Status: 🌱

Genealogy

♀: Shizu 7132

♂: Asatsuyu あさつゆ

Tsuyuhikari is a high-yielding, slightly early variety with high resistance to Anthracnose, fresh aroma and bright light colour.

History

Breed in 1970 at the Shizuoka Prefecture Tea Experiment Station with Shizu 7132 as the mother and Asatsuyu as the father. This strain, named 70-30-302 in particular, was selected individually again in 1979. Then again, in the Nutritional Comparison Test from 1982. Tests from 1991 to determine cultivar variety promotion, tested for productivity and characteristics, and regional adaptability until 1997.

It was named Tsuyuhikari in 2000. The name inherits part of the meaning from one of its parents, Asatsuyu あさつゆ, regarded for its superior quality. The latter meaning of the name is light. Meaning it will bring a new light to the tea industry.

The cultivar was highly regarded even before registration as a tea cultivar. The registration process began in September 2000, although not officially published in the Seeds and Seedlings register until the 13th of March 2001. After a selection process in a committee in February 2001, it became adopted as one of the main cultivars in the Shizuoka Prefecture tea cultivar promotion variety from April 2001. During that year, due to the selection as a tea cultivar promotion, its usage in the fields increased rapidly. Registration concluded under the Seeds and Seedlings Law on the 17th of March 2003 with registration number 11103.

Although Tsuyuhikari was selected as the main cultivar for promotion and promoted as "a new face to replace Yabukita", there were two other cultivars. Koushun (香駿 こうしゅん), for it's aromatic characteristics and Yamanoibuki (山の息吹 やまのいぶき) for its easy cultivation and early shooting. These three were promoted around the region to promote cultivar diversity.

According to the data of 2001, Yabukita represented 77% of the cultivated tea area in Japan and 91% of the Prefecture of Shizuoka 静岡. Using data from a recent study from March 2023, in 2015, there were 80 ha of Tsuyuhikari in the Prefecture with 165 ha as of 2022, an increase still far from the 16.473 ha of cultivated Yabukita in 2015 (92.5% of the Prefecture). Yabukita has steadily decreased to 12.319 ha in 2022, 89.3% of the Prefecture. An interesting data point is that the decrease in Yabukita does not correspond to an increase in the other cultivars. Tsuyuhikari is the only cultivar whose cultivation area has increased considerably. Most others have remained approximately the same, only Okumidori (おくみどり) and notably, Zairai (在来種) have increased their ha from 86 to 105 and from 156 to 185, respectively. The total cultivated area has been considerably reduced in the past years from 20.800ha in 2001 to 17.801 in 2015 and 13,800 in 2022, approximately 25% loss in 20 years.

Omaezaki, Tsuyuhikari City

The tea cultivar variety promotion had a particular success case divulging Tsuyuhikari as a cultivar for the Prefecture. Some growing areas, like Omaezaki City, focused on the Tsuyuhikari cultivar as a selling point for the tea grown in the area. Promoting the tea made in the region using the cultivar in the Tsuyuhikari Cafe, operated by the Omaezaki City Tea Industry Promotion Council. They promote tea sales in shops, including surf and golf shops and facilities, as well as with sweets makers. Even a fountain pen ink was developed, together with a famous stationery shop in Tokyo, showcasing the bright green colour of the brewed tea.

In 2001, the local tea promotion council, concerned with the current trends, started exploring several ways to promote tea in the region. After an initial round of promotional activities, they started exploring other ways to boost sales. The homogeneity of the Yabukita cultivar and standardised production methods in Shizuoka didn't favour the municipality, and using new tea cultivars was considered a possible solution. In December 2001, further exploring the idea was decided.

In January 2002, the chief researcher at the Shizuoka Prefecture Tea Research Institute was invited as a lecturer to study several qualities of different varieties for the region. The following cultivars were explored: Meiryoku (めいりょく), Saemidori (さえみどり), Okumidori (おくみどり), Okuhikari (おくひかり), Yamanoibuki (山の息吹 やまのいぶき), Koushun (香駿 こうしゅん), Fushun (ふうしゅん), Asatsuyu (あさつゆ) and Tsuyuhikari, at that time still an unregistered cultivar and still used a provisional name. Tsuyuhikari just started being promoted as a cultivar in the Shizuoka prefecture in April 2001.

Tsuyuhikari flavour characteristics, especially the lack of a characteristic astringency present in Yabukita, were one of the reasons Tsuyuhikari was selected.

The project did have its ups and downs, with the town, the farmers and merchants involved. The city would provide the seedlings, the farmers would grow them, and the merchants would buy and sell the tea. That was the game plan for the regional tea promotion. And also its main pain point, with many parts involved. Obtaining the tea seedlings and then growing them for 3-4 years before production volumes were possible. Afterwards, the merchants needed to be able to buy and sell the tea of the region.

Once all the agents involved were lined up and decided to act together towards a common goal, budgets were planned and approved. Then, a license agreement had to be reached, as the cultivar rights belonged to the Shizuoka research centre for 25 years, expiring in 2028. Until then, special permission to sell tea made with the Tsuyuhkari cultivar is necessary. At some point, the Shizuoka Prefecture became protective of this cultivar, and now it is only possible to buy seedlings inside the Shizuoka Prefecture. So, it is rare to find it outside of it with permission to sell it.

On the 26th of June 2002, after approval, on the previous day at the meeting of the Executive Committee, the Tea Research Institute handed 1000 seedlings of Tsuyuhikari. Those were distributed to the JA in Hamaoka city to start propagation as per the agreement for licensing once the cultivar was registered. After the registration of the cultivar in March 2003, in April of the same year, a license was granted for a period of 3 years to Hamaoka, marking the official start of Tsuyuhikari as a cultivar in the region. One year later, due to the merging of Hamaoka City and Omaezaki City, the Tea Promotion Council's name changed to the current Omaezaki City Tea Industry Promotion Council. The licensing for the cultivar is currently renewed and maintained. In 2007, the city began full-scale sales of the variety ahead of other production areas, and its popularity is growing year by year as Omaezaki's mainstay variety.

Characteristics

In the tea nursery, the seedlings grown on the floor had a lower survival rate of 56% compared to the 76% of Yabukita. Other measurements, like the number of shoots and leaves during the first year and height, growth and uniformity in the second, were also inferior to Yabukita. Studies to improve survival rates and avoid the defoliation of the plants report positive results by utilising windbreaks and growing under tunnel cover. The growth and survival rate increases after the third year. This initial round of tests was between planting in 1980 and 1981.

As for the growth in paper pods, data from 2002 measured growth at 3 and 5 months. The overall growth of Tsuyuhikari was inferior except for a slightly higher number of leaves. The survival rate at this stage is quite similar for Tsuyuhikari and Yabukita in the study, at 96% and 99%, respectively. Rooting of cuttings is slightly poor but has good growth of seedlings after firm root establishment.

The young trees were tested from 1991 to 1993, during which growth of the first three years was evaluated. The height of the tree was around the same as Yabukita. The tree trunk was broader than Yabukita, with a taller stump height, around 20cm higher, at seven years old at the test location. The growth during the initial 3-year period is vigorous, and on the 3rd year mark, the autumn harvest is already almost double that of Yabukita. Budding time is one day earlier than Yabukita, and harvesting is up to two days earlier, thus placing Tsuyuhikari in the slightly early cultivar category.

It presents an intermediate-type shape and vigorous growth with a good alignment of tea buds during the harvest season. New leaves are bright light green with a leaf shape between oblong and elliptic. Adult leaves are green and long-ovate with a slightly less wavy surface. With a tad larger number of buds and a higher hundred-bud weight than Yabukita, it is considered a bud-heavy type tea cultivar.

In Shizuoka, two independent research institutions regarding tea operate close to each other. The Shizuoka Prefectural Tea Research Centre. And the National Tea Research Centre under NARO. In this case, I will refer to the Shizuoka Prefectural Tea Research Centre unless otherwise stated.

The Shizuoka prefectural tea research centre has its main fields and installations on the grounds of its research centre in Makinohara, where construction of an open innovation tea research centre is ongoing and will open in 2025. There are two more facilities, a field in Fuji city and an Agricultural and Forestry Centre in Kawane town, both in more mountainous areas, where the trials for mountain growing conditions are carried out, also known as regional adaptability trial sites. The research on Tsuyuhikari in the Kawane research site revealed similar results to the ones in the plateau. Vigorous growth overall, the rate of growth for the new leaves was also higher compared to Yabukita. While the budding and picking period were the same as Yabukita in the Fuji field, it was two days earlier in the Kawane centre. The tests took place between 1991 and 1993.

Cold resistance and Red Blight incidence is about the same as Yabukita in the same area and could be grown anywhere in the country. In both the Fuji and Kawane sites, incidence was similar, slightly less at the Kawane site. As for Anthracnose, the damage was significantly lower than for Yabukita and the two other cultivars used during the trials at the research centre fields. Kurasawa (くらさわ) being similar to Yabukita, both weak to Anthracnose and Sayamakaori (さやまかおり), known to be very susceptible to Anthracnose. The Fuji and Kawane test sites had similar trends, but the Kawane site showed the biggest reduction for all cultivars. Tsuyuhikari mostly being unaffected. It is slightly resistant to the glutinous disease, like Yabukita and more resistant than Kurasawa.

Yield for Tsuyuhikari in a 4ha area is generally higher than Yabukita by around 130% when counting the first and second harvests. Yield is higher in the autumn harvest. The number of buds and their weight are roughly the same when averaging four years, corresponding to an age of 4 to 7-year-old bush. The average buds are slightly shorter but heavier, with almost identical bud count. The mountain test sites experienced a similar trend, with the Fuji site at 165% higher than Yabukita, nearly doubling the production amount in the second harvest. The Kawane site had a higher overall yield at 126%, particularly at the second harvest at 146%, but very similar to the first harvest, at 106%.

The harvest data for the mountain sites was scrapped in 1994 at Fuji due to generalised frost damage that affected yields for all fields at the trial site. In 1993, at age 3 of the seedlings, the fields were not harvested in the Kawane site.

In aracha, the average score for a 4-year study was similar to Yabukita, with the shape and aroma being rated higher than Yabukita for first harvest tea. Once rolled, the shape of the leaf is good, with a bit of a powdery appearance and a bright green colour. Thus, the brew has a bit of sediment and turbidity with a bright green colour. It also presents a nice green colour when deep steamed. Due to the fresh leaf characteristics, it is challenging to shape during production, and powder tends to occur. It requires extra care with the production conditions.

The aroma is fresh, and the flavour has mild umami in harmony with a good textured body. In particular, its aroma and brew colour are praised and offer a distinctive but different experience. As for the results of the mountain test sites, aracha evaluation shows similar results. With aroma, in particular, for the first harvest in the Kawane site being the highest.

Chemical composition revealed more Nitrogen, free amino acids and L-Theanine with less tannin than Yabukita and other compared cultivars in the first harvest. Caffeine was also slightly lower than the rest of the cultivars. As for the second harvest, most values were the same if compared to Yabukita, but with a lower tannin content. These are from a 2001 study.

In 2003, a survey carried out at an agricultural forum provided insight into the Tsuyuhikari reception by both producers and consumers. 41% either liked or slightly liked it. Far away from the 16% that either disliked or slightly disliked it. The most common description was "light" at 50%, with umami at 38% and sweet at 29%. Bitterness and astringency were the least common at 9% and 6% respectively. The aroma was highly appreciated, at 51% combined, while the tea aroma was considered weak. The brew colour was considered a light and fresh colour. A general description would be a light, refreshing tea that could be drunk daily.

Tsuyuhikari Summary

Tsuyuhikari has excellent disease and cold resistance, making it suitable for tea-growing areas throughout the country. Both in flatlands and mountain areas, including those areas with volcanic soils. It has high resistance to red blight and high resistance to Anthracnose. It has vigorous growth and slightly early shooting growth. The leaves are prone to powdering during the processing of the tea leaves and need more careful management during processing. Tsuyuhikari is a cultivar recommended for Sencha 煎茶 production. Used as a cultivar for deep-steamed teas and for Tencha 挽き茶・碾茶 and Kamairicha 釜炒り茶 production.

Its use for fully oxidised and partially oxidised teas is also possible. The aromatic profile of Tsuyuhikari combined with the Kaori Ryokucha 香り緑茶 processing techniques developed by the Shizuoka prefectural research centre have a great synergy and actively explored in aromatic-focused tea production. The Association for the Promotion of Fragrant Tea, formed by the Katsumata-Kaitaku Cooperative, produces tea using the research on aromatic teas by the prefectural research station, just a few minutes walk from the cooperative factory.

Breeder's rights under the Seeds and Seedlings Act will remain in force until 2028. Until then, seedlings can be exclusively from nurseries with licensing agreements with the Shizuoka Prefectural Research Centre. After that date, seedlings are available from nationwide nurseries. Although Tsuyuhikari is used in many production farms around the country, in recent years, the low availability and the Prefecture becoming more protective, with seedlings only being sold inside the Prefecture, make it a rare cultivar outside the Shizuoka Prefecture.

I decided not to include other details here as the table of results (Table 21) has identical results for both locations and all four cultivars, except for the reported results for the first harvest in the Kawane site.

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References

Oyaizu, Tsutomu, et al. “A New Cultivar ‘tsuyuhikari’ for Green Tea.” Chagyo Kenkyu Hokoku (Tea Research Journal), vol. 2003, no. 95, June 2003, pp. 1–15, https://doi.org/10.5979/cha.2003.1.

A shorter translated version of the Tsuyuhikari cultivar paper above. https://www.ocha-festival.jp/archive/english/conference/ICOS2001/files/PROC/II-144.pdf

Tea Promotion Division, Agricultural Bureau, Department of Economy and Industry, Shizuoka Prefecture. 静岡県茶業の現状 Current State of the Shizuoka Tea Industry . Mar. 2023. https://www.pref.shizuoka.jp/res/projects/defaultproject/page/001/027/288/cyagyonogenjyo.pdf.

Team, Green Tea Merchant. “What Is Tsuyuhikari (御前崎茶-つゆひかり) Cultivar?” Green Tea Merchant Blog, 14 June 2022, https://www.shizuokatea.com/blog/what-is-tsuyuhikari-御前崎茶-つゆひかり-cultivar/.

World Green Tea Association. “Tsuyuhikari.” O-Chanet, https://www.o-cha.net/english/teacha/cultivar/tsuyuhikari.html. Accessed 30 Aug. 2023.

http://www.hinshu2.maff.go.jp/vips/cmm/apCMM112.aspx?TOUROKUNO=11103&LANGUAGE=Japanese

Tsuyuhikari MAFF Cultivar Registration Database page.

井上製茶園 Inoue Seichaen website. https://inoue-seichaen.com.

静岡県農林技術研究所 茶業研究センター Shizuoka Prefectural Agricultural and Forestry Research Institute, Tea Research Centre. Improved Rooting Characteristics and Early Growth of Tsuyuhikari.

https://www.pref.shizuoka.jp/res/projects/defaultproject/page/001/044/307/033.pdf.

Report showcasing several projects related to tea by the Regional Crops Division, Department of Agriculture, Bureau of Production. Published 26 February 2015. https://www.maff.go.jp/j/seisan/tokusan/cha/pdf/cha2.pdf