The current study aimed to create an electrostatic window screen to keep stable flies and houseflies out of cattle barns. The screen comprised three identical framed metal nets arranged in parallel at specific intervals. The central net was connected to a negative-voltage generator to impart a negative charge, while the other two nets were grounded and placed on either side of the charged net. This configuration generated a corona-discharging electric field between the nets. The electric field produced negative ions and ozone around the negatively charged net, deterring houseflies from entering. Additionally, the screen emitted sparks via arc discharge to repel stable flies that did not exhibit avoidance behavior. The spark irradiation was intense enough to swiftly propel flies backward upon entering the electric field, ultimately leading to their demise. In summary, the device functioned as a corona-discharging screen to repel houseflies and as an arc-discharging screen to eliminate stable flies through spark irradiation. This study provides an experimental foundation for the development of an innovative device to manage undesirable flies in cattle barns.

This study developed an unattended electric weeder (UEW) to control floor weeds in an orchard greenhouse. The UEW was a motor-driven dolly equipped with a spark exposer. The spark exposer was constructed by applying an alternating voltage (10 kV) to a conductor net (expanded metal net). The charged conductor net (C-CN) discharged into the surrounding space. Wild oat and white clover were used as test weed species. Weed seedlings growing on the floor were grounded by the biological conductor and were subjected to a spark from the C-CN when they reached the discharge space. The spark-exposed seedlings were singed and shrunk instantaneously. In the present experiment, the UEW was remotely controlled to move on the soil-cover metal nets, which were laid on the floor to make a flat surface, in a stop-and-go manner, and to eject a spark to the weed seedlings that emerged from the floor. All of the mono- and dicotyledonous weed seedlings, which had been artificially sown on the floor, were completely eradicated using this method. Thus, this study provides an experimental basis for developing an unattended technique for controlling floor weeds in an orchard greenhouse.

In this study, we evaluated the effectiveness of hyperparasitic fungi in controlling powdery mildew (PM). In a greenhouse, we spray-inoculated single colonies of the melon PM-causing fungus Podosphaera xanthii strain KMP-6N at three different fungal developmental stages (i.e., 5, 10, and 15 days old) with spores of the hyperparasitic fungus Ampelomyces sp. strain Xs-q. After spray inoculation, we collected and counted KMP-6N conidia produced as asexual progeny from PM colonies using an electrostatic rotational spore collector. Collector insulator films were replaced at 24 h intervals until KMP-6N ceased to release additional progeny conidia. Conidial releases from each of the single Xs-q-inoculated KMP-6N colonies gradually reduced, then stopped within ca. 4 and 8 days of the first treatment in 5- and 10-day-old KMP-6N colonies, and within ca. 20 days of the second spray treatment in 15-day-old KMP-6N colonies, respectively. The total numbers of asexual progeny conidia collected from single 5-, 10-, and 15-day-old colonies were ca. 156, 1167, and 44,866, respectively. After electrostatic spore collection, conidiophores in Xs-q-uninoculated KMP-6N colonies appeared normal, whereas almost all conidiophores in 5- and 10-day-old Xs-q-inoculated KMP-6N colonies were completely deformed or collapsed due to the infection of the hyperparasitic fungus. This is the first study to apply electrostatic and digital microscopic techniques to clarify the impact of fungal hyperparasitism on mycohost survival, and, in particular, to assess quantitatively and visually the suppression of conidial release from any PM colonies infected with Ampelomyces.

A simple electrostatic apparatus that generates an arc discharge was devised to control adult houseflies emerging from a soil bed in a greenhouse. Adult houseflies emerging from a soil bed in a greenhouse are a potential vector of pathogenic Escherichia coli O157, carried by animal manure used for soil fertilization. A simple electrostatic apparatus that generates an arc discharge was devised to control these houseflies. The apparatus consisted of two identical metal nets; one was linked to a negative-voltage generator to create a negatively charged metal net (NC-MN), and the other was linked to a grounded line to create a grounded metal net (G-MN). A square insulator frame was placed between the two nets, separating them by 6 mm, and a plastic grating with multiple cells was placed beneath the G-MN to provide a climbing path (54 mm in height) to the arcing sites of the apparatus for adult houseflies emerging on the soil surface. Houseflies that climbed up the wall of the grating and reached the arcing zone were subjected to arc-discharge exposure from the NC-MN and thrown down onto the soil by the impact of the arcing. The impact was destructive enough to kill the houseflies. The structure of this apparatus is very safe and simple, enabling ordinary greenhouse workers to fabricate or improve it according to their own requirements. This study developed a simple and safe tool that provides a physical method to manage houseflies.

Powdery mildew fungi produce progeny conidia on conidiophores, and promote the spread of powdery mildew diseases by dispersal of the conidia from conidiophores in the natural environment. To gain insights and devise strategies for preventing the spread of powdery mildew infection, it is important to clarify the ecological mechanism of conidial dispersal from conidiophores. In this study, all of the progeny conidia released from single colonies of strawberry powdery mildew fungus (Podosphaera aphanis (Wallroth) U. Braun and S. Takamatsu var. aphanis KSP-7N) on true leaves of living strawberry plants (Fragaria × ananassa Duchesne ex Rozier cv. Sagahonoka) were consecutively collected over the lifetime of the colony with an electrostatic rotational spore collector (insulator drum) under greenhouse conditions, and counted under a high-fidelity digital microscope. The insulator drum consisted of a round plastic container, copper film, thin and transparent collector film, electrostatic voltage generator, and timer mechanism. When negative charge was supplied from the voltage generator to the copper film, the collector film created an attractive force to trap conidia. The electrostatically activated collector film successfully attracted progeny conidia released from the colony. Experiment was carried out at just one colony on one leaf for each month (in February, May, July, October, November, and December in 2021), respectively. Each collector film was exchanged for a new collector film at 24 h intervals until KSP-7N ceased to release progeny conidia from single colonies. Collection experiments were carried out to estimate the total number of conidia released from a single KSP-7N colony over a 35–45-day period after inoculation. During the fungal lifetime, KSP-7N released an average of 6.7 × 104 conidia from each of the single colonies at approximately 816 h. In addition, conidial release from KSP-7N colonies was largely affected by the light intensity and day length throughout a year; the number of conidia released from single KSP-7N colonies in night-time was clearly smaller than that in daytime, and the time of conidial release from single KSP-7N colonies was shorter by approximately 2 to 4 h in autumn and winter than in spring and summer. The ecological characteristics related to conidial releases from KSP-7N colonies will be helpful information for us to successfully suppress the spread of strawberry powdery mildews onto host plants under greenhouse conditions.

An unattended pest control system was developed to eliminate whiteflies (Bemisia tabaci) that settled on greenhouse tomato plants. The system exploited the whitefly’s habit of flying up from a plant that was mechanically tapped and then heading toward yellow objects. Remote-controlled dollies with arms that tapped plants and yellow-colored double-charged dipolar electric field screens (YDD-EFSs) (oppositely electrified transparent insulator tubes filled with yellow-colored water) attracted and trapped the whiteflies. The whiteflies flew up when the plants were mechanically tapped with the dolly’s arms during reciprocating movements and were subsequently trapped by YDD-EFSs that were automatically translocated to the target plants. The system was applied to rows of whitefly-infested tomato plants. Almost all whiteflies transferred to plants were successfully recovered by two dollies moving on either side of the plants, approaching all plants individually (via programmed movement). In summary, we present an efficient unattended method for controlling whiteflies on tomato plants in greenhouses.

Electrostatic devices generating an electric field (EF) are promising tools for greenhouse tomato cultivation. In these devices, an EF is generated in the space surrounding an insulated conductor (IC) that is charged by a voltage generator. Thus, a physical force is exerted on any insect that enters the EF, as a negatively charged IC (NC-IC) pushes a negative charge (free electrons) out of the insect body. The insect is polarized positively to be attracted to the NC-IC, and a grounded metal net (G-MN) repels the insect. This dual function of the apparatus (insect capture and repulsion) is the core of the electrostatic pest-exclusion strategy. In this study, we applied various innovative EF-based devices to evaluate their efficacy in greenhouse tomato cultivation. Our objective was to determine the optimal apparatus for simple, inexpensive construction by greenhouse workers. The results of this study will contribute to the development of sustainable pest-management protocols in greenhouse horticulture.

Type I trichomes of tomato leaves (Solanum lycopersicum Mill. cv. Moneymaker), as outgrowths of the plant epidermis, are suitable for monitoring infection processes of powdery mildew species using a high-fidelity digital microscope (DM) without fungal staining. On the trichomes, tomato powdery mildew (Pseudoidium neolycopersici L. Kiss) isolate KTP-03 produced a maximum of four vigorously elongated hyphae per conidium, which stopped growth approximately 12 days after inoculation. Single trichome cells, invaded by fungal hyphae at various fungal infection stages during the 12-day period after the inoculation of single conidia, were cut at the bases and directly collected with small precision scissors (i.e., microscissors) held by the manipulator under a DM. Subsequently, suc-polymerase chain reaction (PCR) (reverse transcription (RT)-PCR followed by nested (N)-PCR) was conducted to explore gene expression in the infected trichome. We selected intron-containing genes from tomatoes and powdery mildew fungi for the detection of constitutive gene transcripts, namely plasma membrane H+-ATPase (LHA2) and β-tubulin 2 (TUB2) genes. In suc-PCR, a single band from spliced mRNAs of both LHA2 and TUB2 genes were detected, suggesting that both genes were successfully transcribed in single KTP-03-infected trichomes. With combined primers for both LHA2 and TUB2 (multiplex RT-PCR/N-PCR), two bands were detected through the amplification of intron-spliced mRNAs of both genes. Therefore, our single-trichome cell PCR amplification method is effective for detecting the expression patterns of genes from both tomato and powdery mildew fungus. Combinations of digital microscopy, microscissors, and multiplex RT-PCR/N-PCR amplification techniques will be useful for simultaneously analysing the molecular interactions between plants and powdery mildew fungi at the level of single tomato leaf trichome cells. Also, this employed technique will be of benefit in other plant species and crops, possessing leaf trichome cells, to elucidate the molecular interactions between plants and pathogens.

Powdery mildew fungi infect plant leaves, reducing the yield of infected melon plants. Therefore, an eco-friendly method of controlling powdery mildew in melon plants needs to be developed. A previous study described how the morphological characteristics of the conidiophores of the melon powdery mildew fungus Podosphaera xanthii Pollacci (designated KMP-6N) grown under greenhouse (natural) conditions and red light-emitting diode (LED) irradiation differed from those grown under growth chamber conditions and blue LED irradiation. In the present study, conidiophores with unconstricted conidia under blue light were collected and inoculated onto host leaves through micromanipulation; the unconstricted conidia germinated and infected the leaves, producing vigorously elongated hyphae. The number of conidia collected, the initial times of conidial release from single colonies, and the number of conidia remaining in chains on conidiophores were examined with electrostatic techniques. Under red light, the number of collected conidia gradually increased with the light irradiation period. The initial conidial release occurred between 2 to 4 h; the number of conidia remaining on the conidiophores gradually decreased and, eventually, the conidiophore lengths became shorter. In contrast, under blue light, few conidia were collected at any given time; the number of conidia on the conidiophores gradually increased and, eventually, the conidiophore lengths became longer. Next, the effects of red and blue light on the spread of powdery mildew infection by placing a KMP-6N-infected melon seedling at the centre of a tray containing healthy melon seedlings were examined. Almost all healthy seedlings caused powdery mildew symptoms at ca. 21 days after red light irradiation, whereas only healthy seedlings near the infected seedlings showed symptoms after blue light irradiation. Thus, the spread of melon powdery mildew infection clearly differed between red and blue light irradiation. This is the first report describing the effects of red and blue light on the spread of P. xanthii infection from a single infected seedling to healthy host seedlings; their results provide insight into the ecological mechanisms of powdery mildew conidial scatter from conidiophores.

We developed an arc discharge exposer (ADE) that kills rice weevils nesting in dried rice. The ADE features multiple identical metal plates, half of these are linked to a voltage generator and the others are grounded. The plates were arrayed in parallel and an electric field formed between them. Any insect entering the field was arced from the negatively charged plate and killed. The ADE was placed on a vessel containing pest-infested rice grains; the insects were lured out of the grains by mechanically vibrating the vessel. When rice grains move, insects tend to climb upward, thus, the weevils were effectively removed. Our electrostatic apparatus is easy to construct and could be used to control pests in stored rice.

The purpose of this study was to develop a simple electrostatic apparatus to precipitate virus particles spread via droplet transmission, which is especially significant in the context of the recent coronavirus disease 2019 (COVID-19) pandemic. The bacteriophage φ6 of Pseudomonas syringae was used as a model of the COVID-19 virus because of its similar structure and safety in experiments. The apparatus consisted of a spiked, perforated stainless plate (S-PSP) linked to a direct-current voltage generator to supply negative charge to the spike tips and a vessel with water (G-water) linked to a ground line. The S-PSP and G-water surface were paralleled at a definite interval. Negative charge supplied to the spike tips positively polarised the G-water by electrostatic induction to form an electric field between them in which ionic wind and negative ions were generated. Bacteriophage-containing water was atomised with a nebuliser and introduced into the electric field. The mist particles were ionised by the negative ions and attracted to the opposite pole (G-water). This apparatus demonstrated a prominent ability to capture phage-containing mist particles of the same sizes as respiratory droplets and aerosols regardless of the phage concentration of the mist particles. The trapped phages were successfully sterilised using ozone bubbling. Thus, the present study provides an effective system for eliminating droplet transmission of viral pathogens from public spaces.

The purpose of the study was to construct an electrostatic insect-capturing apparatus that could be applied to a drone (quadcopter). For this purpose, a double-charged dipolar electric field screen (DD-screen) was constructed using oppositely charged insulator tubes that was then attached to a drone. For charging, the inner surface of the tubes was coated with a conductive paste and then linked to a negative or positive voltage generator. The opposite charges of the tubes formed an electric field between them and created an attractive force to capture insects that entered the field. The DD-screen constructed here was sufficiently light to enable its attachment to a drone. The screen was hung from the drone perpendicular to the direction of drone movement, so as to receive the longitudinal airflow produced by the movement of the drone. It was positioned 1.8 m below the drone body to avoid the influence of the downward slipstream generated by the rotating propellers. Eventually, the drone was able to conduct a stable flight, with sufficient endurance, and captured airborne insects carried by an airflow of 8 m/s during the flight. This study, therefore, provides an experimental basis for establishing a new method for conducting trap-based monitoring of airborne insects during remote-controlled flight through operation of a DD-screen attached to a drone.

A total of 26 Ampelomyces strains were isolated from mycelia of six different powdery mildew species that naturally infected their host plants in Japan. These were characterized based on morphological characteristics and sequences of ribosomal DNA internal transcribed spacer (rDNA-ITS) regions and actin gene (ACT) fragments. Collected strains represented six different genotypes and were accommodated in three different clades of the genus Ampelomyces. Morphology of the strains agreed with that of other Ampelomyces strains, but none of the examined characters were associated with any groups identified in the genetic analysis. Five powdery mildew species were inoculated with eight selected Ampelomyces strains to study their mycoparasitic activity. In the inoculation experiments, all Ampelomyces strains successfully infected all tested powdery mildew species, and showed no significant differences in their mycoparasitic activity as determined by the number of Ampelomyces pycnidia developed in powdery mildew colonies. The mycoparasitic interaction between the eight selected Ampelomyces strains and the tomato powdery mildew fungus (Pseudoidium neolycopersici strain KTP-03) was studied experimentally in the laboratory using digital microscopic technologies. It was documented that the spores of the mycoparasites germinated on tomato leaves and their hyphae penetrated the hyphae of Ps. neolycopersici. Ampelomyces hyphae continued their growth internally, which initiated the atrophy of the powdery mildew conidiophores 5 days post inoculation (dpi); caused atrophy 6 dpi; and complete collapse of the parasitized conidiphores 7 dpi. Ampelomyces strains produced new intracellular pycnidia in Ps. neolycopersici conidiophores ca. 8-10 dpi, when Ps. neolycopersici hyphae were successfully destroyed by the mycoparasitic strain. Mature pycnidia released spores ca. 10-14 dpi, which became the sources of subsequent infections of the intact powdery mildew hyphae. Mature pycnidia contained each ca. 200 to 1,500 spores depending on the mycohost species and Ampelomyces strain. This is the first detailed analysis of Ampelomyces strains isolated in Japan, and the first timing and quantification of mycoparasitism of Ps. neolycopersici on tomato by phylogenetically diverse Ampelomyces strains using digital microscopic technologies. The developed model system is useful for future biocontrol and ecological studies on Ampelomyces mycoparasites.

An electrostatic apparatus was constructed to capture tobacco sidestream smoke. This apparatus consisted of a perforated polypropylene plate with metal spikes and a grounded metal net arrayed in parallel at a defined interval. Spikes were negatively charged to positively polarize the net and an electric field was formed between the opposite charges of the spike tips and the grounded net. Discharge from the spike tips occurred, which depended on the pole distance and the voltage applied to the spikes. At lower voltages (<12.1 kV) that do not cause arc discharge from the tips, a corona discharge occurred with the generation of an ionic wind from the spiked plate to the net. This discharge increased in direct proportion to the applied voltage and relative humidity, while a larger corona discharge generated a stronger ionic wind. The ionic wind involved negative ions and the number of negative ions in the wind increased with increasing applied voltage. The optimal voltage (10 kV) generated sufficient negative ions to ionize smoke particles in the electric field, before the ionized smoke particles were successfully captured by the oppositely charged metal net. Thus, this study provides an experimental basis for the practical application of an electrostatic-based method to prevent the production of tobacco sidestream smoke that leads to passive smoking by non-smokers.

Genus Salacia (Hippocrateaceae) contains woody climbing plants widely distributed in India, Sri Lanka, China, and Southeast Asian countries. The stems and roots of some species of the plant have traditionally been used as a specific remedy for early-stage diabetes in Ayurvedic medicine. Recently, a variety of health foods and beverages made from the extracts of Salacia genus plants claiming the prevention and/or control of diabetes has been developed in Japan and North America. In order to distinguish and identify the species of the genus Salacia plants genetically, DNA sequences in the internal transcribed spacer (ITS) region of the nuclear ribosomal RNA gene (nrDNA) with respect to three species of the plant, i.e., S. reticulata, S. oblonga, and S. chinensis, collected in Sri Lanka, India and Thailand were analyzed and compared with each other. Among them a characteristic feature discriminable from the other two species was observed with respect to the DNA sequence of the samples identified as S. chinensis. On the other hand, no distinct difference or character which led to the identification of S. reticulata or S. oblonga was observed in the present study.

筆者らは近畿大学農学部(奈良県)においてトマトの一段採り密植栽培を実施しているが，近年，近畿地区においてもトマト黄化葉巻病の発生が問題となってきた。そこで，2007年の栽培から黄化葉巻症状の調査を開始したところ，2009年7月，養液栽培トマトに黄化葉巻の症状が確認され，温室内にタバココナジラミが発生していたことから，トマト黄化葉巻病の可能性が示唆された。本実験では，黄化葉巻の症状を示すトマトからトマト黄化葉巻病ウイルス(TYLCV)の検出を試みるとともに，タバココナジラミのバイオタイプの確認を行ったので報告する。

[要旨] トマトは、栽培種トマトと野生種トマトに大きく分類されている。栽培種トマトは我が国の主要作物であり、その用途は生鮮や加工品など多岐にわたる。また、食品機能性に富み、これまでに、抗酸化作用、抗炎症作用、抗ガン作用、抗アレルギー作用など、様々な機能性が認められている。一方、野生種トマトに関しては、既に著者らのグループにおいて、昆虫に対する忌避作用や抗菌作用などの効果を明らかにしており、さらに多くの機能性物質の存在が示唆されている。そこで本研究では、各種野生種トマトの栽培試験により優良形質のトマトを選抜し、それらの機能性成分の探索、ならびにアンチエイジング素材の開発を目的とした、生物寿命に及ぼす影響についての検討を行った。[Abstract] In order to examine nutraceutical effects of wild tomato species, we screened wild tomato species that were suitable for cultivation and extracted substances useful for longevity prolongment. Namely, twentyone of totally of 41wild tomato species used possibly produced fruits of different shapes, colors（red, green and purple）and sizes. Antioxidative and polyphenolic substances were detected in some fractions of fruit- and leaf-extracts obtained from both common and wild tomato species. All fractions of leafextracts were less effective to prolong life span of the test insect, with no relation to common and wild tomato plants. In point A, there was no significant difference in the longevity prolongment of the test insect among all fractions of both common and wild tomato plants. In point B, two fractions （hexanesoluble and ethyl acetate-soluble fractions）of fruit-extracts from both common and wild tomato plants were positive to the lifespan prolongment of vinegar fly adults. Hexane-soluble fraction of fruit-extracts from wild tomato plants was most effective to prolong lifespan of the test insect. In point C, ethyl acetatesoluble fraction of fruit-extracts from both plants showed the significant effect on the prolongment of lifespan. Antioxidants and polyphenolic substances in ethyl acetate-soluble fractions were effective to prolong lifespan of the test insect. Polyphenols are potential substances to extend lifespan of diverse species including vinegar fly. Hexane-soluble fraction of fruit-extracts from wild tomato plants was positive to the lifespan prolongment, it contained substances effective to prolong lifespan of the test insect. Judging from these results, both common and wild tomatoes are useful sources to search various nutraceutical substances for the longevity prolongment, as assessed by the insect assay system.

A new electrostatic insect-proof screen (electric dipolar screen) was developed using insulated conductor wire. Copper conductor wire is encased in a flexible transparent vinyl insulator sleeve and charged with an electrostatic voltage generator. Paired insulated conductor wires were placed in parallel with 5mm of separation and oppositely charged with 15kV DC using separate electrostatic voltage generators. A negatively charged conductor wire polarizes the insulator negatively at the outer surface and positively on the conductor side, and a positively charged conductor wire polarizes vice versa. A pair of insulated conductor wires with opposite surface charges was used as an electric dipole. An electric dipole creates an electrostatic force from positive to negative poles. This force was harnessed to trap whiteflies entering greenhouses. Dipolar wires were attached in parallel to a frame to construct an electric dipolar screen that could be fitted to greenhouse windows. The screen prevented adult whiteflies from passing through spaces (up to 30mm) between the wires of the screen, and tomato plants inside remained free of whiteflies throughout the entire 3-week experiment, in contrast to heavy infestation of all plants in the uncharged area. Thus, the electric dipolar screen is a promising tool to physically exclude flying whiteflies from greenhouses.

本実験では、顕微鏡下で標的とした単一細胞からマイクロピペットを用いて細胞内容物を吸引し、そこに存在するmRNAを鋳型とした単一細胞RT-PCR法を適用することとした。病原菌の感染によって発現が誘導される遺伝子（CHI2、GLUなど）を検索した。誘導型遺伝子の発現を厳密に評価するため、RT-PCRを行う際に、先の構成的発現遺伝子を増幅するプライマーを混合し、指標遺伝子として同時に増幅することにより、誘導型遺伝子の発現検出を行った。その結果、病原菌の感染を受けていない細胞およびその感染を受けている両者の細胞において指標とした構成的発現遺伝子は検出された。誘導型遺伝子として使用したCHI2遺伝子およびGLU遺伝子は病原菌の感染を受けていない細胞においてその発現が検出され、うどんこ病菌の感染過程において抑制される傾向にあった。

ディデネレートプライマーを利用したRT.PCR法により、甘草根のtotal RNAから糖転移酵素遺伝子を増幅した。この遺伝子はエンドウのグルクルタン酸転移酵素遺伝子と高い相同性が示され、甘草のグリチルチリン生合成に関与する糖転移酵素遺伝子であると示唆された。

近畿大学構内で発生した新しいトマトうどんこ病菌について、その特性を調査し、Oidium neolycopersiciであると同定した。また、本病原菌の他の植物に対する感染性を調べ、その宿主範囲についても明らかにした。

土壌から分離した植物根高度定着性細菌Enterobacter cloacaeにキトサン分解酵素遺伝子を導入し、本細菌に特異的に感染するファージを併用することによりキトサナーゼを利用したモニタリングシステムを確立した。

カンゾウ培養苗を用いた人工栽培によるグリチルリチン生産と、RAPD分析法によるカンゾウ種の簡易識別法について解説した。

アグロバクテリウム法を用いて薬用植物である甘草へ遺伝子導入を試みた。 効率的に形質転換体植物が作出できたことより、 2 次代謝産物の生合成を遺伝子発現レベルで制御する代謝工学に応用できうると考えられた。

トマト葉原基へ変異誘起剤処理を施し、 生長した葉において発現する変異を確認した後、 その変異葉からのカルス誘導ならびに個体再生を行なった。 その結果、 得られた再分化個体に同様の変異が認められたことから、 本法は変異育種に有効な手法であると考えた。

土壌から分離したキトサン分解性細菌の粗酵素画分をフザリウム菌に処理したところ、 抑制効果が認められた。 そこで、 本菌の生産するキトサナーゼを精製し、 アミノ酸配列を決定すると同時に遺伝子のクローニングを行なった。

RAPD 分析により 5 種のカンゾウ属植物の分類を行うことができた。 さらに、 G. glabra と G. uralensis において特異的な PCR 増幅断片が得られ、 その塩基配列をもとに作製 RAPD マーカーは、 両者を効率的に識別することができた。

RAPD 分析により 5 種の異なる甘草を分類することが可能になった｡ さらに､ 本分析法により得られた種特異的断片の塩基配列より､ これまで識別が困難であった G. glabra 種と G. uralensis 種を区別できる RAPD マーカーを作製することができた｡

Abstract Virulent bacteriophage PK‐101 was isolated from soil infested with strain K‐101 of Pseudomonas solanacearum and nucleic acid was prepared from the phages. Some chemical properties of phage nucleic acid and its infectivities to various strains of P. solanacearum were examined in the present study. By digestion with restriction endonucleases, phage nucleic acid was shown to be linear duplex DNA approximately 35 kb long. Restriction fragment length polymorphism was observed when electrophoresis patterns of enzyme‐digested PK‐101 DNA were compared with those of DNA prepared from different phage isolates. Transfection of host strains by PK‐101 DNA was carried out, and it was infectious not only to host strain K‐101, but also to other strains which were resistant to phage particles. Transfection efficiency was considerably enhanced by directly introducing phage DNA into bacterial cells by means of an electroporation. The electroporation technique was also effective to transform P. solanacearum with large‐size plasmid DNA.

本実験では、トマトから葉圏に生息するキチナーゼ生産性細菌を分離し、ニジュウヤホシテントウの生物防除を試みた。まず、最も高いキチン分解活性を示す細菌KPM.012A を中腸ペリトロフィック膜に処理したところ、キチナーゼによる分解が確認された。

本実験では、トマト葉圏から幼虫に対して食害抑制効果を示す細菌の分離を試み、生物防除資材への適用を検討した。トマト葉圏から分離された細菌を幼虫の経口から直接導入し、一定期間トマト葉を摂食させることにより食害抑制効果を示す細菌の選抜を行った。

本実験では、KPM.18P の特性を調査し、さらに定着能力を強化することとした。一般に高度葉面定着を示す細菌は生物界面活性剤を生産することが報告されていることから、本細菌の生物界面活性剤生産能について検討した。

ガン細胞特異タンパク質であるCD98の遺伝子をミヤコグサに導入し、その遺伝子の発現とタンパク質の翻訳について報告した。これらの植物はガン予防を目的とした経口ワクチンとしての利用が示唆された。

オオムギうどんこ病菌の感染を受けた子葉鞘細胞およびその隣接細胞に単一細胞RT.PCR法を適用し、感染特異的に発現する遺伝子の解析を進めている。本研究では、単一細胞から細胞内容物を吸引し、そこに存在するmRNAを鋳型としたRT.PCRを試みた。

5.フルオロインドール（5.FI）耐性植物の作出を目的として、シロイヌナズナ（品種コロンビア）からアントラニル酸合成酵素遺伝子をクローニングした後、フィードバック阻害を受けない変異遺伝子の作製を試みた。

トマトのレトロトランスポゾンの発現をRT?PCR法により検出した。Ty1/copia型およびTy3/gypsy型レトロトランスポゾンの逆転写酵素領域は、葉ならびにカルス細胞で発現していた。

ガン特異的タンパク質であるCD98の全長遺伝子を植物へ導入した。組み込まれたCD98遺伝子の発現をRT?PCR法で検出するとともに、発現タンパク質の生産をウエスタンブロット分析で調べた。

カンゾウの培養苗を用いた人工栽培によるグリチルリチン生産を目的とし、水耕栽培に用いるロックウールや種々の支持体が、カンゾウの生育特性、根の肥大化ならびにグリチルリチン生産に及ぼす影響を検討した。

本菌は絶対寄生菌であることから、特定の分子ステージにあるうどんこ病菌を大量に得ることは非常に困難であり、それぞれの器官で発現する遺伝子の解析が必ずしも容易ではない。本実験ではPricking RT?PCR法を用い、単一器官を標的として発現遺伝子の解析を行った。

トマトのレトロトランスポゾンをゲノムからクローニングし、その遺伝子解析を試みた。ゲノム上には多数のレトロトランスポゾンが存在しており、また、培養栽培において発現している新規のTy1/copia型レトロトランスポゾンをクローニングした。

Ty1/copia型およびTy3/gypsy型レトロトランスポゾンの逆転写酵素領域で保存されているアミノ酸配列からプライマーを合成し、RT?PCR分析に用いた。トマト葉およびカルスにおいて、これらは発現しており、既知Ty1/copia型とは異なる断片がカルスより増幅した。

経口ガンワクチンの開発を目的とし、ガン細胞特異的タンパク質CD98遺伝子を植物へ導入した。その遺伝子発現をRT?PCRで検出し、さらにタンパク質の翻訳をウエスタンブロット分析で調べた。その結果、組換え植物はCD98タンパク質を生産しており経口ワクチンの可能性が示唆された。

オオムギ子葉鞘の単一細胞から RT PCR により遺伝子をクローニングするため、 基礎的条件として常時発現している遺伝子のプライマーを構築し、 PCR 時の反応温度および増幅量について検討した。

カンゾウ培養細胞で発現している配糖化酵素遺伝子のスクリーニングを行った。 すなわち、 肥大根で発現している RGUTI 遺伝子をプローブとして cDNA ライブラリーをスクリーニングしたところ、 3 種の新規なクローンを分離し、 その機能と解析を報告した。

RAPD 分析により 5 種の甘草属植物を分類することができた。 G. glabra 種と G. uralensis 種のグループと G. echirata 種、 G. pallidiflora 種および G. squamulosa 種のグループに分類され、 両者はそれぞれ近縁種であることが判明した。

カンゾウの薬用成分であるグリチルリチンの生合成を明らかにするため、 それらに関与するグルクロン酸転移酵素を生根より抽出、 精製した。 約 50 KPa の分子量のタンパク質であり、 作用 PH が異なる 2 種のタンパクがグリチルリチン生合成に関与していた。

甘草のグリチルリチンに関する生合成メカニズムや遺伝子機能等の基礎的研究からグリチルリチンの生産に至るまでの応用的研究について述べた。

甘草の主成分であるグリチルリチンは､ グリチルレチン酸の 3 位にグルクロン酸 2 分子が結合したトリテルペンサボニンである｡ 今回､ グリチルリチン生合成に関与するグルクロン酸転移酵素を生根より精製し､ その諸性質について詳細な検討を試みた｡

サフランの柱頭組織（めしべ）は生薬・香料・染料・食品として多用されている。めしべを収穫するためには多大な労力が必要であり、植物個体から少量しか得ることができないため、本研究では、花茎組織から柱頭様組織を効率的に分化できる培養条件を明らかにした。また、柱頭様組織の分化に適した花茎組織部の光透過選抜法についても明らかにした。