The pattern of degradability by bacterial α-amylase (Bacillus subtilis) was described to analyze the varietal differences in ruminal digestibility of ground corn. We discussed the relationships among the pattern, 12 hr dry matter disappearance by in situ bag technique and chemical composition. The materials were 19 maize genotypes contained 7 kernel texture, such as dent, flint, waxy, sweet, pop, high amylose and high oil. The ground kernel (0.5 mm, 1 g) were incubated at 40℃ with continuous shaking in 40 ml of enzyme solution (phosphate buffer, pH 5.8) containing 1 mg α-amylase. The pattern of degradability was described by using the ORSKOV and McDONALD's equation of the form : Yt=a+b(1-e^<-ct>), where a, b and c are constants fitted by an iterative least-squares. Yt means the percentage of disappearance at incubation time t. The parameter a represented a very rapidly degradable fraction, while b was less rapidly degradable fraction disappearing at the constant rate c, per unit time t. The varietal differences to α-amylase digestion clearly appeared among different kernel textures. The mean of parameter a was 50.1% for sweet corn and higher than the other textures which were distributed from 10.7 to 15.4%. The means of b were about 38% for waxy and high oil corn, about 20% for sweet and pop corn, and intermediate for the other textures, respectively. The c were calculated about 0.9 for sweet corn, 0.4 for flint, dent and pop corn, and 0.2 for waxy, high amylose and high oil corn, respectively. Moreover, the sum (a+b), as indicating 'the potential degradable fraction', could be separated into three groups, such as sweet (about 70%), waxy and high oil (about 50%) and dent, flint, pop and high amylose (about 40%). In situ 12 hr dry matter disappearances were higher about 10% than the sum values (a+b) on the averages, and significantly correlated to a, c and a+b. The corrected dry matter disappearances (CDMD), which were calculated by the percentage of 12 hr dry matter disappearance minus water soluble fraction content at zero incubation time, were higher about 10% than b, and correlated significantly. There were not significant correlations between b and the contents of chemical constituents such as starch and nitrogen ・ cell wall free extracts. The results suggest that these varietal differences of digestibility in the rumen without early period of incubation are mainly due to susceptibility of starch to α-amylase.

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Twelve mixtures of chopped rice straw -1) Co : rice straw (RS) alone; 2) CoM:RS+molasses; 3) So:RS+sodium hydroxide (2% DM) (NaOH); 4) SoM:RS+NaOH+molasses (10% DM); 5) Su:RS+soybean meal (5% DM) (SM)+urea (5% DM); 6) SuM:RS+SM+urea+molasses; 7) Ma:RS+cage layer manure (30% DM) (CLM); 8) MaM:RS+CLM+molasses; 9) SoMa:RS+NaOH+CLM; 10) SoNaM:RS+NaOH+CLM+molasses; 11) SuMa:RS+SM+urea+CLM; and 12) SuMaM:RS+SM+urea+CLM+molasses-were packed in 4-kg double-layered polyethylene bags and allowed to ferment. Samples were taken before processing and 45 and 90 days after processing and subjected to analysis. Physical characteristics, chemical composition, digestibility and fermentation characteristics of 45-day and 90-day mixtures were generally similar. Molds were observed in the upper surface layer of all mixtures except in Su, SuM, SuMa and SuMaM. Crude protein (CP) contents of Su, SuM, Ma, MaM, SuMa and SuMaM were higher than other mixtures (p<0.01). All treated mixtures had consistently higher digestible organic matter in dry matter (DOMD) than Co (p<0.01). Ammonia nitrogen percentage (NH_3-N/Tot-N) was higher than 8% in Su, SuM, Ma, MaM, SuMa,and SuMaM. Lactic acid was not observed in mixtures treated with CLM. This could be due to a combination of low fermentable carbohydrates, low sugar to protein ratio and high buffering capacity due to a relatively high ash content of CLM. Mixtures with combination of soybean meal, urea, CLM and molasses showed the highest digestibility (DOMD %) at 45 and 90 days after processing.

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Interactions between alfalfa and Verticillium albo-atrum were examined in terms of the following aspects:growth of V. albo-atrum on callus;growth of callus on the medium containing culture filtrate of V. albo-atrum and production of antifungal substances in callus treated with cell wall components (elicitor) from V. albo-atrum. Mycelial growth of V. albo-atrum was likely to be suppressed on the callus from resistant cultivars (Vertus and 5444), accompanied by strong browning. The growth of callus from Vertus (resistant, R) and Kitawakaba (susceptible, S) were vigorous on the medium containing 0.5 or 1% culture filtrate, while those from 5444 (R) and Europe (S) were inhibited. Antifungal substances were detected in all cultivars treated with cell wall components, with concentrations being higher in resistant than in susceptible cultivars. These results suggest that antifungal activity in the callus extracts indicated by the inhibition of germ tube elongation of fungal conidia is the best criterion for the selection of resistant cultivars.

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In order to clarify the effects of soil and plant in purification of the animal waste water in the land application system, an experiment have been carried out with 1/2,000 a wagner pot. The wagner pots, in which barnyard millet (Echinochloa utilis OHWI et YABUNO) were grown, were set up in the same structure (Fig. 1) as the new animal waste water purification plant which have been constructed experimentally in Azabu University. For maintaining good aeration and drainage condition, pebbles, zeolite and clinker ash were filled on the under layer, and mixture of perlite and soil (andosol) was filled on the upper layer of pot. Four plots were set up for experiment, namely, the waste water-barnyard millet plot (WBM), the waste water-bare land plot (WBL), the public water-barnyard millet plot (PBM) and the public water-bare land plot (PBL). The waste water, which received the primary treatment of aeration and sedimentation was flooded into under layer of the pot. In WBM and WBL plot 250 ml of the waste water was flooded every day, for sake of contrast, in PBM and PBL plot public water was flooded. All the pots received public water amount of 1 l, equivalent to precipitation, every week. Growth of plant and water consumption were surveyed, and chemical constituents of plant, soil and water of the flooded and drained were analyzed. The results obtained were as follows : 1. Water balance (Table 3 and Fig. 3). Drained water decreased 58%, considerably in the barnyard millet plot by evapo-transpiration, but only 27% in the bare land plot, indicating that the plant was effective in water treatment. Seasonal trend of evapo-transpiration changed tremendously corresponding with plant growth, cutting treatment and climatic condition. However, evaporation did not change much seasonably. 2. Quality of drained water (Table 4). In the bare land plot removal ratio of COD, SS and T-N were 59-79%, however, these of BOD were only 25%. On the other hand, in the barnyard millet plot removal ratio of all of these pollutants were 88-97%. It was concluded that the plant was effective measure for removing BOD and that combination of soil and plant was successful for purification. 3. Comparison of purification efficiency of pot with that of the animal waste water treatment plant (Table 4). In the waste water treatment plant removal ratio of T-N was only 21%. In contrast, in the present experiment, these ratio was 90%, extremely higher than the waste water treatment plant. This fact suggested that purifying efficiency of the waste water treatment might be enhanced by improving the soil condition of land application system.

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The purpose of this study was to determine the effects of inoculation of lactic acid bacteria (LAB) on the recovery of dry matter, fermentative quality, distribution of isomers of lactic acid and nutritive value in silage. The silage materials were oats at heading stage with 81.1% moisture (M) and 9.1% water soluble carbohydrates (WSC), Italian ryegrass at heading stage with 82.3% M and 9.0% WSC, paddy rice at dough stage with 63.1% M and 11.1% WSC and corn at ripe stage with 67.0% M and 15.1% WSC contents on dry matter basis. These materials were ensiled in 300 l polyethylene vessels. Treatments used were Lactobacillus casei (Lc), L. casei+Streptococcus lactis (LS) and untreated (Ut). Treatment Lc and LS were inoculated with 1.0×15^5/g and with 7×10^4 of L. casei and 3×10^4 of S. lactis/g of silage material, respectively. The following results were obtained : 1. Recovery of dry matter increased in silages inoculated LAB compared to Ut. 2. Silages with inoculants of LAB obtained a rapid pH decline and more lactic acid content but silages without inoculants of LAB showed higher pH value and contained great amounts of acetic acid and higher ratio of volatile basic nitrogen to total nitrogen (VBN/T-N). Therefore, the fermentative quality of silage was largely improved by LAB inoculation. 3. In the distribution of lactic acid isomers in silages, inoculation of LAB decreased D(-) lactic acid content and increased L(+) lactic acid. 4. Crude protein (CP) and crude fat (EE) contents were higher in Lc and LS than in Ut. Digestibilities of CP and some EE and digestible nutrients followed the same tendency. Distinct significant increase of CP and EE digestibilities in paddy rice and corn silages were observed. As a result, both DCP and TDN contents were increased to a large extent. 5. The inoculation of LS did not have a greater effect than inoculation of Lc. Therefore, L. casei was found to play a more important role in silage fermentation. From the above results, inoculation of LAB gave beneficial effects by increasing L(+) lactic acid content and nutritive value as well as improvement of fermentative quality and recovery of dry matter in silages. Furthermore, inoculation with homofermentative LAB validates a more efficient fermentation and production of silages with higher lactic acid contents and ratio of L(+) lactic acid isomer.

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Twenty five populations and cultivars of tall fescue orignated in Central and South Europe, North Africa and West Asia, and three check cultivars were compared in the warm temperate zone of Japan for heading habit, seasonal growth, and crown rust resistance. Entries originated in Europe consisted of five early maturing populations and seven very late maturing populations which were derived from the mountainous area. Maturity of thirteen populations originated in North Africa and West Asia varied from early to medium, and their culm and spike lengths were generally longer than thnose of the populations originated in Europe (Table 1). The habit of seasonal growth was evaluated by principal component analysis on the basis of 15 characters related to seasonal growth. About 92% of the variation was extracted by the first, second and third components (Table 2). The first component shows the main growing season. The second component represents forage productivity. The third component appears to indicate the relation between summer and fall growth in the early stage and that in the grown stage. Entries were classified into two groups by the score of first component. Thirteen cultivars and populations originated in North Africa and West Asia belong to the Mediterranean Group, of which main growing season was late fall to spring. The entries belonging to Mediterranean Group were separated into the three subgroups, "M I", "M II" and "M III", by the scores of second and third components (Fig. 1, Table 4). Main growing season of the entries originated in Europe and checks was spring to fall, and they were separated into three subgroups by the scores of second and third components, too. Five early populations and two checks, "Yamanami" and "Fawn" consisted of "E I" group. They had good potentials for growth from early spring to fall in the warm region of Japan. Seven very late populations were formed "E II" group. In these characters, cultivar "Hokuryo" behaved intermediately between "E I" and "E II" group. Mediterranean group indicated high resistance to crown sust. "E I" group and "Hokuryo" had higher survival rates than the other group at the third years after transplanting.

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Horizontal diffusion pattern of plant is one of important parameters determining the trait of netting growth and production in turf grass. However, it is considerably diflicult to express accurately such a complicated pattern by some existed scales and indicators prepared for the analysis of population structure. Recently fractal dimension has come to be widely used as a scale to express the form of object. In this paper, we took up fractal dimension as a new scale to determine the diffusion pattern of Z. japonica plant. A small stock of Z. japonica was planted at the central point of round pot, 65 cm in diameter, containing sand adequately fertilized. After the stolon elongation started, the horizontal diffusion pattern of aboveground part was measured ten times during the growth period by a grid-counting method, and fractal dimensions were calculated. The eight kinds of gridded-frames having different grid sizes from 5 mm×5 mm to 100 mm×100 mm were used here. The frame was placed on the pot to count the number (Ns) of grids containing plant part. The measurement area was limited to a central 40 cm × 40 cm in the pot. When one side length of grid is s, fractal dimension (D) is given by Eq. (1). Ns=k・s^<-D> k,const.……………(1) Fractal dimension is presented as the decline (D) of regression line obtained between s and Ns in log scale. Fractal dimension of Z. japonica could be accurately determined by the grid-counting method. Fractal dimension of Z. japonica rose with elongation of stolons and presented a seasonal variation. No statistically significant relationship existed between fractal dimension and dry matter production in plant. Mowing treatments caused the fractal dimension of plant to keep high and constant. We tried to get a more simple measurement method to determine the fractal dimension of Z. japonica. The relationship between D and Ns was presented as Eq. (2), when the 20 mm-gridded frame (40 cm×40 cm in area) was used for measurement of Ns, D=0.0021・Ns+1.22……………(2) Fractal dimehsion was estimated by substituting the value of Ns measured to Eq. (2). More accurate evaluation may be made for the form and structure of a plant and plant population by measuring fractal dimension in addition to other scales generally used.

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The effect of temperature on seasonal changes in dry matter productivity in Napiergrass, Pennisetum purpureum SCHUMACH, cv. Merkeron, was investigated among tillers under two different altitude locations in Miyazaki prefecture. At Kitagawa, 640 m above the sea level, crop growth rate per plant was lower in June, while it increased noticeably in July to be higher through September than that at Miyazaki, 10 m above the sea level. This shows the compensatory growth at Kitagawa in the higher temperature condition in July due to the increase of net assimilation rate (NAR) and leaf area index. This increase in NAR of whole plant at Kitagawa was due to the increase in NAR of primary tillers in July and of secondary tillers in August and September. The variation of dry weights (tiller DWs) among tillers increased with the growing days at Miyazaki, especially so in primary tillers. The variation of tiller lengths among tillers was smaller than that of dry weights. In August and September, the less the tiller DWs, the larger were the NARs of individual tillers at Kitagawa, while the situation was reversed at Miyazaki. At Kitagawa where the growing temperature was lower, the variation of the NARs among tillers was smaller than that at Miyazaki and the NARs increased as the tiller DWs decreased, resulting in the higher NAR per plant during the later growth stage.

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Under a regime of frequent cuttings, seasonal productivity of temperate grasses was followed for five years and the relationship between the productivity and weather was investigated. Six replicated blocks of perennial ryegrass (Lolium perenne), orchardgrass (Dactylis glomerata), tall fescue (Festuca arundinacea), Kentucky bluegrass (Poa pratensis), red top (Agrostis alba), and red fescue (Festuca rubra) were sown in September 1984. Each species was divided into three groups, the first group was cut in the next early spring, and the second group cut a week after, and the third group cut two weeks after the first cut. All of the groups were cut at three-week intervals thereafter. Each species in the three groups was cut every week during the growing seasons (30 times a year) from 1985 to 1989, and top-dressed with 20 kg N+10 kg P_2O_5+17.5 kg K_2O/ha per cutting. The changes in seasonal productivity of temperate grasses had three peaks and two bottoms in the average values over five years. The peaks were around the middle of May, July and September, and the bottoms were around the middle of June and August, respectively. The first peak was high and the third peak was low or obscure every year, but the height of the second peak was greatly affected by the precipitation during the season in each year. The depth of the two bottoms was greatly affected by dry weather. Perennial ryegrass and Kentucky bluegrass were less resistant to drought. Total production over five years was high in orchardgrass and perennial ryegrass, and the productivity during autumn was high in perennial ryegrass. It seems that perennial ryegrass might be the most valuable species for frequent grazing in this area, though it needs careful management to maintain high productivity and requires combined use with some drought resistant species.

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