Evaluation Of The Interaction Between Beauveria Bassiana And An Aphicide For The Management Of The Tobacco Aphid Myzus Persicae Nicotianae

ABSTRACT

Aphids (Myzus persicae nicotianae) cause damage by sucking sap from the plants leading to

distortion and wilting of the foliage, and eventually reducing economic yields. In order to

minimise losses to viral diseases, it is important to use insecticides in association with fungi to

control insect pests in an environmental and ecological friendly way without contaminating the

environment. A study was carried out from October, 2013 at Kutsaga Research Station in the

laboratory to evaluate the efficacy of Beauveria bassiana (contact insecticide)and imidacloprid

(systemic insecticide) 200 SL for the control of tobacco aphid, Myzus persicae nicotianae. Three

doses of 200 SL Imidacloprid (Imida) namely: Imida low rate 0.55 ml per 500ml water (LR);

Imida medium rate 1.1 ml per 500ml water (MR) and Imida high rate (2.2 ml per 500ml water

(HR) were mixed with Broadband® Beauveria bassiana (B. Bass) at three different rates

namely: B. bass 4 x 103 (LR); B. bass.4 x 104 (MR) or B. bass 4 x 105 (HR) to evaluate the most

effective application combination rate of Beauveria bassiana and imidacloprid for the control of

the tobacco aphid. Treatments were: water (control); Imida MR; B. bass MR; B. bass LR + Imida

LR; B. bass LR + Imida MR; B. bass LR + Imida HR; B. bass MR + Imida LR; B. Bass MR +

Imida MR; B. Bass MR + Imida HR; B. Bass HR + Imida LR; B. Bass HR + Imida MR and B.

Bass HR + Imida HR. Inoculation of aphids was done and data collected from day 1 to day 7

after inoculation. Mortality of aphids was recorded at 8 o’clock in the morning cumulatively as a

percentage of the initial number infested (10 per petri dish). Results showed that there were

significantly high p