Annals of Plant Protection Sciences

Results revealed that the plant extract of Alpinia galanga caused maximum mortality (80.8%) larval mortality of Athalia proxima followed by 67.9% in C. longa, 66.3% in A. melegueta and 62.1% in Z. officinale and compared to 6.6% in control. The plant extract of Alpinia galanga differed significantly from remaining plant extracts except C. longa. The concentration of 2.0% was superior to 1.0 and 0.5%. It was also observed that the difference in the percentage kill of larvae between concentrations 1.0% and 2.0% was greater than the difference in mortality between 0.5% and 1.0% in all the three periods. It was also seen that 2.0% induced 83.5% larval mortality with in 6 hrs of exposure but in another 18 hrs larval mortality increased only by 7.58%.