Boma Trials on the Use of the Gregarious-Adult Pheromone Phenylacetonitrile of the Desert Locust Schistocerca gregaria (Forskål, 1775) and Metarhiziumacridum in the Management of Nymphs

Abstract

The trials were conducted within plastic Bomas (10 x10
meters each) in a farm at Sallom (19 38 55 N X 37 15 37 E) 45 kilometers
South West of Port Sudan, Sudan. Approximately 1000 fourth instar
nymphs of the Desert Locust Schistocerca gregaria (Forskål, 1775) were
used per replica in each test. Each test was replicated three times. The
treatments included different dosages of Metarhizium acridum alone or
incorporated with the Desert Locust gregarious adult pheromone
Phenylacetonitrile (PAN). The results indicated that the cumulative
mortality rate in day 15 at the end of the tests was 0.994±0.010 with
Metarhizium 50 g/ ha. (recommended dose). The rates were 0.991±0.001
and0.967±0.003 with fractional doses of Metarhizium, 25g/ha +PAN and
12g/ha + PAN respectively. When PAN was used alone, the cumulative
mortality at day 15 was 0.739 ± 0.017. The same trend in the mortality
rate was also evident when the control efficiency was examined. The
efficiency in day 15 was 99.32 ± 0.001 with Metarhizium 50 g/ ha.
(recommended dose). The rates were 98.75 ±0.056, 96.33±0.30 and
72.78±0.45 with fractional doses of Metarhizium 25g/ha +PAN, 12g/ha
+PAN and 6g/ ha +PAN respectively. Control efficiency was 71.82±1.82
and 3.70±1.86 with PAN alone and Diesel respectively. Examination of