Allelopathic Potentialities of Gliricidia sepium and Acacia auriculiformis on the Germination and Seedling Vigour of Maize (Zea mays L.)

Decline in crop yield in cropping and agroforestry system in recent years has been attributed to allelopathic effects. Plants may favourably or adversely affect other plants through allelochemicals, which may be released directly or indirectly from live or dead plants. The objective of this study was to examine and quantify the nature of interference of leaf leachates of Gliricidia sepium and Acacia auriculiformis on seed germination and seedling vigour of maize and to identify morphological trait for allelopathic interference assessment of maize seedlings. Leaf leachates of both Gliricidia and Acacia significantly decreased germination percentage and increased mean germination time (P<0.05) and (P<0.01) of maize seeds particularly at leachate concentrations of 6 and 12% respectively. Similarly, all the seedling growth parameters including seedling vigour index (SVI) decreased significantly (P<0.05) and (P<0.01) with increasing level of leachate concentration compared with control. It was apparent that Gliricidia sepium perform the more inhibitory effect than Acacia auriculiformis. Shoot length (r = 0.792), root length (r = 0.920), shoot fresh weight (r = 0.873) and root dry weight (r = 0.828) were significantly correlated (P< 0.01) with SVI. Seedling root length appeared to be the strongest morphological trait for allelopathic assessment of maize seedling.