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Watermelon

Citrillus lanatus (Thumb.) Mansf.

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Symptoms induced in controlled conditions (fumigation with ozone)

cv. Sugar Baby

Initial lesions caused by ozone exposure on watermelon leaves cv. Sugar Baby appears as a small stippling, decoloured and interveinal (A), upper surface of affected leaves was eroded by effect of the pollutant. Ozone lesions turn into necrotic or brown injuries on the margin of the leaf, a severe chlorosis on whole affected leaf is also observed (B).

Symptoms observed in the field

cv. Reina de Corazones

Ozone-like symptoms were observed in commercial field of watermelon cv. Reina de Corazones, as a necrotic lesions on the upper surfaces of old leaves of the plants (A, B and C). In the beginning the injuries appears as a decoloured stippling (E). Necrotic spots can be ivory in advanced stages (D).

© 2009 Fundación CEAM © 2009 Copyright of the photos: their authors