A series of laboratory experiments was carried out to evaluate the inherent anchoring function of coleorhiza hairs of surface-sown forage grasses. The direct-penetration ratio of seminal root (DPR) and the adhering strength of coleorhiza hairs of surface-sown seeds, and number of hairs of germinating seeds in water was examined for fifteen pasture plants, six soiling crops and five native grasses. 1) The grass species examined were classified into three groups according to the DPR and adhering strength of coleorhiza hairs. Group A : Tall fescue, coloured guineagrass, finger millet and native grasses produced over 160 coleorhiza hairs and anchored to the soil surface with adhering strength above 2g, resulting 50% higher of DPR. Orchardgrass and Kentucky bluegrass produced a small number of hairs, and timothy and bermudagrass far less in number and in adhering strength among species examined, but they reached more than 50% of DPR. Group B : Italian and perennial ryegrasses, meadow fescue, green panic and three millets produced 40-110 hairs and showed 0.5-1.5g of adhering strength, DPR being 20-40%.

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Nine hays with neutral-detergent fibre (NDF) and acid detergent fibre (ADF) concentrations ranging from 462 to 739 and from 319 to 447 gkg^<-1> dry matter (DM) respectively, were used to assess the possibility of predicting voluntary DM intake (DMI), apparent DM digestibility in vivo (DMD) and digestible DM intake (DDMI) by sheep from the rumen degradation characteristics represented as a rate and potential extent of degradation of the hays, outflow rate (k_1) from the rumen and rumen fill (Rf). Three sheep were used repeatedly for each hay in all the measurements. The degradation characteristics were measured by incubating samples in polyester bags in the rumen and the water soluble fraction (A) was measured. The exponential equation p=a+b(1-e^<-ct>) or p=A+B (1-e^<-ct>) was fitted to the results. Outflow rates (k_1) were determined by using Cr mordanted fibre prepared from each hay. Rf was given by the equation Rf=m/(c+k_1)+n/k_1(m=(a+6)/100, n=1-(a+6)/100). There were large differences in the DMI and DDMI measurements of hays varying from 40.4 to 84.8 and 21.4 to 50.3g day^<-1>kg^<-1>LW^<0.75> respectively, with wide variations in the degradation rate (c), solubility (A) and potential degradability (defined as a+b), k_1 and Rf. The Rf was highly correlated with the DMI (r=-0.928; P<0.01). The inclusion of K_1 or Rf with a, b and c or A, B and c in multiple regression to predict DMI, DMD and DDMI gave better results than when lag time for degradation (Lt) or NDF were used instead of k_1 or Rf. Consequently, the use of a, b, c and k_1 in a multiple regression equation gave the most precise prediction of DMI and DDMI having coefficients of determination R2 = 0.979 (residual s.d.=2.99g day^<-1> kg^<-1> LW^<0.75>) and 0.972 (residual s.d.=2.56g day^<-1> kg^<-1> LW^<0.75>), respectively. These results indicate that the accuracy of DMI and DDMI pre-dictions of hays may be improved distinctly by using k_1 or Rf with the rumen degradation characteristics.

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As a fundamental step for studying the biochemical properties of grass lipids on ruminal fermentation and digestion, this experiment was carried out to investigate the changes in the amount of lipid fractions and fatty acid composition attributed to hay making. The first growth of orchardgrass sward harvested at early heading stage was used for fresh sample and sun-cured hay sample. The lipids were completely extracted from the fresh and hay samples with chloroform-methanol (2:1, v/v). The total lipids were separated into four fractions viz. polar lipids (PL), free fatty acids (FFA), triglycerides (TG) and sterol esters (SE) by thin layer chromatography. For each lipid fraction, the composition of the individual fatty acids was analyzed by gas chromatography. The amount and molar percentage of PL fraction decreased significantly for hay, followed by an increase in FFA fraction. The amount of total and individual fatty acids (particularly for polyunsaturated acids) of total lipids tended to decrease due to hay making, but these changes were not remarkable. The fatty acid composition of FFA fraction showed that the molar percentages of linoleic and linolenic acids increased drastically, while those of palmitic, stearic and oleic acids decreased for hay. These results suggest that the decrease in concentration of PL fraction during hay making was closely associated with the increase in concentration of FFA fraction and that an increased proportion of polyunsaturated fatty acids in FFA fraction could be attributed to hay making.

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The zoysiagrasses are indigenous to Japan and are distributed nationwide with wide variation of growth characteristics. The temperature responses of photosyn-thesis among seven strains of zoysiagrasses from different origins were studied using the plants grown for a week with gradual decrease of the growth temperatures (35/30℃ to 10/7℃). The CO_2-saturated O_2 evolution and chlorophyll fluorescence (Fv/Fm) were measured at 25℃. A large interstrainal difference for the photosynthetic O_2 evolution were observed on the zoysiagrasses grown under low temperatures. Such variations were correlated with the inhibition of PSII estimated from the changes of chlorophyll fluorescence (Fv/Fm). However, these photosynthetic susceptibilities to low growth temperatures of seven zoysiagrsses were not related to the climatic condition of the provenience districts of strains. The results suggest that the photosynthetic sensitivity to low growth temperatures is not the main factor to deter-mine the northern limit of the growth of strains.

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Variation in seed germination pattern of Poa annua L. within populations was studied for 14 populations from two golf courses, a paddy and an upland field under light and dark conditions. Germination tests were performed for 30 days at 20℃. Based on the variation in germination pattern within populations, 14 populations were divided into four groups: (A) Seeds of most individuals germinated quickly and almost completely. (B) Seeds of individuals quickly germinated, but varied in cumulative germination. (C) Individuals showed wide variation both in cumulative germination and time to germination. (D) Seeds of most individuals scarcely germinated. Al-though the germination patterns of golf course populations in the light and the dark greatly varied from Group B to D, reddish plants from greens were in contrast to non-anthocyanic ones from the same greens in germination behavior. Seeds of reddish green plants strongly required light intensity to germinate while non-anthocyanic ones exhibited good germination even in the dark. The strong light requirement of reddish plants for germination appeared to be adaptive to hand weedings in green. Individuals from tee grounds, fairways and roughs were variable in germination traits.

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Vegetation of Miscanthus-type grassland located in Kanto region of Japan and subjected to artificial pressure such as cutting, burning, and grazing were investigated in the fixed quadrates for 20 years. Community data, as represented by the extended summed dominance ratio, E-SDR2, was ordinated by principal component analysis. The first component, characterized by Miscanthus sinensis and Zoysia japonica, indicated the effect of grazing. The second component, characterized by trees, indicated natural succession. Yearly vegetational data for each plot was plotted on these two component axes. The vegetation of each plot was distributed depending on the kind of artificial pressure.

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In general, under grazing conditions, the vegetation on Miscanthus-type grassland will change on Zoysia-type grassland. The change rate of vegetation from Miscanthus-type to Zoysia-type vegetation were described by change rate of the extended summed dominance ratio, E-SDR2, of dominant species. In the kanto region, when dominance of Miscanthus sinensis reached a high level, the E SDR2 of M. sinensis fell depending on the grazing pres-sure. However, when M. sinensis was inferior, the E-SDR2 of M. sinensis fell depending on the grazing times. On the other hand, the E-SDR2 of Zoysia japonica rose under graz-ing. This method applied to Miscanthus-type grassland in the Tohoku region, and the dominance rate of M. sinensis under grazing compared with in the Kanto region. The decrease in the E〜SDR2 of M. sinensis in the Kanto region due to grazing was higher than in the Tohoku region.

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This study is focused on a subalpine grassland ecosystem characterized by Gramineous species in central Japan. The aim is to understand (1) the dominant species of this grassland and (2) how the composition of these dominant species changing with altitudinal gradient. Field surveys in Kirigamine grassland have been conduced for three years from 1992 to 1994. Results showed that (i) Kirigamine grassland was consist of tall-grass type communities characterized by Calamagrostis longiseta or Miscanthus sinensis, and partly by C. langsdormi. (ii) Along altitude changing from 1,500m a.s.l. to 1,900m a.s.l., vegetation changed continuously from M. sinensis grassland to Calamagrostis spp. grasslands in the investigated area. One species of C_4 grass, M. sinensis was the dominant species at lower altitudes, and Calamagrostis type vegetation, which was consist of many C_3 grasses, replacing M. sinensis gradually became dominant at higher altitudes, (iii) The study area was divided into two main slopes: westside and eastside slopes according to the main ridge that extended from Mt. Kurumayama to north. The transitional altitude from M. sinensis to C. longiseta community in westside main slope was about 100 m higher than eastside main slope. However, such difference was not found within each main slope, (iv) Comparing to the results of past surveys, the distribution of Sasa chartacea expanded markedly accompanying the decreases of Arundinella hirta communities and some species such as Scabiosa japonica, Aster scaber, Ligularia stenocephala and Lespedeza spp..

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Few information on the chemical constituents and the rumen degradation characteristics of cold weather-damaged rice straw (CDRS) was reported. The chemical composition, the 48 h dry matter loss (48h-DML), maximum potential dry matter degradability (MPDD) and degradation rate (DR) in the rumen of sheep were investigated for forty-seven samples of CDRS collectedin 1993 and their botanical fractions (leaf blade, leaf sheath and stem) showing different percentage of sterility and compared to those of the seven samples of normal rice straw (NRS) and their botanical fractions collected in Iwate prefecture in 1994. The stem tissues of CDRS and NRS were observed by a scanning electron microscopy. The proportion of stem in CDRS was increased, while those of leaf blade and leaf sheath were decreased with increasing the percentage of sterility. Differences in the proportion of the botanical fractions between CDRS and NRS were particularly larger in the stem and leaf sheath than in the leaf blade. Crude protein (CP) of CDRS increased with increasing the percentage of sterility, whereas neutral detergent fibre (NDF) was decreased, showing the maximum differences of 4.3 (CP) and 6.7% (NDF) units between CDRS and NRS. The concentrations of mono- and oligosaccharides and starch were less variable among the percentages of sterility of CDRS, but those were 1.8-1.7 and 5.9-4.3 times higher than in NRS, respectively. About 90% of the total amount of those constituents in the whole straw was attributable to those of the stem. Higher content of starch in stem was also consistent with observation of starch granule in the stem of CDRS with a scanning electron microscope. The increase of percentage of sterility gave higher 48-h DML and MPDD, and their differences between CDRS and NRS were 19.8-11.9% for 48-h DML and 20.4-12.6% units for MPDD. The 48-h DML of botanical fractions in CDRS was particularly high for stem (77.6-74.2%), followed by leaf blade (66.0-53.1%) and leaf sheath (56.8-55.2%) in which maximum differences compared to NRS were 12.8, 18.2 and 21.2% units, respectively. The DR of CDRS with high and middle percentage of sterility were increased ranging from 4.6 to 4.1%/h, respectively, while that of NRS was 3.0%/h. It was concluded that the chemical composition and the rumen degradation characteristics of CDRS were significantly varied by the extent of percentage of sterility which was associated with cold weather damage, and also the nutritive value of CDRS was remarkably higher than that of NRS.

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Avicelase (F1-3), xylanase (F1-5), pectinase (F5-1) and carboxymethylcellulase (CMCase) (F5-2) of Acremonium cellulolyticus Y-94(ACS2) were fractionated by anion-ex-changechromatography (Q Sepharose High Performance: Pharmacia) and hydrophobic chromatography (Phenyl Sepharose High Performance: Pharmacia) and investigated for their effect on fermentation quality of ensiling alfalfa. Each of the enzyme preparations simply showed a specific cell-wall degrading activity. Fresh alfalfa was cut and chopped to a 2 cm length and ensiled on treatments with avicelase and commercial lactate producing bacteria, alone or combined with each of the other enzyme preparations, for 14 days at 26℃ in nylon/polyethlene bags. Alfalfa ensiled with the F1-3 fraction produced more lactic acid than did the untreated one. Enhanced production of lactic acid in the F1-3 treated silages was observed for combined treatments with the F5-1 or F5-2 fractions, while the combination with the F1-5 fraction was less effective. Treatments with cellulases and pectinase used in this study can increase lactic acid production on ensiled alfalfa.

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Making silages with tropical grasses mixing with legume has a practical importance to improve the low nutritive value. Effect of the species and rate of mixing of legume on fermentative quality must be considered in making mixed silage. With the silage made using two tropical grasses, bahiagrass (Bg) and barnyard millet (Mi), and tropical legume, phasey bean (Pb) which is considered one of the tropical legumes producing well-preserved silage, the influence of mixing ratio of Pb on fermentative quality was investigated. The mixing ratios of Pb to Bg or Mi were 0: 100, 25: 75, 50: 50, 75: 25 and 100: 0 on fresh weight, respectively. After about 100 day storage in experimental silo under constant temperature of 20℃, chemical analyses were con-ducted. In all the silages lactic acid contents were not so high (0.5-6.0% DM) and pH did not decrease below 4.5. The higher proportion of lactic acid to total acids concentration and lower production of butyric acid in mixed silages compared to those of respective grass silages were observed, especially for the mixing ratios of 50: 50 and 75: 25. The amount of protein in the material increased by mixing with Pb. Although the quantity of protein degraded increased with increasing ratio of Pb to Bg or Mi, no significant effects on VBN production were observed. These results suggest that mixing Pb to Bg or Mi in making silage has an improving effect on the composition of organic acids and no adverse effect on account of VBN production.

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Three-month Feeding trials were conducted to investigate on the body weight gain and blood biochemical pro-files of Holstein steers fed on sesbania silages (S, cannabina Pers. and S. rostorata) as a roughage. The steers required to adapt for the sesbania silage rations and increased their intake up to 2 weeks. The daily gains of steers fed both sesbania silages did not differ from that of the control (alfalfa ration: Medicago satava L). No clinical signs of sesbania ill effect was evident in these steers during feeding period. Hematological profiles (Red blood cells, white blood cells, hemoglobin, Hematocrit values) and biochemical parameters (Glucose, Total-protein, Urea-nitrogen, Albumin and Globulin) in steers fed sesbania silages did not significantly differ from the control group. Serum enzyme activities (Glutamic oxaloacetic transaminase, Lactic dehydrogenase, γ-Glutamyl trans-peptidase, Creatine phosphokinase and Ornithine carbamoyl transferase) and serum mineral concentrations (Ca, Mg, K, Na and inorganic-P) in steers were not either affected by feeding with sesbania silages. Similar trend of urine profiles (pH, protein, glucose, occult blood, urobilinogen and white blood cells) in the steers fed on sesbania silages and control rations were also observed. These results suggested that sesbania silages could be used a roughage source for ruminants.

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Nutritive value, energy balance and rumen fluid characteristics in goats offered chopped (CR) or splited (SR) rice straw rations were measured. Both rice straw rations were added soybean meal in order to adjust to 12% of crude protein (CP) content. The CP and ether extract con-tent of rice straw tended to be decreased by the treatment of split, but there were no apparent differences in other constituents between the chopped and splited rice straws. The digestibilities of organic cell wall and acid detergent fiber of SR ration tended to be higher than those of the CR ration, while the content of digestible crude protein of SR ration was significantly lower than CR ration. The gross energy intake, digestible energy intake, metabolizable energy intake and methane excretion in SR ration were significantly higher than in CR ration. There were no significant differeces in heat production, energy retention and other energy measurements between CR and SR rations. In the rumen fluid characteristics, the ruminal pH value was lower and ammonia nitrogen and volatile fatty acid were higher at 4 hour after feeding than before feeding, but significant differences between CR and SR ration were not observed. It appeared that the treatment of split had an effect on feeding value of rice straw by increasing the energy intake more than by increasing the nutritive value.

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To standardize the criteria of forage quality of commercialized wrapped round-bale silage with containing low moisture content, fermentation profiles, indigestible intake protein and gross chemical composition were investigated on round-bale silages of timothy (Phleum pratense L.) and alfalfa (Medicago sativa L.). Variations in forage evaluation among sampling sites of baled silages were also examined to qualify the representative collection. The forage plants examined were harvested at three different growth stages; early, optimum and late cutting of the 1st harvest, and were milted to 30%-50% of moisture content in crop fields. 1. The mean concentrations of lactic, acetic and butyric acids in the wrapped bale silages produced were very low at 0.65%, 0.30% and 0.04%, respectively. The mean pH values of 5.48±0.22 also showed poor fermentation of the silages, suggesting that these fermentation profiles were not appropriate for standardizing the quality evaluation of the wrapped round-bale silages with low moisture con-tent. The indigestible intake protein, thought to be increased by heat damage during the storage, was not different between the original fresh crops and the corresponding silages. The contents of moisture, protein (CP), acid detergent fiber (ADF) and neutral detergent fiber (NDF), as already extensively used for evaluating nutritive value, appeared to be useful and simple indice to standardize the forage evaluation of those silages. 2. Effect of sampling site on variations of the contents of moisture, CP, ADF and NDF was investigated on twelve wrapped round-bale silages with varying forage crops, growth stages and wrapping film color. Among twenty-one points plotted equally in the wrapped round-bale silage, the sampling block of 30cm (from the top)×20cm (from the north and east side edges) was the best representative of showing the quality of the whole bale.

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