Studies on the Population Structure of the Tree Locust, Anacridium melanorhodon melanorhodon at Ennohoud Locality, West Kordofan State, Sudan

Abstract

During the seasons 2012/2013 and 2013/2014 at Ennohoud Locality, West Kordofan State, this study was conducted and dealt with the structure of the tree locust, Anacridium melanorhodon melanorhodon (Orthoptera: Acrididae) the most harsh insect pest of Acacia senegal, the main source of Gum Arabic production. Three sites, 10,000 M² each, dominated with natural stands of A. senegal were randomly chosen at Abumariga Wad Doomi village in the vicinity of Ennohoud town. Each site was checked once every five days starting from the beginning of May to the end of October, and at ten days intervals from the beginning of November to the end of April throughout the study course. The population structure was achieved by determining the ratio of each of the different stages and was taken from 100 nymphs or locusts randomly and then the ratio of each stage registered. Data were statistically analysed using IBM-SPSS (version 20) software package. Descriptive and inferential statistics were followed for data manipulation. Results of the study revealed that six nymphal instars were detected during the tree locust development with the 1st, 2nd and 3rd nymphs dominating the population in August-Sept. and the later instars nymphs, 4th, 5th and the 6th were noticed during September and October. In September most of the stages were observed. Fledgling was occurred in October, while th