Experiments were done to clarify whether an incidence of blossom-end rod (BER) in fruits of tomato was induced by faulty nutritional conditions in plant associated with elevated nutrients or high temperatures. Their results were as follow. The incidence of BER increased with raising temperature from 20 to 30°C, especially in air temperature as compared with rootzone temperatures. An increase in electrical conductivity (EC) of nutrient solution from 1.2 to 1.8 mS cm^-1 also increased the incidence of BER. The BER incidence due to higher temperatures was correlated with a rapid growth rate of fruits during early stages of fruit development in high temperature. There was no difference in fruit size at different EC values of nutrient solutions. Ca Content in fruits tended to decrease in the treatment inducing high BER incidence. The distribution of Ca giving 0.67-fold at the fruit apex and 0.9-fold in content at the fruit base in BER fruit at compared with that in healthy fruits. Contents of K and N in distal and basal part in BER fruits were high as compared with those in healthy fruits. The ratios of P/Ca, K/Ca and N/Ca in fruits with severe BER were high. Conclusively, the incidence of BER in fruits of tomato was induced by faulty nutritional conditions in plants associated with the rapid growth rate of fruits, high temperatures, and water deficits due to high EC values of nutrient solutions.

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Experiments were designed to clarify a role of calyx for occurring the blossom-end rot (BER) in tomatoes by regulating transpiration and Ca transport. Fruit cluster in an early stage of fruit development was treated with or without calyx lobes in combination with airflow or bagging with aluminum foil. The incidence of BER was increased by the bagging of fruits or the removing of calyx lobes, especially in summer as compared with winter culture. The incidence of BER was considerably reduced by the air flowing to fruits. In the absence of calyx lobes or in the fruit truss enclosed by bag in the early stage of fruit development, fruits were dropped or their development was greatly arrested, especially in summer, whereas their development was considerably promoted in winter. The effect of these treatments in the early stage (from 0 to 20 days after blooming) of fruit development was greater than that in the later stage (from 40 to 60 days after blooming) of fruit development. The percentages of dry matter of tomato fruit or calyx were reduced by the bagging of fruits. The Ca contents in fruit were decreased, and K and N contents in fruit were increased with the increase of BER incidence, especially at the distal end of fruit as compared with the basal part of fruit. The ratios of K/Ca, N/Ca, P/Ca and Mg/Ca in fruit were high in fruit with severe BER. Conclusively, the incidence of BER in fruit was promoted by the inhibition of transpiration of fruits without calyx or with bagging, whereas that was considerably reduced by air flow to fruit or calyx of tomato in the early stage of fruit development.

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The hulblets regenerated from mother-scale of Lilium japonicum Thunb. have grown into bulbs on the compost of vermiculite and leaf mold (1: 1 v/v) . The bulbs of 1, 2, 3, and 4 years old were grown on the same compost which added with 7g of 8N-8P-8K fertilizer per m2 as basal in March 17 and 3g of the fertilizer as side in June 10, 1992. And then the growth of the bulbs, leaf emergence and flowering were checked in harvested time. There is a positive correlation between planted and harvested times in length of circumference of a bulb. The bulb of 1 year old emerged only scale-leaf (SL) . Though the bulbs of 2 and 3 years old showed both of SL and stemleaf (STL) types, all ones of 4 years old shifted to STL type. Large bulbs showed higher rate in emergence of STL than small ones. The bulb growth of STL type was better than SL type. The flowering rates of the bulbs of 3 and 4 years old were 37.5 and 87.5%, respectively. Molformation of flowers, leaves and stems could not find in this experiment, and the regenerated plants are very similar in petal color and smell to the wild ones. The formation of new bulblets as cormels or split bulbs was found in the stem-base and the scale of the bulbs of 4 years old in the compost.

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Dyestuffs, which have the particular characteristics of being able to intercept the red (R) or far-red (FR) region, were added to clear PMMA (poly-methyl methacrylate) covering materials. Adjusting the R/FR photon flux ratio of natural radiation, these covering materials, to control the elongation of plant growth, were trial-produced. Increasing the concentration of dyestuffs, the R or FR areas are gradually largely intercepted. When a photosynthetic photon flux transmittance of 75% was decided on, R/FR ratios adjusted by these dyestuffs were calculated at 0.55 and 2.1 while that of CIE standard illuminant D₆₅ is 1.08. Two kinds of colored plastic panes of PMMA materials were produced by mixing dyestuffs into clear PMMA of 93% transmittance. The PPF transmittance of produced PMMA named R-interceptor and FR-interceptor was 69% and 70%, respectively. The R/FR ratio of R-interceptor and FR-interceptor was 0.55 and 1.57, respectively. These materials, which are able to control plant photomorphogenesis by adjusting R/FR ratio under natural radiation could be used effectively as special covering materials for horticultural plant production.

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Three growth cabinets were constructed using the following PMMA (poly-methyl methacrylate) as covering materials: 1) Red light (R) interceptor (R-intercepting dyestuff added) . 2) Normal (no dyestuff added) . 3) Far-red light (FR) interceptor (FR-intercepting dyestuff added) . R/FR (600-700/700-800 nm) photon flux ratios in R-intercepted, normal (control) and FR-intercepted cabinets were 0.53, 1.16 and 1.50 respectively. The seedlings of sunflower (Helianthus annuus L. cv. Russian Mammoth) and cabbage (Brassica oleracea L. cv. Suehiro Kanran) were cultivated in the cabinets under the same conditions of PPFD and other environmental factors. For both kinds of plants, elongation of the seedlings were significantly promoted in the R-intercepted cabinet, and inhibited in the FR-intercepted cabinet, compared with the seedling in the normal cabinet. Slight changes were also observed in other morphological characteristics. After ten days of treatment in their respective cabinets, the sunflower seedlings were transplanted into a natural greenhouse, and it was shown that they gradually recovered to the same growth state as under the control treatment. The experimental result suggested that these covering materials would be effective in controlling plant elongation in greenhouse cultivation for many kinds of crops.

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Changes of phenylalanine ammonia-lyase (PAL) activity in 1-year-old twigs of D. taitoensis and D. kaki were investigated with reference to the cold acclimation from autumn to winter. Low temperature exotherms (LTE) of twig pieces in D. taitoensis were found by differential thermal analysis (DTA) at -14.5--15.5°C in Aug. to Nov., and at -18°C in early Jan. While in 4 cultivars of D. kaki, LTE occurred at -16--19°C in early Sept., and found at -29.2°C for ‘Mapang, ’ at -26.4--27.5°C for other Japanese cultivars in early Jan. PAL activities in bud, cortex and xylem of D. kaki (‘Fuyu’) twigs gradually increased from Oct., and the highest activity was found in Dec. In D. taitoensis, PAL activity was relatively lower than in D. kaki, however, the peak activities were found in the bud and cortical tissues during the coldest part of the season. PAL activities in cortical and xylem tissues of both species increased under chilling treatment (4°C, 8h photoperiod) in early autumn. Particularly the higher activities were found in cortical tissues of kaki at 7th day and the chilling treatment lowered electrolite leakage of twigs by more than 20% in Sept. and 10% in Oct. Thus, an apparent difference was found in the ability of cold acclimation between 2 Diospyros species. D. kaki seems to have evolved the ability of cold acclimation by controlling the enzyme systems related with production of phenolic substances according to the environmental temperatures.

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The incidence of blossom-end rot (BER) and inorganic nutrient status in tomato, Lycopersicon esculentum L., plants were investigated in relation to air temperatures, air flow and uniconazole (growth retardant) spray. The plant height, plant and leaf dry weight and content of inorganic nutrients increased with a decreasing temperature from 28°C to 24°C, which resulted in drastic reduction in incidence of BER. The spray of 5 ppm uniconazole to leaves also decreased such a disorder of tomato, although the treatment reduced plant height, dry weight of some organs and total fruit yield. The incidence of BER increased with the raising temperature from 24°C to 28°C and air flow over the top of canopy or expanding leaves. On the contrary, the flowing of air over the cluster of tomatoes decreased the incidence of BER. The growth rate (GR) of fruit diameter reached a peack during an early stage, from 13 to 22 days after blooming, of fruit development of tomato grown hydroponically. The incidence of BER was observed during this stage. The maximum value of GR increased with the higher temperature or air flow to the top of canopy of tomato plant, whereas these values were reduced by uniconazole spray. The Ca contents (DW%) in fruit tended to be lower. K contents (DW%) in fruit increased with the increase of BER incidence, whereas their contents were reversely changed by uniconazole spray. Conclusively, the prevention against BER incidence is considered to be established by the air cooling or flowing in the zone only around fruit cluster. Hence, blossom-end rot of tomatoes is caused by faulty nutrition associated with low transpiration stream into fruit and high temperature at an early stage of fruit growth.

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In 1985-1987, the ecology of Shiro which had produced fruiting-body of Tricholoma matsutake was studied in the forest of Pinus densiflora, Sadogashima, Niigata Prefecture. There are three types of Shiro showing circular and crescent with pine root and independent circular with pine root. The latter one developed in the soil which the root of pine tree did not grow well. When the mycelia from the latter Shiro are mixed with the sawdust medium containing several nutrients and LVD (separated sulphite pulp waste from softwood) and incubated in the plastic case at 24°C, the fruiting-body of T. matsutake was formed 90 days after the mixing. The growth of mycelia (Z-1 strain) isolated from the fruiting-body formed in the plastic case was better than those produced in nature. Moreover, Z-1 strain formed some small fruiting-bodies in the sawdust nutrient medium containing LVD and Sphagnum sp. (commercial plant) . Other strains, however, did not form any fruiting-body in the same culture conditions. Therefore, the mycological and physiological characters of Z-1 strain isolated will be examined in further investigation.

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In vitro shoot propagation from shoot tip explants of zoysiagrass (Zoysia matrella Merr.) was achieved in agar and liquid media based on Murashige and Skoog (1962) media supplemented with various combinations of α-naphthaleneacetic acid (NAA) and 6-benzyl-aminopurine (BA) concentrations. Maximum shoot propagation was obtained with 0.5μM NAA and 5.0μM BA in agar media, and 0.05μM NAA and 0.5μM BA in liquid media. Stolons were formed in liquid media but not in agar media. Liquid media was superior for propagation of shoots to agar media as the formations of multiple shoots, stolons and roots were higher in rates.

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The net photosynthetic rate and growth of strawberry (Fragaria×ananassa Duch. cv. Houkouwase) plantlets in vitro under photoautotrophic conditions as affected by initial inorganic ion composition (modified Hoagland and Arnon, MHA; Hoagland and Arnon, HA; Murashige and Skoog, MS) and initial total inorganic ion concentration of the medium (20, 40, 60 and 80 mol⋅m^-3 for MHA media) were investigated. Three shoots at the rooting stage, each planted on a 0.13×10^-4 m³ liquid medium in a cup, were cultured in a 7.5×10^-4 m³ cylindrical polycabonate vessel. Concentrations of K⁺, Mg²⁺, NH₄⁺, NO₃^-, H₂PO_4- and SO₄^2- in 40 mol⋅ m^-3 MHA were 1.3, 1.5, 3.0, 1.1, 3.0 and 1.5 times, respectively, those in HA. The vessel with the number of air exchanges of 3.5h^-1 had four membrane microporus filters (pore diameter: 0.5μm) . Cultures were maintained in a room for 21 days at 25°C, 70% relative humidity, 2.0 mmol⋅mol^-1 CO₂, 16 h⋅d^-1 photoperiod and 160 μmol⋅ m^-2⋅s^-1 photosynthetic photon flux density provided by cool-white fluorescent lamps. Net photosynthetic rate per plantlet on day 21 was the greatest in 4.5 mol⋅m^-3 with initial phosphorus concentration of MHA and dry weight per plantlet on day 21 was the greatest in 3 mol⋅m^-3 with initial phosphorus concentration of MHA. Fresh weight, percent dry matter, leaf area and transpiration rate per plantlet on day 21 were greater in MHA with initial total inorganic ion concentrations of 40 and 60 mol⋅m^-3 than in HA, MS and MHA with initial total inorganic ion concentrations of 20 and 80 mol⋅ m^-3. Forty and 60 mol⋅ m^-3 with initial total inorganic ion concentration of MHA and initial phosphorus concentration of 3 and 4.5 mol⋅m^-3 gave significantly enhanced net photosynthetic rate and growth of the plantlet under photoautotrophic conditions.

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We applied the eddy accumulation theory with conditional gas sampling method for practicable gas flux measurement in natural condition. A new gas sampling system based on this theory was developed and the reliability of this method was checked. The coefficient b of the theory was calculated by using the sensible heat flux and the difference of averaged upward air temperature and downward one. The coefficient b has an almost constant value of 0.53. Sensible heat flux measured by the eddy accumulation showed a close agreement with that by the Bowen-ratio method. Also, CO₂ flux by the eddy accumulation method and the concentration gradient method showed a good agreement. These results suggest the satisfactory reliability of the eddy accumulation method with conditional gas sampling.

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