EFFECTS OF AQUEOUS PLANT EXTRACTS AND INORGANICFERTILIZER ON THE GERMINATION, GROWTH ANDDEVELOPMENT OF MAIZE (ZEA MAYS L.)

Screen house experiments were carried out to examine the effectsof aqueous leaf extracts of Tithonia diversifolia (Ti) and Vernonia amygdalina(Ve), as well as NPK fertilizer (15-15-15) on the germination, growth anddevelopment of maize. Fresh leaves were collected, washed with tap water,chopped and pounded, soaked in distilled water and filtered. The two filtrates wereused to prepare extracts at 50 and 100% w/v. Four maize seeds were placed in Petridishes laid out in a completely randomized design with five replicates. In everyPetri dish 10 ml of extract per treatment was added. A control experiment withdistilled water was also set up. Also, in a completely randomized design with fourreplicates, 4-week-old potted maize plants were treated with 500 ml of each extractas well as with 1.52 g of NPK fertilizer. The results showed that the germinationpercentage of the seeds followed the order Ti50 - Control - Ve50. The seeds treatedwith aqueous extracts of T. diversifolia and V. amygdalina at 100% w/v producedlower but equal germination percentage. The seedling radicle growth wassignificantly inhibited by the aqueous extracts of Ti100, Ve50 and Ve100 (p≤0.05).The inhibition was dose-dependent and more pronounced in seeds treated withextracts of V. amygdalina. The aqueous extract of T. diversifolia (50% w/v) andcontrol influenced radicle growth substantially. All the extracts inhibited theplumule development compared to the control. On the other hand, growth,development and yield were not significantly affected by the plant extracts.