The present experiment was conducted to ascertain the differences in Total Nonstructural Carbohydrate concentration (TNC%) in stem beetween high and low snow endurance varieties in diploid and tetraploid Italian ryegrass in vegetative phase grown under low air temperature in fall. In order to make use of some properties as the indices of the nonstructual carbohydrate concentration, the relations of TNC% to some morphological and physiological traits were also investigated. High snow erdurance varieties showed significantly higher TNC% of dry and fresh matter than low snow endurance varieties both in diploid and tetraploid Italian ryegrass. It is considered that the nonstructural carbohydrate play an important role in snow endurance as the source of energy for the plants surviving under snow. The significant positive correlations between TNC% and dry matter percentage, and significant negative correlations between TNC% and Total Nitrogen percentage (TN%) were observed, indicating the possibilities of these properties to be used as the indices of nonstructural carbohydrate concentration. At the same time, it was also confirmed that tetraploid variety showed significantly higher intercept in the linear regression of dry matter percentage on TNC% than diploid variety. This result indicates that in case of using the dry matter percentage as the index of the nonstructural carbohydrate concentration, diploid and tetraploid varieties must be dealt with separately. In the linear regression of TN% on TNC%, no significant differences were observed both on the slope and intercept between diploid and tetraploid varieties. Correlation coefficient of specific leaf weight to TNC% was significantly high in diploid varieties, but not in tetraploid.

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The present experiment was conducted to acertain the differences in the concentrations and the characteristics of nonstructural carbohydrate in diploid varieties of Italian ryegrass at vegetative phase grown in fall. Seventeen diploid varieties of various maturities were used. Nonstructual carbohydrates of plant materials (leaf blade and stem) sampled every 7th days from 30 (Oct.25) to 65 days (Nov.29) after emergence of seedlings were extracted with ethanol solutions varying in concentration, i.e. 85%, 75%, 65%, 55%, and 0% (water) and determined by Anthron method. 1) Distinct varietal differences of nonstructual carbohydrate concentrations from 35% to 47% of the dry matter in stem were observed at the end of the experiment (65 days after emergence). 2) Differences of nonstructural carbohydrate concentrations in stem among varieties were primarily due to the differences in fructosan concentrations, and it is considered that such clear varietal differences as observed in fructosan do not exist in mono- and oligosaccharide concentrations. 3) It is recognized that the higher the concentration of fructosan in the varieties, the higher the degree of polymerization of fructosan is. 4) Relative differences in the concentrations and the characteristics of nonstructural carbohydrate between varieties showed the same trend in stem and leaf and at each harvest time, but the differences were clearer at the later part of the experiment. 5) In general, extremely early and early maturing varieties showed lower nonstructural carbohydrate concentrations, fructosan concentrations, degrees of polymerization of fructosan i.e. lower abilities to reserve carbohydrate than medium and late ones, but some exceptional varieties were also observed. 6) Significant positive correlation coeffecients between nonstructural carbohydrate concentration and specific leaf weight, and between nonstructural carbohydrate concentration and shoot weight were observed at the later part of the experiment and the relationships are discussed from physiological and morphological points of view.

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Two early cultivars of Italian ryegrass, Lolium multiflorum cv. Waseyutaka and Yamakei-No.12 (abbreviated to -1 and -12, respectively), were undersown into each of preceding crops, setaria (Setaria anceps cv. Kazungula, abbr. to S) or green panic (Panicum maximum var. trichoglume cv. Petrie, abbr. to P). These sowings were practiced immediately after cutting at 10cm above the ground level on each of three cutting- and sowing-dates, i.e. Sep.28, Oct.18, and Nov.11, as shown in Table 1-A. In relation to the different light and temperature environments resulted from the regrowth of these preceding warm-season grasses, suitable time for undersowing Italian ryegrass were investigated. Treatments consisted of three combinations of preceding crops with the cultivars of undersown Italian ryegrass (S-1, P-1, S-12) and each of Italian ryegrass cultivars as the Control (1-C and 12-C), which was after the entire removal of the preceding crop at each sowing time, as shown in Table 1-B. Results obtained are as follows: 1. Reduced establishment and delayed early growth of undersown Italian ryegrass were observed under lower light intensities with higher growth temperatures, especially in P-1 of Sep.-sown (Fig.1, 3 and Table 2). A great number of high position tillers from setaria stubbles was seemed to be more harmful to the establishment and early growth of undersown Italian ryegrass than the case of green panic (Tables 2 and 3). The difference was attributable to the light distribution pattern under canopy specific to each species (Fig.2). 2. undersown Italian ryegrass recovered rapidly its delayed early growth after Nov.11, when the final cutting of the preceding crops was applied, especially in S-1 of Sep.-sown, where Italian ryegrass had grown under heavily shaded environment (Table 3). 3. Total dry matter yield of undersown Italian ryegrass together with the regrowth of each preceding crop showed no significant difference from that of the Control, Italian ryegrass pure sward sown on the same day (Fig.4). But when the undersowing was practiced 20 days earlier than the Control, more increased dry matter was produced continually during autumn (Table 4). 4. These results show that suitable time in northern Kyushu for undersowing Italian ryegrass into these preceding warm-season grasses is in late September, and allowable in mid October in case of preceding green panic. But the important practices to secure better establishment and early growth of undersown Italian ryegrass are to raise sowing rate of it and clear the preceding canopy within 20 days after sowing to maintain relative light intensity above 20% at the ground level.

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Orchardgrass sward of the 2nd harvest year managed in low fertilization level received 3 levels of fertilization after the 1st cut or the 2nd cut, respectively. The levels were high: 80kg N+40kg P_2O_5 +70kg K_2O/ha, Medium: 40kg N+20kg P_2O_5+35kg K_2O/ha, and low: 20kg N+10kg P_2O_5+17.5kg K_2O/ha. Clipped part (cut at 6cm), stubble and root of swards were harvested at weekly intervals up to 8 weeks for each regrowth, and leaf and stem were divided into living and dead matter. The dry weight, plant height, number of tillers, LAI, percentage light penetration and TNC in stubble were measured at weekly intervals. Changes of measured values in yield and growth with time were well fitted by the cubic regression curves. In the early stage of regrowth, yield, LAI, plant height and number of tillers increased more rapid with the increment of fertilizer, and percentage light penetration was decreased to 5% in about 3 weeks for high, in about5 weeks for medium, and in about 8 weeks for low level of fertilization. Living yield changed to decline in about 6weeks for high level of fertilization, as dead matter of clipped part began to increase in about 5 weeks and the increase was accelerated with the increment of fertilizer. Percentage TNC in stubble was decreased and the recovery was retarded with the increment of fertilizer. Maximum stages of average productivity (suitable cutting stages in theory) for regrowth after the 1st cut and the 2nd cat were 4.4 and 4.5 weeks for high, 4.5 and 4.8 weeks for medium, and 3.5 and 3.9 weeks for low level of fertilization, and the average productivity (yield of living matter/regrowth duration) were 9.0 and 7.8g/m^2/ day for high, 6.4 and 5.3g/m^2/day for medium, and 4.6 and 3.8g/m^2/day for low level of fertilization, respectively. For high level of fertilization, plant height, LAI and percentage light penetration at maximum stages of average productivity were similar to the corresponding values in previous paper (plant height 74cm, LAI 7.4, light penetration 1%), but for medium and low levels of fertilization, the values were not conform to them. The results described above suggest that cutting in the suitable stage of orchardgrass sward is essential to obtain the high yield of living matter, especially for the high level of fertilization.

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Using cubic regression equations obtained in previous paper, growth analysis was carried out to elucidate the effects of fertilization level on regrowth of orchardgrass and the effects of plant part used for the analysis on the results. With increment of fertilizer, leaf area was developed rapidly and optimum LAI, maximum LAI, maximum CGR, and LAD were increased. As living matter in whole plant was used for the analysis, optimum LAI in 2nd (23 May to 18 July) and 3rd (4 July to 29 August) crops were 4.4 and 4.2 for low, 5.3 and 5.1 for medium, 7.6 and 6.5 for high level of fertilization, and maximum CGR in 2nd and 3rd crops were 8.9 and 6.0g/m^2/day for low, 10.3 and 9.0g/m^2/day for medium, 12.9 and 12.2g/m^2/day for high level of fertilization, respectively. Both of optimum LAI and maximum CGR were apt to increase as dead matter was included for the analysis, and apt to decrease as clipped part or top was used for the analysis. The differences of them were small between with and without dead matter or between top and whole plant, but not negligible between clipped part and whole plant. Negative values of NAR and CGR were observed during the stage from 0 to about 1 of LAI in top, and from 0 to about 2 of LAI in whole plant, with all fertilization levels. NAR in whole plant were attained to the maximum at the stage about 4 to 5 of LAI and declined to the negative values again at the stage about 5 of LAI for low, about 7 of LAI for medium, and about 9 of LAI for high level of fertilization, respectively. But changes of NAR with time were similar levels in whole plant with all fertilization levels. LAR were increased with increment of LAI, and SLA were decreased with progress of regrowth, and similar values of them were observed with all fertilization levels. The results decribed above suggest that high dry matter production with increment of fertilizer resulted from rapid increase of LAI and lenient decrease of NAR to LAI, and samplings of living matter in clipped part and stubble are indispensable for growth analysis in 2nd and 3rd crops of orchardgrass sward.

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In order to identify subtropical grass species and varieties which would be productive, frost-tolerant and would grow vigorously under relatively low temperature conditions, twenty-two subtropical grasses were compared for their growth characteristics, seasonal production and winter hardiness. Field experiments were conducted at two contrasting sites. One relatively cold site was at Canberra, A.C.T. (Ginninderra) and site with relatively mild winter temperatures was at Berry, N.S.W. The species and varieties tested comprised 10 varieties of Chloris gayana, 5 Setaria sphacelata, 2 Cenchrus ciliaris, and one each of the following, Paspalum dilatatum, Panicum maximum var. trichoglume, P. coloratum, Sorghum almum and Digitaria argyrograpta. The more productive grasses were varieties of Chloris gayana, Sorghum almum and "Kazungula" Setaria sphacelata (N.810). The only grasses able to survive a cold winter were Paspalum dilatatum and Digitaria argyrograpta. Those tolerating mild winter temperatures in addition to those two specise were "Nzoia" and "Pioneer" Chloris gayana, Sorghum almum, Panicum coloratum and all five lines of Setaria sphacelata. It is suggested that further exploration of highland tropical regions could provide lines of Chloris gayana and Setaria sphacelata capable of high summer production in the warm temperate areas of Japan.

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Five Rhodesgrass varieties from different altitudes in East-Africa were compared to evaluate their growth response to a range of temperatures. The plants were grown for three weeks in the Phytotron at Canberra at the following day/night temperatures: 15/10, 18/13, 21/16, 27/22 and 36/31℃. 1. Over the temperature range 15/10 to 36/31℃, dry matter production and tiller number per plant increased with a rise in temperature in all Rhodesgrass varieties. Stolon number also increased with temperature up to 27/22℃ but declined sharply at 36/31℃. Leaf number for most cultivars followed a trend similar to stolon number, but the decline in numbers at 36/31℃ was less marked for leaves than for stolons. 2. At the lowest temperature of 15/10℃ all varieties showed stunted growth and yellowing of the leaves. However, the varieties from areas of higher altitude, Nzoia and Massaba, together with Pioneer displayed more vigorous growth, a higher net assimilation rate and a greater number of leaves than the varieties from low altitudes, Serere and Mpwapwa. 3. The present studies provide some evidence that temperature responses of varieties are related to climatic conditions of their native habitats.

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Polysacchrides-exudates from crop roots accompanied with the growth of root-system were investigated. Five crops, Italian ryegrass, upland rice, wheat, barley and alfalfa were used in this experiment. The experimental period at the water culture of Italian ryegrass and upland rice were 11 weeks and the other crops were 5 weeks, respectively. The polysaccharides in culture solution were collected and measured for glucose fraction with anthrone and uronic acid fraction with carbazole-sulphate. The results are summarized as follows ; 1) According to the investigation of root-system distribution at the 5 weeks growth stage, the wheat and barly showed complex distribution compared with Italian ryegrass and upland rice. In the former species, there were more numbers of the lateral roots which developed from adventitious roots and longer root length as a total. 2) Amount of exudated glucose was 4-5mg in wheat and barley, 1.8mg in upland rice, 1.0mg in Italian ryegrass and 0.7mg/10 plants day in alfalfa, respectively. It is considered that the amount of exudated glucose depends on the different numbers of root per plant. 3) According to the investigation on the variation of glucose exudates with advanced growth of Italian ryegrass and upland rice roots, the maximum value of glucose content of both plants were obtained at the 5 weeks growth stage, and the maximum value was about 2mg/10g fresh root weight. 4) The maximum value of Relative Growth Rate (RGR) showed at the 3-5 weeks growth stage. 5) From these experimental results, it was concluded that the polysaccharide-exudates of roots increased in quantity when the growth were active.

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In the present paper, we deal with the influence of three culture medium, water culture, glass beads culture and sand culture on polysaccharide-exudates from Italian ryegrass and alfalfa roots. The results are summarized as follows ; 1) Root-system in water culture was distributed straight and that in particle cultures such as glassbeads and sand were increased in root number and individual root became fine and crooked. 2) On both forages, there were lots of polysacchride-exudates in particle culture. In case of glucose, for example, exudates in particle culture were approximately six to seven times as much as exudates in water culture. 3) It is considered that the roots which touched with particles are subject to physical impetus and, as a consequence, polysaccharide-exudates in particle culture seemed to increase.

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Successive enzyme treatments with amylase, pronase and cellulase were applied to forages and silages such as corn silages, orchardgrass hays, rice straw, mixed hays mainly of orchardgrass, alfalfa hays and artificially dried samples of alfalfa and orchardgrass. Organic matter was divided into two fractions, organic cellular contents (OCC) and organic cell wall (OCW), by amylase and pronase digestions. Next, OCW was divided into two fractions, organic a (Oa) and organic b (Ob), by cellulase digestion. Digestibilities of OCC were much higher than those of OCW except rice straw, and digestibilities of Oa were far higher than those of Ob in all hays and silages. It is observed that mean digestibility of Ob of alfalfa hays was considerably lower than those of grass hays, corn silages and rice straw. While, lignin contents in Ob of alfalfa hays (23.3M±1.1%) were always higher than those of grass hays (12.2±0.9%). Highly significant correlations (P<0.01) were obtained between total "OCC plus Oa" and digestible "OCC plus Oa" in all feed groups. Significant correlation (P<0.05) was recognized between OCW contents and digestible OCW in corn silages, but there was no significant correlation between them in the case of alfalfa hays and grass hays group (orchard-grass hays, mixed hays mainly of orchardgrass and rice straw). There were highly significant correlations (P<0.01) between the amounts of whole Oa and digestible Oa in all feed groups. Similar correlations were found between whole Ob and digestible Ob in corn silages and grass hays group. With advancing stage of maturity, OCC decreased and OCW and lignin increased gradually in both of alfalfa and orchardgrass. The level of Oa in OCW decreased and that Ob increased during growth in both species.

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The purpose of this study was to examine the effects of difference in nitrate contents in grasses and levels of glucose addition on the disappearance of nitrate in forage crops during ensilage. 1. More nitrate seemed to have disappeared during the ensilage in grasses containing more nitrate. Nitrate disappeared to a large extent in poor quality silage. 2. Glucose addition was definitely effective for obtaining excellent quality. But glucose addition depressed disappearance of nitrate. Once good quality was obtained by a certain level of glucose addition, further increase in added glucose did not change the rate of nitrate disappearance. 3. Correlation coefficients between Flieg's evaluation, pH value and NH_3-N/Total-N with disappearance of nitrate were -0.686, 0.666, and 0.586, respectively.

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This experiment was undertaken to investigate the efiects of moisture content and degree of consolidation of material on the chemical quality and aerobic deterioration of fresh rice straw silage. The fresh rice straws harvested with a combine harvester were ensiled at three moisture levels (high, medium and low) adjusted by pre-wilting, in a cubic-type can silo, equipped with an inner polyethylene foil bag, wood cover and metal stopper for keeping a constant volume after filling the material using a pressing machine. The following six kinds of treatments were applied, (1) high moisture and heavy consolidation, (2) high moisture and light consolidation, (3) medium moisture and heavy consolidation, (4) medium moisture and light consolidation, (5) low moisture and heavy consolidation, and (6) low moisture and light consolidation. The high, medium and low moisture contents of raw rice straws were about 72, 67 and 62%, and the degrees of heavy and light consolidations were 500kg/m^3 and 400kg/m^3, respectively. The silos were kept anaerobically during six months at ambient temperature. After opening silos the chemical analyses were carried out with silages, and the temperature changes during the aerobic period were measured using thermister with six channels. The results obtained were as follows: 1) The pH values of the silages heavily consolidated in three moisture levels were higher than those of the light consolidated silages, but the lactic acid contents of the former were generally lower than those of the latter. 2) Acetic acid contents in the low moisture silages were higher than those of high and medium moisture silages, but the contents of butyric acid and other higher VFA were remarkably low in the low moisture silages. 3) Both temperatures of high and medium moisture silages tended to rise more notably than those of low moisture silages at nine days after opening silos. Moreover, the light consolidation had an effect to increase the maximum temperatures of high and medium moisture silages.

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The relationship between the moisture content of raw material and the distribution of volatile components in silage, and changes in composition of volatiles after opening silos were studied. Cocksfoot was ensiled in three states; high moisture silage, immediately ensiled; medium moisture silage, pre-wilted for about 24h; low moisture silage, pre-wilted for about 36h; and then preserved for 70 days under anaerobic conditions in the bags of polyethylen film. The pH values of both high and medium moisture silages were higher than that of low moisture silage, but the lactic acid contents of the former were lower than that of the latter at opening and during aerobic deterioration. A number of volatiles were found in the silage distillates, and the total yield of volatile components at opening silos was much higher, in high moisture silage than in both medium and low moisture silages. Among the volatiles ; iso-pentanol, cis-3-hexenal, β-phenylethanol, 4-ethylguaiacol, 4-ethylphenol in the high moisture silage ; iso-pentanol, β-phenylethanol, 4-ethylguaiacol, 4-ethylphenol, ethyl linolenate in the medium moisture silage ; and iso-petanol, , β-phenylethanol, ethyl linolenate in the low moisture silage were relatively large in peak area distribution at opening, respectively. The patterns of the peak area distribution of the volatile components in silages were altered by both the moisture contents of silages and the time intervals under aerobic condition.

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Fresh ladino clover was ground with the addition of water and devided into a liquid and a fibrous fractions through double gauze. The fibrous residues containing about 85% of moisture and less than 4% of water soluble carbohydrates on dry matter basis were ensiled into bottles of 0.8l capacity with or without additives such as glucose, leaf protein concentrates, or sodium citrate. For comparison, chopped or ground original herbages were also ensiled in the same scale silos. The silages from the fibrous residues with orr without additional glucose or leaf protein concentrates were always better in quality than those from the unextracted clover. Various amounts of sodium citrate were added to the fibrous residues at the time of ensiling and even in the case of the smallest addition, which was a quarter or third of the amount needed to bring the buffering capacity of the fibrous residues to that of the original clover, the increase of pH of the residue silages was observed. According to the increase of the rate of sodium citrate to the residues, the pH value of the silages increased. These results show that buffers are more influential on silage quality than sugars, proteins, and physical conditions and that the difference in silage quality between the fibrous residues and their original clovers are largely attributed to the different buffering capacities.

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