Post harvest diseases fruits and vegetables - Xavier University ...

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50
40
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Day 1 (control = 0.00%)
Day 2 (control = 0.50%)
Day 3 (control = 1.75%)
"Day 10 (control = 9.56%)
Postharvest Diseases of Fruits and Vegetables
\—I I mil I I iiiiiifi-Ti-'r-rtrtt
10 50 100 500 1000 10,000
Concentration (ppm)
Fig. 1. Effect of orange oil suspension in 1% water agar on germination of
conidia of Penicillium digitatum. (Reproduced from French et al., 1978 with
permission of the American Phj^opathological Society).
Penicillium italicum conidia also. Examination of the various oil
component activities revealed that nonanal and citral were the most
effective compounds. Moreover, a mixture of these two compounds had a
synergetic effect, leading to high germination rates in the conidia
population (French et al., 1978). It appeared that oils produced from
different citrus fruits might differ in their compositions, hence the
relative differences among the stimulating or suppressing activities of
oils produced from different sources.
Since little or no germination of P. digitatum occurred on water agar
alone, it was assumed that substrate nutrition was the determinant of
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