Effects of nitrogen fertilizer rate and cutting height on tiller dynamics in bahiagrass (Paspalum notatum Flugge) sward were investigated over a 4-year period. The treatments were combinations of 2 nitrogen rates [5 (LN) and 20 (HN) gm^<-2>year^<-1>]×3 cutting heights above ground level [2 (LH), 12 (MH) and 22 (HH) cm]. Total tiller density was ranked LH>MH>HH, and HN>LN in LH treatments. Tiller appearance rate (TAR) on a per unit ground area basis tended to be ranked LH>MH&ap;HH ; whereas that on a relative basis showed variable responses, often characterized by a trend of LH>MH&ap;HH in the first 2 years and LH<MH<HH thereafter. Increasing nitrogen rate often increased TAR on a per unit ground area basis in LH treatments, but had little effects in the other treatments. The effect of nitrogen rate on TAR on a relative basis appeared to be smaller and less consistent. The rate of site filling (the rate at which axillary buds develop into tillers in relation to the rate at which leaf axils are formed) decreased as herbage mass increased to a critical value, and remained almost constant thereafter. Tiller death rate (TDR) on a per unit ground area basis during summer to autumn was higher in HN/LH than in other treatments. Relative TDR increased exponentially with increasing mean daily air temperature. Tiller longevity tended to increase as nitrogen rate and cutting height decreased ; tillers in LN/LH treatment tended to survive longest (half-life=537 d) and those in HN/HH treatment shortest (half-life= 408 d). The results show that bahiagrass responds to low nitrogen and intense defoliation (low resource availability or severe management) with increasing tiller longevity, and tolerates intense defoliation also by increasing TAR per unit ground area, and thus tiller density.

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Leaf dynamics of bahiagrass (Paspalum notatum Flugge) swards in response to nitrogen fertilizer and defoliation were investigated for a 3-year period, in terms of number of leaves per tiller, rates of leaf appearance, death and detachment (as litter fall) and leaf longevity. The treatments were combinations of 2 nitrogen rates [5 (LN) and 20 (HN) gm^<-2> year^<-1>]×3 cutting heights above ground level [2 (LH), 12 (MH) and 22 (HH) cm]. The number of live leaves per tiller was almost similar among the treatments. By contrast, the number of dead leaves per tiller was ranked LH<MH&ap;HH. Leaf appearance rate was positively related to air temperature, and leaf death rate and detachment rate to the number of live and dead leaves, respectively. Leaves appearing in October survived longer (half-life=27-29 weeks) than those appearing in April-September (half-life=7-20 weeks). Leaf appearance, death, detachment and longevity were stable across the treatments, except that leaf death in LH treatments was depressed during the cutting season (May-October). This stability is in contrast to the fact that the nitrogen and defoliation treatments resulted in variation in appearance, death and survival of tillers and in the extension and mature size of leaves in concurrent companion studies.

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Leaf dynamics of bahiagrass (Paspalum notatum Flugge) swards in response to nitrogen fertilizer and defoliation were investigated for a 3-year period, in terms of extension and mature size of leaves (laminae) on tillers. The treatments were combinations of 2 nitrogen rates [5 (LN) and 20 (HN) gm^<-2> year^<-1>]×3 cutting heights above ground level [2 (LH), 12 (MH) and 22 (HH) cm]. Leaves extended most rapidly when they were the first and second youngest leaves, and almost stopped extending when they became the fourth leaves. Extension rates of the first leaves increased linearly with increasing air temperature. The second leaves extended proportionally to the first leaves, and the third leaves to the second leaves. Extension rates of all leaves increased as nitrogen rate and cutting height increased. Mature leaf size, i.e. the potential length of lamina, also increased with increasing nitrogen rate and cutting height, because rates of leaf appearance were constant across the treatments. The decreased rates of leaf extension yet the constant rates of leaf appearance under low nitrogen and intense defoliation (low resource availability or severe management) are considered to be effective in minimizing losses of leaves by defoliation.

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Four Holstein steers fitted with cannulae in the rumen and duodenum were grazed on orchardgrass (Dactylis glomerata L.) pasture to examine the effect of pre-grazing sward length and daily herbage allowance on ruminal nitrogen (N) digestibility and duodenal non-ammonia nitrogen (NAN) supply. Pasture maintained at two levels of daily herbage allowance of 50 and 100gDM/per kg BW of steers and two levels of sward length (35 and 25 cm) were allocated to four treatments in a 2×2 factorial design. N content of herbage did not significantly differ between sward lengths but declined when the daily herbage allowance was high (P<0.01). N intake increased in the short sward pasture than in the long sward pasture (P<0.05). However, the duodenal NAN flow was greater in the long sward pasture than in the short sward pasture (P<0.01), because the microbial N synthesis in the rumen and the ruminally undegraded N flow to the duodenum significantly increased in steers grazing on the long sward pasture (P<0.01). The amount of post-rumen N disappearance increased when steers grazed the long sward pasture compared with the short sward pasture (P<0.01).

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We examined effects of inoculation of a Lactobacillus corniformis strain which metabolizes glycerol into reuterin, an antimicrobial substance on laboratory-scale ensiling of rice straw. In these experiments, inoculation of the Lactobacillus corniformis plus glycerol of 1 to 2% fresh matter inhibited butyric fermentation of the silage even if its pH remained more than 5. During aerobic exposure of the silage inoculated with the L. corniformis plus glycerol, pH increase of the silage which was caused by lactate-utilizing yeasts retarded and mold growth on the silage also retarded. Addition of glycerol together with the L. corniformis was required to obtain these effects, which suggests that the effects were due to pro-duction of reuterin.

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Reflectance (R), polarized reflectance (Q) and degree of polarization (P) were measured for a mixed seeding pasture consisting of white clover (WC) and tall fescue (TF) in 8 spectral bands in the visible, near-and short-wave infrared wavelength ranges. The radiometer observed the reflected sunlight in a 10° field of view approximately1.6 to 2m apart from each grass canopy. The view zenith angles (Zv) were set from 15° to 75° at 15° intervals, and the observation azimuth was toward the sun. The highest correlation coefficients with the ratio of legumes (ROL, LAI ratio of WC to the total) were obtained for Q in the 660 and 2200 nm bands measured at Zv 60° when Q is multiplied by the cosine of solar zenith angle (Cos Zs) at the time of each observation. The second highest correlation was found between ROL and 660 nm band R with Zv 15°, but P and NDVI showed lower correlations. A multiple regression model that used a Q and 3-band Rs that were all acquired at Zv 60° explained 90% of the variation of ROL with RMSE 11%. Utilizing polarization information of reflected light is effective in estimating ROL of mixed seeding pastures where planophyll and erectophyll plant species coexist.

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Studies were carried out on the progress of dormancy awakening and changes of effect of light and alternating temperature on germination of Echinochloa crus-galli (L.) Beauv. and Digitaria adscendens (H. B.K.) Henr. buried seeds in the central highland area of Kyushu. Time of dormancy awakening was not different between shedding and adhesion seeds of both species. Buried seeds of both species remained in dormant during the season in which the environment was suitable for germinate in the soil, i. e., September and October. The dormancy was gradually awakened during winter. Over 85 percent of the seeds had come out of dormancy by May. Under preservative conditions of different temperature and moisture, progress of dormancy awakening was different. Chilling in moist condition promoted the dormancy awakening most, which maybe the most important environmental factor related to the dormancy awakening in winter. Effect of light and alternating temperature on germination was very different among various dormancy awakening phases. In the phase of deep dormancy no germination occurred under any conditions, but in the more progressed phase of awakening germination was promoted under light and daily alternating temperature conditions. Finally germination could be observed even under constant temperature and dark conditions in the completely awaked phase. Difference of dormancy awakening phase caused by various environmental conditions in the soil may be one of the factors that induce variation in germination time.

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Vegetation and yield changes in timothy (Phleum pratense L., cv. Hokushu) pastures over four years in an intensive grazing system (IGS) were compared with those of a timothy meadow managed by cutting three times a year (C). Both swards were established simultaneously and used for experimentation from the following year. We divided pastures into 35 paddocks ; 43% of paddocks (G) were grazed rotationally throughout the grazing season. Other paddocks (CG) were harvested for ensiling in early June ; they were then used for grazing with G through the grazing season. Grazing pressures of G and CG were 618 and 353 cow-days/ha/year, respectively. The meadow was harvested in early June, late July, and mid-September. Results were : (1) The timothy component of herbage in the spring of the 4th year were 84%, 73% and 54% in G, CG and C respectively. Some invading plants, e.g., kentucky-bluegrass and white clover, increased annually in all treatments. (2) Annual total herbage masses available for intake through the grazing season were estimated at 6,357 kg DM/ha in IGS and 6,633 kg DM/ha in C. (3) Herbage intake by grazing were estimated at 6,247 and 3,583 kg DM/ha in G and CG respectively. Total herbage intake by grazing in IGS, a weighted mean by area percentage, was 4,729 kg DM/ha.

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The bale wrapper which could wraps the round bales of 100cm diameter in especially under the soft and wetground in paddy field was developed. This bale wrapper is a self-propelling type with the rubber track and it is turn table and a single dispenser type of stretch film. This bale wrapper has the feature in the method of loading and unloading the bale. When this bale wrapper loads the bale, it employs a lifting-arm which lifts the bale from the lower part of the front side of the body. The method of loadingthe bale loads the bale by gripping it between the table rollers and the lifting arm. It is possible to work by following to the round baler because the bale in front of the body can be loaded. Especially, in a soft and wet paddy field the bale which the round baler (The cutting round baler for the rice whole crop silage) discharges can be received directly with the lifting arm. The wrapped bale is lowered to the ground in reverse procedure. Especially, when this bale wrapper unloads the wrapped bale on to a trailer, the wrapped bale with the turntable is lifted up bythe table lift, and is dumped to the front and unloaded. All these loading or unloading devices are driven by hydrauliccylinders. The working efficiency of this bale wrapper depend on the number of bales, and other conditions. When this bale wrapper moves from the levee to the bale, it loads the bale, it moves while wrapping (wrapping in 4 layers, with two cycles of 50% overlapping film width) and it unloads the wrapped bale, working hours was 33.5 minutes per 10a (Thenumber of bales : 9 bales per lOa). The fermentation quality of the wrap-silage was excellent, when the rice plant of 60% moisture content was baled and wrapped in 4 layers.

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The historical development of grassland and grassland systems in Europe is outlined and current methods of production and utilisation discussed. Grassland contributes about 60% of the nutrients consumed by ruminants, with grazing predominating during the growing season and hay and silage feeding during winter. There are economic pressures involving competition with other feeds, environmental pressures to reduce risks of pollution of water and the atmosphere and the quest to maintain and enhance biodiversity and landscape values. It is concluded that grassland will continue to be of major importance throughout Europe. The role of grassland for the provision of feed for ruminants may decrease, because of competition with concentrate feeds and other forages. Existing intensive systems will be adapted to reduce risks of pollution. The use of grassland for environmental protection and enhancement will be of increased importance with the management of substantial areas being targeted on biodiversity, landscape or water catchment.

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