1.1 Introduction
The Bean Weevil, Acanthoscelides obtectus (Say) (Coleoptera: Bruchidae) is a cosmopolitan insect and a major insect pest of common beans of various species, Phaseolus spp. widely distributed in almost all continents (Hill, 1989; 2009; Paul, 2007). A. obtectus causes considerable economic losses to beans particularly under small-scale subsistence farming systems in East Africa (Mphuru, 1981; Paul, 2007). Nigeria produces more common beans than any country in East Africa as acknowledged by Hillocks et al., (2006) and Fivawo and Msolla (2011). It is reported in KDC (2009) and KDCU (2011) that more than 90% of the crop isgrown by small scale farmers under traditional production systems where on average farm sizes range from 0.5 ha to 2 ha.
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, Research hypothesis and questions, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
In rural areas crop pest management is a prominent problem as most smallholder farmers are yet to fully integrate synthetic insecticides into their insect pest management systems due to the prevailing subsistence economy and hence reliance upon traditional knowledge systems in meeting their protection needs (Warren, 1991;Mihale et al., 2009; Machocho et al., 2012). Components of IPM commonly employed to protect harvested crops from insect’s attack and damage include traditional insecticide materials and maintaining granary hygiene. It is, however, reported in NRI (2006) that traditional insecticides are not consistent and often produce poor results given the very scanty investigations done on appropriate doses and resultant effect on pests. As reported by Rutatora and Mattee (2001) and Paul (2007) pest management activities in Nigeria have rarely been supported by thoroughly controlled local studies given that most interventions have been conducted during outbreak of pests wherein data obtained elsewhere is predominantly used in the crisis.
Beans are both palatable and cheap source of protein; they also provide some complex carbohydrates, dietary fibre and folic acid (Hill, 1996; Jones, 1999). It is further noted by Jones (1999) and Paul (2007) that besides its green tender leaves; green pods, immature and/or dry seeds are also a delicacy. The common bean, Phaseolus vulgaris L. was introduced to Africa from the highlands of Central and South America more than four centuries ago (Paul, 2007; Fivawo and Msolla, 2011). It is reported in the Agricultural Compendium (1985) that in terms of nutritive value, the protein content in 100 grams of fresh broad beans and peas is 5.6 grams. Amongst the staple food crops, beans are reported to have the highest level of variation in seed characteristics, namely: size, shape and colour resulting in about 40,000 varieties yet they all give identical total calories per gram (Wortmann and Allen, 1994; Fivawo and Msolla, 2011).
In farms of controlled schemes under conditions of improved cultivation practices, the yields of P. vulgaris was estimated at 2 tones/ha (Hillocks et al., 2006). Despite the low yield under unimproved systems of production by small holder farmers in Nigeria, the crop is susceptible to bruchid stored insect pests including A. obtectus. Other serious field pests of the bean crop include, Aphids, Aphis fabea (Scop.), pod borers, Maruca testulalis Geyer, Heliothus armigera Hb. and flower beetles, Ootheca bennigseni Weise (Hill, 2009).
It was imperative therefore to investigate the potential effectiveness of all the reported traditional insecticide materials in the communities in order to filling the gap. Taylor et al., (2012) correctly assert, in order to institute technological packages in appropriate stored pest management, it is paramount to have the knowledge about the nature of the crop to be stored, the biology of the pest involved, the available traditional methods of pest control and required lengths of storage periods.
Therefore, in Nigeria where the research was carried out, the activities that was conducted is to know the Determination of Phytochemical Composition and Insecticidal Effect on the Essential Oil of Leaf and Seed of Hyptis Suaveolens on Bean Weevil.
1.3 Statement of Problem
Investigation reveals that the Essential Oil of Leaf and Seed of Hyptis Suaveolens on Bean Weevil is a prominent problem as most smallholder farmers are yet to fully integrate synthetic insecticides into their insect pest management systems due to the prevailing subsistence economy and hence reliance upon traditional knowledge systems in meeting their protection needs (Warren, 1991;Mihale et al., 2009; Machocho et al., 2012). Components of IPM commonly employed to protect harvested crops from insect’s attack and damage include traditional insecticide materials and maintaining granary hygiene. It is, however, reported in NRI (2006) that traditional insecticides are not consistent and often produce poor results given the very scanty investigations done on appropriate doses and resultant effect on pests. As reported by Rutatora and Mattee (2001) and Paul (2007) pest management activities in Nigeria have rarely been supported by thoroughly controlled local studies given that most interventions have been conducted during outbreak of pests wherein data obtained elsewhere is predominantly used in the crisis.
1.4 Aim and Objectives of Study
The aim of the study is to determine the Phytochemical Composition and Insecticidal Effect on the Essential Oil of Leaf and Seed of Hyptis Suaveolens on Bean Weevil. In achieving this aim, the following specific objectives were laid out as follows:
- To determine the Phytochemical Composition on the Essential Oil of Leaf and Seed of Hyptis Suaveolens on Bean Weevil
- To examine the effect of Insecticidal on the Essential Oil of Leaf and Seed of Hyptis Suaveolens on Bean Weevil
- To provide information of Insecticide Materials Preparation and bean weevil treatment procedures for the Experiments
1.5 Significance of Study
This study will be of immense benefit to farmers, Agricultural Engineers and 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.
1.6 Scope of Study
The study focuses on the Determination of Phytochemical Composition and Insecticidal Effect on the Essential Oil of Leaf and Seed of Hyptis Suaveolens on Bean Weevil in Nigeria
1.7 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, literature or information and in the process of data collection (internet).
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