Unlike other members of the genus, rainbow eucalyptus halls from the Philippine Islands; specifically, the Island of Mindanao, which Is why the tree Is also referred to as a Mindanao gum. According to the study of Bughio, Mangrlo, Abro, Jahangir and Bux, it has been found that Eucalyptus species release volatile compounds such as benzoic, cinnamic and phenolic acids which inhibit growth of crops and weeds growing near it. Phenolic acids and volatile oils released from the eaves, bark, and roots of certain Eucalyptus spp. ave deleterious effects on other plant species.
In the study of Bughio et al. , using the eucalyptus camaldunlensis as allelopathy agent against Acasia nilotica, The Eucalyptus leaf litter and leaf litter extract also caused significant reduction in seedling vigour index of Acacia nilotica. Based on the results of their study it is concluded that allelopathy is a concentration- dependent phenomenon, as the concentration of the E. camaldulensls treatments increases, Its effect Increases. The leaf litter and leaf litter extract affected all the arameters as compared to the control.
Based on the study of Anwar, Eucalyptus has been known to be able to excrete a substance harmful called allelopathy, to other vegetation. To encourage the establishment of timber estate, it is necessary to examine the effects of allelopathy on other plants, whenever mixed plantation is carried out. Three kind of plant portion (fresh leaf, leaf litter and root) from two Eucalyptus species (Eucalyptus alba and E. deglupta) which are suspected to have allelopathy and five extract concentrations (0%, 5%, 10%, 15% and 20%) were used as reatment for the growth of Shorea palembanica seedlings.
The experiment result showed that Eucalyptus was allelopathic against Shorea seedlings. Of the three plant portions, the fresh leaf had the most potential to obstruct the growth of Shorea seedlings. There was a tendency that the more Eucalyptus extract concentration Is given, the less the growth and the quality of Shorea seedlings become. The relation of growth (Y In cm) and quality (Y) of Shorea seedlings and extract concentration (X In was described by equations. Another native species in the Philippines is the Alstonia scholaris, which is locally nown as Dita.
According to Pratap, Chakraborthy, and Mogha, the principal constituents of the said plant were reported to be linalool (35. 7%), cis and trans linalool oxides, alpha-terpineol and terpinen-4-ol(5). Based on the study conducted by Banerjee and Pandey, it was recorded that maximum inhibition in seed germination as well as mortality in seedlings was found with the leaf extracts of A. scholar’s, showing that It possesses significant allelopathlc effect. Trema orientalis, a fast-growing evergreen shrub Is also native to the Philippines.
It has good adaptation to the environment, and known to possess triterpenolds, sterols, fatty acids and flavonoid glycosides. Allelopathy: A Concentration-Dependent Phenomenon By kmct01 allelochemicals. One of them is the Eucalyptus deglupta, which is unique among eucalyptus. Unlike other members of the genus, rainbow eucalyptus hails from the Philippine Islands; specifically, the island of Mindanao, which is why the tree is also referred to as a Mindanao gum. According to the study of Bughio, Mangrio, Abro, dependent phenomenon, as the concentration of the E. amaldulensis treatments ncreases, its effect increases.
The leaf litter and leaf litter extract affected all the seedlings. There was a tendency that the more Eucalyptus extract concentration is of growth (Y in cm) and quality (Y) of Shorea seedlings and extract concentration (X in %) was described by equations. Another native species in the Philippines is the Alstonia scholar’s, which is locally scholaris, showing that it possesses significant allelopathic effect. Trema orientalis, a fast-growing evergreen shrub is also native to the Philippines.