Seed vigour is accepted internationally as a quality index of seed, while it has not been recognized in Japan. This paper describes the concept, the definition and testing methods of seed vigour, and explains differences between germination percentage and seed vigour by introducing proceedings of seed science in overseas. Thereafter, possible applications of seed vigour for various Japanese agriculture scenes are proposed.

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The effect of strong acid electrolyzed water (SACEW) on prevention of bacteria growth and burdock root browning in comparison with citric acid that is used as food additive was investigated. Both citric acid and SACEW were applied at the farm gate and kept under similar low temperature (8-10℃) preservation conditions as those applied during their post-harvest handling to the final consumer. As a result, treatment of burdock root using SACEW suppressed the red (a^*) in both its surface and section and increased white stronger browning index (L^*) as compared to citric acid during the 4-8 days of post-harvest storage. Moreover, since soaking of burdock root in SACEW for 20min resulted into a 2log bacteria reduction (log10CFU/g) as compared to 1log reduction achieved by citric acid at equal contact time, it can therefore be concluded that SACEW gives better results in terms of both bacteria and browning control on burdock root than citric acid.

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In this paper, the bacillus control method in fresh water including agricultural water was examined by applying the generation principle of the strong acid electrolyzed water with a circulation type electrolysis device by which the acid electrolyzed water which had gone out of anode side of electrolytic cell with diaphragm was introduced into the cathode side again. As a result, when sterilized water obtained by applying the voltage of 50V or more with EC100μS/cm or more, it was confirmed that no growth of L. pneummophila bacterium (initially 10CFU/mL) was observed. Similarly, when sterilized water obtained by applying the voltage 10V or more with 300μS/cm or more was used, it resulted in undetectable levels of Escherichia coil (initially 10^5CFU/mL). In addition, it was confirmed that there were small water quality (pH, EC) changes according to applied voltage. It was possible to use this device in water resources where the bacterium exists such as underground water and coolant waters, and it was suggested that it be a useful technology in industry.

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The available chlorine concentration of 100-200mg/L was achieved by dilution of a marketed sodium hypochlorite solution (pH11-12) using tap water. At this concentration, HClO was about 2-3mg/L. In an in vitro study using Escherichia coli, it was confirmed that the sterilization effect of sodium hypochlorite water depends on the density of hypochlorite in acidic region. After soaking lettuce in sodium hypochlorite (ACC200mg/L-5min, 100mg/L-10min), the rinsing water pH was changed. The result had the same tendency in acidic and alkaline regions. However, the rinsing water of pH10 and of ACC800mg/L and pH10.43 were more effective in killing E. coli. Thus, there might be another sterilization mechanism apart from the existence of hypochlorite in alkaline region. It is known that NaOH has washing and flaking effects. For its alkalinity, the bactericidal effect was accelerated by flaking E. coli from lettuce surface. When sodium hypochlorite solution was adjusted with pure water, the available chlorine concentration of 100-200mg/L was the best for sterilization. It was confirmed that to improve the effect of killing E. coli on lettuce, the rinse water pH should be adjusted to 4 or less.

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Volatile compounds in shoots and leaves of bahiagrass (Paspalum notatum Flugge.), Vulpia myuros (L.) C.C. Gmel., and Vulpia megalura (Nutt.) Rydb. were identified by head-space methods using a gas chromatograph-mass spectrometry (GC-MS). Volatile compounds such as nonanol, 2-ethyl-1-hexanol, 2-methyl-1-propanol, nonanoic acid-ethyl ester, and octanoic acid-ethyl ester were identified, and their concentrations in these grasses were analyzed. When the effects of some of the identified volatile compounds on the growth of several kinds of soil-borne plant pathogens and beneficial microorganisms were investigated, all were found to inhibit the growth of soil-borne pathogens such as Fusarium oxysporum f. sp. lactucae, Rhizoctonia solani, and Rosellinia necatrix. In particular, 2-ethyl-1-hexanol remarkably inhibited the growth of these pathogens. Each volatile compound, however, had little or no inhibitory effect on the growth of beneficial bacteria such as Bacillus subtilis, Burkholderia cepacia, Paenibacillus polymyxa, and Pseudomonas stutzeri. Some volatile compounds also slightly stimulated the growth of these beneficial bacteria. Furthermore, the hyphal growth of Glomus caledonium, an arbuscular mycorrhizal fungus (AMF), was not inhibited at concentrations sufficient to suppress the growth of soil-borne pathogens. These results suggest that AMF and beneficial bacteria propagated in/on bahiagrass, V. myuros, and V. megalura, as a great advantage of the sod cultural system using these grasses at orchards, show little or no damage, but that the growth of soil-borne diseases would be severely inhibited by volatile compounds evolved from the grasses.

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Effects of overhead application of liquid fertilizer on the growth and nutrition of one-year-old 'Miyagawa Wase' satsuma mandarin (Citrus unshiu Marc.) trees grafted on trifoliate orange were investigated in pot (50L) experiments. The experimental set was consisted of liquid fertilizer, high-analysis compound fertilizer, organic-mixed fertilizer, organic fertilizer and non-fertilizer plots. The liquid fertilizer was prepared by dissolving solid mixed fertilizer at 300- and 150-fold dilution. The nitrogen concentration of 300- and 150-fold dilution was 500 and 1000ppm, respectively. The liquid fertilizer was applied 18 times for 300- and 150-fold dilution and 6 times for 150-fold dilution. In all plots the same total amount of nitrogen equivalent to 4.33g per pot was applied except non-fertilizer plots. The inorganic nitrogen content of soil was higher in the liquid fertilizer plots than the other plots, but there was no difference among the liquid fertilizer plots. The tree dry weight of liquid fertilizer plots was similar to that of the high-analysis compound fertilizer plots, the organic-mixed fertilizer plots and organic fertilizer plots. The content of three major elements in the trees was similar in all fertilizer treatments. The liquid fertilizer was similar to organic-mixed fertilizer and organic fertilizer in absurption efficacy of three major elements. And there was no difference among the liquid fertilizer plots. The high-analysis compound fertilizer showed higher nitrogen efficacy than the liquid fertilizer. The 150-fold dilution 18 times plots showed similar or slightly greater content of three major elements compared with 150-fold dilution 6 times plots.

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The objective of this study was to investigate micromorphological differences between ray florets and disc florets of garland chrysanthemum by observing their development with a scanning electron microscope (SEM). Capitulum initiation was started with the differentiation of floret primordium on the apical meristem. Capitulum development of garland chrysanthemum was divided into 11 stages: vegetative stage, dome stage, floret differentiation stage (early, intermediate, late), disc floret development stage, ray floret development stage, middle floret development stage, corolla elongation stage of ray florets (early, late) and anthesis. Ray and disc floret development were each divided into 8 stages. Ray florets were at the peripheral part of capitulum and disc florets were located at a more inner part of capitulum. Five stamens of ray florets were differentiated at the stamen differentiation stage and it was the same as for disc floret. Thereafter, stamen development stopped at pistil differentiation stage and was aborted later at the corolla development stage. On the other hand, five stamens of disc florets were differentiated at the stamen differentiation stage. Afterwards, the stamens continued to develop and pollens were formed in the anther at the late stamen development stage. Although there was no vascular bundle development at the basal part of stamens of ray florets, they could be observed in disc florets. Although the entire corolla of ray florets elongated up to the pistil differentiation stage, only three lobes elongated after this stage and they reached about 2cm in length at anthesis. On the other hand, the entire corolla of the disc florets continued to elongate till anthesis, reaching only about 2-3mm in length. The vascular bundle development of the corolla was different between ray and disc florets. Although ten vascular bundles of corolla in ray florets developed, only five vascular bundles of corolla in disc floret were observed.

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Effects of harvest time and defoliation treatment on yield of black soybean that showed delayed leaf senescence were investigated. Harvest were conducted at 26, 17, 7 or 0 days before the normal maturity day (DBM) of 3rd December 2007. As defoliation under standing status (DSS), all leaf blades and petioles were removed at 26DBM and then kept standing status until harvest. As defoliation during air-dried period (DAD), they were removed at just after harvest. As control (CONT), no defoliation was done. After harvest, all plant samples were air-dried in a rain shelter greenhouse. Yield and percentage of perfect seeds of DSS were inferior to those of CONT and DAD, especially early harvest day. Yields harvested at 26 and 17 DBM of CONT were slightly superior to those of DAD, although yields harvested at 7 and 0DBM were similar to each other. Yield, percentage of perfect seeds and perfect seed weight of CONT and DAD tended to increased with later harvest day until 7DBM. These results indicated that nutrients were translocated from leaf blades and petioles to seeds not only standing period but also during air-dried period until about 10DBM. To achieve the similar yield harvested at normal maturity stage and to ensure the enough air-dried period of black soybean that showed delayed leaf senescence, suitable harvest time is 10 to 20DBM and when harvest at 20DBM, leaf blades and petioles were remained during air-dried period.

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