Toxicity of pulai plant extract (Alstonia scholaris) as a natural pesticide against pest Spodoptera litura

The aspects of nutritional adequacy in food security have been realized by the public and industry, especially for export needs. The use of synthetic pesticides creates residues that affect the quality of agricultural products so natural pesticides are needed. Pulai plant extract (Alstonia scholaris) contains flavonoids and alkaloids that are toxic to insect pests. This study was to determine the effect of pulai extract on Spodoptera litura mortality. This study is used a completely randomized design (CRD) method with 10%, 20%, 30%, 40%, 50% of pulai extract concentration and 1 control with 5 replicates, each replication consisting of 10 larvae. Pulai leaf extraction through maceration method and S. litura used was insar II larvae, then the toxicity test was carried out by dipping cabbage into the extract solution, then observing the mortality rate of the test insects and analyzed using probit LC50 analysis. The result is the value of LC50 for 24 hours is 43.25% and 48 hours is 13.26%. Observation showed that the higher the concentration of the pulai extract, the higher the mortality rate of S. litura. So it was concluded that the extract of the pulai plant is toxic to S. litura.