@article{oai:repository.naro.go.jp:00003817,
 author = {齋藤, 寿広 and SAITO, Toshihiro and 澤村, 豊 and SAWAMURA, Yutaka and 髙田, 教臣 and TAKADA, Norio and 壽, 和夫 and KOTOBUKI, Kazuo and 西尾, 聡悟 and NISHIO, Sogo and 寺井, 理治 and TERAI, Osamu and 平林, 利郎 and HIRABAYASHI, Toshiro and 佐藤, 明彦 and SATO, Akihiko and 正田, 守幸 and SHODA, Moriyuki and 阿部, 和幸 and ABE, Kazuyuki and 加藤, 秀憲 and KATO, Hidenori and 西端, 豊英 and NISHIBATA, Toyohide and 佐藤, 義彦 and SATO, Yoshihiko and 樫村, 芳記 and KASHIMURA, Yoshiki and 尾上, 典之 and ONOUE, Noriyuki and 鈴木, 勝征 and SUZUKI, Katsuyuki and 内田, 誠 and UCHIDA, Makoto and 木原, 武士 and KIHARA, Takeshi},
 journal = {農研機構研究報告, Journal of the NARO Research and Development},
 month = {Jul},
 note = {‘Hatsumaru’ is a new, very-early maturing cultivar of Japanese pear (Pyrus pyrifolia Nakai) that was released in 2014 by the Institute of Fruit Tree Science, NARO. The cultivar was developed from a cross between ‘Chikusui’ and Tsukuba 43 in 1993, selected as a promising tree in 2006, and subjected to the eighth national trial as Nashi Tsukuba 54 from 2007, at 38 experimental stations in 37 prefectures throughout Japan. The cultivar was released as ‘Hatsumaru’ in 2014 and was registered under the Plant Variety Protection and Seed Act of Japan on June 19, 2015 (Registration No. 24374). ‘Hatsumaru’ trees are medium to moderately vigorous. They produced medium to moderately high number of shoots, few to medium number of fruit spurs, and medium number of axillary flower buds in the national trial. Flowering time was approximately April 15, three days earlier than that of ‘Chikusui’ and ‘Kosui’, and the harvest time was approximately July 30, which was one week earlier than that of ‘Chikusui’ and three weeks earlier than that of ‘Kosui’. ‘Hatsumaru’ fruits ripened until the first half of August, when the demand for Japanese pear peaks in consumer areas and the favorable sales are possible, in most of the pear-producing areas in Japan in the national trial. The cultivar was resistant to black spot and there was no serious problem of diseases and insect pests under standard spraying program. ‘Hatsumaru’ is cross compatible with other leading cultivars as its S-genotype is S1S4. The fruit shape of ‘Hatsumaru’ is oblate to round. Fruit weight averaged 296 g in the national trial, smaller than that of　‘Chikusui’ and ‘Kosui’. The flesh firmness of ‘Hatsumaru’ was 4.1 lbs, softer than that of ‘Chikusui’ and ‘Kosui’. The soluble solid content was, on an average, 12.4%, which was lower than that of ‘Chikusui’ and ‘Kosui’. The pH of fruit juice, on an average, was 5.1, which was comparable with that of ‘Chikusui’ and lower than that of ‘Kosui’. The eating quality of ‘Hatsumaru’ was comparable with ‘Chikusui’ and ‘Kosui’. The shelf-life of ‘Hatsumaru' was around 5 days, a little shorter than that of ‘Kosui’. The dead lateral flower bud rate of ‘Hatsumaru’ in Kumamoto Prefecture was apparently higher than that of ‘Kosui’. ‘Hatsumaru’ is expected to be extensively cultivated as a very-early ripening cultivar in Japan, especially in Kanto and South Tohoku region., ‘はつまる’は，1993年に‘筑水’と筑波43号を交雑し，育成した実生から選抜した極早生のニホンナシ品種である．2007年からナシ第８回系統適応性検定試験に供試し，2014年2月の果樹系統適応性・特性検定試験成績検討会で新品種候補にふさわしいとの合意が得られ，2015年６月19日に第24374号として種苗法に基づき品種登録された．樹勢は中～やや強く，枝梢の発生は中～やや多い．短果枝の着生は中～やや少なく，えき花芽の着生は中程度である．開花期は4月中旬で‘筑水’，‘幸水’より3日程度早い．交雑和合性を支配するS遺伝子型はS1S4で，主要品種と和合性を示す．若木の収量は‘筑水’と同程度で，‘幸水’より少ない．収穫期は7月下旬で，‘筑水’より1週間程度，‘幸水’より3週間程度早い．ニホンナシ主要産地の大部分の地域で，ニホンナシ果実の需要が高まる旧盆前の収穫が可能である．黒斑病抵抗性で，黒星病にはり病性である．果実は円～扁円形を呈し，大きさは300g程度で‘筑水’，‘幸水’より小さい．果実品質について，果肉は軟らかくち密であり，硬度は4.1ポンドで対照品種より軟らかく,糖度は12.4％で対照品種より低く,pHは5.1程度で‘幸水’より低いが酸味はほとんど感じない．果実の日持ち性は5日程度で‘幸水’よりやや短い．各地で花芽の枯死が観察され，特に西南暖地での発生が多い．消費地で果実の需要が高まり，有利販売が可能な8月上旬までの収穫が可能であり，‘幸水’の旧盆前収穫が困難な東日本での普及が期待される．},
 pages = {41--49},
 title = {ニホンナシ新品種‘はつまる’},
 volume = {4},
 year = {2020},
 yomi = {サイトウ, トシヒロ and サワムラ, ユタカ and タカダ, ノリオ and コトブキ, カズオ and ニシオ, ソウゴ and テライ, オサム and ヒラバヤシ, トシロウ and サトウ, アキヒコ and ショウダ, モリユキ and アベ, カズユキ and カトウ, ヒデノリ and ニシバタ, トヨヒデ and サトウ, ヨシヒコ and カシムラ, ヨシキ and オノウエ, ノリユキ and スズキ, カツユキ and ウチダ, マコト and キハラ, タケシ}
}