Experts Battling to Save Coconut Palms in Hawaii pg.4
Fungicides such as Subdue 2E (metalaxyl), Dithane M-45 (mancozeb), Aliette (fosethyl-Al), and Truban (ethazole) are known to be effective protectants against other Phytophthora diseases, but they are ineffective for curing palms with advanced rots of the heart or terminal bud.
Limited control of the disease in the early stages may be attained by removing diseased fruits on palms that don’t have young dead leaves, then protecting the wound surface with a pruning sealant, thus preventing disease progression into the trunk. A good plan is to plant coconut palms more often. The life span of a coconut palm may be only 15 to 25 years with this disease in Hawaii, thus younger ones should be planted periodically.
From genesis to epidemic proportions
Coconut palms had been relatively disease free in Hawaii, prior to the discovery of Phytophthora katsurae in 1971 by Dr. Minoru Aragaki from a specimen collected at Wailua, Kauai, according to the University of Hawaii College of Tropical Agriculture and Human Resources (CTAHR) in Honolulu. Infected plants died within one year. Aragaki and Dr. Janice Uchida worked on the disease over the years.
During the 1980s, Phytophthora was found on Oahu, Maui and the Big Island. Inter-island movement of nuts, seedlings, and large palms, as well as trimming operations, probably contributed to the disease escalating to epidemic proportions.
Fearful that a centuries-old icon in Hawaii could become extinct in the not too distant future, experts here have launched a concerted effort to combat coconut heart rot. Philippe Visintainer, owner/operator of Hawaii Coconut Protectors on Maui, is leading the battle against Phytophthora with unabashed zeal.
