Saemidori

Saemidori is a controlled cross of Yabukita and Asatsuyu, bred at the Makurazaki branch of the Ministry of Agriculture and Forestry’s Tea Research Station in Kagoshima and registered as Cha Norin No. 40 in June 1990, twenty-one years after the two parents were crossed. The pairing was deliberate: Yabukita for field reliability and Asatsuyu, itself prized for early budding and quality, for something Yabukita’s flavour does not really offer. What came out the other end is widely treated as the closest thing Japan has to a successor to Yabukita at the premium end of sencha, and increasingly a matcha cultivar too — high in amino acids, markedly less astringent than Yabukita, and a few days earlier to harvest, which matters a great deal in a market that prices shincha by how early it arrives.

Lineage

• Yabukita ♀ — the seed parent, itself a single-plant selection out of a Shizuoka-type Zairai stand rather than a cross. Contributes field reliability and general vigour.
• Asatsuyu ♂ — the pollen parent, itself a selection out of a Uji-type Zairai stand. The original release paper describes it plainly as chosen for being “early-budding and of excellent quality” (早生で品質優良な).

This is a controlled cross, not a landrace selection, but only one generation removed from one: both parents are themselves individual selections from seed-grown regional stands, so Saemidori’s pedigree effectively terminates in unrecorded seedling parentage on both sides one generation up. Saemidori has in turn become one of the most productive parent cultivars in modern Japanese tea breeding. Documented descendants include Kirari 31 (Sakimidori × Saemidori) and its reciprocal Haruto 34 (Saemidori × Sakimidori), Saeakari (Z1 × Saemidori), Seimei (Fushun × Saemidori), Kiyoka (FYZ-41 × Saemidori) and Danshin 37 (Saemidori × Yumekaori).

History

The cross was made in 1969 at the Makurazaki branch of the Ministry of Agriculture and Forestry’s Tea Research Station in Kagoshima (predecessor to NARO’s present-day Makurazaki tea research site). Seed was harvested in October 1970, sown under glass that December, and the seedlings were planted out in the field in November 1971. From 1975–76 the most promising individual was carried under the number F1 29975 for individual selection trials; cuttings were taken in June 1977 for nursery-bed selection; and from 1978–1984 it ran in strain-comparison trial group 29 under the strain name “系29-9” (Strain 29-9), tested for yield, processing quality as sencha, and general characteristics.

From 1984 it carried the local strain name Makurazaki No. 9 (枕崎9号) and moved into wider adaptation trials: four nationally funded regional-adaptation sites (Mie, Kyoto, Kochi, Kumamoto), one dedicated cold-damage evaluation site (Kagoshima, testing specifically for split-bark frost injury), and nine prefectural trial sites (Saitama, Shizuoka, Fukuoka, Saga, Nagasaki, Oita, Miyazaki, Kagoshima, Okinawa). Eleven breeders are credited across the full 1969–1990 programme — Yasuma Shun, Toyao Tadayuki, Matsushita Shigeru, Kayumi Jikkō, Takeda Yoshiyuki, Kondō Sadaaki, Yanase Yoshimitsu, Ikeda Namiko, Hachinohe Michio, Wada Mitsumasa and Nesumi Atsushi — the same list of names given both in the breeding team’s own 2006 retrospective paper and independently on the MAFF variety-registration record for it.

By 1989, results from the breeding site and the regional trial network showed that in warm and mild-temperate regions the cultivar was reliably early, high-yielding and good in sencha processing. It was named and registered as Cha Norin No. 40, “Saemidori,” in June 1990. A separate registration followed under the then Seeds and Seedlings Act (種苗法) — application filed 29 March 1990, granted as Registration No. 2881 on 19 November 1991, with rights held by the national research organisation for a standard 18-year term that expired on schedule in November 2009 (see conflicts for how this explains the recurring 1990-versus-1991 discrepancy in secondary sources).

Adoption was slow at first — Saemidori was registered in 1990, just as Yabukita’s own spread was peaking nationally and there was little appetite among growers for replanting. By the breeding team’s own account, cultivated area went from essentially nothing in the mid-1990s to 358 ha by 2002 (7th among all cultivars) and an estimated 600+ ha by 2005 (6th), concentrated in Kagoshima and expanding through the rest of Kyushu. First-flush prices by 2005 were running 2,000–3,000 yen per kg above Yabukita’s, at an average of 5,000–8,000 yen/kg. Saemidori is now treated as a de facto Kagoshima prefectural brand cultivar, and cultivation has continued to spread since — it sits at roughly 4% of national tea acreage today, the largest share of any cultivar bred after Yabukita itself.

Characteristics

Saemidori buds and reaches first-flush harvest about four days ahead of Yabukita at the Kagoshima breeding site — 19 March versus 23 March for budding, 18 April versus 22 April for harvest, in the breeding team’s own multi-year trial average. Cited more loosely elsewhere as “four days to about a week” early — a range NARO’s own cultivar handbook gives as four to seven days — and measured at 6.7 days early to budding at the Miyazaki breeding site of a separate, more recent multi-prefecture trial run for the related cultivar Haruto 34, whose own average across its national trial sites is a more modest 5.3 days. Growth habit is intermediate, vigour is about equal to or slightly stronger than Yabukita’s, and cutting propagation takes well.

Fresh-leaf yield at the breeding site clearly beat Yabukita across every flush in the original trial — 531 vs. 379 kg/10a in first flush, 297 vs. 189 kg/10a in second, 279 vs. 193 kg/10a in third — though the cultivar’s own formal Plant Variety Protection Act characteristic filing is more conservative, describing mature-tree yield as only “slightly high” rather than citing those figures directly; growers should treat the breeding-site numbers as an upper bound rather than a typical result.

Disease and cold resistance is a genuinely mixed picture, and the two most authoritative sources available — the breeding team’s own 2006 trial data and the formal Plant Variety Protection Act characteristic filing from 1990 — do not fully agree with each other. Anthracnose resistance reads as medium and better than Yabukita’s in the trial comparison, but “slightly weak” in absolute terms on the PVP filing. Ring spot disease (Pestalotiopsis longiseta) resistance is weak, on a par with Yabukita. Winter cold hardiness — resistance to red-wilt and to split-bark frost injury — is rated strong in the breeding team’s own trial, equal to or, in their own prose, better than Yabukita’s; the PVP filing rates split-bark resistance more moderately, as medium. Neither source calls it weak. What is real and specific is a late-frost exposure problem: because Saemidori’s shoots emerge several days earlier than Yabukita’s, they are more often caught by late-spring frosts that a later-budding cultivar would simply miss, and recovery from that particular kind of damage is reported as poor. That is a narrower and more specific claim than a blanket “cold-sensitive” reputation, and this record treats it that way. Reports of markedly lower seedling survival (commonly cited as roughly 73% against Yabukita’s 88%) could not be verified here; the most directly comparable trial data found instead puts national-average nursery survival for both cultivars at an equal 75%.

In the cup, Saemidori’s defining trait is amino acid content: 2.50% total free amino acids against Yabukita’s 1.78% in the breeding site’s own quality trials, alongside markedly lower catechins (10.14% against 13.00%), which together produce the cultivar’s characteristic umami richness and low astringency. Aroma reads as mild and refined rather than Yabukita’s grassier “fresh” note. Interestingly, the same trial scored Saemidori’s liquor colour slightly below Yabukita’s (7.7 vs. 8.5 out of 10) despite the cultivar’s name and reputation for vivid green — consistent with the practical processing note repeated across sources that standard steaming can leave the liquor with a faint yellowish or reddish cast, and that a deeper steam is often used to bring out the colour the name promises. It is registered and used chiefly for sencha, suits gyokuro and pan-fired (kamairicha) processing well, and has become an increasingly common matcha cultivar on the strength of its colour and smooth, low-astringency texture, though it does not carry an official tencha or matcha designation from its original registration.