Two types of plant succession have been known in native grassland under cattle grazing at Kawatabi farm. These are the changes from tall grassland dominated by Miscanthus sinensis to sod grassland dominated by Zoysia japonica and to shrub dominated by Weigela hortensis. The prediction of these succession types will be important because of getting an information of carrying capacity for grazing cattle in the future. In order to recognize the ground that these two types rise in under cattle grazing, we surveyed the depth of human layer and the coverage of dominant species in three native grasslands with a different grazing history at Kawatabi farm. Surveyed grasslands are named Ungrazed grassland, Grazed A (6 years grazed) and Grazed B (15 years grazed). Results are as follows. 1. There are close relationships between slope shape and the depth of humus layer. The depth of humus layer at the convex slope site was thin (25 cm-50 cm), and at the concave slope site was deep (50 cm-110 cm). 2. In the Ungrazed grasslands, Miscanthus sinensis dominated and partly Sasa palmata and W. hortensis. S. palmata distributed at the thin humus layer site and W. hortensis distributed at the deep humus layer site .3. The coverage of M. sinensis in Grazed A was lower than that in Ungrazed grassland. The plant community at the deep humus layer site of Grazed A was dominated by W. hortensis. Z. japonica distributed at some stands at the thin humus layer site. 4. Grazed B was dominated by Z. japonica and W. hortensis. The former only appeared at the thin humus layer site and the latter at the deep humus layer site. The native grassland under grazing shows a different types of plant succession between convex slope and concave slope. At the convex slope, tall grasslands dominated by S. palmata and M. sinensis changed to sod grassland dominated by Z. japonica. At the concave slope, M. sinensis community changed by grazing to shrub dominated by W. hortensis.

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Green juice extracted from adley (Coix lacryma-jobi L.), alfalfa (Medicago sativa L.) and Italian ryegrass (Lolium multiflorum LAM.) foliages with a twin roll screw press were dried with a spray-drier and their hypocholesterolemic activities were compared in rats. A part of the adley juice was heated to 110℃, kept for a few days at 85℃ and then dried the lower portion which included the heat-coagulable matters such as protein. The chemical composition of the dried green juice powders (GJP) were different and GJP from adley, alfalfa and Italian ryegrass were relatively high in minerals, nitrogen and crude fat, respectively. In rat trials, in order to make sure the effect of GJP on hyperfholesterolemia, diets containing 10-20% lipids, 1% cholesterol and 0.25 or 0.5% cholic acid with 20% GJP were prepared. As a controls diets containing 20% casein with or without cholesterol and cholic acid were used. The protein content of the diets containing GJP were adjusted to the control by adding casein. The rats fed on the casein diet including cholesterol and cholic acid showed higher plasma and liver total cholesterol and bile acid levels than those fed on the negative control diet. The difference of the plasma cholesterol level was due to the different LDL-cholesterol level. The plasma HDL-cholesterol level was rather reduced by the addition of cholesterol and cholic acid to the diet. Addition of GJP from adley or alfalfa to the high lipid diet was effective in reducing plasma LDL-cholesterol and phospholipid levels and plasma, lever and fecal bile acid levels of rats. Fecal cholesterol increased by feeding alfalfa GJP. Italian ryegrass GJP had no effects on any values determined in the present experiment. The effectiveness of the adley GJP was not due to hexane, ethanol and water insoluble portion of it. Addition of heat-coagulated portion of adley green juice to the diet as to offer the same nitrogen as GJP was not effective but addition of it at the level of 20% of the diet was effective in improving the plasma and liver lipid levels, suggesting the efficacy depends on some substances other than protein. The effectiveness of the addition of GJP to a diet containing low fat and no cholesterol was not found in such a short term experiment of 2 weeks except for a significant increase of liver phospholipid level.

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Adley (Coix lacryma-jobi L.) foliage was harvested three times a year at the stage of ear emergence and was used for the preparation of wilted silage and pressed cake silage. Pressed cake was prepared by crushing, pressing and dejuicing the foliage. In every harvest, pressed cake silage was low in crude protein, ether extract and crude ash contents and high in crude fiber and nitrogen free extract content compared with wilted silage. Both the silted and the pressed cake silages from the third harvest were good in chemical quality, while wilted silages from the first and the second harvests were in poor quality. But the poor quality was improved by processing the materials to pressed cake at the time of ensiling. The silages from the three harvests were fed to goats with the same amount of dry matter from wheat bran in two 4×4 Latin square trials. In every harvest, DCP content of wilted silage was a little higher than that of pressed cake silage, though the differences were very small. Between the three harvests, the first one was superior to the second and the third harvests in the digestibility of crude fiber. But no systematic and significant differences were found in TDN. As the results, DCP and TDN contents of every mixed ration were similar and were about 10 and 70%, respectively, in dry matter basis. No any abnormalities were found in the ruminal VFA and ammonia concentrations. Plasma cholesterol conceotrations of goats were not affected by the dietary treatments.

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In order to utilize stipe of mushroom (Agaricus bisporus SING.) for animal feed, stipe was dried (freeze, 80℃, 120℃) and ground to make powdered feed. Edible part of mushroom was freeze-dried as a control. 1. The contents of crude protein, crude fat, NDF and mineral (% of dry matter) in stipe showed 25%, 1%, 45% and 18%. Crude protein and crude fat contents in stipe were half as much as those in edible part. On the other hand, the contents of potassium (K), calcium (Ca), magnesium (Mg), phosphorus (P) and sodium (Na) in stipe showed 3.3%, 0.3%, 0.2%, 0.8% and 0.14%, respectively. Those value except for P in stipe were higher than those in edible part. Especially, Ca content showed 15th times higher than that in edible part. 2. Amino acid contents (% of dry matter) in stipe showed lower value of 15% as compared to 25% in edible part. Leu, Arg, Glu, Tyr, and Asp formed 55% of total amino acids in stipe. On the other hand, Cys was not detected and Met content showed the lowest value under 0.3% 3. Pepsin-pancreatin digestibility and percentage of soluble nitrogen in total nitrogen in stipe showed about 50% and 30%, respectively. 4. Using stipe as silage-additives, fermentation quality of silage was good even though adding 5% of fresh material. 5. Drying stipe at 120℃ seemed to be the most effective treatment in shortening of drying hours and palatability of dairy cattle.

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The Nezasa type grassland is spread over infertile soils of Aso mountain area, and Nezasa grows well in deciduous broad-leaved forests in Kyushu, south western Japan. To understand the growth characteristics of Nezasa growing in such poor environment, seasonal changes in the amounts of standing crop, nitrogen, and potosynthetic rates of Nezasa were measured. 1. Nezasa growing in forests Nezasa growing in forests from May to June had a high photosynthetic rate under low light intensity (0.68 mgCO_2・s^<-1>・m^<-2> under the condition of 600 μmol・s^<-1>・m^<-2>) and transferred the large amount of photosynthate into a small number of culms. The rapid elongation speed of the culm (1.3 cm/day) in spring is considered to be a consequence of this. These growth characteristics of Nezasa seem to be an important factors in the development of Nezasa-dominamt communities in forests. 2. Nezasa type grassland in infertile soil even though the amount of nitrogn absorbed from soil was small (0.84-1.03 mgN・m^<-2> from April to August), a lot of nitrogen was stored in underground plant parts at the start of the growing season (8.18-9.27 mgN・m^<-2>). Nezasa then transferred stored nitrogen to aboveground plant parts in the first half of the growing season (1.60-1.68 mgN・m^<-2>). In autumn, the nitsogen in the aboveground plant parts was again translocated to underground plant parts. This characteristic of Nezasa is an important element to preserving Nezasa type grasslands in the infertile soil of the Aso mountain area.

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The present investigation was conducted to elucidate the influences of planting density on the nutrient values and the fibrous components in different types of sorghum cultivars. Three cultivars, namely SCS 405 as sorgo type, SG-1 A as sorgo type with high sugar and Suzuho as dual purpose type (Utilization of whole plant including grain, leaf and stem), were grown in the field at three planting densities of 476, 1,481 and 4,668 individuals are^<-1>. The results were summarized as follows. 1. Increased planting density tended to bring about the promotion of maturation and the increment of yields in all the cultivars tested. 2. Planting density had a significant influence on fiborus components in the whole-crop silage of the cultivars tested. The fibrous components including crude fiber, neutral detergent fiber, organic cell wall (OCW), and cellulase low digestible cell wall fraction (Ob), increased with higher planting density, while nitrogen free extract contents decreased. 3. There was the varietal difference on the influences of planting density on the proportion of leaf and blade, rind, pith and ear to the whole plant in dry matter basis. With the increasing of planting density, the proportion of the rind of the cultivars SCS 405 and Suzuho increased and the proportion of ear of Suzuho significantly decreased. However, there was little change of the proportion of plant portion of SG-1 A in any planting density. 4. The contents of OCW and Ob varied with plant portion and cultivars, but not planting density. Quantities of both OCW and Ob were the highest in the rind of stem, whereas OCW and Ob in SG-1 A showed low contents compared to those of the other cultivars.

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Single basal application of nitrogen fertilizer using polyolefin coated urea (POCU) on dent corn (Zea Mays L) cultivation was conducted in strongly acid Andisol in 1987-1988. Controlled release nitrogen, POCU (LP 70 or 100 of Chisso-Asahi Fertilizer Co.), was used in dent corn cultivation to save the labpr of topdressing and to maintain the nitrogen nutrition of dent corn in late growing stage. 1) Dry weight and amounts of nitrogen uptake by dent corn at critical level (about 1 m of plant height) were only 1/30 and 1/10 of that at harvesting, respectively. At that critical level, mechanical topdressing was difficult. 2) According to the climatic data of last 21 years, the rainfall more than 1 mm/day which makes difficulties in machine work, appeared every two days around the time of mechanical topdressing. 3) Basal band application of more than 12.5 kg N/10a of amnoniun sulfate inhibited the growth of dent corn significantly, but not that of POCU at least by 40 kg N/10a. 4) Dent corn grown on the plot of single basal application of POCU showed equal or more amounts of nitrogen uptake and yield, and higher lodging resistance to that grown on the conventional plot with topdressing. 5) Amounts of nitrogen released from POCU highly correlated to both cummulative soil temperature and air temperature. 6) Single basal application of POCU are practically useful method for not only labor saving and maintaining the growth of dent corn in late growing stage, but also lowering the impaction of nitrogen fertilyzer to global circumstance.

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The experiment was conducted to evaluate the effect of cutting interval on quality and palatability of napiergrass (Pennisetum purpureum SHUMACH) Silage. The grasses were harvested on 6, 8, 10 and 12 weeks interval from February to November and were ensiled in laboratory silos. Fibrous compounds increased, while dry matter digestibility and crude nitrogen content decreased with increasing cutting interval. Total non-structural carbohydrate (TNC), which ranged between 5% and 8% on dry matter basis, increased a little as increasind cutting interval. The fermentative quality of each silage was relatively high, because lactic acid content of napiergrass silage at different cutting times was over 6% on dry matter basis and contents of the other organic acids were very little. The average value of pH of silage was lower than 4.2 in respective cutting intervals. But the fermentative quality of silage on the last Cuts of various intervals either during autumn or winter season, however, was slightly low. It is suggested that this tendency depended on TNC content of less than under 6.0%. the low palatability by cattle was clearly noticed in 12 weeks interval silage. This is considered to be caused by low dry matter digestibility. It is suggested that napiergrass may be cut and ensiled at between 8 to 10 weeks interval of growh.

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Three experiments were conducted to examine the fermentation process and the effect of some pre-ensiling treatments on quality and palatability of napiergrass (Pennisetum purpureum SHUMACH). The grasses were harvested four times per year at ten weeks interval and were ensiled in laboratory silos after the following treatments : (1) Sample with no treatment (control), (2) Wilting for 2 to 3 hours (wilting) and (3) Addition of molasses at the rate of 3-9% as silage additive (molasses) in both experiment 1 and 2. In experiment 3, the grasses were harvested four times per year at eight weeks interval and were ensiled in laboratory silos after the following treatments : (1) Sample with no treatment (control), (2) Wilting for 2 to 3 hours (wilting), (3) Inclusion of beat pulp at up to 5% (beet pulp), (4) Inclusion of bagasse at up to 5% (bagasse) and (5) Inclusion of citrus pulp at up to 5% (citrus pulp) as an additive to control water and available carbohydrate content. The fermentative quality of treated silage was either same or higher as compared with the control. The ratio of lactic acid content to total organic acids of the respective silage was increased by these pre-ensiling treatment. The lactic acid content especially was increased to over 10% on average and pH also decreased to under 4.0 in both molasses and citrus pulp treated pulp silages. The fermentative quality of grass harvested and ensiled either autumn or winter season, where the available carbohydrate content was less than 6.0%, was lower than in the other harvest times in all treatments. There were no positive correlation between fermentation quality and palatability by cattle. High palatability was however observed with beet pulp treated silage which have high dry matter digestibility and with wilted treated silage which controlled water content. On the contrary low palatability was observed with molasses and citrus pulp treated silage both of which indicated low pH < 4.0, and with bagasse which had low dry matter digestibility.

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Extraction and detection methods of 4-methylimidazole (4-MI) of ammoniated-roughage have been studied. Recovery of 4-MI from ammoniated-roughage was higher in ion-pair extraction method compared with sodium carbonate-chloroform-ethanol extraction method and hydrochloric acid-chloroform-ethanol extraction method. there was no difference among the ion-pair high performance liquid chromatography (HPLC) method, dansylated sample-HPLC method and acetylated sample-gaschromatography-mass spectrometry (GC-MS) method on 4-MI values determined.

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A large-sized weed grown on dent corn field was found both in experimentel farms of Tohoku University (Miyagi Pref.) and Iwate Agricultural College (Iwate Pref.) and was identified to be Nicandra physalodes (L.) Pers. by their morphological characteristics. Nicandra physalodes (L.) Pers. reached more than 3 m in plant height and completely smothered dent corn at the time of harvesting. Consequently, dent corn grown on this field showed drastic reduction in dry matter yield, especially in grain yield. Foliar treatment of herbicide at fourth leaf stage of the weed, Bentazon (500 g/10a), was most effective to control Nicandra physalodes (L.) Pers. without any damage to dent corn growth.

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Winter injury of orchardgrass plants had been continuously surveyed in grassland fields at 17 locations over 4 years in Tokachi district, Hokkaido. Winter injury was caused mainly by Sclerotinia borealis BUB. & VLEUG. Severe injury by this snow mold was observed only in the locations where plants were exposed to air temperatures below -15℃ before snow cover and thereafter kept under deep snow cover more than 50 days. Consequently, it was recognized that not only duration of snow cover but also the lowest air temperatures before snow cover were the important meteorological factors responsible for this winter injury. Hence it was attempted to estimated degrees of winter injury using the data of these meteorological factors. The estimated degrees of winter injury at 17 locations in Tokachi district were well comparable with those actually observed. The degrees of winter injury at 170 locations over Hokkaido and for 22 years in Tokachi district were also estimated. The estimated degrees of winter injury accounted well for their local and seasonal variations in empirically known winter injury. These results supported the hypothesis that the low temperature stress before snow cover predisposed orchardgrass plant to severe injury by S. borealis.

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The efficiency of minerals for ruminants differs according to the kind of minerals and forage species. A possible factor causing this difference is the association between the efficiency of minerals and the digestibility of tissues where the minerals exist. The purpose of this experiment is to investigate the distribution of macrominerals in different tissues of tall fescue. A leaf blade of tall fescue cultivar 'Hokuryo' was taken from a flag leaf on June 30, 1992. Nine units - from 3 parts of 3 leaf sections - were investigated. Relative percentages of 7 mineral elements were determined quantitatively in 6 different tissues per unit using energy-dispersive X-ray analysis. In each unit, silicon and potassium (K) were the most predominant elements, followed by chlorine (Cl), calcium (Ca), sulfur and phosphorus ; a small amount of magnesium was also detected. Silicon existed mostly in epidermal structures. Although the other minerals were distributed generally throughout the sectional area, Ca was abundant at the developed secondary cell walls, and K and Cl were especially higher in vascular tissues. The low efficiency of ca is partially caused by the distributional pattern, and was abundant at developed secondary cell walls. However, no distributional relationship was observed for the other minerals.

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Aneurolepidium chinense grassland which distributes from Northeastern China to Inner Mongolia and is classified as meadow steppe produced a large amount of high quality forages and has been valuable natural resources. However, it is said that the grassland has been alkalined and severely degraded, owing to the irrational use in the recent 20-30 years. In order to clarify the ecology of degraded grassland from conservational point of view, a survey was carried out in the northwestern part of Harbin. The following results were obtained. 1. The coverage percentage of the bare ground in lightly degraded pastures was 27-33%, whereas that of heavily degraded was 47-78%. 2. Annual plants such as Chloris virgata and alkali-tolerant plants such as Iris loctea invaded into degraded grazing pastures indicating disturbance by heavy grazing. However, neither annual plants nor the bare ground was found in cutting pastures. 3. Soil pH was 8.47-8.90 in grazing pastures, whereas it was 6.17-6.46 in cutting pastures. Similarly, the soil electric conductivity and the soil hardness were higher in grazing pastures than those in cutting pastures. This fact indicates that physical and chemical properties of soil are severely devastated in grazing pastures. 4. The bare ground and three vegetation types were distributed in corresponding with the microtopography. These occurred in sequence from lower to higher land level as follows ; the bare ground, the Chloris virgata type, the Puccinellia tenuifolia type and the Aneurolepidium chinense type. The soil pH of the bare ground was 10.30 and that of the vegetation types described above were 9.08, 8.90 and 8.53, respectively. This fact indicates that different vegetation types develop in accordance with the soil alkalinity, and that no plant is able to survive in the highest alkali spot. It is considered that the soil alkalinity induce the bare ground and accelerates ecological degradation of grassland.

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Reactions of alfalfa protoplasts of sic genotypes (three resistant ant three susceptible genotypes) to Verticillium albo-atrum culture filtrates fractionized by different molecular cut-off (3,500, 12-14,000 and 50,000) and to the cell wall components were investigated. Protoplasts derived from susceptible genotypes reacted to a low molecular weight fraction (3,500 <) more highly than those derived from resistant genotypes. On the other hand, protoplasts derived from resistant genotypes reacted to high molecular weight fractions 12-14,000 〜 50,000, > 50,000) and V. albo-atrum cell wall components more highly than those from susceptible genotypes. These results indicate that low molecular weight fractions may be useful for in vitro selection using V. albo-atrum culture filtrate, and that the percentage of reacted protoplasts to the fungal cell wall components may be a good indicator for the in vitro resistance.

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