- Widespread distribution. Southeast Asia, Caribbean, Oceania. On coconuts. An important disease of seedlings.
- The fungus attacks well-maintained seedlings, but is worse on those in crowded nurseries with poor nutrition and dense shade.
- Spots merge causing a serious blight and leaves dry up and die early. Spread of spores occurs in wind and rain. It is unimportant after transfer of seedlings to the field.
- Cultural control: ensure correct nutrition: the balance between N (too much increases blight) and K is important; space plants allowing good air circulation so wet leaves dry rapidly; shade should be low or absent.
- Chemical control: Unlikely to be needed; if required use copper, mancozeb or chlorothalonil.
Pacific Pests, Pathogens, Weeds & Pesticides
Coconut seedling blight (075)
Coconut seedling blight
Bipolaris incurvata (previously known as Drechslera incurvata, Helminthosporium incurvatum). Another species, Bipolaris setariae (Cochliobolus setariae) was identified causing a leaf spot in nursery gardens in Hainan Province, China, in 2012.
AUTHORS Helen Tsatsia & Grahame Jackson
Information from CABI (2019) Bipolaris incurvata (coconut leaf spot). Crop Protection Compendium. (https://www.cabi.org/cpc/datasheet/19827); and McKenzie, E. (2013) Bipolaris incurvata: PaDIL - http://www.padil.gov.au; and from Uchida JY (undated) Bipolaris incurvata. Crop Knowledge Master. University of Hawai'i at Manoa. (http://www.extento.hawaii.edu/kbase/default.htm). Photo 1&2 Kohler F, et al. (1997) Diseases of cultivated crops in Pacific Island countries. South Pacific Commission. Pirie Printers Pty Limited, Canberra, Australia.
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.