1.1 Introduction
Maize (Zea mays L.) is the second most important cereal crop grown in Sierra Leone after rice, the country’s staple. The crop is cherished by Sierra Leoneans and is grown in homesteads in the uplands during the raining season and inland valley swamps in the dry season (MAFFS, 2005). It has a very high commercial value when compared with other food crops grown in the country contributing to poverty alleviation. Maize grain yields are generally low with national average of 2t/ha (USDA, 2015). The low grain yields may be attributed to inadaptable maize varieties, varietal mixtures in the hands of farmers, low reactions to insect pests and diseases and abiotic factors. The demand for maize in Sierra Leone is rising as the human and livestock population increases. This rise means developing new cultivars that will meet the growing demand of the Sierra Leone population.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
Genetic resources are the most valuable and essential basic raw material to meet the current and future needs for genetic improvement of any crop (Kaur et al., 2017). The choice of germplasm is fundamental and decisive in any plant breeding program, which is aimed at the development of open pollinated varieties or obtains pure lines for use in hybridization (Baretta et al., 2016). Open populations contain a gene pool with high value and represent important source of genetic variability that can be explored in the search for genes of tolerance and/or resistance to biotic and abiotic factors (Araújo and Nass, 2002).
Genetic variation among traits is important for breeding and in selecting desirable types (Astereki et al., 2017). Characterization studies allow pointing out the variability pattern of the most significant variables and establishing groups of accessions with similar traits. Assessment of genetic diversity, relationships, and structure within a given set of germplasm is useful in plant breeding. The genetic improvement through hybridization and selection depends upon the extent of genetic diversity between parents. Assessment of germplasm diversity by morphological descriptors still remains the only traditional and legitimate marker type accepted by the International Union for Protection of new Varieties (UPOV, 2009) (Ghixari et al., 2014). The use of morphological descriptors is unavoidable for DUS (Distinctness, Uniformity and Stability) testing and in the procedures for protection of varieties (Cupic et al., 2009).
However, there is inadequate information regarding the amount of genetic variation in maize germplasm arrays to make important consideration for effective and efficient utilization of germplasm resources in Sierra Leone. This study was therefore conducted in open-pollinated maize varieties, with broad genetic base, to characterize genotypes for desirable attributes and identify promising sources of variability, which could be exploited in breeding programmes.
1.3 Statement of Problems
Investigation reveals the problems of the Genetic and Morphological Diversity in Zea Mays:
- Insufficient information needed for Morphological Diversity in Zea Mays,
- Inadequate analysis and determination of Morphological Traits, Cluster Analysis, and Correlation of Traits in Zea Mays
1.4 Aim and Objectives of Study
The aim of the study is to examine the Genetic and Morphological Diversity in Zea Mays. In achieving this aim, the specific objectives were set out as follows:
- To determine the genetic and morphological Diversity in Zea Mays, and
- To determine the Morphological Traits, Cluster Analysis, and Correlation of Traits in Zea Mays.
1.5 Scope of Study
The scope of the study focuses on the Genetic and Morphological Diversity in Zea Mays.
1.6 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Research Material: availability of research material is a major setback to the scope of the study.
- Frequent Power Failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials.
1.7 Significance of Study
This research work will be of immense importance to the researchers, since it is a practical requirement for the award of Ordinary National Diploma (OND) in Science Technology of the Institute of Management and Technology (IMT), Enugu.
This study will be of immense benefit to other researchers who intend to know more on this study and can also be used by non-researchers to build more on their research work. This study contributes to knowledge and could serve as a guide for other study.