Photo 1. The beginning of symptoms on cocoyam, Xanthosoma, showing early death of the older leaves caused by Pythium sp. (Solomon Islands.)
Photo 2. Pythium infection in Colocasia taro showing weak-looking plants with two at most three leaves, and new leaves which are stunted and partly rolled. (Samoa.)
Photo 3. Typical dieback caused by Pythium root rot. Notice the disease has travelled down a row, most likely by root-to-root contact. (Cook Islands.)
Photo 4. Pythium infection on cocoyam, Xanthosoma. Removal of the plants, and washing the roots, shows that the root system has been destroyed. Many of the larger roots are black, and side (fine) roots are absent.
Photo 5. A plant from Photo 1, pulled up to show the decay of the roots. Notice the difference between the roots at the top of the picture, which are mostly without side (fine) roots, compared to those below.
Taro root rot, cocoyam root rot, Pythium root rot of taro (cocoyam)
AUTHORS Helen Tsatsia & Grahame Jackson
Photo 3 William Wigmore and Maja Poeschko, Ministry of Agriculture, Cook Islands.
Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.
This mini fact sheet is a part of the app Pacific Pests and Pathogens
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