A native parasitic plant is effective in controlling the growth of an exotic plant-killing weed rampant in the countryside and on abandoned farmland in Hong Kong, a Chinese University study has found.
Trials have been carried out on Centre Island in Tolo Harbour since last August, and the results have been encouraging, showing growth of the killer weed, Mikania micrantha, had been halted, researchers have reported.
They entwined the dodder, or Cuscuta campestris, around the Mikania plants, depriving them of nutrients. As the Mikania withered, the dodder would also die.
The trials were the first of their kind in Hong Kong. Scientists around the world have been working to eliminate the invasive species using everything from natural controls to herbicides. No method delivered satisfactory results.
Nicknamed 'mile a minute' and considered one of the top 100 invasive species, M. micrantha originated from South America but has now spread across the world, threatening local ecosystems.
The plants are capable of generating 200,000 seeds from a growth measuring 1 square metre, while their stems can increase in length by 1,000 times in a year. It covers trees and kills by blocking the sunlight needed for photosynthesis.
Paul But Pui-hay, of the university's department of biology, who was in charge of the trials, said that while the tests confirmed the dodder's effectiveness in controlling Mikania's growth, it would not kill them completely.