Redox regulation is a central control element across a broad spectrum of biology. Thioredoxin (Trx), a widely distributed disulfide enzyme, participates in the control of numerous target proteins, thus playing a key role in regulatory processes. Identification of Trx′s targets will therefore aid the elucidation of redox biology. Two recently developed procedures, one based on thiol-specific probes and the other on affinity trapping, have facilitated the labeling or isolation of potential Trx targets that were later identified with proteomic approaches. Accordingly, the number of identified targets in plants has increased to 400. This review describes recent advances in proteomic strategies that are effectively overcoming challenging problems such as the evaluation of target authenticity. Also presented are two industrial research areas, food processing and medical investigation, in which disulfide-related proteomic studies beyond plant biology are underway.

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A stereo vision system for agricultural tractors was developed. Two kinds of stereo camera unit were manufactured: one of which is mounted on the front of the tractor and the other on the cabin roof. The system can detect various formed or shaped objects, such as crop rows, ridges, uneven surfaces after tilling and marker traces in front of the tractor in agricultural fields. The system generates distant images with a 0.1-second cycle, while an internal algorithm installed in the system analyzes this distant image data three-dimensionally, and detects the positions of objects. The positional data was transferred to a steering controller of the tractor and tilling work was performed automatically by tracking these objects.

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The tilling robot mainly comprises: a robot vehicle called ROBOTRA, which is remodeled to control parts of commercially available tractors automatically, a navigation system called XNAV, which detects and outputs robot positioning information using an auto-tracking type surveying device, and a controller with read operation software to execute path planning and control the robot vehicle. The robot has ability almost equivalent to that of customary manned-driven tractors and can perform unmanned rotary tilling on a rectangular field. To improve its adaptability during unmanned operation, we remodeled it so that it could perform path operations differing from customary rotary tilling and performed field tests. We proposed two different path operation methods: “diagonal operation”; performing returning straight operations diagonally against the longer side of the field; and “round operation”; performing straight operations parallel to the four sides in the entire field area, and developed a software package for the same. Following field tests using the software, we confirmed that favorable unmanned operation could be achieved through both methods.

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Natto, a Japanese soybean food fermented by Bacillus subtilis (natto), are often spoiled by bacteriophages. The contamination of natto by phages causes a rapid loss of viscosity of poly-γ-glutamic acid (PGA), which is a key factor affecting the quality of natto. B. subtilis (natto) phages were classified into 2 groups (I and II), based on the homology of their genomic DNA. A phage JNDMP (Group I) has a head (diameter, 60 nm) and a flexible tail (7 × 200 nm) and requires magnesium ions for propagation. JNDMP was found to be a generalized transducing phage. A virulent phage ONPA (Group II) has a head (diameter, 89 nm) and a contractile tail (9 × 200 nm) with a sheath (width, 23 nm) and requires no additional magnesium ions for propagation. The loss of PGA due to contamination of the phages is attributed to a PGA hydrolase, PghP, coded in the phage genome. The enzyme hydrolyzes PGA to oligomers via an endopeptidase-type action and rapidly reduces the PGA viscosity. These days, although contamination of natto with phages is relatively infrequent, phages still exist on the floors of factories. Controlling them via thorough cleaning of factories and hygiene education for workers seem to be the most important solutions.

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To establish sustainability in the dairy industry, it is important that cows become pregnant at a biologically optimal time and at an economically profitable interval after calving. In this review, the results obtained from Holstein cows in an experimental herd for dairy research are summarized. First, the postpartum follicular dynamics of lactating cows were traced in relation to their fertility. The premature initiation of ovarian activity does not always improve the fertility of cows, as indicated by the number of days open. Second, the occurrence of anestrous ovulations during the early postpartum period was analyzed with reference to the frequency of reversion to anestrus. The premature onset of estrous activity also failed to improve fertility, and relapse into anestrus after the onset of the estrous cycle often occurred during the breeding period. Third, both the emergence and fate of cystic ovarian follicles and repeated follicular waves during the early postpartum period were examined, and it was revealed that neither conditions exerted a significant impact on the cow′s fertility, as indicated by days open. The importance of appropriate estrous detection was underlined and discussed as a major concern to improve the fertility of high-yield dairy cows.

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‘Sunrouge’ is an anthocyanin-rich tea cultivar, which was selected from the population derived from the natural crossing of ‘Cha Chuukanbohon Nou 6’ (C. taliensis X C. sinensis). The anthocyanin content of ‘Sunrouge’ exceeded that of ‘Cha Chuukanbohon Nou 6’, which was bred as an anthocyanin-rich tea parental line. However the anthocyanin content of ‘Cha Chuukanbohon Nou 6’ depends on the plucking period, growth stage and the part of the new shoot. The emergence of the ‘Sunrouge’ crop is moderately early, as with the Japanese leading cultivar ‘Yabukita’ (C.sinensis var. sinensis). The ‘Sunrouge’ tree is of the medium type and has many branches in comparison to typical cultivars. In terms of resistance, it is slightly resistant to anthracnose (Discula theae-sinensis (I. Miyake) Moriwaki & Toy. Sato comb. nov.), highly resistant to gray blight (Pestalotiopsis longiseta (Spegazzini) Dai & Kobayashi) and has relatively low resistance to brown blight (Glomerella cingulata (Stoneman) Spaulding & Schrenk). The survival rate of ‘Sunrouge’ is lower than ‘Yabukita’ and the other control cultivars in the cutting propagation. We try to propagate using the photoautotrophic culture method and the propagation of ‘Sunrouge’ was incident-free. We anticipate its use as a functional food and the material of the natural pigment.

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A survey of the geographical distribution of pathogenic races of Xanthomonas oryzae pv. oryzae (Xoo) causing bacterial blight (BB) of rice in northern Vietnam was conducted. We characterized strains of Xoo collected from nine regions in this part of Vietnam in 2001 and 2002 using polymerase chain reaction (PCR)-based DNA fingerprinting and virulence analysis. The pathogenicity of Vietnamese 84 strains was tested for their virulence to BB near-isogenic lines with a single resistance gene. Based on virulence analysis using 11 differential lines (IR24, IRBB1, IRBB2, IRBB3, IRBB4, IRBB5, IRBB 7, IRBB10, IRBB11, IRBB21 and Taichung Native 1), each harboring a single resistance gene, four pathotypes (tentatively designated as races G1 to G4) were identified. All strains were virulent to the resistance genes Xa1, Xa2, Xa10, Xa11, Xa14 and Xa18, and xa5 and Xa21 were effective against a major portion of the Vietnamese Xoo population; followed by Xa7. Most of the Vietnamese hybrid and improved varieties cultivated in northern Vietnam were susceptible to all races and no Vietnamese variety was resistant to all races. Our study revealed that strains from northern Vietnam comprised two major races (G2 and G3) and two minor races (G1 and G4), which were widely distributed and detected at lower frequencies, respectively, in northern Vietnam. Seventy six strains of Xoo were analyzed by DNA fingerprinting using two PCR-based assays. Two groups, designated as clusters I and II, were respectively identified, in which cluster I contained race G4 strains and cluster II race G1 strains. Combining DNA and pathotype analysis, we hereby present the situation of Xoo recently isolated in northern Vietnam.

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Solitarious phase locusts are cryptic animals and usually seek shelter in plants. This trait was thought to be a specific antipredator strategy associated with the solitarious phase. However, information on preferences for particular shelter plants and sheltering behavior remains limited. In the present study, small-scale field observations were conducted to investigate the sheltering behavior of the solitarious phase of the desert locust, Schistocerca gregaria, in relation to plant species and size. A spiny plant, Fagonia arabica, and two spineless plants, Nucularia perrini and Stipagrostis plumosa, were identified at the survey site. Although the size of F. arabica did not differ significantly from that of the two other plant species, almost all the solitarious locusts used F. arabica for shelter. Locusts were found on a majority (78%) of the individual F. arabica examined, but the number of sheltering locusts varied. The F. arabica plants with locusts were significantly larger than those without. A positive correlation was found between the total number of sheltered locusts (nymphs and adults) per individual plant and the plant size (m³). The same tendency was observed for nymphs and adults alike. The local densities (no. of sheltered locusts / plant size (m³)) remained constant over a range of plant sizes. These results might indicate that solitarious locusts selected their shelter plant based on its species and size. Because F. arabica is a spiny plant, we concluded that solitarious locusts use not only visual but also physical defense mechanisms as antipredator strategies.

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Five different cooking methods - blanching, boiling, steaming, sautéing and high temperature (121°C) cooking - were applied to Ocimum herbs. Four Ocimum species - O. americanum (hairy basil), O. tenuiflorum (holy basil; syn. O. sanctum), O. basilicum (sweet basil) and O. gratissimum (wild basil) - were used to determine the effect of heating on their antioxidant capacity, total phenolic content, and presence of phytochemicals. Cooking with excess water, blanching, and boiling resulted in a reduction in both antioxidant capacity and phenolic content. HPLC chromatograms revealed that rosmarinic acid leached from the sweet basil leaves into the cooking water, in which sinapic acid was also detected. Meanwhile sautéing, as well as steaming at atmospheric and high pressures respectively, generally enhanced the antioxidant capacity of Ocimum, which was related to an increase in phenolic content. Similar chromatograms were detected in fresh, atmospheric steamed, and sautéed leaves, although the intensity varied. A major compound of the studied Ocimum herbs, rosmarinic acid, although found to increase in sautéed leaves, was substantially minimized in leaves steamed under pressure.

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To validate the utilization of organic matter, mainly composed of cellulose derived from mangrove trees by bivalves, we analyzed the cellulase activity in blood cockles (Anadara granosa) in the Mantang Mangrove Forest Reserve, Malaysia. In an agar plate assay, unstained circles due to cellulase activity were clearly detected in the extract of blood cockle digestive organs. Additionally, SDS-PAGE zymographic analysis revealed intensive active bands at 9.5 kDa and weak smear bands above 24.5 kDa. These results clearly showed that the blood cockle, the dominant mangrove bivalve species, possesses cellulase activity used to break down cellulose derived from mangrove trees. The present paper first reports the occurrence of the cellulose breakdown function in a mangrove bivalve, blood cockle, via biochemical analyses and suggests the possible ecological function of this species in the mangrove food chain.

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