Abundance and diversity of safflower insect pests and their natural enemies

A study was carried out in a farmer’s field in Molepolole, Botswana to investigate diversity and abundance of different insect pests in five safflower genotypes. Thirteen insect species belonging to eight arthropod orders were observed during the study. Insect pests attacked all safflower genotypes, but population fluctuations were attributed to days after plant emergence. “Gila” recorded the highest number of individual species while “Kenya’’ recorded the lowest. There was a notable difference in abundance and diversity of insects among plant growth stages. Flowering stage recorded the maximum number of individual species. The insect pest Helicoverpa armigera was of major concern causing considerable damage to safflower. Cheilomenes lunata, Apies mellifera, spider and Formicidae sp.1 were recorded as beneficial insects. Leaves and capitula were the most affected parts of safflower. Relative humidity and temperature significantly (P < 0.05) influenced insect pest population; an increase in temperature increased insect pest population while an increase in relative humidity decreased insect pest population. Keywords: Botswana, Capitula, genotype, safflower, species richness, species evenness