Allelopathic Effects of Tectona Grandis And Leucaena Leucocephala Aqueous Extracts on Germination and Growth of Zea Mays And Vigna Unguiculata

2017

English

Aims: This study was conducted to evaluate the allelopathic potential of the leaf and bark extracts of Tectona grandisand Leucaena leucocephala on germination and growth of maize and cowpea. Study Design: Experimental study in the laboratory and field. Place and Duration of Study: Department of Integrated Science Laboratory, University of Education Winneba, Mampong-Ashanti, Ghana between March 2015 and August 2015. Methodology: Fresh leaves and bark tissues were soaked in distilled water for 24 h at 25ºC in a lighted room to give concentrations of per 100 ml of water. Bioassay was conducted to germinate seeds of maize and cowpea seeds in Petri dishes Results and Discussion: The study showed gross morphological effects of aqueous extracts of T. grandis and L. leucocephala leaves and barks on cowpea and maize. There were discolouration, lack of root hairs necrosis of root tips, seed darkening and swelling. These morphological changes could be attributed to the allelochemicals in the plant parts used. The results further revealed that leaf extracts from T. grandis at 50% and 80% concentrations inhibited the sprouting and growth of cowpea seeds. At 100% concentration of the same leaf extract there was no influence on cowpea seed sprouting compared to the control. Conclusion: It can be concluded that allelopathic characteristics of readily available T. grandis could be exploited in agriculture. Both the bark and leaf aqueous extracts of T. grandis have the allelopathic potential for use in agriculture. This could be done with obnoxious weeds specificity.