Nematodes are small animals or roundworms which belong to the phylum Nematoda(Hodda, 2011). They are various parasitic and non-parasitic nematodes habiting a very broad range of environments and causing damage to plant. Though this Nematode species can be difficult to distinguish, and although over 25,000 have been described,( Zhang,2013). of which more than half are parasitic, the total number of nematode species has been estimated to be about 1 million(Lambshead, 2012). Unlike the phyla Cnidarians and Platyhelminthes (flatworms), nematodes have tubular digestive systems with openings at both ends. Nematodes have successfully adapted to nearly every ecosystem. They are found in virtually every environment, both as parasites and as free-living organisms. They are generally minute, but some species can reach several meters in length. Plant parasitic nematodes, which are very small or microscopic, can cause significant damage to crops, and are extremely widespread. Maize(Zea may L) which is grown extensively in temperate, subtropical and tropical -regions of the world are some of the plant which are easily damaged by plant parasitic Nematod. As part of cereals maize constitute the world’s most important food crops. This is due to their great adaptability, permitting successful colonisation in every type of ecological habitat; relative ease of cultivation; tillering habit giving higher yield per unit area; and good nutritive values (Vasil, 2011).
Among cereals, maize (Zea mays) occupy the most eminent positions in terms of production, acreage and source of nutrition, particularly in developing countries like Nigeria (CIMMYT, 2010). Maize is one of the major staple in many rural and urban communities of Nigeria and has also recently been identified as one of the non-traditional cash crops(Nnemeka,2010). Maize(Zea may) has one of the cereal is faced with problem of plant parasitic nematode which has being one of the source of damage to cereal plant like maize.
Plant-parasitic nematodes differ greatly in the complexity of their life cycle. The type of reproduction differs among and within nematode groups. Most parasitic species reproduce sexually: copulation between a male and a female is required to fertilize eggs produced by the female. Fertilized eggs hatch to release a vermiform (worm-shaped) juvenile stage. Juveniles molt several times before a final molt results in an adult male or female. However, in some species, males are rare or unknown, and the females reproduce through a process called parthenogenesis (Greek for “virgin birth”), in which eggs are produced and become viable without being fertilized. The time period required to complete a full life cycle varies greatly among species. Though plant parasitic nematodes are among the economically important pests of crops and are prevalent in cultivated as well as uncultivated fields. Continuous monoculture may result in a build-up of nematode population which may remain stable for many years (Oostenbrink, 2012). In conditions favourable for rapid nematode population increase, severe crop damage may occur resulting in yield losses. Based on this background this study therefore investigates the prevalence of and effect of plant parasitic nematode on maize plant in Awka Metropolis.
The broad objective of this study is to investigate investigates the prevalence of maize parasitic nematode in Awka. Specific objectives of the study is to (1) The prevalence of maize infestation by parasitic nematode in Awka (2) The type of parasitic nematode responsible for maize damage in Awka.
The study is significant as it will be of benefit to famers, government and to fellow researchers. Farmers will benefit from the study as the study will highlight the level of maize (Zea may) infestation in Awka metropolis and the kind of parasitic nematode responsible for plant damage. This fore knowledge will enable farmer effectively sort for ways to prevent or manage the infestation of maize plant from plant parasitic nematode. Government will benefit from the study as the study will enable them see the need to make provisions for the control of plant parasitic nematode. While researcher will on the hand, benefit as the findings of this study will serve as a source of reference material for them on other related studies.