Determination of rooting-inhibitors in Eucalyptus dunnii cuttings

Rooting-inhibitors of Eucalyptus dunnii cuttings were studied with E.dunnii rooting hard and E.urophylla×E.Grandis clone (U9) rooting easily from biological effect, acidity and chemical assay, etc. Results showed that, compared with U9, the biological effect of E.dunnii cuttings extract was stronger, while the acidity and the main acid substance were similar, and the difference for chemical assay of phenolic compounds was significant. The content of phenolic compounds in E.dunnii extract was evidently greater by determination. Both phenolic compound that had inhibitive effect and phenolic compound that had promoting effect existed in the U9 extract, while there was only inhibitive monohydric phenolic in E.dunnii cuttings by GC-MS analysis. This preliminary indicated that the inhibition effect of acid substance on E.dunnii cuttings rooting was not significant, while the monohydric phenolic of phenolic compounds probably had certain inhibition effect on E.dunnii cuttings rooting.