(39-48) Mohamed et al (2016) Investigations on the Biology and Ecology of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) at New Halfa Scheme, Eastern Sudan
Hussien A. Mohamed1*, El Sayed E. Mohamed2 and Abdalla A. Satti3
1Faculty of Agriculture, University of Kassala,
2Faculty of Agriculture, University of Khartoum,
3Environment, Natural Resources & Desertification Research Institute, National Centre for Research, Khartoum
*Corresponding author, E-mail: apbc.92@gmail.com
Accepted: 1st December 2016, Published: 31st December 2016
Abstract
The African bollworm (Helicoverpa armigera) is known as a major pest of cotton and other crops in Sudan. The current study aimed to investigate some biological and ecological aspects of this pest, during 2007- 2010, including; surveys of host plants, as well as laboratory and field experiments on lifecycle, seasonal incidence and host preference. The mean durations of pre-imaginal stages, as followed on tomato (cv. Peto 86) fruits under laboratory conditions (mean, 26.2°C and 34% R.H.), were; 2.70±0.15, 16.50±0.18 and 10.80±0.20 days, for egg incubation, larval and pupal stages, respectively. The average period from egg to adult emergence was 30.00±0.53 days. Adult lifespan was 11.00±0.56 days for female and 9.90±0.53 days for male. Fecundity was 620.60±35.70 eggs as an average per female, during an oviposition period of 6.90±0.23 days. Survey results revealed eight plant species as major hosts for the pest, with pigeon pea and lablab bean displaying the highest incidence of infestation, whereas the wild plant “Tabar” Ipomoea cordofana sustained the lowest. Moreover, comparative studies among three tomato cultivars showed insignificant relatively high preference of the pest to Castle rock and Peto 86 compared to Strain B, as with respect to insect count and damaged fruits. It is concluded that H. armigera is an all seasons’ pest in New Halfa, with high fecundity and multiplication levels on different host plants. Such hosts which are grown at variable times of the year help to enhance early buildup of the pest on cultivated crops especially in winter.
Keywords: African bollworm, Lycopersicon esculentum, lifecycle duration, host plants, seasonality.
