Investigations were carried out to establish the phagostimulatory effects of cheaply available materials (bag sugar, sucrose, molasses) on Chilo partellus larvae. Sugar and analytical grade sucrose (1% w/v solutions) were the best phagostimulants tested. Molasses was the least effective but a 10% w/v solution induced a significant feeding response. These stimulants, in combination with a Bacillus thuringiensis treatment, were tested to determine their effects on increasing the efficacy of the pathogen against this pest species. Larval mortality levels were significantly higher in the presence of a feeding stimulant than when B. thuringiensis alone was administered; inclusion of such adjuvants in a B. thuringiensis preparation could significantly enhance the field efficacy of the pathogen against C. partellus.
