Parasitic Nematode Associated With Maize Damage in Awka Metropolis Faculty of Agriculture
Chapter One
Objectives of the study
The broad objective of this study is to
- The prevalence of maize infestation by parasitic nematode in Awka
- The type of parasitic nematode responsible for maize damage in Awka.
CHAPTER TWO
Literature Review
Maize is the most important cereal crop produced in Nigeria. Its importance has grown from being a food crop to a cash crop with its production now being market driven (Manyong et al., 1996). Furthermore, productivity of the crop has increased from 1.2 tonnes/ha in the early 1980s to its present level of 1.7 tonnes/ha due to several interventions by the government (Alene et al., 2009). Increase in population and improvement in general income levels in developing countries will increase demand for meat (especially poultry) and other animal products hence, there will be an increase in the quantity of grains needed for feeds.
In Nigeria, maize is the main carbohydrate food source for both rural and urban families. Many plant pathogens and pests, including plant parasitic nematodes cause considerable loss during crop development and aggravate plant damage under moisture and other stress conditions (McDonald and Nicol, 2012). Information on the importance of plant parasitic nematodes used to be very limited, but a significant number of publication on maize-nematode associations have appeared over the past decade. This implies increasing awareness of the importance of nematode damage to this very important food and fodder crop.
Previously, the maize crop was commonly regarded as a non-host to several nematode species (Idowu and Fawole, 2010; Toida et al., 2009; Rodriguez-Kabana, 2011), probably because yield losses may go unnoticed as a result of natures of it root-systems (Koenning et al., 2011) or lack of typical symptoms (Asmus et al., 2013). The prominence of maize in the global and many local economy as a staple food to millions emphasizes the fact that the impact of nematode parasitism on this crop should not be underestimated. The extensive use of maize in rotation systems further necessitates a profound knowledge of the crop’s host status to economically important nematode species.
Over 60 nematode species have been found associated with maize in different parts of the world (McDonald and Nicol, 2012). Most of them have been recorded from roots and soil around maize roots with information on the biology or pathogenicity of many of these species not readily available. The most important groups of plant parasitic nematodes demonstrated to be important limiting factors in maize production from all over the world are; the root knot nematodes, Meloidogyne species; the root lesion nematodes, Pratylenchus species; and the cyst nematodes,
According to McDonald and Nicol,(2012). Heterodera species root knot nematodes which comprising of more than 50 species are considered economically important on maize. Some species have a worldwide distribution and have wide host ranges, while others are limited in distribution and are more hosts specific. Several races with differential host ranges occur within species (Sasser and Triantaphyllou, 2014; Kleynhans, 2012). It is important, therefore, to know the status and distribution of root knot nematodes on an important crop such as maize. Meloidogyne incognita and Javanese root knot, Meloidogyne javanica had been detected damaging maize in almost all maize-growing areas.
African root knot, Meloidogyne africana and Peanut root knot, Meloidogyne arenaria have been recorded on maize in Nigeria (Krishnamurthy and Elias, 2010) and four races of M. incognita and race 2 of M. arenaria sometimes reproduce well on maize but some cultivars exhibit specificity to a specific race (Lopez, 2011; Davis and Timper, (2012). Although root knot nematodes occur frequently in maize fields, information on economic losses is lacking. However, indirect observations when nematicides are applied in root knot infected soils suggest that these nematodes are economically important in maize (Henshaw, 2011). In Nigeria greater root knot damage occurred when maize was sown after sugar cane(Hutton, 2009). Failure to demonstrate yield reduction due to nematode parasitism in maize was explained by Dickson and McSorley (2010) as being a result of extensive root growth in this crop after the seedling stage. This is due to high fertilization and watering levels applied to this crop and it obscures measurable injury levels. Koenning et al. (2009) add a lack of adequate control measures on maize as a reason for ignorance of nematode damage on the maize. Goswani and Raychaudhuri (2011) studied the interaction between mosaic virus and M. incognita in pot trials. They found that the mosaic symptoms appeared earlier and nematode reproduction was greater when both pathogens were together than when alone. It remains an important aspect to be alert to root knot nematode infestation of maize particularly in low input production conditions.
CHAPTER THREE
MATERIALS AND METHODS
The method adopted used in carrying out the study are presented in this chapter.
Material Used
The full plant, root knot and maize cob was gotten from Anambra Agricultural Ministry of Agriculture.
Other materials used are as follows;
Soil probe, potting bag, Root knot of maize plant, infested and healthy maize cob, Microscope,Forceps , Camera.and Baermann funnel , petri dish , distilled water,conical flask, 20-mesh sieve( 8833µm aperture), 200-mesh sieve (74 µm aperture),325 mesh sieve(43µm aperture ) , two plastice bowls, 250ml beaker, coarse siceve(1cm aperture) and coarse spray was bottle
CHAPTER FOUR
RESULTS
This chapter presents the result finding from the study. The results of the study are presented in tables, photographic pictures and in graphs.
