XXVl International Symposium on Crop Protection

Abstract

The millet head worm, the larval stage of the Noctuidae moth Raghuva albipunctella has become the most serious pest of millet in the Sudan. The adults emerge seven weeks after the first effective rainstorm of over 30 mm, which coincides with the heading of most millet varieties. The female lays eggs on newly emerged millet heads. Larvae enter the head and mine within the head, eating the bases of the flowers pushing up the severed florets in a characteristic spiral trace. Long‐maturing varieties and delayed planting are both effective in reducing the incidence of infestation but are impractical in the environmental conditions in Western Sudan. Varietal tolerance has been identified and should be used as one aspect of control. Synthetic pyrethroids reduce incidence but do not significantly increase yield. The use of triple superphosphate fertilizer increases yield and reduces the incidence of the head worm by reducing the time interval from planting to heading and resulting in the emergence of the main heads prior to the emergence of the pest.     

Twenty-ninth International Crop Protection Symposium,Gent, Belgium,May 1977

Abstract

A new simple mass rearing technique for Heliothis armigera is described. Based on environmental and spatial considerations, the technique employs a semi‐artifical diet in conjunction with group rearing at all stages of development and obviates the need for individual handling of eggs, larvae and adults.     

The First Caribbean Plant Protection Symposium 1974

Abstract

A graticule for the determination of spray droplet size is described.