The environmental pressure and increasing legal restrictions on the use of many synthetic pesticides, emphasises the need to develop alternative control measures that are environmentally viable and easily adaptable by local farmers, through the abundant flora diversities that exist in the country. WHO estimates that nearly 200,000 people are killed worldwide every year as a direct result of pesticide poisoning. Hence the usage of underutilised weed plants such as Mexican sunflower that possess high pesticidal and soil ameliorating property needs further exploration.

Mexican sunflower

   Tithonia diversifolia is a species of flowering plant that grows up to a height of 2–3 mtrs with large yellow flowers in the Asteraceae family that is commonly known as the tree marigold or Mexican sunflower. The leaves of the plant alternate in sides they grow on, hence the name ‘diversifolia’. The weed is native to....