Experiments were performed to determine the effects of coating and adhesive on the inoculation of Rhizobium meliloti to alfalfa seeds. They were compared with conventional inoculation methods, such as peat base and vacuum processing, for nodule formation and seedling growth during establishment. The results are summarized as follows : 1. Inoculation to seeds with a coating and an adhesive produced a rapid and high nodule formation from the early seedling stage. On the other hand, inoculation by peat-base and vacuum processing methods slowly formed nodules, and their nodulating efficiencies did not differ from uninoculated controls during the early seedling growth. Thus, the dry matter yield and leaf color of the first harvest were higher for inoculations with a coating and an adhesive than those for other inoculation methods. However, there were no differences between inoculation methods for nodulation and plant growth at the second harvest. 2. Inoculations with coating, regardless of the different manufactured products, resulted in excellent nodule formation from the early seedling stage. The same effect of coating was also shown for inoculation with different rhizobia strains. 3. It is concluded that the use of alfalfa seeds inoculated with rhizobia by a coating and an adhesive is highly efficient for establishment because the coating and adhesive promote rapid and early nodule formation and seedling vigour.

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Influences of hot summer environments on jaw movements during grazing and rumination were investigated. Using ambulatory data-logging apparatus, 1) the number of jaw movements per min and 2) the number of pauses (> 3 sec) between jaw movements per min in a Holstein dry cow grazed on pasture were recorded for 6 days in both late July and middle September. The number of jaw movements per min during grazing in late July decreased by 5.3% in the 9-h daytime (07 : 00 to 16 : 00 h) and 3.8% in the 15-h nighttime (16 : 00 to 07 : 00 h) as compared with that in middle September. The number of jaw movements per min during rumination in late July also decreased by 12.6% in the 9-h daytime and by 5.2% in the 15-h nighttime as compared with that in middle September. Moreover, in late July, the number of jaw movements during rumination in the 9-h daytime decreased by 9.3% as compared with that in the 15-h nighttime. Total jaw movements per day and jaw movements during grazing or rumination per day in late July decreased by 27 to 30% as compared with that in middle September. Grazing and rumination times per day in late July decreased by 23 to 24% as compared with that in middle September. It was revealed through the present results that a daily pattern of grazing and rumination was influenced by the hot summer environments showing reduced daily grazing and rumination times and significant reduction of the number of jaw movements per min during grazing and rumination.

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Alfalfa (Medicago sativa L. cv. Natsuwakaba) was harvested at vegetative, late vegetative, budding, early bloom, full bloom, and seeding stages of growth. Ethoxyquin was mixed with a half of the chopped herbage at the level of 1 g/kg before fractionation. The chopped herbage was mechanically divided into juice and pressed cake. The juice was injected with steam and the resultant coagulum was recovered by centrifugation and freezedried. The powder obtained was referred to as leaf extract. The dry matter yield of the crop material increased as the plant approached maturity but the protein, β-carotene and xanthophyll contents decreased. In leaf extracts, the protein concentration was fairly constant and not greatly affected by the physiological age of the plant. In contrast, the β-carotene and xanthophyll contents increased until the late vegetative stage but decreased rapidly as the crop reached the seeding stage. The dry matter yield of the leaf extract was highest at vegetative-late vegetative phase. After the full blooming stage, the dry matter and crude protein yields of press cake were extremely increased but those of leaf extract were decreased suggesting the reduction of mechanical cell rupture at the processing. The β-carotene and xanthophyll in press cake decreased as maturity progressed but since the carotenoid content is inherently low, the decrease was not remarkable, unlike in the leaf extract. Ethoxyquin was an effective antioxidant during herbage processing and improved the stability of β-carotene and xanthophyll both in the leaf extract and press cake.

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A field experiment was conducted to investigate the effect of drought stress on growth and leaf water relations in six maize cultivars (Zea mays L.) during the vegetative growth stage. Twenty days after sowing, four different soil moisture treatments were imposed ; 1) soil water table maintained at 19 cm deep (control, HM treatment), 2) 45cm deep (mild water stress, MM treatment), 3) 90 cm deep (moderate water stress, LM treatment) and 4) 190 cm deep (excessive water stress, SLM treatment). A wide range of differences in growth was observed among cultivars under different soil moisture levels. Mid-day leaf water potential was higher in drought tolerant cultivars P3358, FFR 915 C and K 8388 than in drought susceptible cultivars choko, P3424 and JX77. Under moderate and excessive water stress conditions (LM and SLM treatment), differences in leaf water potential among cultivars were related to the difference in capacity of osmotic adjustment. Degree of leaf rolling was smaller in drought tolerant cultivars which maintained a higher osmotic adjustment under moderate and excessive water stress treatments (LM and SLM treatments). However under the mild water stress condition (MM treatment) a difference in osmoregulation among cultivars was not observed. The degree of leaf rolling in drought tolerant cultivars was lower than drought susceptible cultivars. Differences in leaf rolling may possibly due to the cultivar differences in water absorption. Root exudation rate, an indicator of the water absorption capacity by roots, was greater in drought tolerant cultivars.

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Starch metabolism in the tap roots of alfalfa (Medicago sativa L. var. P 5444) after defoliation was studied using a one-year-old stand. Starch concentration decreased rapidly during the first 14 days after defoliation. Activities of a-amylase and debranching enzyme increased steadily during the first 18 and 16 days, respectively, suggesting the involvement of the enzymes in the breakdown of starch. Concentration of slightly-soluble glucan remained constant during the first 8 days, and that of readily-soluble one increased during the first 6 days. Hydrolysates of pullulan by debranching enzyme were eluted as one peak and the elution of the peak was delayed as the hydrolysis proceeded, indicating that the action of the enzyme was endo-type. Maltose concentration and jS-amylase activity increased concomitantly on the 6th day. Concentrations of sucrose, glucose and fructose also increased at the early stage of regrowth.

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Among the districts which form an island arc of Japan, the Tohoku district is a best object for studying a crust formation mechanism based on the plate tectonicstheory. In this district, the crust movement often formed grasslands by lowering the effective water level and favoring the herbaceous plants. Iwate Prefecture has the largest area of public grassland in Honshu. Ninety percent of the grasslands are distributed in the Kitakami mountains which are made of Mesozoic and Paleozoic layers, and in the lava plateaus of Tamagawa large-scale pyroclastric flow which accumulated at the end of the Tertiary period asa result of a precursory activity of the backbone volcano line. The majority of the grasslands are used for pasturing Japanese Shorthorn cattle.

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Akita Prefecture which faces the Japan Sea has large area of plateaus. The plateaus, however, are not suitable for grassland farming or field crop cultivation, because they are the dissected plateaus formed by the rise of green-tuff, sediments of seabed eruption. In Akita Prefecture, paddy rice is almost the only crop, and milk and vegetables are not self sufficient. Such geological and agricultural characteristics are also found in the other prefectures along the Japan Sea in northert Honshu, i.e. Aomori, Yamagata and Niigata Prefectures. The four prefectures facing the Japan Sea have smaller area of public grassland and smaller number of cattle than the prefectures facing the Pacific Ocean in northern Honshu.

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White clover (Trifolium repens) is distributed up to 2400 m along the Fujinomiya road to Mt. Fuji. Along the road, we collected 75 adult plants from five populations at widely different altitudes. These plants are considered as a suitable material for analyzing the patterns of inter-population variations in plant architecture, biomass allocation and clonal growth pattern. In this paper, the following three hypotheses were tested using the common garden technique : (1) High-altitude population is likely to grow to be compact stature. (2) Five populations may show different biomass allocation patterns, which may be closely related to their altitudes ; High-altitude population may show larger allocation to roots but smaller to flower-heads and leaves including petioles than low-altitude population. (3) The populations may show different clonal growth patterns ; The plants from high-altitude, population may have many small stolons by which they form a phalanx growth pattern, whereas those from low-altitude population may have a small number of stolons with large size by which they form a guerrilla growth pattern. The results strongly supported the above three hypotheses. Mechanisms behind the between-population differences are also discussed.

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Aneurolepidium chinense has two ecotypes, the grey type and the green type. It has been reported that the former is more tolerant of saline and drought condition and grows on more alkaline and drier soil than the latter. This paper deals with soil alkalinity of these ecotype habitats. The vegetation and soil hardness, pH and electric conductivity (EC) were surveyed in two pastures. In one pasture (pasture A), the survey was made into six vegetation types that were concentrically distributed around an alkali-spot. The soil hardness, pH and EC were respectively 27 mm/cm^2, 9.5 and 0.222 mmho/cm in the grey type vegetation, and 15 mm/cm^2, 8.2 and 0.105 mmho/cm in the green type vegetation. In the other pasture (pasture B), the soil hardness, pH and EC were respectively 21 mm/cm^2, 9.8 and 0.098 mmho/cm in the grey type vegetation, and 5 mm/cm^2, 9.6 and 0.052 mmho/cm in the green type vegetation. From these results, it was concluded that the habitats of the two ecotypes were clearly segregated from each other by the soil alkalinity.

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We evaluated the productivity, wet endurance and adaptability to waterlogging of tropical forage legume, Aeschynomene americana cv. Glenn. Glenn was grown in pot under constant temperature of 25℃ and imposed four different durations of waterlogging i.e. 0 (no waterlogging as control), 10, 20 and 30 days. The treatment was started on the 14th day after germination. At the end of respective periods of waterlogging, pots were drained and thereafter held on the same condition as control until the 40th day after the start of treatment. Plants were collected at the start of treatment (0), 10, 20, 30 and 40 th day and measurements of dry matter yield, nitrogen fixation activity and nitrogen content of plants were conducted. Total non-structural carbohydrates (TNC) contents of plants on the 40th day were also determined. Plant growth showed a small decrease with 10 days of waterlogging treatment, but increased with longer waterlogging treatments comparing with control. Drainage following waterlogging increased plant growth. Results of growth analysis revealed that net assimilation rates (NAR) in all waterlogging treatments were higher than those in control. Under waterlogging condition, enhanced rooting and nodule formation on basal stem were observed. Nitrogen fixation activity, nodule number and nodule dry weight in all waterlogging treatments were higher than those in control during the experiment. Nitrogen contents and TNC contents in plants under all waterlogging treatments were significantly higher (p<0.05) than those in control.

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The field drying model was developed to predict moisture content of various types of wilted grasses suitable for big bale wrapped silage so as to evaluate harvesting systems. The drying model was based on experimental drying process data of conditioned Sudangrass (Sorghum sudaense (piper) Stapf.) on a field. Potential evaporation derived from Penman's formula most contributed to the fitting of regression curve and the coefficient of the exponential curve between moisture content and the accumulative Penman potential evaporation defined as drying coefficient. It depends on swath density, sectional area of the stem, mechanical treatment and the wilting methods. The predicted drying coefficients were validated by comparing predicted and actual field wilting data. The regression coefficient (the constant term set to zero) between the two coefficients was 0.946, and the correlation coefficient was 0.587. This mathematical model was assumed effective to predict the real time drying process for various type of silage grasses up to around 50% of moisture content (w.b.).

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We examined into propagation of morphogenic calli and preservation of regenerable capability through long-term culture using seeds of 9 cultivars and cv. "Nosappu" mature embryo in timothy (Phleum pratense L.) as explant. Seed callus was induced in modified Shenk and Hildebrandt (SH) medium (300mg/l NH_4H_2PO_4 in SH inorganic salts was substituted to 355mg/l KH_2PO_4 and 210 mg/l NH_4NO_3, and containing 2% (W/V) sucrose) supplemented with 0.5 mg/l 2,4-D or 0.5 mg/l 2,4,5-T. And mature embryo callus was also induced in modified SH medium supplemented with 0.5 to 2.0mg/l 2,4-D. Both in seed and in mature embryo, secondary propagated callus in morphogenic appearances was detected on primary callus. That had been the source of the callus propagation and plant regeneration. Regenerated plants were able to be transplanted directly into the soil without any acclimatization.

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We investigated the effect of application of a large amount of nitrogen fertilizer (e.g. 60kgN/10a) on the content of nitrate nitrogen of corn at the yellow ripe stage. We applied a large quantity of nitrogen using the chemical fertilizer more than the amount of nitrogen absorbed by corn, and we cultivated the plant in the field, where nitrate nitrogen was much abundant for the growth. It was not found that the content of nitrate nitrogen was more than 0.2% based on the dry matter at the yellow-ripe stage. The reason is due to that nitrate nitrogen was diluted by dry matter. Because dry matter was highly accumulated in the grain and stem at the yellow-ripe stage, on the other hand, most of nitrate was contained in stem and the capacity of accumulating nitrate nitrogen did not change. The difference among cultivars in the concentration of nitrate nitrogen based on the dry matter was highly correlated with that in the concentration of nitrate nitrogen based on the fresh weight in stem.

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