Search Filter
- Publications
- Abstract of Theses and Dissertations
- Database
- Allelopathic Effects of Chromolaena odrata (L.) R.M King and H...
Allelopathic Effects of Chromolaena odrata (L.) R.M King and H. Robinson
Thesis Abstract:
The study was conducted to determine the characteristics of Chromlaema odorata vegetarian and to investigare its allelopathic potential.
Field observation in the grassland communities of Carrangalan and San Jose, Nueva Ecija, revealed that Chromolaena odorata characteristically grew closely and densely together, forming an impenetrable thicket to exclusion of the most other species. Seedlings herbs and grasses which abound in the adjacent fields were absent under the canopy of its stand. No differences were detected between soil nitrogen and phosphorus levels inside and outside of Chromolaena stand. Light intensity under the canopy was, however, only 2.7% of that above.
Investigation into the allelopathic potential of Chromolaena showed that the species elaborated toxic compounds wich were discharged from the plant into the environment by volatization from green leaves and leaching from old brown leaf surface. Inhibitors elaborated by Chromoleana were quite specific in their actions: they retarded the germinations of certain species but stimulated the growth of some others.
Steam distillation fractionated the inhibitors in Chromolaena leaf extract into two types: the nonvolatile ones which remained in the residual fraction.