In order to investigate the influence of inoculation with lactic acid bacteria (LBA) and moisture level on the fermentative quality of silage exposed to air before ensiling, fresh and wilted Guineagrass (experiment I) and fresh sorghum (experiment II) silages were prepared in one litter experimental silos and stored at 28℃. After 30 days storing.the silages were analized and following results were obtained. 1. By means of exposure to air, moisture content incresed and water soluble carbohydrate (WSC) decreased in all materials. 2. In experiment I, the fermentative quality of aerated silage of all treatments (with or without LAB and wilting) gave higher pH and larger amounts of volatile fatty acids than that of control. And the quality of high moisture silage were better than wilted silage in the condition of exposure to air. The effect of inoculation with LAB on the quality of aerated silages, however wasnot observed. 3. There was no effect of exposing to air on the quality of the silages in experiment II, and the silages were good quality containing only lactic acid and acetic acid. 4. The silages in experiment II contained large amounts of mannitol in contrast with that of expriment I which hardly contained WSC.

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This experiment has following two aims. First one is to develope a rapid and simple enzymatic method for the determination of feed cell wall. Second one is to develope an enzymatic digestion method having a high accuracy in TDN prediction of hay and silage. Enzymes, source organisms were α-amylase (Bacillus subtilis), actynase E (protease from Streptomyces griseus), panchdase HP (protease from Aspergillus oryzae) and cellulase for feed analysis (Trichoderma reesei). The materials examined here as feed samples for cell wall determination were five corn silages, sorghum silage, barley, wheat bran and fecal samples when corn silages were fed. Potato starch and soybean meal were supplied as standard samples of starch and protein. Cell wall materials such as xylan, cellulose, isolated cell wall derived from grass and legume were also used to determine the cellulase and hemicellulase activity of enzymes. Furthermore, sixty five forages (hays and silages) were used to TDN prediction. Samples containing starch gelatinized firstly and then incubated with enzyme solution for 16 hr. at 40℃. Enzymatic system tried here were as follows ; 1) Two step method with α-amylase and actynase : At present, this method is used in Japan as ordinal enzymatic analysis of feeds. In this system, starch and protein digestion were carried out separetely. Therefore, two days need for analysis. 2) One step method with mixed enzymes : Sample was digested with enzyme mixture of 0.0025% (W/V) α-amylase and 0.025% (W/V) actynase. Enzymes were dissolved into pH5.8 acetate buffer solution containing 40ppm calcium acetate. 3) Panchdase-cellulase system : Sample was digested by 0.125% (W/V) panchdase and 1.0% (W/V) cellulase. Enzymes were disssolved into pH 4.4 acetate buffer solution. The main results obtained from these experiments were as follows : 1) In comparison of two step method and one step method concerning determined cell wall contents, there were no or slightly differences. And a time needed to analyze the cell wall was shorten by 24 hour by using a one step method. 2) High correlations were obtained between in vivo TDN and dry matter digestibility by panchdase and cellulase (DPC) in grass hays and grass-legume (alfalfa) mixed silages.

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Experiments were carried out to determine the changes of chemical composition of plant parts and cell wall degradability of stem in Sesbania cannabina PERS. with advancing maturity. The results obtained were summarized as follows : 1. The contents of organic matter (OM), organic cell wall (OCW), acid detergent fiber (ADF) and acid detergent lignin (ADL) of stem increased and ADF, ADL of leaf and crude protein (CP) and water soluble carbohydrate(WSC) of stem inversely decreased with advancing maturity. The contents of OM, OCW, ADF and ADL in stem were higher than those in leaf. The content of WSC of whole plant was ranging from 6.1-7.8%. 2. The content of Ca, Mg, P and K in stem decreased with advancing maturity. The higher content of Ca, Mg and K were measured in leaf than in stem, and the Na content was higher in stem than in leaf. 3. The contents of aspartic acid (Asp) in total nitrogen of stem and of whole plant increased and methionine (Met) in leaf inversely decreased with advancing maturity. The contents of Asp and glutamic acid (Glu) of leaf and of whole plant were the highest, followed by Leucine (Leu), and the contents of Asp in leaf and pod with seeds were highest, with decreasing order of Glu and Leu. 4. Cell wall degradability of stem by cellulase decreased with advancing maturity. 5. Therefore, we thought that, for the nutritive value of Sesbania, it is the better way to cut an early stage which was relatively low in fiber content. And it was suggested that the amino acid composition of Sesbania was generally the same as alfalfa except Met.

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High temperature and high moisture content of forage may affect disadvantageously the silage loss as well as the fermentative quality. Italian ryegrass, the most widely used winter crop for silage in south-west Japan, is often ensiled and stored under such condition. This experiment was carried out to estimate the in-silo losses from high moisture Italian ryegrass silage stored under high temperature conditions. At the ensiling time (14 May), the nylon-net bags, each containing 1kg of raw material, were placed in the middle of the trench silo, and were removed when the unloading procedure reached the bags. The temperature of silage was found to be high (39-42℃) in the top part of the silage pile and was lower (31-33℃) in the bottom part after opening the silo (25 July-12 August). The chemical composition of the silage was typical for silage of a high moisture content with no obvious aerobic deterioration. The dry matter loss (20%) and the losses of proximate components were not especially high, compared with the data reported in the past. The losses of cell wall constituents were relatively low (NDF ; 14%, ADF ; 8%, Cellulose ; 10%, Lignin ; 10%, Silica ; 9%), except for hemicellulose (22%). The losses of hemicellulose monosaccharides were not uniform, that is, 14% loss in xylose, 25% in uronic acids, 30% in arabinose, 42% in galactose and 52% in glucose. There were no differences in in vitro digestibilities between the raw material and the silage.

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Prairie grass (Bromus willdenowii KUNTH cv. 'Grasslands Matua') is a highly productive grass species with natural reseeding habit. Under Japanese grazing conditions, however, its persistence is poor. In this study, a new pasture management was tested on a prairie grass pasture to enhance the persistence of the grass by combining hay making in spring and rotational grazing in summer in order to take advantage of the natural reseeding process. A 0.28 ha prairie grass pasture was established in September, 1987, as a part of a 2.0 ha pasture. In 1988, the prairie grass pasture was grazed rotationally from spring until autumn, together with the other 1.72ha pasture. In 1989 and 1991, the prairie grass pasture was harvested on May 24 in order to make haylage, and then grazed rotationally until autumn. In 1990, the prairie grass pasture was grazed in early April, harvested on May 19, and then grazed rotationally. In 1990 and 1991, the number of seeds produced, seeds fallen and seedlings germinated from them was measured under the dual usage regime. In the tested pasture, the density of prairie grass decreased from spring to autumn. In autumn, however, the density recoverd as a result of the recruitment of natural reseeded plants. These reseeded plants contributed to maintaining productivity at a high level; the annual dry matter yield amounted to 8,670-12,800 kg/ha. Prairie grass began heading and anthesis in late April and mid-May, respectively, and this reproductive stage continued until August. When the pasture was harvested ten days after anthesis in late May, 1991, enough number of viable seeds fell during harvest and they established a good stand. On the other hand, when the pasture was cut earlier in 1990, the number of fallen viable seeds and seedlings was lower. The number of seeds produced was large in late May (at haylage making) and in July (under grazing). 83% of the seeds produced was fallen at haylage making, while only 12-14% of seeds was fallen under grazing. Although germination of the seeds fallen began from July, the seedlings could not survive during summer. Only seedlings germinated in autumn established a good stand. Following the decrease of the number of individual prairie grass plants during summer, fmgergrass, Digitaria adscendens invaded the pasture. Trimming of the pasture in mid-September not only helped to suppress fmgergrass but improved the light conditions for the seedlings which germinated after the trimming. From these results, we concluded that a permanent prairie grass pasture could be maintained when the pasture was (i) harvested after seed ripening (ten days after anthesis), (ii) grazed rotationally during summer, and (iii) trimmed in mid-September.

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The morphological components (leaf blade, leaf sheath, and culm content) of straw from 26 rice (Oryza sativa L.) cultivars was determined, and various quantitative anatomical features, including the proportion of internode area occupied by specific tissues and staining reactions for lignin, were made using scanning electron microscopy coupled with image analysis and light microscopy. Values obtained were related to the dry matter degradability of the straws and their botanical fractions. The greater degradability of rice straw was related to its higher culm content, and the inherently greater degradability of its culm fraction. The differences in culm degradability were also more pronounced than those in leaf degradability. Substantial degradation of the internode tissue was observed with disruption and erosion of less-lignified ground parenchyma cells, but more lignified vascular bundle remained intact. The proportion of tissue area occupied by ground parenchyma was positively related to the culm degradability, while negatively related to that of vascular bundle. These observations suggest that the differences in dry matter degradability were closely related to variations in the composition and degradability of stem fraction, variations in tissue area of specific cell types, and the inherent differences in the degradability of different cell types.

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Angle iron posts are sometimes used as materials for low cost fences. However, it is not clear whether angle iron posts can be used for fencing instead of the manufactured steel posts. The experiment using three types of post section with 3×30, 3×40 and 4×50mm angle iron posts was carried out on two pastures with different bearing capacity. Each experimental fence had 4 spans with a 4m post-interval, with the driven depths of 55 and 65cm and the plane angles of 60, 90 and 120 degrees between both sides of two spans, respectively. While loading the concrete weights on the wire to simulate snow loads, the lean of the corner posts was measured at 110cm height up to 10 degrees. The soil bearing capacity from the surface to 30cm in depth was less than lOkgf/cm^1 in the soft pasture ground but over 15kgf/cm^2 in the hard pasture ground. From the relationship between the load and the lean of corner posts, the larger post type needed more weight than the smaller one to achieve the same lean as the corner post. The post lean is mostly related to the load, causing it to bend, and the hard pasture ground allowing the corner post to lean less than in the soft pasture ground. Thus, in order to obtain a larger bearing capacity for the corner post, not only is a larger post necessary but also harder ground. Furthermore, in the soft pasture ground the smaller post has a similar lean independent of the difference in depth, and the larger post type leans less in a 65cm depth than in a 55 cm depth. On the other hand, the effect of the driven depth on the corner post lean was little or negligible in hard ground. In the case of plane angle, the softer the pasture ground, the more the corner post with a small plane angle leans. As a result of the experiment, we can recommend 4×50 mm angle iron post as fence material because of its stability. However, in the case of using angle iron posts, we must think about the durability for the rust on posts because of no painting, and about the easy fence maintenance without the snow damage in snowy areas.

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In order to account for the utilization of the pasture comprising both a native area and an improved area, the grazing behavior of breeding Japanese Brown cows was investigated in relation with quantitative and qualitative factors of herbage in the pasture. In the experiment-I, the pasture was rotationally grazed four times from May to September to comprehend the fundamental patterns of time spent grazing of the cows between both areas. On the other hand, the experiment-II. was carried out to clarify further the results obtained in the experiment-I. For the most part in the experiment-I, the time spent grazing per day was higher on the improved area than on the native area in the early stage of an experimental grazing period. Then, the time spent grazing per day on the improved area reduced, whereas the time spend grazing per day on the native area conversely increased and became longer than that on the improved area in the latter stage of the period. Ratios of the herbage allowance (HA) on the improved area to that on the native area (HA ratio) decreased during the grazing periods. The HA ratio was positively correlated with the time spent grazing on the improved areas. And the HA ratio was negatively correlated with the time spent grazing on the native area. On the other hand, there was an exception that the time spent grazing per day on the native area was longer than that on the improved area ab initio of the grazing period in May. This was probably caused by that the nutritive value of herbage of native area in this season was higher than that in another season. In the experiment-II, similar results as the general trend obtained in the experiment-I were observed when the HA summed both areas was much. When the HA reduced to an amount lower than the daily requirements for maintenance of the cows, the time spent grazing per day on the native area was retained the same degree as the previous length, but the time on the improved area increased again. These results suggest that the cows find the advantage on the herbage of the improved area as the acceptable canopy structure of the community for grazing, the high dry matter digestibility etc. under the severe quantitative condition of herbage.

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Morphological and phyllochronic shoot development in reed canarygrass (Phalaris arundinacea L., cv. Venture, RCG) and orchardgrass (Dactylis glomerata L., cv. Aonami, OG) seedlings was studied under an outdoor condition during May to early July, 1989. Both seedlings were culitivated in 8.5 cm pot, irrigated with HOAGLAND'S solution, and harvested at each of the leaf expansion ages 5, 7, 9, and 11 (developmental ages when 5th to 11th leaves just fully expanded) on main shoot, and length and dry weight of successive leaf blade, sheath and internode of main shoot were measured. Dry weight of root and tillers was also measured. 1) The successive leaf on main shoot of RCG plant expanded very quickly with the interval around 3.3 days/leaf, whereas expansion of OG leaves was in slower rate (Table 1). Tillering was rather regular in lower nodes of main shoot of both RCG and OG at the beginning of the observation, but the growth of higher nodal tillers (1st order) was gradually suppressed as seedlings grew and expanded higher leaves. Tiller emergence was completely suppressed in the axil of 7th main shoot leaf and above in RCG plant, on the contrary tillering suppression was lenient in OG. 2) The exponential growth of each organ in main shoot and whole plant was observed both in RCG and OG seedlings (Fig. 1, 2). The growth rate of RCG was kept higher than that of OG in each component of main shoot and primary tiller. These higher growth rate of RCG seedlings was derived mainly from its higher leaf area ratio (LAR) during early stage of seedling growth, being additionally followed by acceleration in net assimilation rate (NAR) in later stage when internode elongation was commenced. Higher relative growth rate (RGR) of RCG seedling was most prominent in internodes, especially in main shoot (Table 2). 3) Length of successive leaf blade and sheath and width of leaf blade on main shoot increased with acropetal succession both in RCG and OG (Fig. 4-A, B). Successive increment of leaf blade was much prominent in OG shoot, being accelerated on the upper nodes. Although successive increment of leaf blade width in RCG was much larger than OG, length enlargement was rather in slow pace and attained maximum size around the phytomers 10-11. Successive leaf area (calculated after KEMP'S Method ; leaf length×leaf midwidth×0.905) was larger in RCG than in OG, especially on the upper nodes (Fig. 4-C). No internode elongation was commenced at any stage of OG seedling growth, whereas internodes around the phytomers 6-7 began to elongate at the stage of 7th leaf expansion on main shoot (Fig. 4-D).

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To investigate the effects of Urea treatment of Guineagrass (Panicum maximum JACQ.) cultivar "Natsukaze" on nutritive value, the digestibility, nitrogen balance and blood metabolites in goats of urea-treated grass, treated with 36g urea kg^<-1>fresh matter of material (75.8% DM) and low-moisture (L-M, 71.7% DM) silage of the same material given alone or supplemented with urea were measured in a Latin square design study. The urea-treated grass contained more CP (18.0%) and less NDF (68.0%) than L-M silage. Digestibility of CP (62.5%) and NDF (63.5%) were significantly higher for urea-treated grass than for L-M silage (51.5%, 57.5%) or urea-supplemented L-M silage (50.6%, 56.2%). Urea supplementation of L-M silage had no significant effect on digestibility. Urea treatment increased significantly DCP value (11.3%) and slightly TON value (49.6%). Although nitrogen balance were not affected by treatment, fecal nitrogen of goats fed urea-treated grass was higher than that of goats fed urea-supplemented L-M silage, suggesting that some of added urea nitrogen was tightly bound to the material. Serum ammonia nitrogen concentration at 3hr. post feeding were 200μg/dl for urea-treated grass and 220μg/dl for urea-supplemented L-M silage significantly higher than for L-M silage alone. Plasma albumin at prefeeding was elevated significantly in goats fed on urea-treated grass and showed same trend at post feeding.

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Four technological assessments were conducted as fundamental study for development of selection method on the breeding of Italian ryegrass (Lolium multiflorum LAM.) for wet endurance. The results obtained are summarized as follows : 1. Evaluation of wet endurance by principal component analysis (Expt 1) : The principal component analysis was applied to find out important component using nine characteristics data of seedlings of twenty cultivars and strains after flooding treatment. The first principal component was considered as a good indicator of wet endurance. High correlation was recognized between the scores and dry matter yield on lysimeters under flooding condition. Therefore it was concluded that the first principal component score is quite suitable for the evaluation of both wet endurance and dry matter yield. 2. Simple method for the evaluation of wet endurance (Expt 2) : The degree of rooting on soil surface was correlated significantly to the first principal component score in the flooding experiment. A high correlation was also observed between the degree of rooting and relative dry matter weight (flooded/unflooded) of upper layer's roots after flooding treatment. Thus, the degree of rooting was considered as a more simple method than the component analysis using many variables for the evaluation of wet endurance. 3. Change of ventilating system of root after flooding treatment (Expt 3) : To examine relations between wet endurance and development of aerenchyma, intercellular space of root tissue was observed under a microscope. Cultivars classified into wet tolerant group by principal component analysis showed increase of the proportion of intercellular space in flooding condition. 4. Changes of alcohol dehydrogenase (ADH) isozyme after flooding treatment (Expt 4) : Five bands were detected on the zymograms of ADH extracted from root of non-flooded seedlings, while two bands with lower molecular weight than above mentioned bands were recognized only in flooded seedlings. These changes of ADH isozyme activities may be important in the physiological adaptation to wet conditions.

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We examined inter-patch variation in the degree of seed-set and seed size of white clover (Trifolium repens) in a T. repens-Zoysia japonica coexisting sward. Following questions were addressed : How efficiently does T. repens set seeds in this sward? Are there any differences in the degree of seed-set and seed size among T. repens patches and at different flowering times? If so, what features of patch will account for the differences ? Three classes of flower-heads distinguished according to their flowering time were collected at random from ten patches in the sward. They were measured for their number of florets, the number of seeds produced, the number of seeds per each pod, seed weight and peduncle length. Average number of seeds per pod was 1.31±0.31 (mean±SD) pooled over all patches, ranging from 0.92 to 1.83. The percentage of florets containing one or more seeds (fruit set) and florets containing three or more seeds were 68.8±10.2% and 16.3±8.3%, respectively. Significant differences in seed-set and seed size were found among the patches and among the flowering classes. Inter-patch differences in seed-set had no significant relationship with features such as patch size and average size of flower-head. However, it had a significant relationship with the average peduncle length of patch, suggesting the possibility of patch selection by pollinators. Patterns of the differences among the flowering classes were so complex. These findings showed that the patches differed considerably in the extent to which they contributed to seed number and quality of the entire sward. They also suggested that spatiotemporal patterns of T. repens seed-set in this sward may be partly related to the nature of polination behavior of honeybees and bumble bees.

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Single application of fertilyzer in spring on orchard grass (Dactylis glomerata L. cv. KITAMIDORI) cultivation was studied using controlled release polyolefin coated urea (POCU) to conduct labour saving and to maintain stable plant density. Field experiment was carried out on Kawatabi Andosol in 1988 to 1989. The following three treatments were designed. Conventional plot: 4 times application of N fertilyzer (10-8-4-2 gN/m^2), coated urea plot: single application of N fertilyzer (20gN/m^2 of POCU, LP100 and 4 gN/m^2 of urea and-N plot : none application of N fertilyzer. 1) A relationship between days calculated as 25℃ after application (X) and cumulative percentage of nitrogen release from POCU,LP100 (Y) was expressed by the following equation. Y=0.759X+4.67(r=0.988^<***>, n=9) There was a quite high correlation between these two factors. However, the release rate of nitrogen from LP100 applied at the surface of grass land was about 30% faster than that applied in plow layer. 2) The relative dry matter yields of orchard grass of conventional plot, coated urea plot and -N plot were 100, 110-111, and 55-83, respectively. They were closely related to both leaf color index and amounts of nitrogen absorption. 3) The recoveries of N fertilyzer of plant both in conventional and coated urea plots were calculated by substructing the amounts of nitrogen uptake in -N plot. These recoveries were 53% and 68%, respectively. Therefore, recovery of coated urea by plant seemed to be much higher than that of urea. 4) We may conclude that single application of nitrogen fertilyzer in spring using POCU is one of the most feasible methods judging the matter from the viewpoints of the labour saving, high yielding, envirmental conservation, etc.

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Percent Brix of stalk juice has been proposed as a trait for evaluating indirectly stover digestibility of corn. However, it is essential to establish the best portion of the stalk for efficient evaluation of the percent Brix of stalk juice in breeding materials. In addition, it is important to clarify the effects of correction for the measurement of percent Brix by stalk dry matter content. For these purposes, internodal variations in percent Brix of stalk juice and estimated stalk sugar content (ESSC) in three experimental hybrids with large differences in percent Brix were analyzed with special reference to genotypic differences and experimental error. The ESSC of each internode was calculated as follows. ESSC(%)=[(FW-DW)×Percent Brix/{(100-percent Brix)×DW}]×100 where, FW=fresh weight, DW=dry matter weight. Percent Brix and ESSC increased from the lowest internode up to the one just above the top ear and maintained almost constant values above it. For both traits, differences among hybrids varied corresponding to the internodal variations and reached the maximum at the internode just above the top ear. LSD_<.05> for both traits at internodes above the top ear were smaller than those below it. Among hybrids, the differences in dry matter content at respective internodes were smaller above the top ear than below it. Coefficient of variation in percent Brix was smaller than that in ESSC except the four bottom-most internodes. Variations in ESSC followed a pattern similar to those of percent Brix among internodes and hybrids. The effect of correction of percent Brix by stalk dry matter content was not recognized within the range of genotypes used in this study. From the above results, it was concluded that the internode just above the top ear is most suitable for measurement of percent Brix as an indicator of stover digestibility.

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