INTRODUCTION
Persimmon (Diospyros kaki Thunb.) is temperate-zone deciduous fruit tree native to East Asia, originating from China, and known to have spread to Korea and Japan.
Currently, it has been cultivated widely in temperate regions such as the United States (California), Italy, Israel, Brazil, Australia and New Zealand (Ma et al., 2020).
Persimmon is classified into four types as its fruit astringency at harvest time (Hume,1914; Kajiura, 1946), and the pollination-constant non-astringent (PCNA) type is the most preferable fresh one among the four types. The PCNA type is characterized by stable and natural loss of astringency; this character is caused by lack of the ability to accumulate a large amount of tannins (Yonemori & Matsushima, 1985).
The production of high-quality persimmon fruit is critical to sustaining and promoting consumption in the domestic and export markets. Most (85.9%) of the world’s persimmon fruits are produced in Asian region (FAO, 2017). Consumers in Asian countries seek the more sweetness in persimmon fruits. So, in the highly competitive and consumer- driven markets, persimmon growers are consistently requested to supply fruits that meet or exceed consumers’ expectations, the sweetness. The market of persimmon fruits in Australia is expanding in line with consumer’s strong interest in functional healthy foods, increased immigrants from Asian countries and its exporting market expansion. This is an opportunity for persimmon to become a mainstream product in Australia. However, there are no sufficient persimmon varieties in Australia to meet future demands for increased immigrants and exporting market expansion. There is a need for early- and late- maturing persimmon varieties to extend their harvest window in Australia. Also, rootstocks suitable for various growing regions and varieties of Australia should be improved to enhance productivity and quality of persimmon fruits.
CURRENT STATUS OF PERSIMMON INDUSTRY IN AUSTRALIA
1. Cultivation area and production of persimmon
Australia, the 16th producing countries in the world, produced 2,519 tons in 2018. The 42% of the total persimmons fruits production is produced in Queensland, followed by 23% in New South Wales, 22% in Victoria, 8% in South Australia and 5% in Western Australia. The harvest season starts from March to April in Queensland and from April to June in the other states. 90% of the harvested fruits are used for fresh consumption, 7% for export, and 3% for processing (Persimmon strategic investment plan 2017-2021). The wholesale value of the fresh persimmon supply was $13.5 million in Australian dollars. Nine percent of households in Australia purchased fresh persimmons of average 508 g per shopping trip. The 80 growers produced persimmon fruits in 5 states of Australia (Table 1).
Persimmon fruits are imported in Australia from July to November. In 2018, its volumes touched 445 tons. But export volumes were only 183 tons in 2018, with the importing countries being Malaysia, Singapore, Hong Kong and Thailand.
2. The traits of major and leading persimmon cultivars in Australia
Australia has only 2 major varieties, ‘Fuyu’ and ‘Jiro’. The others include ‘Izu’, ‘Suruga’, ‘Yang Fang’ and ‘20th Century’.
1)‘Fuyu’
‘Fuyu’ is a non-astringent persimmon cultivar and the most widely cultivated in the world. It has a squat and rounded fruit shape, with an orange pumpkin-colored skin. Their texture varies from crispy and succulent when young, to a tender and gelatinous as they mature.
2) ‘Jiro’
‘Jiro’ is one of the best non-astringent cultivar, and the sweet and mild flavored fruit shows round oblate in shape and medium size, ranging 7.0-8.5 centimeters in diameter. The flesh contains pale orange hues and has a slippery and firm consistency. Jiro fruits have a sweet and mild flavor. The tree has smooth gray to tan bark and is upright reaching heights of 4-5 meters. Fruits ripen in fall to early winter.
3) ‘Izu’
'Izu' persimmon, dwarf trees, is very productive. It has non-astringent fruits, with a crunchy, pale orange flesh and smooth texture. The fruits show a slightly flattened shape, likely pumpkins or a tomato fruits. Its medium-sized fruits, seedless or few- seeded, ripen to a burnt orange skin. The fruits can be eaten when they are firm, or just begins to soften.
4) ‘Suruga’
‘Suruga’ persimmon (hybrid of ‘Hanagosho’ and ‘Okugosho’) has a small-medium sized, orange-red fruit and its non-astringent flesh is even sweeter than ‘Fuyu’, due to over 20% soluble solid contents. Also, fruit imperfections are extremely infrequent. As it ripens in November, the site with warm climates is recommended for the cultivation. The seeded fruits must be thinned to prevent over production.
3. Characteristics of Korea-bred new persimmon varieties being tested for adaptability in Australia
In spite of worldwide production of persimmon, its new cultivars have been cross-bred and released only in Japan and Korea. In Japan, new cultivars have been released since 1959 (Sato & Yamada, 2016). Persimmon in Korea has also been a major fruit crop for many years, but first release of new variety was done in 2008. And since 2014, several varieties with various harvest times and high fruit quality have been released.
In Australia, the new persimmon with various harvest times are needed to expand the consumption period and to meet the increased consumer’s demand. So, Australia concerns want the Korea-bred new persimmon cultivars such as ‘Fantasy’, ‘Gampung’, ‘Wonmi’, and ‘Wonchu’ which are going to be tested for regional adaptability in the arid Australian climate condition from 2021.
1) ‘Fantasy’
‘Fantasy’ was derived from the cross with ‘R19’ and ‘Taishu’ in 2012, with medium size (230 g) and even sweeter than 'Fuyu' (16.5 °Bx). It ripens in middle October at Yeongam district, south-east region of Korea and is recommended to be planted in warmer climate regions. The fruit has circle shape, yellow-colored skin and very sweet non-astringent flesh. It has also a high resistance to physiological disorder such as calyx-end cracking and cracking on the fruit skin and so on. Its variety patent was registered in Australia in 2020
2) ‘Gampung’
‘Gampung’, with very big size (417 g) and good sweetness (14.7 °Bx), was derived from the cross with ‘Daeandangam’ and ‘Taishu’ in 2004. It ripens in late October at Yeongam district, south-east region of Korea and is recommended to be planted in warmer climate region. 'Gampung' has round oblate shape, red-orange colored skin and very crispy non-astringent flesh. It also has a high resistance to physiological disorder such as calyx-end cracking and cracking on the fruit skin and so on. Its variety patent was registered in Australia in 2020.
3) ‘Wonmi’
‘Wonmi’, with medium size (221 g) and high sweetness (15.1 °Bx), was derived from the cross with ‘Fuyu’ and ‘Taishu’ in 2005. It ripens in early October at Yeongam district, south-east region of Korea and is recommended to be planted in warmer climate regions. The fruit has round oblate shape, red-orange colored skin and sweet nonastringent flesh. It also has a high resistance to physiological disorders such as cracking on the fruit skin. However, a slight calyx-end cracking occurs.
4) ‘Wonchu’
‘Wonchu’, with very big size (320 g) and high sweetness (15.1 °Bx), was derived from the cross with ‘Shinshu’ and ‘Taishu’ in 2005. It ripens in early October at Yeongam district, south-east region of Korea and is recommended to be planted in warmer climate regions. The fruit has round oblate shape, yellow-orange colored skin and sweet nonastringent flesh. It also has a high resistance to physiological disorder such as calyx-end cracking and cracking on the fruit skin and so on.
CONCLUDING REMARKS
Australia wants to expand harvest season of persimmon by new early maturing non- astringent persimmon varieties such as ‘Fantacy’ and ‘Wonmi’, South Korea-bred varieties. Therefore, the Australian concerned want a Korea's cooperation on the issue. So, variety patent registration of ‘Fantacy’ (selected in 2018) and ‘Gampung’ (selected in 2013) in Australia was done in 2020. And that of ‘Wonmi’ (selected in 2014) and ‘Wonchu’ (selected in 2015) were also in progress. We hope these varieties will be successfully cultivated after local adaptability test in Australia.
적 요
건강기능성 식품에 대한 관심 증가와 아시아계 이민 증가 그리고 수출시장의 성장으로 호주에서 감의 수요는 계속 증가 할 것으로 전망된다. 하지만 호주에서 주로 재배되는 품종인 ‘부유’, ‘차랑’은 수확시기가 한정되어 있어 호주의 미래 감 수 요를 충족시키는 데 한계가 있다.
