Asian Research Journal of Agriculture 8(3): 1-11, 2018; Article no.ARJA.40496 ISSN: 2456-561X Development of Bait for the Management of Coffee Bean Weevil, Araecerus fasciculatus in Stored Cocoa A. Eduku1, B. K. Maalekuu1, P. D. Kaledzi1 and P. K. Tandoh1* 1Department of Horticulture, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana. Authors’ contributions This work was carried out in collaboration between all authors. Author AE designed the study, performed the statistical analysis, wrote the protocol, and wrote the first draft of the manuscript. Authors BKM and PDK managed the analyses of the study. Author PKT managed the literature searches. All authors read and approved the final manuscript. Article Information DOI: 10.9734/ARJA/2018/40496 Editor(s): (1) Rusu Teodor, Department of Technical and Soil Sciences,University of Agricultural Sciences and Veterinary Medicine Cluj- Napoca, Romania. Reviewers: (1) Hanife Genc, Canakkale Onsekiz Mart University, Turkey. (2) R. P. Soundararajan, Tamil Nadu Agricultural University, Tamil Nadu, India. Complete Peer review History: http://www.sciencedomain.org/review-history/24007 Received 14th January 2018 Accepted 31st March 2018 Original Research Article th Published 7 April 2018 ABSTRACT An experiment was conducted at the Laboratory of the Horticulture Department of Kwame Nkrumah University of Science and Technology between January and March, 2012 within temperature and humidity ranges of 18–32°C and 63–85%, respectively. The purpose of the investigation was to develop an effective insecticidal cassava bait to control insect pests of cocoa in storage using Araecerus fasciculatus (De Geer) as model species. A completely randomized design was used for the study. It was conducted in a five-roomed glass cage of 60 cm x 60 cm x 200 cm with the backside made of a net to improve aeration in the cage. It was observed that A. fasciculatus preferred sun-dried chips to fresh chips, fermented dough, flour and cocoa beans and that soaking of sun-dried chips in brown sugar solution of 500 g per litre of water further enhanced the preference. Deltamost emerged superior to Fastrack and Confidor insecticides by registering 4–6 minutes of lethal time, 21–30 days persistence and attract-and-kill potential of 76.7 – 86.7% of infested bagged cocoa beans. However, cassava bait at 25% of Deltamost insecticide was at equal strength (p < 0.05) with the 50 and 75% of the label dosage and should be the obvious choice for the insecticidal cassava bait preparation. _____________________________________________________________________________________________________ *Corresponding author: E-mail: [email protected]; Eduku et al.; ARJA, 8(3): 1-11, 2018; Article no.ARJA.40496 Keywords: Semiochemicals; infestation; insecticidal; cage; persistence. 1. INTRODUCTION its depleting effect on the ozone layer [11]. On the other hand, the EPA proposed a ban or Cocoa (Theobroma cacao L.) is a cash crop of restrictive use of phosphine because it is highly huge economic significance in the world and the toxic and insects rapidly build resistance to it key raw material for chocolate manufacturing [1, [12]. Environmental concerns, chemical residues, 2]. It forms the major agricultural export insect resistance and worker safety issues have commodity for several producing countries in increased interest in alternative, safer, selective West and Central Africa, such as Cote d'Ivoire, and ecologically acceptable toxophores and Ghana, Nigeria and Cameroon [3]. Côte d’Ivoire, novel methods of application including the use of Ghana and Indonesia are the leading producers insecticidal baits [13]. Though dry cassava chips of cocoa in the world in terms of land area under have been found to be preferred by a primary production and production volumes. Ghana plays pest of stored cocoa, Araecerus fasciculatus De a major role as the second largest cocoa Geer Boateng and Chijindu, 2008, much work producing country with production suddenly has not been done in the use of baits to control rising to about 540 000 metric tonnes during the insect pests of cocoa beans as well as 2003/2004 crop year and reaching 720, 000 using cassava as an attractant in insecticidal metric tonnes which constituted 20.7% of world bait formulation [14]. The purpose of production as at the end of 2009. Its production this investigation, therefore, was to was reported to have reached 1.0 million metric develop an effective insecticidal cassava bait to tonnes by end of 2011 according to Ghana control insect pests of cocoa in storage using Cocoa Board [4]. In Ghana, cocoa has been A. fasciculatus as model species with the labelled ‘the golden pod’ owing to the pivotal role following specific objectives: 1. determine the it plays in the nation’s economy. It is cultivated cassava preparation that is most preferred on about 1.5 million hectares of land by some by A. fasciculatus; 2. determine the effect of 800,000 families in six out of the ten regions. It is brown sugar on the preference of Araecerus to cultivated almost exclusively by small-holder cassava; 3. identify the most effective farmers with average farm sizes of about 4.0 ha chemical for the cassava bait preparation and and mean production yield of 246.4 kg/ha [5,6]. 4.determine the efficacy of insecticidal cassava Ghana’s cocoa sector employs millions of people bait in controlling Araecerus infestation of both formally and informally because it is the bagged cocoa beans under cage. predominant farming activity. The cocoa sector alone contributed up to 22.4 percent of the total 2. MATERIALS AND METHODS foreign exchange earnings of Ghana during the 2002 season. According to Dwinger (2010), 2.1 Experimental Site cocoa contributed nine (9) percent of Ghana’s gross domestic product (GDP) in 2008 [7].This The experiment was conducted at the laboratory contributed sixty-three (63) percent of the entire of the Horticulture Department of the Kwame foreign export earnings accrued from the Nkrumah University of Science and Technology agricultural sector. According to Osei (2007), a between January and March, 2012. The good quality cocoa is one devoid of insect experiment was performed within temperature infestation and high levels of chemical residues and humidity ranges of 18-32°C and 63-85% in the produce [8]. The sale of cocoa that has respectively. any of these attributes may suffer outright rejection by the buyer or may be subjected to 2.2 Experimental Cage and Study Design high arbitration cost to the country. Bateman (2010) reported that insect infestation and A transparent glass cage of 60 cm x 60 cm x 200 chemical residues in cocoa beans are major cm was constructed with the backside of the challenges confronting the cocoa industry in cage made of a net to improve aeration. The top Ghana [9] and according to Jonfia-Essien et al. had four breaks at 40 cm interval where partition [10], fumigating cocoa beans with methyl glasses inserted created five equal cabins. Each bromide and phosphine is the current method of cabin had a sliding door on the front side and the controlling insect pests of stored cocoa. The use base was made of a transparent glass. The of methyl bromide however, was banned in various set up were laid out using a completely developed countries in 2005 and it was to take randomized design. effect in developing countries in 2015 because of 2 Eduku et al.; ARJA, 8(3): 1-11, 2018; Article no.ARJA.40496 2.3 Culturing of Experimental Insects and the cocoa used were counted. This was repeated three times by randomizing the Culture of Araecerus fasciculatus (De Geer) was arrangement of the treatments in the cage and raised from a field strain of parent stock obtained the number of A. fasciculatus attracted to each from Ashanti Bekwai. An insect haven was treatment 24 hours after introduction into the created in a garden behind the Quality Control cage was recorded. (COCOBOD) office by drying cassava chips on a raised platform and any A. fasciculatus that was 2.4.2 Experiment to determine the attracted was captured with a pooter. The culture preference of A. fasciculatus to dry was prepared using ten Kilner jars with dry cassava chips and chips immersed in cassava chips sterilized in an oven at a brown sugar solution temperature of 60°C for 24 hours. The moisture content of the sterilized chips was reduced to 9 A solution was prepared using 500 g of brown %, measured using an Aqua Boy. The jars were sugar and one litre of water. One kilogram of dry filled with the sterilized cassava chips to three- chips was soaked in the solution and the mixture quarters full before introducing the insect. The was transferred into a black polyethylene bag insects were secured in the jars with meshed and kept for 12 hours. A comparison was made covers to provide adequate aeration in the by placing 300 g each of dry cassava chips, bottles. The jars were then placed on plastic soaked chips and cocoa as the control in the trays containing industrial oil to prevent cage and twenty day-old A. fasciculatus were contamination of the culture by other insects. The introduced. The experiment was repeated three insects were sieved off 12 days after introduction times by randomizing the arrangement of the and the contents kept for fresh insect treatments in the cage. The number of immergence. A. fasciculatus attracted to dry cassava chips, chips immersed in brown sugar solution and 2.4 Data Collected cocoa beans 24 hours after introduction into the cage were recorded. The following data were collected during the study; 2.4.3 Preparation of insecticidal cassava bait 2.4.1 Evaluation of the preference of The cassava bait was prepared using 500 g of A.