Tsuyuhikari

Tsuyuhikari is a Shizuoka sencha cultivar registered under the Plant Variety Protection Act in March 2003, and it is one of the very few records in this collection whose both parents are also records here. Its seed parent, Shizu-7132, is a 1960s Yabukita seedling that was never named or registered and is known only by its trial number — a plant with a genuine coumarin-driven cherry-leaf aroma that Shimizu growers sell locally as “Machiko”. Its pollen parent is Asatsuyu, one of the Uji landrace selections registered in the very first Cha Norin batch in 1953.

Lineage

• Shizu-7132 ♀ (静7132) — an unregistered Shizuoka breeding line, itself an open-pollinated Yabukita seedling.
• Asatsuyu ♂ (あさつゆ) — Cha Norin No. 2, a Uji zairai selection.

The name follows the cross: つゆ from Asatsuyu, the same way Saeakari takes さえ from Saemidori. It is one generation below the Shizuoka landrace on one side and the Uji landrace on the other, which makes it a fairly direct joining of the two lines that most of Japanese tea breeding runs on.

History

Crossed in 1970 at the Shizuoka Prefectural Tea Experiment Station, with individual selection in 1979 and trials running through to 1997. The release paper — Oyaizu et al., 茶業研究報告 No. 95, 2003 — was published the same year as the registration, which was granted on 17 March 2003 as Plant Variety Protection Act No. 11103. No Cha Norin number was found for it, consistent with a prefectural release of that period.

The detail worth recording is what happened afterwards. Cultivation outside Shizuoka was restricted in 2021, which makes Tsuyuhikari one of the few cultivars in this collection whose distribution is capped by policy rather than by agronomy or by taste. Whatever its merits, it is not going to become a national cultivar.

Characteristics

Budding runs about a day earlier than Yabukita and plucking up to two days earlier — slightly early, close enough to the reference that it does not much extend a picking season on its own. Yield is the stronger argument: around a third above Yabukita over the first and second flushes combined, with an autumn crop reported as particularly strong.

Disease resistance is genuinely good where Yabukita is worst. Anthracnose resistance is high — the single most useful thing a Shizuoka cultivar can offer, given that Yabukita’s susceptibility to it drives a large part of the region’s spray programme — and red-scorch resistance is high too. 赤枯れ is the winter cold injury itself, so cold tolerance runs better than Yabukita’s rather than level with it. What is only level with Yabukita is blister blight (もち病).

It is used for sencha and, in Shizuoka, particularly for deep-steamed sencha, with reported use for tencha and kamairicha as well and some potential for oxidised styles. That range is wider than most sencha cultivars manage, and is the other half of the case for it.