Effect Of Crude Bulb Extract Of Allium Sativum On Wilt Diseases Of Tomato Under Invivo Conditions
Pot experiment was conducted from October to February 2015/16 dry season at the research farm of Plant Biology
Department, Bayero University Kano Nigeria, to evaluate the effectiveness of aqueous bulb extract of Allium sativum on
wilt diseases of three varieties of tomato caused by single and synergistic inoculations of Fusarium oxysporum, Fusarium
solani and Rhizoctonia solani. Tomato plants were inoculated with spore suspensions of the test pathogens. Aqueous bulb
extract of A. sativum as treatment was applied as soil drench post innoculation. Plants in uninoculated untreated soil/pots
served as check. The application of A.sativum aqueous bulb extract was repeated twice at two weeks intervals. All pots were
arranged in a Randomized Complete Block Design with four replications. Data were collected on chlorophyll content,
disease incidence, yield loss and total fruit yield(kg/ha). Results showed significant improvements in growth and yield of the
three tomato varieties. Highest chlorophyll content (SPAD) was recorded in Romavf synergistically inoculated with F.
oxysporum + F. solani (40.29) and F. oxysporum + R. solani (40.16), treated with A. sativum aqueous bulb extract. The
greatest reduction of disease incidence was achieved by the application of A. sativum crude bulb extract on Romavf, while
the local variety showed least reduction in disease incidence and severity in the single and synergistic inoculations of the
pathogens. Yield loss was higher in the local variety except in the single inoculation of R. solani treated with the extract
(9.50). Total fruit yield (kgha -1 ) was improved by the application of A. sativum aqueous bulb extract in all the tomato
varieties. Highest fruit yield was recorded in variety RomaVF inoculated singly with F. solani (8501kgha -1 ), treated with the
extract. However, A. sativum aqueous bulb extract was more significant on total fruit yield in the local variety inoculated
singly with R. solani (5589kgha -1 ) showing resistance of the variety to the pathogen. Findings from this study confirmed that
plant extracts can be used as natural fungicides to control pathogenic fungi of tomato plants.
Keywords: Allium sativum, aqueous, Fusarium oxysporum, Fusarium solani and Rhizoctonia solani.