

impact on agricultural productivity has been extensively demonstrated (Webster, 1972).

Plants that are highly infested are stunted and show signs of nutritional inadequacy, in
addition to a decrease in fruit output. The characteristic of knotting or galling of the host

plant roots for development and reproduction of Root-knot nematodes is the most visible

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