Flowering and Fruiting Data for Purple-fruited Pitanga (Eugenia uniflora L.) Grown in Hawaii at the Kona Experiment Station Aid in Selection of Potential New Varieties

Thousands of species of plants produce various industrial, edible or medicinal components, but fewer than 100 plant species yield almost all of the food products available on a commercial scale worldwide. Pitanga, however, is not a newly discovered fruit, although its commercial potential has not been widely developed except in its native Brazil. European explorers discovered the pitanga in South America several centuries ago and spread red-fruited seedlings throughout the tropics worldwide. Introduced to Hawai‘i in the nineteenth century, fruits have long been popular in farmers’ markets and are in demand by chefs and processors. Interest in the crop has expanded rather recently because of the availability of purple-fruited, high-antioxidant, better-tasting, sweeter fruits. Recently, several purple-fruited selections were introduced to growers in Brazil. In Florida, the tasty and prolific ‘Zill Dark’ purple-fruited cultivar has been available for many years and is the parent plant of the large seedling field of pitanga planted at the Kona Experiment Station. Factors that have limited further development of purple-fruited pitanga include considerable variation among seedlings and their fruits, difficulty in clonal propagation and lack of recognizably superior cultivars. The planting at Kona has 137 seedlings from a ‘Zill Dark’ self-crossing and 20 grafted plants of ‘Zill Dark. As the planting has matured, the plants have been evaluated for pest and disease problems and fertilizer and water requirements. Fruits from individual plants have been evaluated for antioxidant content, flavor, fruit weight, seed size and post-harvest quality. From 2013 to 2015, all individual plants were evaluated weekly for presence of flowers and/or fruits in various stages of development. Analysis of the flower and fruit data collected may allow selection of early- and late-bearing plants so that the fruiting season for the crop may be substantially increased. Fruit characteristics of early- and late-bearing plants are being evaluated further.