2019 ASHS Annual Conference

Taro leaf blight, caused by Phytophthora colocasiae Racib, is the most important and damaging diseases of taro worldwide. Taro leaf blight could reduce taro corm yield by 50% or more in highly susceptible taro cultivars. Leaf yield losses of up to 95% have occurred for susceptible cultivars in Hawai‘i. Epidemics could completely destroy susceptible cultivars in the field. Poi quality could be reduced, because reduced photosynthesis could result in decreased production of gums and starches. Resistant cultivars offer the best sustainable management strategy against taro leaf blight. However, desirable characteristics and qualities are often lost during breeding. Thus, breeding for taro leaf blight resistance should focus on maintaining or improving desirable qualities, such as larger corms, shorter time to plant maturity, and improved taste and texture. Taro Leaf Blight resistant cultivar trials are being conducted throughout the State on Hawaii. The cultivars with greater than 50 % higher yields compared to the control Hawaiian cultivar (Maui Lehua) were 1016-03, 1003-03, 1003-13, 1024-209, 1024-15 and 1005-84. The cultivars 1016-03 and 1003-3 were the most desirable with good flavor, sweetness, stickiness and overall eating quality. These new cultivars are potential alternatives for taro growers in Hawaii.