2019 ASHS Annual Conference

Sweet Potatoes have been an important staple in the Hawaiian islands and throughout the Pacific for centuries. The plants ability to be stored, high nutritional value, reliability to yield in drought or poor soil and versatility is the reason for this. The importance of sweet potato eclipsed taro in some dry leeward areas of Hawaii. Like all of the canoe crops, a plethora of varieties of U’ala were developed and maintained by the Hawaiians. These cultivars are genetically distinct from the newer varieties now commercially grown in the state, which are descended primarily from Japanese germplasm. The traditional varieties have been displaced throughout the state because of their growth habits, maturation time, pest resistance and yield are not easily adapted to commercial production.

Sweet Potato growers, like all farmers in the state are facing increasing pressure from high production costs. These include land prices, labor and import competition from the mainland. Imports of Asian type and orange flesh type sweet potatoes have forced local growers to leave the industry, switch to higher value shorter rotation crops or to concentrate on added value products from sweet potatoes, especially chips. Processing the crop requires infrastructure which is simply inaccessible for small growers, preventing them from being able to produce sweet potatoes economically. Varieties developed from Hawaiian traditional cultivars could be marketed as “Hawaiian Heritage” or similar designation so growers could earn a higher price point without processing. Value added products such as alcohol and desserts

The main purpose of this project is to identify traits in open pollinated crosses of Mohihi that was planted with eleven other varieties of traditional Hawaiian u’ala. This is called a polycross block, common with establishing breeding populations of sweet potatoes. Sexual reproduction in plants allows traits in the progeny to be expressed that are not visible in the parent plants. This is how we will use the crosses to identify traits such as yield, sugar content and basic traits and appearance of tubers. These traits will be used, along with a collaboration in trialing for potential alcohol production to establish the potential for further breeding work. It is hoped cultivar development utilizing traditional hawaiian crops will help farmers, create new marketing opportunities and allow the general population to access traditional Hawaiian foods currently unavailable.