Christmas dinners depend on control of plant diseases worldwide
Cavity spot of
Light leaf spot of brussels sprouts
|Phytophthora infestans causing late blight of
potato. Left and middle: fairly healthy and 10 days later devastated
potato field; right close up of blight lesions with fungal spores.
Caused a social disaster in Ireland in 1840s and still one of the
hardest diseases to control.
pod and black pod of cocoa
|Frosty pod is currently the most serious disease of
cocoa in the Americas. Should it escape to West Africa, the main
producer of cocoa, it would be catastrophic. Photo courtesy of CABI.
||Black pod of cocoa caused by a species of
Phytophthora can cause total loss of pods. It has spread across
West Africa and requires combined cultural and chemical control. Photo
courtesy of CABI.
Rice is a major food crop for more than one third of the world and
Magnaporthe blast of rice is recognised as one of the main threats to
world food supplies.
Cassava mosaic virus
|Left: Effects of cassava mosaic virus in Uganda. Note
distorted leaves and virtually no yield. These farmers were desperate
following almost complete crop failure. Right: In a non-affected area
in Togo - how the starch-filled roots should appear. Cassava is not
well known in N Europe but is the fourth most important staple in the
tropics feeding around 600 million people.