ブドウ’巨峰’自根樹の根と母枝の耐寒性

Root and cane of own-root 'Kyoho' grapevunes were tested for winter cold resistance using EC(electrical conductivity) and TTC(triphenyl tetrazorium chloride) tests, as well as anatomical observations and survival tests. Vines were exposed to various subzero temperatures for various durations in two separate experimental trials, one in December, one in January. The EC and TTC reduction of small roots (φ3-5mm)were slightly affected. After exposure to -4℃ for only 12 hours the EC markedly increased and TTC reduction decreased in both small and large roots. Cells of cortex and ray tissues in the root were ruptured. New root growth on root cuttings taken from the vine previously exposed to -4℃ was servely inhibited. These results indicate that 'Kyoho' roots cannot resist temperatures of -4℃ or lower even for a single night during winter. On the other hand, 'Kyoho' canes survived -15℃ even for 24 days. However, exposure to -20℃ or -30℃ greatly affected the EC and TTC reduction in the cane and inhibited bud bursting entirely.冬季が寒冷な地域で’巨峰’の地域制限栽培を行うためには、根の耐寒性限界を知ることが必要である。そこで、’巨峰’の2年生挿し木個体を12月及び1月に種々の低温で処理し、根のEC及びTTCテスト、組織形態の観察、根挿しによる発根テストなどを行った。その結果、-3.0℃で24日間処理しても直径1～2mmの細根ではEC,TTC還元力とも変化がないが、直径3～5mmの大根ではやや変化した。-4℃で12時間処理すると、細根、大根のECとTTC還元力が大きく変化し、根挿しの発根も抑制された。また、根の皮層と放射組織の細胞が破壊され、空洞が生じた。処理した個体の翌春の生長も著しく不良であった。したがって、自根の’巨峰’樹の根は－4℃以下の低温に１晩でも遭遇すると危険である。一方、母枝は－15℃で24日間処理してもECやTTC還元力の変化はなく、挿し木した後の発根も正常であった。しかし、－20℃処理ではECとTTC還元力が大きく変化し、発芽も完全に抑制された

Aromatic Components of Several Table Grapes Produced in Japan

生食用の雑種4品種('キャンベル・アーリー','巨峰','竜宝','マスカット・ベーリーA')とV.viniferaの'ネオマスカッﾄ'の香気成分を調査した.また,果汁中の揮発性成分をLiquid-liquid extraction法,Solvent extraction法,Head-space analysis法の3種類の方法で抽出し,その結果を比較検討した. 'ネオマスカット'からはV.viniferaの代表的な香気成分であるリナール,α-テルピネオール,シトロネロール,ネロール,ゲラニオールが検出された.とくにゲラニオールが量的に多かった.雑種4品種からは多量の2-フェニルエチルアルコールが検出された.しかしV.labruscaに特徴的に含まれるとされるアントラニル酸メチルは検出されなかった. Liquid-liquid extraction法, Solvent extraction法の2つの抽出方法では,検出成分の種類は変わらなかったが,Solvent extraction法の方が揮発性成分が量的に多く検出された. Head-space analysis 法では得られた揮発性成分が少なく固定もできなかった

ブドウ’マスカット・オブ・アレキサンドリア’、’ネオ・マスカット’の無核化と果粒サイズに及ぼす抗生物質の処理時期の影響

A study on the effects of the application date of antibiotic on seedlessness and berry size was conduced using 'Muscut of Alexandria'(MOA) and 'Neo Muscut'(NM) grapevines. Two antibiotics were used as seedlessness inducer,streptomycin(SM) and spectinomycine(SE) applied in the concentoration of 200mg/L by dippinng the clusters.The tested of dates of application were 6 and 3 days before full bloom, at full bloom (50% anthesis),and 5days after full bloom.The 3-days before full bloom application gave the highest percentage of seedless berry within each antibiotic in both cultivars.Application after than 3days before full bloon increased production of empty-seeded berries, though the later application was able to increase the berry size and berry weight.'マスカット・オブ・アレキサンドリア’と’ネオ・マスカット’について、無核化のために行う抗生物質処理の時期がその効果と果粒の肥大に及ぼす影響を調査した。無核化剤としてストレプトマイシンとスペクチノマイシンを用い、満開日（小花の50％が開花）とその6,3日前、および5日後に200ｍｇ/MLで果房の浸漬処理を行った。両品種とも、3日前に各抗生物質を処理すると無核化率が最も高かった。それより遅い処理では果粒サイズは大きかったが、空洞種子（empty seed) を含む果粒が多く着生した

岡山で生産される白色桃の果実サイズ別の果皮色と果汁成分

Skin color and juice constituents in large(L), medium(M), nad small(S) fruits of four peach cultivars, Hashiba-hakuho(early maturing), were analyzed to elucidate the effect of fruit size on the quality. The fruits containing higher soluble solids than 12°Brix were samled at a commercial packing-house located in southen Okayama. They were stored at 25℃ until fully ripened. The skin color on the cheeks (yellowish) was dark in S fruits of Hashiba-hakuto and Hakurei, respectively, compared to the fruits of other sizes. The sucrose + fructose content in juice, the major source of the sweetness, was higher in S and M fruits in Hakuho, Shimisu-hakuto, and Hakurei, while the malic+citric acid content, the major sour constituent, was lower in L fruits in those cultivars, although no significant difference was found in Hashiba-hakuho. Asparagine, the biggest amino acid fraction and thought to deteriorate the fruit taste at high levels, was higher in L fruits tahn in S fruits in Hashiba-hakuho and Hakuho. The content in Shimizu-hakuto and Hakurei fruits was generally low and not affected by fruit size. The content of γ-decalactone, the major peachy aromatic substance, was higher in L fruits in Hashiba-hakuto, in M fruits in Hakuho and Shimizu-hakuto, and in S fruits in Hakurei, than in those of other sizes. Sensory tests revealed that the L fruits of Hakuho and S fruits of Hakurei were poor in flavor. These results suggest that the larger fruits of Hakuho, Shimizu-kakuto, and Hakurei, the representative white peach fruits in Okayama, have rather falatter tastes than medium size fruits because of their lower sweetness and sourness and weaker aroma, as well as poorer texture.岡山市一宮のモモの選果場に出荷された有袋栽培の‘橋場白鳳’（早生），‘白鳳’（早中生），‘清水白桃’（中生）および‘白麗’（晩生）から，３段階のサイズ（Ｌ，Ｍ，Ｓ）の果実を入手し，完熟状態（手で皮が剥ける）に達するまで25℃の室温においた．それらの果実について，果皮色と果汁成分の分析と果肉の食味テストを行い，果実のサイズによる品質の相違を検討した．‘橋場白鳳’では，Ｓ果実は地色が暗く，‘清水白桃’のＬ果実は着色が濃いが色調が暗く，‘白麗’のＬ果実は着色が薄くて黄色が強く，いずれも外観が劣った．果汁中の主要な甘味成分であるスクロース＋フルクトース含量は，‘白鳳’，‘清水白桃’および‘白麗’ではＳまたはＬ果実で高く，酸味成分のリンゴ酸＋クエン酸含量は，それら３品種のＬ果実で最も低かった．‘橋場白鳳’では果実サイズによる糖・酸含量の有意な差がなかった．果実に苦みを与えるアスパラギン含量は，‘橋場白鳳’と‘白鳳’ではＬ果実で高かったが，‘清水白桃’と‘白麗’ではどのサイズでも含量が低かった．モモ香の主成分であるγ-decalactoneは，‘橋場白鳳’ではＬ果実で高かったが，‘白鳳’と‘清水白桃’ではＭ果実で，‘白麗’ではＳ果実で高かった．官能テストの結果，‘白鳳’のＬ果実と‘白麗’のＳ果実は食味が劣った．これらの結果から，岡山の「白桃」を代表する‘白鳳’，‘清水白桃’，‘白麗’の大果は，中程度の大きさの果実より甘味と酸味が低く，アロマが弱いなど，食味が薄く，肉質も劣ると考えられる

耐乾・耐湿性に関するヤマブドウ（Vitis colignetiae Pilliat）と生食用ブドウ品種の比較

Excess-water and drought tolerance of Vitis coignetiae grapevines were compared against 2 V. vinifera cultivars, Muscat of Alexandria and Rizamat; and 2 hydrids (V. vinifera × V. labrusca), Delaware and Kyoho. Three-year-old cutting vines of each, planted in root zone restricted beds in a plastic house, were tested under water logged and irrigation-withheld conditions starting from early and mid July, respectively. Control vines were irrigated at pF 2.2 of soil water tension. Effects of water logging were firstly observed in V. coignetiae vines where the basal leaves turned dark red after 12 days, and then abscised after 3 weeks. Under 2 weeks of water logged conditions, net assimilation rate (NAR) of the primary leaves decreased signficantly in V. coignetiae and the hybrid cultivars, Kyoho leaves turned yellow 3 weeks after the onset of the treatment and then dried out 4 weeks later. Leaves of Rizamat, Delaware, and Muscut of Alexandria vines exhibited a slight color fading or leaf curling after 4 weeks of irrigation withholding, but these symptoms did not extend thereafter. Leaf NAR and transpiration rate decreased significantly in all tested vines after 10 days of irrigation withholding, though the decrease was rapid in Kyoho vines. These results indicate that V. coignetiae vines have a lower tolerance for water logging than other ciltivars, whereas they have moderate drought tolerance

Characterization of DNA polymerase β from Danio rerio by overexpression in E. coli using the in vivo/in vitro compatible pIVEX plasmid

<p>Abstract</p> <p>Background</p> <p>Eukaryotic DNA polymerase β (pol β), the polymerase thought to be responsible for DNA repair synthesis, has been extensively characterized in rats and humans. However, pol β has not been purified or enzymatically characterized from the model fish species <it>Danio rerio </it>(zebrafish). We used the <it>in vitro</it>/<it>in vivo </it>dual expression system plasmid, pIVEX, to express <it>Danio rerio </it>pol β (<it>Danio </it>pol β) for biochemical characterization.</p> <p>Results</p> <p><it>Danio </it>pol β encoded by the <it>in vitro</it>/<it>in vivo</it>-compatible pIVEX plasmid was expressed in <it>E. coli </it>BL21(DE3), BL21(DE3)pLysS, and KRX, and <it>in vitro </it>as a C-terminal His-tagged protein. <it>Danio </it>pol β expressed <it>in vitro </it>was subject to proteolysis; therefore, bacterial overexpression was used to produce the protein for kinetic analyses. KRX cells were preferred because of their reduced propensity for leaky expression of pol β. The cDNA of <it>Danio rerio </it>pol β encodes a protein of 337 amino acids, which is 2-3 amino acids longer than other pol β proteins, and contains a P63D amino acid substitution, unlike mammalian pol βs. This substitution lies in a hairpin sequence within an 8-kDa domain, likely to be important in DNA binding. We performed extensive biochemical characterization of <it>Danio </it>pol β in comparison with rat pol β, which revealed its sensitivity to metal ion activators (Mn²⁺and Mg²⁺), its optimum salt concentration (10 mM KCl and 50 mM NaCl), alkaline pH optimum (pH 9.0), and low temperature optimum (30°C). Substituting Mn²⁺for Mg²⁺resulted in 8.6-fold higher catalytic efficiency (<it>k</it>_cat/<it>K</it>_m).</p> <p>Conclusions</p> <p>Our characterization of pol β from a model fish organism contributes to the study of the function and evolution of DNA polymerases, which are emerging as important cellular targets for chemical intervention in the development of anticancer agents.</p