岡山大学農学部Acta Medica Okayama2186-77551022013培養液中Ca濃度が根域制限栽培したトマト果実の 水溶性Ca濃度と尻腐れ果発生に及ぼす影響2128ENYuichiYoshidaAyaShingaiMitsuoOoyamaKenjiMurakamiTanjuroGotoThe rate of absorbed Ca to N was less than half of Enshi or Hoagland solution in tomato (Solanum lycopersicum Mill.) grown with restricted root zone volume in previous experiments. Tomato plants were grown in plastic pots containing 250 or 500ml of peat based medium with modified Enshi solutions containing 1, 2 or 4mM of Ca. The solutions were prepared by replacing a part of Ca(NO3)2・4H2O to NH4NO3. Although Ca concentration was higher than 2mM in drainage collected from plants supplied 1mM Ca solution, absorbed amount of Ca was very small and severe symptom of Ca deficiency was observed. Incidence of blossom-end rot (BER) increased with decrease in Ca concentration of the solution and yield decreased to 50% and 36% of 4mM control, in 2mM and 1mM plots, respectively. Among fractionated Ca in stem of lateral shoot, decrease in water-soluble fraction was remarkable compared to 1N NaCl- or 0.6N HCl-soluble fractions. Tomato plants were then grown with modified solutions containing 1~4mM of Ca and fractionated Ca was determined for distal half of fruits. With decrease in solution Ca, fruit Ca decreased in all fractions, and days to BER incidence after flowering also decreased. Significant relationship was found only between the water-soluble Ca concentration in fruit tissue and rate of BER incidence. Thus water-soluble Ca in tomato fruit may closely relate to BER incidence, and an efficient tool to estimate the potential risk of BER may possibly be developed by determining the Ca fraction in the stem of lateral shoots.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama2186-77551022013培養液濃度と施用量が高CO2濃度条件下で育てたイチゴ‘さがほのか’の生育・収量と果実品質に及ぼす影響1520ENDaichiInazumiYuichiYoshidaTanjuroGotoKenjiMurakamiThe effects of supplied amount and strength of nutrient solution were investigated for strawberry (Fragaria×ananassa Duch. cv. Saga-honoka) grown with peat bags in elevated CO2 environment (800-2500 ppm in the day time, November 4 to April 7). Three strengths (L : low-80%, M : standard-100% and H : high-120%) of nutrient solution (N : 8.85, P : 0.85, K : 3.90, Ca : 2.05, Mg : 0.93 mM ; half strength of Ohtsuka A solution) were compared. Around 20% of discharged rate (discharged/supplied amount of nutrient solution) was kept for these 3 plots and 30 to 40% of the rate was kept for additional plot of 80%-solution (L2) by altering the supplied amount of 80%-solution. As almost no nitrate could be detected in drainage of L, nutrient supply was probably insufficient throughout the experiment. Total amount of nitrogen supply was lower than the other 3 plots and leaf area was the smallest after December. Although there was no significant difference in yield and fruit quality, the rate of tip burn affected flowers was lowest in L2 and highest in H. Thus, around 30-40% of drainage rate and 50-60 mS・m−1 of drainage EC may be desirable target values for ‘Saga-honoka’ strawberry grown with peat based substrate.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama2186-77551012012閉鎖型植物工場における連続光の利用（第4報）連続光下における植物の生理学的変化ならびに障害誘発の概念4964ENNaokiHataMasaharuMasudaKenjiMurakamiAkioKobayashiPhysiological changes and concept of injury induction occurring under continuous light are comprehensively reviewed. Continuous light usually reduces photosynthetic rate, which may relate to changes in transpiration and leaf necrosis caused by reactive oxygen species. Other factors apart from photosynthesis may also affect leaf injuries occurring under continuous light. Continuous light sometimes increases carbohydrate and some secondary metabolite contents.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama2186-77551012012‘ファースト’雄性不稔突然変異体 (T -4) を種子親とした軟果皮中玉トマトF(1) 系統 (MS-II) の特性1924ENJunkoToyaMasaharuMasudaKenjiMurakamiBreeding for a soft pericarp in medium-sized tomato fruit was conducted by crossing the male sterile mutant (T-4) of the large-fruited 'First' and a small-fruited pure line with a soft pericarp (S). Pericarp characteristics of the F(1) hybrid (named MS-II) were compared with the parents and two similar medium-fruited tomato cultivars, 'Red ore' and 'Frutica'. Pericarp firmness in MS-II was lower as compared with that of both T-4 and S. Differences in pericarp firmness among MS-II, 'Red ore' and 'Frutica' were dependent on truss. In the first truss, MS-II developed fruits with a softer pericarp than 'Red ore', but with a firmer pericarp than 'Frutica'. In the second and third trusses, pericarp firmness of the fruit in MS-II tended to be lower than those of the other two cultivars. The thickness of the exocarp cuticle in MS-II was lower than that in 'Red ore', but was no different to that in 'Frutica'. Thus genotypic differences in pericarp firmness among MS-II, 'Red ore' and 'Frutica' seem to be derived from differences in the degree of cutin development in the epidermal perimeter. A thinner cuticle can explain pericarp softness in the fruits above the second truss in MS-II.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-0254 9812009大玉トマトの防根給水ひも栽培における生育途中の根域拡張と「ひも」適用が果実生産に及ぼす影響2329ENAyukiMorishigeMasaharuMasudaKenjiMurakamiThis study was conducted to investigate the possibility to use capillary wick system in large-fruited tomato production. The first experiment in the autumn-winter season of 2006 was carried out to investigate
the effects of the amount of substrate on growth and yield of tomato. Treatments involved growing large-fruited tomato in one box (2.8ℓ/plant) continuously, or adding substrate at flowering of the 7th truss in a 2nd box (5.6ℓ/plant). Fruit yield was higher when the root-zone was extended with double the substrate volume. The second experiment in spring-summer season of 2007 was aimed at improving growth and yield of tomato by extension of root-zone and addition of wick. Tomato plants were either grown in one box with one wick continuously, or with addition of substrate in a 2nd box at flowering of the 4th truss. Additionally, one more wick was inserted into 50% of the 2nd boxes. Half of the plants were grown in two boxes with one wick, and the other half with two wicks. Higher yield was obtained from the plants grown in two boxes with two wicks, suggesting that fruit yield was increased by increasing water transport through wick addition coupled with root-zone extension. Plant growth and fruit yield of large-fruited tomato was stable without blossom-end rot when root-zone was extended and half strength of Ohtsuka-A nutrient solution supplied through the capillary wick system. There was, however, a slight sign of physiological disorder at the leaf margins similar to potassium deficiency.No potential conflict of interest relevant to this article was reported.園芸学会Acta Medica Okayama0013-76267612007Partial Fertility Restoration as Affected by Night Temperature in a Season-dependent Male-sterile Mutant Tomato, Lycopersicon esculentum Mill4146ENMasaharuMasudaKenjiKatoKenjiMurakamiHiroshiNakamuraThis study was conducted to investigate the influence of night temperature on the restoration of fertility in a season-dependent male-sterile tomato mutant (T-4). Plants were grown in greenhouses, in which minimum and maximum temperatures were set at 10℃ and 28℃ by heating and ventilation, respectively. Flowers were hand-pollinated and the fruit-set, seed-set, and number of seeds were examined. The rate of fruit-set was high and did not differ much from October to February; almost all fruits formed in October had self-fertile seeds, but 80% of the fruits from November to February were parthenocarpic. The rate of fruit-set dropped from 70% in March to below 10% in May. During this period, most of the fruits were seeded, though fruit-set was low. The number of seeds per seeded fruit varied with the season, being as high as 50 seeds in October, 1-2 seeds per fruit between November and March, and 1-20 seeds per fruit between April and June. A low night temperature of 12℃ did not affect fruit-set but resulted in a better seed-set than a high night temperature of 18℃ in the greenhouse. Further, pollination of the plants in phytochambers also resulted in a better fruit- and seed-set at 12℃ than 24℃. In all cases, the influence of low temperature was more pronounced in autumn than in spring. Fruit-set was 70% at 12℃ and 46% at 24℃. Of these fruits, 50% at 12℃ and 10% at 24℃ were seeded. It was inferred that partial fertility restoration in T-4 can be achieved by manipulation of night temperatures. The female organ was shown to be normal, functional, and compatible with wild-type pollen. From these results, the potential of the male-sterile T-4 mutant for use in a two line hybrid-seed production system was apparent.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02548511996シソ科ハーブ類のカルス培養および植物体再分化2330ENSachikoMatsubaraMasatoInoKenjiMurakamiMayumiKamadaIzumiIshiharaEffective methods of callus culture of herbs were studied to establish basic techniques for cell fusion and gene engineering. Eight basil cultivars, five species of Perilla family and a sweet basil were used, and following results were obtained. 1: Effects of phytohormones on callus formation. Callus formed effectively from hypocotyls and cotyledons of sterile seedlings cultured on MS medium supplemented with 0.1mg/12,4-D and BA. Plantlets succeeded in regenerating from callus cultured on MS medium supplemented with 0.1mg/I NAA and BA, but callus formation on a similar medium was inferior to that on MS medium supplemented with 2,4-D and BA. Callus formed best on MS medium supplemented with 2ip, among other cytokinins, but only BA actually induced regeneration of plantlets from callus. 2: Effects of age and different organs of explants on callus formation. Callus with similar weight formed from hypocotyls of young seedlings about 1-3 weeks after germination. The heaviest callus formed from cotyledons, followed by hypocotyls and roots. 3: Callus formation and regeneration of adventitious buds in eight basil cultivars. Calli formed cotyledons of lettuce basil, Anise basil, lemon basil, bush basil, sweet basil, purple raffles basil, dasil opal basil and cinnamon basil, in descending orderof weight, on MS medium supplemented with 2,4-D and 2ip. Callus from lettuce basil was three times as heavy as that from cinnamon basil. Callus formed on MS medium supplemented NAA and BA from cotyledone of all cultivars, but adventitious buds regenerated only from sweet basil, dark opal basil and bush basil. 4: Callus formation from six Perilla herbs. Callus fromed from hypocotyls and cotyledons of sweet basil, red perilla, green perilla, lemon balm, peppermint and sweet majoram in descending order of weight.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02548411995ナスの葯培養によるカルス及び胚様体形成に及ぼす温度処理の影響1316ENKenjiTokumoKenjiMurakamiSachikoMatsubaraAnthers containing uninucleate microspores of eggplant cv.'Wase-Shinkuro' were cultured on MS supplemented with 0.02mg/1 2,4-D and kinetin,3% sucrose and 0.2% Gelrite with high and low temprerature treatments to increase number of haploids,in early August and September and on November 4,1992.Anthers plated were kept heated at 35℃ for 48h in early November,and callus and embryoid were formed from microspores.The frequency of anthers foming callus was as high as 28% in treated anthers,but 14% in non-treated ones.Embryoids were obtained only in treated anthers,and the frequency of anthers forming embryoid was 5.1%.On the other hand,low temprerature pretreatments at 4℃ for 0,5 or 10days to flower buds in summer season were ineffective for embryoid formation and inhibitory for callus formation with treatement for langer periods.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02548711998サトイモの品種‘八頭’のカルスおよびプロトプラストから再生した植物にみられた体細胞突然変異127132ENKenjiMurakamiJunkoNishiokaSachikoMatsubaraCharacters of plants regenerated from callus and protoplasts of taro (Colocasia esculenta Schott cv. Yatsugashira) were studied. Many green compact cell masses (calloid) and small number of yellow friable calli were formed by culturing segments of etiolated stem on Murashige and Skoog's (MS) medium supplemented with 30 g･liter-1 sucrose, 1 mg･liter-1 2,4-D and 2ip. Friable calli were proliferated by subculturing on the same fresh medium, and then they were suspension-cultured in a liquid medium. Protoplasts were isolated from these suspension cells. Shoots were regenerated from calloids, friable calli and protoplast derived-calli by transferring them to MS medium supplemented with 30 g･liter-1 sucrose, 0~2 mg ･liter-1 NAA and 2 mg･liter-1 BA or 2 ip. These shoots formed roots after being transferred to basal MS media. Plantlets were acclimatized and grown in the field. Original 'Yatsugashira' formed many shoots from the main corm, whereas 2 of 4 plants regenerated from calloid formed a single shoot from the main corm. Plants regenerated from friable calli were dwarf type and grew slowly. plants regenerated from both friable calli and protoplasts formed larger number of shoots than original 'Yatsugashira'.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02548711998長期間培養したサトイモのカルスから再生した植物の形態および収量123126ENKenjiMurakamiSachikoMatsubaraCharacters of plants regenerated from calli cultured for long period in taro (Colocasia esculenta Schott cv. Eguimo) were studied. Calli were obtained by culturing etiolated stem segments on Murashige and Skoog's (MS) medium supplemented with 30 g･liter-1 sucrose, 2 me･liter-1 NAA and 2 me･liter-1 2 ip. They were proliferated by subculturing on the same fresh medium for 10 or 15 months from initial planting. Plants regenerated after transferring them to hormone-free MS mediium. The yield of corms from plants regenerated from callus was lower than those of original 'Eguimo' (control). Leaf blade of plants regenerated from callus for 15 months (C-15) was more round than that of control plants. Corm shape of C-15 plants was more round than that of control plants.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02548711998Embryoid and Callus Formation from Microspores by Anther Culture from July to November in Pepper (Capsicum annuum L.)117122ENSachikoMatsubaraMasatoyoYamamotoMan HyunJoKenjiMurakamiEmbryoid and callus were regenerated from microspores of six cultivars of pepper (Capsisum annuum L.) by culture of anthers obtained from July to November. Anthers containing microspores at the uninucleate stage were planted in MS media supplemented with 0.004 mg ・liter-1 2,4-D, 0.1 mg ･liter-1 kinetin, 30 g ･ liter-1 sucrose and 2 g ･ liter-1 Gelrite, kept at 35℃ for 24h, and then incubated at 25℃ under 16h daylength for 40 days. Frequency of embryoid and callus formation varied with cultivars and period of initiation. Embryoid formation was more effective from September to October. A temperature of between 15 to 25℃ in the months of September and October was effective for higher embryoid formation. Even though embryoid and callus formation was obtained in all cultivars, the frequency of embryoid formation was higher in Cheongyang and Fushimi Amanaga, while callus formation was higher in Shishtou and California Wonder. Embryoid transferred to MS medium developed to plantlets, and were acclimatized. The number of chromosomes in the root tip cells was 12 (haploid) in 19 plants, 24 (diploid) in one plant and 20 to 23 (aneuploid) in 3 plants.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-0254 9612007サトイモ（Colocasia esculenta Schott) の組織中シュウ酸カルシウム結晶結晶密度における品種間差異2528ENKenjiMurakamiKyokoUeda The presence of calcium oxalate crystal in the petioles and corms is associated with acridity. In this study, varietal difference in the distribution of calcium oxalate crystal idioblasts in taro (Colocasia esculenta Schott) were investigated. Crystals of two forms were found: bundles of needle-like crystals (raphides) and aggregates of sand-like crystal (druses). Generally, the density of druse was higher than that of raphide, and there were few raphide idioblasts in the corm. The density of oxalate crystal was low in the edible petiole of cv. Yatsugashira and the edible corms of cvs. Yatsugashira, Akame-daikichi, Takenokoimo and Malaysia No. 1. There were few oxalate crystals in the cormels of all cultivars. There was no correlation between the density of oxalate crystal and the concentration of insoluble oxalate.
These results suggest that the edible quality is not related to the insoluble oxalate concentration but to the density of oxalate crystal.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02549512006Mutagenesis in Gynomonoecious Spinach (Spinacia oleracea L.) Plants and Selection of Low Oxalate Variants2128ENNaokiHataKenjiMurakamiYuichiYoshidaMasaharuMasudaAtsushiTanakaNaoyaShikazonoYoshihiroHaseThis study was conducted to evalute mutagenesis in gynomonoecious spinach (Spinacia oleracea L.) plants for inducing low oxalate variants.Gamma-ray and ion beams of 220 MeV12C5+ and 50MeV 4He2+ ware used as mutagen in seed irradiation. Optimum dosages for irradiation were determined to be about 100Gy, 15-20Gy and 150-200Gy in gamma-ray, 12C5+ and 4He2+, respectively. In M2 generation, there was one line segregating albino seedlings, one line segregating xantha seedlings and two lines segregating dioesious spinach. To save on labor and time for analysis, selection of low oxalate variants in M2generation was conducted by a two-step selebtion which consisted of the first snalysis of bulked leaves from 2 plants as one specimen followed by the second analysis of selected individual plants. In the first analysis of 813 specimens, we selected 13 specimens as low and 9 specimens as high in oxalate content. In the second analysus, there was consistency in the distribution of low and high oxalate content corresponding to the first screening, indicating that selebtion of low oxalate variants could be achived by this two-step selebtion with half the labor and time for analysis as compares to non-bulked method. There were no clear differences in distribution of oxalate content between M3progenies of plants selected as low or high oxalate content, suggesting that the low oxalate content in plants isolated in M2generation was not of a genetic origin. From these results, it seems to be necessary to explore a variant with obvious deviation from the bontinuous variation of oxalate content in the M 2 generation.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02549512006サトイモ（colocasia esculenta Schott)の体細胞雑種の形態的特性および球茎品質1319ENKenjiMurakamiSyougoObataHitoshiYanoKaeMitani Morphological character and quality of corm in somatic hybrid No.12 obtained by protoplast fusion between taro (Colocasia esulenta Schott) cvs. ‘Yatsugahira’and ‘Malaysisa No.4’were investigated.
The number of shoot and leaf was smaller than those of ‘Yatsugashira’and was larger than ‘Malaysia No.4’. The length of leaf blade and petiole were shoeter than the two parents. The number of corm was smaller than the two parents. Generally, the shape of top was comoact as compared the two parents.
The total weight of corms was about a half of that of ‘Yatsugashira’, and a thirs of that of ‘Malaysia No.4’. The weight of mother corm of somatic hybrid No.12 was 400-500g. The corm morphology of somatic hybrid No.12 was almost intermediate between the two parents. The upper surface of mother corm of somatic hybrid No.12 was smooth; it was much different from that of mother corm of ‘Yatsugashira’. Starch content of borm was similae to ‘Yatsugashira’and smaller than ‘Malaysia No.4’. Sugar and amino acid contents of somatic hybrid No.12 were higher than those of the two parents. Calcium oxalate content was to the parents.No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02548011992ナスの胚軸からの耐塩性カルスの選抜3136ENKenjiMurakamiSachikoMatsubaraナスの胚軸の切片を種々の濃度のNaClを添加した培地に植え付けて培養した.0.2% NaCl添加培地において,カルスの生体重は,NaCl無添加培地の2分の1になった(Fig.1).1.0% 以上のNaCl濃度では,カルスは全く形成されなかった.そこで,0.8% NaCl添加培地で形成したカルスを,その後のカルス選抜に用いた.0.8% NaCl添加培地で2年間継代培養すると,活発に増殖するカルスが得られた(これをC-0.8とする).さらに,0.8% NaCl添加培地で形成したカルスを1.0,1.2,1.4,1.6とNaCl濃度を上げた培地に順次継代し,1.6% NaCl添加培地でも生存するカルスを作出した(これをC-1.6とする).対照とするカルスには,NaClを含まない培地で2年間継代培養したものを用いた(これをC-0とする). カルスの色は,C-0は白色であったが,C-0.8およびC-1.6は緑色であった.カルスのかたさは,C-0.8はC-0よりやわらかく,C-1.6はC-0よりかたかった.カルスの乾物率は,C-0とC-0.8は差がなかったが,C-1.6は高かった(Table1).0.8% NaCl添加培地では,C-0の増殖は著しく抑制されたが,C-0.8およびC-1.6の増殖はわずかに抑制されたのみであった(Table2). カルスの耐塩性の安定性を調べるため,C-0.8およびC-1.6を60日間NaCl無添加培地に移殖し培養した後,0.8% および1.6% NaCl添加培地にそれぞれ戻した.60日間NaCl無添加培地で培養後も,C-0.8は耐塩性を示したが(Table3),C-1.6の耐塩性は失われた(Table4). 不定芽は,C-0.8を1.0mg/literBAを添加したNaCl無添加培地に移植すると再生した.本実験の結果,ナスのカルスを0.8% NaCl添加培地で継代培養することにより,耐塩性カルスが得られることが分かった。No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02547711991アスパラガス側芽培養でのアンシミドールによる発根及び多芽体形成915ENSachikoMatsubaraSeijiMasudaKenjiMurakamiKazuhisaTakahashiSatoshiIshikuraアスパラガス側芽培養での発根促進と多芽体形成のための培地条件を検討した.供試材料として‘メリーワシントン500W’の播種後15-20日令植物の側芽を用いた.側芽を5μM ancymidolと5% ショ糖添加MS培地で2月間培養したところ,生存個体の90% が発根した.一方,3.9～39μM ancymido1と3% ショ糖添加MS培地で2月間培養後に多芽体が形成した11.7μM ancymidolでは生存個体の70% と最も高率に形成し,それからは12.7本の苗条が伸長したが,そのうちの一部分は水浸状であった.正常な植物体は,0.5～10μM ancymidolと5% ショ糖を添加したMS培地で2月間培養することにより得られ,特に5～10μMancymidol添加により植え付け外植体の約70%が正常個体となった.また,5～50μM ancymidolと5% ショ糖を添加したMS培地で2月間培養すると多芽体の形成が見られ,それらをMS培地に移植することにより苗条の伸長が見られた。No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02547511990ニンニクのウイルス・フリー株の生産性及び花床培養による増殖913ENSachikoMatsubaraDzenChenMasaharuMasudaKenjiMurakamiニンニクの茎頂培養によるウィルスフリー株の育成を試み,フリー株と罹病株の球の生産性の比較を行った.またフリー株の増殖を目的とした花床培養を試みた.生産性の比較:茎頂培養により育成したウィルスフリー株からの球根と,罹病株からの球根を,圃場に植え付け翌年6月に掘り上げて球の収量を比較した.フリー株の球重は罹病株に比較して1.4倍,球数は1.2倍となった.抽台茎上の花床に形成された珠芽も多かった.花床培養:花床を8分割して培養したところ,NAAを添加したMS基本培地に植え付けた区で正常な苗条が再生し,特に0.1mg・l-1NAA添加区で苗条の再生数が多く,それらをホルモン無添加培地に移植することにより球となった.1花床から約40球が再生された。No potential conflict of interest relevant to this article was reported.岡山大学農学部Acta Medica Okayama0474-02549412005トマト‘ファースト’種子へのイオンビーム照射によって誘発された短節茎突然変異体の生育肥大特性と遺伝様式2529ENMasaharuMasudaToshihikoYuasaKenjiMurakamiTomato(Lycopersicon esculentum L.) cv. 'First' mutants with short internodes grew vigorously. The number of leaves slightly increased and the shape of the leaves was similar to wild type. In inflorescence morphology, the number of flowers increased and the length of peduncle and pedicel were shorter. In fruit characteristics, weight per fruit, total yield, sugar and acid contents were similar to wild type. But a lot of malformed fruit set was observed in the mutant line, due to the number of locules and short length of the peduncle and pedisel. The segregation ratio of the short internodes character fitted 3:1 of normal:short ,hence it was considered to be contralled by a single pair of recessive genes. Allelism with alresdy known dwart gene was examined by crossing with 'Alisa Craig', which had a symbolized dwart gene, br or bu. Thereby, it was revealed that bu and short internodes gene ware in the same gene locus. This mutant line has no negative effect on plant growth and fruit yield, but was unsuitable for use as fresh fruit by reason of malformed fruits. These results indicated the possibility of breeding of a new cultivar with bu gene derived from 'First'. Since the mutant with short internodes is derived from 'First', which is already a commercial variety with excellent characteristics, raising a new commercial variety with short internodes trait may not take a long time.No potential conflict of interest relevant to this article was reported.