A linear theory of dipole radiation from piezoelectric semiconductors in the presence of acoustic amplification is presented, which shows the possibility that the radiation is of observable magnitude. Two processes are considered in succession, the amplification of electronic polarization current and the dipole radiation therefrom. The threshold field curve for radiation is calculated for n-InSb at 77K.

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高辛味系統だけが報告されているキダチトウガラシ（Capsicum frutescens）において低辛味性の系統‘S3212’を見いだした．低辛味性の遺伝を解析するために，高辛味性の‘S3010’（C. chinense）との雑種を作出し，F₂ および BC₁ における辛味性の分離を調査した．分離比から低辛味性は劣性 1 遺伝子（cf）に支配されていると考えられた．これまでに報告されている辛味成分の生産を支配する C 遺伝子座との同座性を C 遺伝子座と連鎖する CAPS マーカー SCY-800 を用いて検定したところ，cf 遺伝子座は C 遺伝子座と異なることが明らかになった．288 のプライマーを用いて cf 遺伝子座と連鎖する RAPD マーカーを検索したが，cf 遺伝子座と密接に連鎖するバンドは検出できなかった．本研究で明らかにした cf 遺伝子は，辛味成分の遺伝学的解析および安定した低辛味品種の育成に有用である．

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Apocynum venetum LINN. is an important Chinese crude drug, and its sibling species A. pictum SCHRENK is a confusable herb which is similar to it. The purpose of this study is to develop DNA molecular markers to distinguish A. venetum from A. pictum through the combinative technologies of bulked segregate analysis (BSA) and randomly polymorphic DNA (RAPD). Two putative markers B08-407 and B03-1368 specific for A. venetum were identified and sequenced. Based on the sequence information, two pairs of primers were designed and synthesized for sequence characterized region (SCAR) markers. But only one primer pair, B03-1368, produced a clear SCAR band in all samples of A. venetum and not in A. pictum. This SCAR marker was found useful for rapid identification of A. venetum from A. pictum.

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Well above the threshold for acoustoelectric instability, the time-dependent Ginzburg-Landau equation governing the motion of a phonon system in the threshold region breaks down on account of the parametric generation of subharmonic phonons, and in some cases it gives rise to an undamped oscillatory behavior of the system. It is suggested that the tremendous fluctuation in the acoustoelectric current is a manifestation to this behavior.

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Panax ginseng is widely used as a Chinese medicine, but it takes a long time to reach harvest and to establish its qualified strains. In the course of searching high quality Panax ginseng, we found a useful random polymorphic DNA (RAPD) primer, which showed a 725 base pair band for a selected elite strain Aizu K-111 (now called Kaishusan) including its cultured tissues, while the other strains did not necessarily show this band. We sequenced the DNA fragment and designed primers to improve electrophoretic profiles, based on the sequence.

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We applied length polymorphism (LPM) of PCR- DNA fragments from the 16S ribosomal RNA gene (16S rDNA) to analyze bacterial communities in soil. The PCR (polymerase chain reaction) primers were designed to classify soil bacteria into three groups: 1) the α and δ subclasses of Proteobacteria, 2) the β and γ subclasses of Proteobacteria, and 3) the flexibacter and Gram- positive bacteria. Eight variable regions of 16S rDNA were analyzed, and as a result, region 1 of 16S rDNA was found to be effective for LPM analyses. Bacterial DNA was extracted directly from the soil samples, and the LPM patterns for the PCR- DNA fragments were obtained using a high- resolution gel. We observed substantial changes in the LPM patterns, which were attributed to the changes in the vegetation and to seasonal changes. These changes showed that the proposed technique can be applied for monitoring changes in bacterial communities.

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宮城県蔵王山系馬ノ神岳に遺存しているカラマツ(以下,ザオウカラマツ)と中部山岳地帯に広く分布しているカラマツ(Larix kaempfen;以下,ニホンカラマツ)を識別するためのDNA分子マーカーを開発した。ザオウカラマツおよびニホンカラマツのそれぞれに特異的に現れるRAPDフラグメントを単離し,そのSCAR化を行った。その結果,ニホンカラマツに高い特異性を示す3マーカーとザオウカラマツに高い特異性を示す2マーカーを得た。この5マーカーを同時に使用することにより,ザオウカラマツとニホンカラマツを識別(危険率:4.91×10^-7 )することが可能になった。この5マーカーのうち識別能の高い3マーカーを用いることにより,より容易に識別(危険率:2.45×10^-5 )ができる。

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カラマツ（ニホンカラマツ；Larix kaempferi）は中部山岳地帯を中心に分布ており、その天然分布地域から約300km離れた宮城県蔵王山系馬ノ神岳にはカラマツ（以下、ザオウカラマツとする）が１２個体存在している。ザオウカラマツは外部形態的にはグイマツに類似しており、他の地域のニホンカラマツとは遺伝的に異なっている。現在、ザオウカラマツの個体数の減少が報告されており、遺伝資源保存が求められている。本研究ではニホンカラマツとザオウカラマツの識別を確実に行うため、試料197個体（ザオウカラマツ15、ニホンカラマツ182）を用いてSCARマーカーの開発を試みた。RAPD分析で得られた13組のプライマー対のうち３組がザオウカラマツに特異的なSCARマーカーであったが、それらはどれも完全なものではなかった。しかし３個全てのSCARマーカーを使用することで判別が可能になることがわかった。これにより遺伝的に貴重なザオウカラマツの遺伝資源の現地保存を行う際に、ニホンカラマツの汚染個体の混入を防ぐことができると考えられる。

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For AFLP analysis of grapes, three different concentrations of restriction enzymes were examined to reduce artifact bands due to incomplete digestion or star activity of the restriction enzymes. Differences among band intensities were neglected, and all the detected bands were used in the analysis. A phenogram of 12 cultivars of Vitis vinifera, two cultivars of V.labrusca and two wild species, V.ficifolia var.lobata (V.thunbergii, Ebizuru) and V.coignetiae (Yamabudou) was obtained by UPGMA (unweighted pair group method arithmetic averages) based on the percentage of unshared AFLP bands of each sample pair, using four primer pairs. This phenogram revealed a clear separation of the tested species and proles with high bootstrap probabilities, except for the clusters with a longer phenetic distance in the Oriental cultivars of V.vinifera. The cluster of Occidental cultivars split into a cluster consisting of Cabernet Sauvignon and Cabernet franc, and another cluster consisting of Pinot noir, Pinot blanc, Chardonnay and Riesling. Among the Oriental cultivars, two Japanese cultivars, Koshu and Koshu-Sanjaku, formed a cluster. Thus, this phenogram agreed well with the classification based on morphological properties and geographical location.

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Random polymorphic DNAs (RAPDs) were identified in rice by amplification using single 10-mer primers of arbitrary sequence. The number of amplification products increased with increasing GC content of the primer in the range between 40% and 60% GC. Single-base substitutions of a primer altered amplification, providing new polymorphisms. The size of DNA was mostly between 0.5kbp and 2.2 kbp with the most common bands at 1.5 kbp. Sixteen rice accessions were assayed with 28 primers which generated 116 polymorphic DNAs or RAPDs. All accessions were uniquely distinguished by at least one RAPD and clustered into three distinct groups which corresponded to Japonica, Javanica and Indica. Japonica differed on average from Indica with 80.1 RAPDs and from Javanica with 30.8 RAPDs. It was, thus, demonstrated that RAPDs were useful polymorphisms in rice and superior to RFLPs for their technological simplicity. RAPDs would be good alternatives for the construction of a genetic map because of the higher frequencies of polymorphism detection.

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ブンタン［Citrus maxima （Burm.）Merr.］‘晩白柚’の半数体を誘導するために，軟 X 線照射花粉を受粉して着果と種子発育に及ぼす影響を調査するとともに，胚珠培養を行った．軟 X 線を照射した‘福原’スイートオレンジ［C. sinensis （L.）Osbeck］の花粉を‘晩白柚’に受粉すると，着果率はやや低下した．また，1 果実当たりの種子数は照射量の増加に伴い減少した．しかしながら，これらの交雑から得られた実生はすべて二倍体であった．一方，軟 X 線を照射した‘福原’スイートオレンジと‘土佐文旦’（C. maxima）花粉を受粉して胚珠培養を行うと，6 系統の半数性を示す胚様体が誘導された．その内，400 Gray 照射した‘土佐文旦’花粉を受粉後 40 日に胚珠培養した胚様体から染色体数 9 本を有する半数体植物が 1 個体得られ，RAPD および CAPS 解析によりこの半数体は‘晩白柚’由来であることが示された．

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高等学校学習指導要領の改訂により，高校生物では，多くの分子生物学的現象を扱うようになった．その中でも，PCR法は分子生物学研究の基盤技術であり，その原理の理解は，他の技術の理解や習得に不可欠である．しかし，教科書でのPCR法の説明では，プライマーはどのようなものか，鋳型DNAにどのように結合するかの説明が不十分であり，プライマーを両端として伸長される新生鎖がPCR法で生じる増幅領域となる理由を生徒が深く理解することができないと考えられる．

そこで，プライマーDNAが鋳型DNAに結合することを理解するのに必要な解説と図を含んだワークシートを作成した．フォワードプライマーとリバースプライマーのそれぞれが，鋳型DNAに結合する位置と，各プライマーDNAが結合する向きおよび新生鎖の伸長方向を学ぶ内容である．このワークシートを利用し，増幅されるDNA断片の大きさを測る実験を行うことと，増幅されるDNA断片の領域を遺伝子の塩基配列から探す課題とを併用した授業計画を立案した．授業後，65％の生徒がプライマーDNAにより増幅される鋳型DNAの領域を正しく答えることができた．作成したワークシートによる学習が，プライマーの働きを理解するのに有効であったためと考えられる．

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Twenty epidemiologically unrelated Listeria monocytogenes strains isolated from different animals, locations and on different dates in Japan were classified into 18 types by the random polymorphic DNA (RAPD) fingerprinting technique with four primers. Further, seven epidemiologically related L. monocytogenes strains isolated from raw milk and a bulk tank on a dairy farm represented the same RAPD type suggesting that they were all of the same origin. Therefore, RAPD-polymerase chain reaction (PCR) analysis, which is rapid, simple and inexpensive to perform, can be used in surveys as a convenient epidemiological technique.

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Products of disease resistance genes cloned from several plant species share structural motifs such as a nucleotide binding site (NBS) and leucine-rich repeats. The presence of conserved domains in resistance genes anabled the cloning of nunrerous additional resistance gene analogs from rice using a polymerase chain reaction (PCR) with degenerate oligonucleotide primers to the NBS motifs. Ten resistance gene analogs (RGAs) were from rice varieties Aichiasahi and Toride-1. The sequences coded open reading frames with additional sequences characteristic of NBSs. A hounology search through a database revealed significant similarities to known resistance genes. Southern blot analysis of eight rice varieties probed with RGAS demonstrated that most of them were single copy genes with diverse restriction fragment length polymorphisms (RFLPs). RFLPs Were observed between japonica and indica type rice in some RGAs and within bothjaponica and indica varieties. Some of their map positions were linked to known true resistance loci and some to field resistance (quantitative trait) Ioci. The transcription for RGAs could be detected by RT-PCR; however, their transcription levels were extremely low and varied with the variety.

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