Sugarcane Yield Loss Due to Sugarcane Stem Borer Grub, Dorysthenes buqueti Guerin

Abstract

Yield losses caused by the stem borer grub, Dorysthenes buqueti, wee studied in 1984/85 and 1985/86 in chon Buri province for the sugarcane variety F 156. High and low infestations were compared in 1984/85, and in 1985/86 chlodane treated (0.6 kg z.i./rai) and untreated plant cane were compared; the latter study was extended into the first ratoon crop.
In the 1984/85 study, mean grub numbers in teh high and low infestations were 3.3 and 0.8 per meter row; the effect of the high infestation was to reduce cane and sugar yields by 43.3 and 45.9 percent, respectively. In the chlordane treatment study in 1985/86 relative mean grub numbers in the plant cane were 1.4 and 0 per meter row for the untreated and treated areas, respectively; the untreated plots gave reduced cane and sugar yields of 13.0 and 10.8 percent, respectively. For the first ratoon cane, mean grub number in teh untreated and treated areas were 4.5 and 0.5 per meter row; cane and sugar yields were reduced by 53.7 and 56.8 percent respectively, in the untreated areas.