EFFICACY OF THUNDER OD 145 AND OBERON SC 240 COMBINATION IN THE CONTROL OF WHITEFLIES IN TOMATOES NAME: MWANGANGI ANNAH BAHATI ADM NO: A22/1778/2010

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1 EFFICACY OF THUNDER OD 145 AND OBERON SC 240 COMBINATION IN THE CONTROL OF WHITEFLIES IN TOMATOES NAME: MWANGANGI ANNAH BAHATI ADM NO: A22/1778/2010 SUPERVISOR: DR. FAITH TOROITICH

2 INTRODUCTION The tomato is, after the potato, the most consumed vegetable in the world, either fresh or after processing. Tomato production rose from 48 million tons in 1978 to 74 million in 1992, 89 million in 1998 and reached 124 million tons in (Dominique Blancard, 2012) Tomatoes are popular vegetables extensively grown in Kenya for the fresh market. They are nutritious sources of vitamin A and C. Tomato cultivation is an important source of income for lowincome households.

3 PROBLEM STATEMENT Tomato crop is susceptible to many pests and diseases. However, whiteflies have posed a major threat to farmers. Various strategies have been adopted to control the whiteflies but its still a threat with farmers complaining of inefficiency of most of the available pesticides to control these pests. JUSTIFICATION Whiteflies are widely distributed in tomato growing areas in Kenya and there is a need for development of a strategy that could control them. The combination of Thunder OD 145 (Beta-cyfluthrin 45g/l+Imidacloprid 100g/l ) an insecticide and Oberon SC 240 (Spiromesifen 240g/l) an acaricide could be an appropriate method of controlling the whiteflies. HYPOTHESIS The combination of Thunder OD 145 and Oberon SC 240 at an appropriate level of concentration will contribute to an effective management and reduce the effect of whiteflies on tomatoes.

4 OBJECTIVES OF THE STUDY General Objective To contribute to an effective strategy of managing whiteflies to increase production of quality tomatoes. Specific Objective To test the effectiveness of Thunder OD 145(Betacyfluthrin 45g/l+Imidacloprid 100g/l )and Oberon SC 240 (Spiromesifen 240g/l)combination in the management of whiteflies.

5 MATERIALS AND METHODS Site; at the College of Agriculture and Veterinary Services (Upper Kabete) field station Experimental layout (RCBD) Crop Establishment Tomatoes (cal J variety), early maturity period. Plant type is determinate, no staking. Agronomic practices and harvesting. Experimental plot was 15.2m by 10.6m. The plot dimension was 2.4m by 2.7m. Inter-row spacing was 0.9m and inter plant spacing was 0.6m. 6 treatments were applied each replicated 3 times.

6 T1-Thunder OD ml/5l of water, T2- Oberon SC 2.5ml/5l, T3-Thunder+ ml/5l, T4 -Thunder+ Oberon@2.0ml/5l T5-Thunder T6 -Control experiment. The treatments were applied weekly using a 5l hand sprayer and data was collected prior to treatment application. Data was collected on whitefly nymphs Data collection done randomly, 5plants/plot, 3 leaflets/plant(upper, middle, lower). Data analysis (Genstat)- Done using the General analysis of variance and separated means using the Anova.

7 RESULTS EFFECT OF TREATMENTS ON WHITEFLY NYMPS OVER TIME Treatments Pre- Treatment week 1 week 2 week 3 week 4 week 5 means Thunder@2.5mls e Oberon@2.5mls d Thunder+ Oberon@2.5mls a Thunder+ Oberon@2.0mls b Thunder+ Oberon@1.5mls c Control f Lsd Cv 2.2

8 mean number of whiteflies per 3leaves per plant 100 LINE GRAPH OF NYMPH POPULATION OVER TIME control 0 pretreatment wk1 wk2 wk3 wk4 wk5-20 Time in weeks

9 Means of whitefly nymps per plant EFFECT OF TREATMENTS ON MEANS OF YIELDS OVER TIME Treatments

10 DISCUSSION The combination of Thunder OD and Oberon SC effectively controlled whiteflies. This is due to the anti feeding effect induced by Thunder and its duo-target action of its active ingredients, Betacyfluthrin (Contact) and Imidacloprid ( Systemic). Oberon SC is highly effective on eggs and nymphs, has high activity on pupae and affects adults by reducing on the number of adults layed. The results obtained concur with those obtained by A. Suganthi et al 2006 on Bioefficacy of spiromesifen on Bemisia tabaci and Ngari, B. M et al,2007 on whitefly control in KARI Mwea.

11 CONCLUSION The combination of Thunder OD 145 and Oberon SC 240 at a 2.5 mls/5l of water was the most effective in the control of whiteflies in tomatoes. RECOMMENDATION I would recommend the use of the combination of Thunder and Oberon@2.5mls/5l in economic production. Rate of 2.5mls/5l will effectively control whiteflies at the same time giving high yields.

12 REFERENCES A. Suganthi, K. Ramaraju, S. Kuttalam and S.Chandrasekaran, Bioefficacy of Spiromesifen (Oberon ) 240 SC against Bemisia tabaci and Trialeurodes vaporariorum and Determination of Residues. Journal of Entomology, 3: Dominique Blancard, 2012, Tomato diseases: Identification, Biology and Control.