Tomato production is faced with many fungal diseases including alternariosis and
anthracnose caused by Alternaria solani and Colletotrichum sp. respectively, which
cause major losses in production. Identify effective biofungicidal formulations based
on extracts of Eucalyptus camaldulensis Dehnh. and Cymbopogon citratus (DC.) Stapf
on the radial growth of Alternaria solani and Colletotrichum sp. The efficacy of
aqueous or ethanolic extracts of Eucalyptus camaldulensis or Cymbopogon citratus as
well as combinations of aqueous extracts (4/1; 3/1 and 2/1) on the radial growth
and sporulation of Alternaria solani and Colletotrichum sp. was studied in vitro. Then
incubated at 25°C under an alternating 12/12 cycle of near ultra-violet light and
darkness. The inhibition rate was measured on days 2, 4 and 7 after incubation (DAI)
and for sporulation on day 14. All the extracts of the two plants, aqueous or
ethanolic, showed the maximum inhibition rate (100%) on the radial growth of
Alternaria solani and Colletotrichum sp. at concentrations of 20% and 30%. On the
other hand, the combination of aqueous extracts was only effective at the 30% dose
with inhibition rates of 49% on Alternaria solani and 21% on Colletotrichum sp. At
doses of 20% and 30%, aqueous or ethanolic extracts of Eucalyptus camaldulensis or
Cymbopogon citratus completely inhibit the mycelial growth of Alternaria solani and
Colletotrichum sp.

Alternia solani Biofungicides Colletotrichum sp. Plant extracts Tomato