Comparative efficacy of three plant extracts for the control of leaf spot disease in fluted pumpkin (Telfairia occidentalis Hook F.)

The production and leaf quality of Fluted pumpkin ( Telfairia occidentalis hook f) in Nigeria are threatened by leaf spot and blight. The comparative efficacy of Siam weed ( Chromolaena odorata ( L.), Utazi leaf ( Gongronema latifolium and Bitter leaf ( Vernonia amygdalina ) and a synthetic fungicide (Forcelet) against the mycelia growth of the leaf spot pathogen ( Phoma sorghina ), leaf spot disease, growth and yield of fluted pumpkin ( Telfairia occidentalis hook f) was studied in vitro and in vivo . In 2013 and 2014. The experiments design for the in vitro experiment was Completely Randomize Design (CRD) with six replicates and Randomize Complete Block Design (RCBD) with four replications in the in vitro study. All plant extracts consistently inhibited the growth of P. sorghina in vitro , and suppressed leaf spot development by between 26.2 and 53.54% in 2013 and by between 26.3 and 51.79% in 2014 under field conditions. Leaf and pod yield were also enhanced, C. odorata leaf extract was significantly (p≤0.05) superior to all other treatments followed by V. amygdalina whose effect did not differ significantly (P≥ 0.05) from Forcelet in all the parameters measured. These results show that leaf extracts of C.odorata and V. amygdalina could be used for the control of leaf spot disease and enhanced yield in fluted pumpkin. Keyword : Efficacy, Plant extract, Control, Leaf spot disease, Yield.