Indole-3-acetic acid (IAA) endogenous levels were determined by liquid chromatography-mass spectrometry, diffusible levels were determined by fluorometric detection and polar transport activity was determined by radioactive IAA in tomato plants. IAA concentration in the apoplast (AP) solution was higher than those in the symplast (SP) solution in both upper and lower parts of stems. It is suggested that the amount of polar IAA transport might be only 19% of the amount of endogenous IAA in stems. In fruits, concentrations of abscisic acid (ABA) were high in the pericarp, axis and the locule tissue in the early growth stages. In seedless fruits of parthenocarpic tomato, the levels of IAA, gibberellic acid₁ (GA₁), trans-zeatin (Z) and trans-zeatin riboside (ZR) were analyzed. IAA concentrations of the pericarps and partitions were higher in fruits of 8 cm in diameter (8-cm-fruit) than in 6-cm-fruit. In the partitions, IAA concentrations of SP were higher than those of AP solution. The SP of the partitions in 6-cm-fruit had the highest concentration of Z and was 2.7 times greater than the AP. The ZR concentration in locule tissues in 6-cm-fruit was the highest. These results suggest that the sites of synthesis may be the SP of partitions for IAA and Z, and locules for ZR.

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Legislation represented by the Livestock Waste Disposal Law and Compost Quality Control Law were enacted in order to reduce the excessive use of chemical fertilizer and disposal of untreated livestock waste. These laws encourage the replacement of chemical fertilizer use with livestock waste compost. The potential supply of nitrogen (N), phosphorus (P₂O₅) and potassium (K₂O) from compost was estimated using computer software and prefectural and municipal data from the 2000 Census of Agriculture in Japan. Use of N, P₂O₅ and K₂O as chemical fertilizer in Japan was also estimated by the questionnaire data by the Ministry of Agriculture Forestry and Fisheries and the 2000 Census of Agriculture. The percent of chemical fertilizer replaceable with livestock waste compost was calculated by dividing the supply from compost by the use of chemical fertilizer on the basis of N, P₂O₅ and K₂O. Average and range of replaceable percent was 20.4% (106.9-7.1%), 21.8% (105.3-7.0%) and 31.5% (124.1-7.6%) in N, P₂O₅ and K₂O, respectively, among the 47 prefectures. The range in about 3,300 municipalities fluctuated between 2,047-0%, 3,762-0%, and 3,207-0% in N, P₂O₅ and K₂O, respectively. The significance of the data is discussed in the text.

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A field experiment was carried out from October 1999 to September 2001 to establish a cropping system with Italian ryegrass (Lolium multiflorum) and natural-reseeded barnyardgrass (Echinochloa crus-galli) in an abandoned paddy field. Ryegrass was sown in October 1999 and 2000, and barnyardgrass was sown only in October 1999. A split-split plot arrangement was applied with the ryegrass varieties (an early-maturing type (EM) and a mid- to late-maturing type (LM)) as the main plot factors. The subplot factor was barnyardgrass at various sowing rates (100, 200, and 300 g/a). EM and LM were harvested twice and once, respectively, the following spring, and barnyardgrass was harvested twice: once in the summer and once in the autumn in both the EM and LM plots. In both years, the ryegrass yields depended significantly on the variety: the yield of EM was greater than that of LM. The first crop yields of barnyardgrass were affected by the preceding ryegrass varieties: greater yields of barnyardgrass were obtained when EM was the preceding crop than when LM was. The barnyardgrass sowing rate had no significant effect on either the first or the second crop yields. A sufficient number of seeds were produced to naturally establish a sward of barnyardgrass the following year in both the EM and LM plots. To verify the feasibility of this cropping system with ryegrass and barnyardgrass,we applied the system to a small field owned by a cattle farmer. The productivity cost of using this cropping system for grass production, excluding the cost depreciation for farm equipment, was comparable to the price of imported hay.

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Plasma membrane H⁺-ATPases play important roles in plant growth by keeping a proton gradient across the membrane. Although cold or pathogen stress affects the activity of the H⁺-ATPase and plant growth, its regulatory mechanisms are not fully elucidated. A rice 55-kDa calcium-dependent protein kinase was activated on cold treatment and pathogen infection. Here we showed that the kinase phosphorylated two Thr residues in the auto-regulatory domain of the H⁺-ATPase in vitro. Phosphorylation of these Thr residues might contribute to the ATPase activity regulation during cold or pathogen stress.

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The present study was conducted to clarify the effect of temperature and daylength on heading in diploid rhodesgrass cultivars. Three diploid cultivars, Tochiraku-kei, Fords-Katambora and Pioneer, were planted 9 times at 10-day intervals between April 24 (I) and July 14 (IX) in 1975. In 1976 the 3 cultivars were planted 3 times at 1-month intervals on May 4 (II), June 4 (V) and July 4 (VIII) under 5 daylength treatments of natural daylength (ND), 12 h daylength (12 h), 24 h daylength (24 h), 24 h/ND,and 24 h/12 h. DH (days to heading) decreased linearly with the increase in DMT (daily mean temperature) commonly in the 3 cultivars in 1975, suggesting that temperature is a major factor determining DH in diploid rhodesgrass. This relationship is described by a linear regression equation between DH and DMT in the period from sowing to heading date. From the results in 1976, a short daylength is considered to have an effect for accelerating flower initiation of diploid rhodesgrass under temperatures more than 22ºC. These research findings would be useful in diploid rhodesgrass for estimating the first cutting time and/or seed harvesting time, and for conducting effective reproduction in greenhouses during winter.

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Bacillus subtilis RB14-C, which is a streptomycin resistant mutant of B. subtilis RB14 isolated from compost, produces an antifungal peptide, iturin A, and was evaluated for its suppressive ability against damping-off of tomato seedlings and Phomopsis root rot of cucumber. In damping-off disease of tomato seedlings caused by Rhizoctonia solani, RB14-C cell suspension treatment did not suppress the disease occurrence whereas germinated seed treatment of the RB14-C cells reduced the occurrence of the damping-off. In both treatments, iturin A could not be detected from the treated soil. In the Phomopsis root rot of cucumber, root immersion treatment of cucumber seedlings with RB14-C cell suspension at the time of transplanting effectively suppressed the root rot, resulting in growth recovery 50 days after the treatment even though the initial growth was retarded due to the Phomopsis infection. These results suggest that germinated seed treatment of RB14-C cells and root immersion treatment with RB14-C cell suspension can be applied as promising biological control practices of the damping-off of tomato seedlings and the cucumber Phomopsis root rot, respectively.

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Saponin(s) was extracted from tea seeds, and its effect on the vase life, transpiration from leaves and hydraulic conductance of stem segments in cut roses (Rosa hybrida L. cv. Sonia) were investigated. The continuous treatment with tea-seed saponins (TSS) at 20 mg L^-1 significantly extended the vase life of cut rose flowers, but those at other concentrations did not. The volume of water uptake and water loss by the cut flowers decreased with increasing concentration of TSS. TSS induced stomatal closure. In cut flowers kept in water, hydraulic conductance of the stem segment decreased with time,and 20 mg L^-1 TSS treatment considerably suppressed this decrease. The results show that TSS markedly inhibited transpiration from leaves and suppressed decrease in hydraulic conductance, which may be responsible for a significant increase in vase life.

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Climatic change through global warming and drought is a major issue for agricultural production. Most researchers who discuss climate changes report the yield changes estimated by using crop process models; however, studies focusing on the impact of climatic change on agricultural product markets are very few. This paper examines the relationship between climatic change and world food markets, i.e.,supply and demand of crops, by using a world food model and newly estimated yield functions. These yield functions include rainfall and temperature as climate variables, and the estimated parameters are used in the world food model. The stationarity of these yield data is tested and appropriate functional forms are selected. The results suggest that yields of major crops will decrease because of rising temperatures in many countries and regions, however, market price impacts of changes in production of these crops are not large because of trade. The countries which suffer severe damage because of higher temperature may need to consider changes in cropping patterns and practices.

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The effects of plant growth regulators on fruit set of tomato (Lycopersicon esculentum Mill.) under high temperature were examined in a controlled environment and a field under rain shelter. Tomato plants exposed to high temperature (34/20ºC) had reduced fruit set. Treatments of plant growth regulators reduced the fruit set inhibition by high temperature to some extent, especially treatment with mixtures of 4-chlorophenoxyacetic acid (4-CPA) and gibberellins (GAs). In the field experiment,tomatoes treated with a mixture of 4-CPA and GAs showed increased fruit set and the numbers of normal fruits (excluding abnormal types such as puffy fruit) were more than the plants treated with 4-CPA alone during summer.

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Water was circulated between shrimp and mangrove ponds to process effluent from shrimp aquaculture using mangrove trees at the Samut Songkhram Research Station, Kasetsart University, Thailand. Shrimp growth was faster in the ponds circulated with water from mangroves during the first 63 days of culture, before mass mortality occurred. Mass mortality of shrimp occurred after 63 days of culture. Though a load reduction effect to the environment was observed in the nitrogen and phosphorus budgets, this experiment was terminated prior to completion due to mass mortality. Further experiments on processing effluent with mangroves are needed.

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