Abstract
We have developed a new bioassay named Dish Pack Method for analyzing volatile allelochemicals. In this method, leaves of plants were put into one of the holes in a 6-well-multi-dish. Each side of the multi-dish was sealed and put in incubator. The growth of test plants was measured after 4 days. It is possible to analyze the internal volatile gas collected from the hole with gas-tight-syringe through the septum set up on the holes. Volatile compounds from these test plants were analyzed by GC-MS. From Leguminosae and Papaveraceae plants, carbonyl compounds (trans-2-hexenal and cis-3-hexenol) were identified as major compounds. From Compositaea and Labitaea, monoterpenoids (α-Pinene, Limonene, Myrcene et al.) were mainly identified. Spider flower (Cleome spinosa) contained strong volatile allelochemical. Methyl isothiocyanate (MITC) was identified in Spider flower by GC-MS. MITC was released from injured leaves. Volatile allelopathic activity of Cleome cultivars were also evaluated.
