On the inland slopes of NSW, Australia, native grass dominant pasture has been the main feed source for sheep and cattle, mainly due to the dry climatic conditions. An attempt was made to introduce temperate improved pasture species, and to lift the low production level of a commercial scale farm, "St. Helena" using L. perenne, T. repens, T. subterranium, and D. glomerata as the main species. A flexible rotational grazing system was introduced in order to maximise utilisation of the improved pasture. The results indicated a three-fold increase in pasture productivity, and that stock performance twice as high as the average farm production level is potentially achievable in the region. They also indicated that the balance of native grasses, improved pasture species and legumes should be at an approximately equal ratio of 30% each to achieve such a goal.

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Some soil physical and chemical properties of five well-developed natural kudzu (Pueraria lobata OHWI) stands, and two Robinia pseudoacacia forests and one Myrica rubra forest for comparative purposes were investigated as a part of a study on the characteristics of the "plant community-soil system" at the early stage of regenerated vegetation in places where the secondary forest in the lucidophyllous forest zone was destroyed by fire. This study was conducted in Motoyama-cho, Higashinada-ku Kobe ; at the southernmost part of the Paleozoic strata in the Mt. Rokko disrict. Kudzu stands in the study area have generally developed in places where the degree of soil compaction was high and the other plant species are hard to establish : spur ends, the bottom of gorges and steep slopes. The kudzu stands studied, like the R. pseudoacacia forests distributed widely in the study area, were established on the eroded soil of brown forest soil type resulting from the repeated destruction of "plant community-soil system". The kudzu stands had a total above-ground dry weight of 526.8 g m^<-2> at Plot 3. The Kudzu stands was inferior in the physical and chemical properties of the in 0-30 cm depth soil (soil in absorbing root zone) and had a similar percentage of soil water content (30-40%) to the adjacent R. pseudoacacia forest and M. rubra forest. From the results of this study, it is assumed that kudzu stands established in the sites with a higher degree of soil compaction on steep slopes maintain nearpure stand status in a "plant community-soil system" for a relativeIy long time.

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Mycelium characteristic of endophytic fungi belonging to Acremonium sect. Albo-lanosa was present in seeds of tall fescue from 14 of 39 ecotype collections made throughout Japan. The characteristic mycelium was also detected in one of seven pasture-type commercial cultivars. However, intercellular hyphae were present in the leaf sheaths of plants from only two of the 15 infected seed samples, indicating that the fungus in the other thirteen samples was dead. The death of the fungus probably ocurred because the seeds were stored for 5-7 years after being harvested. The hyphae were detected in tillers of tall fescue from 6 of 9 turf-type cultivars, and their infection rates were 55-90%. The hyphae in the leaf sheaths of infected plants were hyaline, convoluted, infrequently branched, and ran parallel to the vascular bundles. Examination using scanning electron microscopy confirmed that the hyphae were located in the intercellular spaces. Morphological changes such as cell collapse were not observed in the host cells adjacent to the hyphae. Tissue pieces taken from infected tillers and incubated on potato dextrose agar consistently gave rise to slowgrowing white cottony colonies with numerous solitary slender tapering phialides on the aerial hyphae. Each phialide usually produced just a single, non-septate, hyaline, smooth-walled, ovoid to reniform conidium, 6-12μm (mean 10.5μm)×1.3-3.9μm (mean 2.5μm), typically positioned at right angles on the tip of the phialide. All isolates obtained were identified as Acremonium coenophialum MORGAN-JONES et GAMS as reported in tall fescue in many countries.

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Two experiments were carried out to investigate the release rates of macrominerals as a factor affecting the efficiency of minerals in forage by ruminants. The quantitative analysis of minerals was determined with X-ray counts by an energy-dispersive X-ray (EDX) analysis. Cross sections of leaves of three grass species were soaked in water for 5 minutes to 12 hours. Mineral release rate was expressed in terms of percentage calculated from differential values between EDX data of original samples and those of water-soaked samples. In elemental composition of original sample. Si was the most predominant element and followed by K and Cl. Almost all of the mobile elements were released in less than one hour in water. Release percentage was highest in K. It was medium in CI and Ca, low in S, P and Mg, and lowest in Si. Varietal differences in the watersolubility of minerals were variable among the experimental years. Significant differences among plants in the release of most elements were obtained, while the differences among plant parts appeared to be small.

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Recently it has been reported that percent Brix of stalk juice is applicable to indirect estimation of stover digestibility in forage corn. In this study, additive and dominant effect for percent Brix of stalk juice and estimated stalk sugar content (ESSC) were estimated by means of generation mean analysis for P_1, P_2, F_1, F_2, B_1 and B_2 generations of two crosses : Na26(flint)×Oh43 Ht (dent) and Na7 (dent)×Oh43Ht. Percent Brix was measured at the internode just above the top ear and ESSC was calculated as follows. ESSC=[(FW-DW)×percent Brix/{(100-percent Brix)×DW}]×100 where, FW=fresh weight, DW=dry weight. The relationship between percent Brix and ESSC was also investigated to clarify the effect of correction of percent Brix with dry matter content. Estimates of additive effect were approximately three times as large as dominant effect in both traits and both crosses. Estimates of dominant effect were small in both crosses and not significant in Na 26×Oh43Ht. Percent Brix was highly correlated with ESSC in segrigating generations, although the correlation were somewhat lower when percent Brix was higher than 9 to 10%. From the above results, it is inferred that selection of genotypes with high percent Brix of stalk juice is rather easy and percent Brix of F_1 hybrids is almost equivalent to the mid parental values. In indirect selection of stover digestibility, however, it is desirable that the preparatorily selected materials with high percent Brix are re-evaluated by ESSC.

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This study was made to obtain some information on the spring regrowth of summer-planted napiergrass (Pennisetum purpureum SCHUMACH) subjected to different cutting dates and heights before overwintering. The plants were cut to -3,0 or +20 crn in early December in Experiment 1, and to 0 or +20 cm in late October or late November in Experiment 2. Plant characteristics before and after the overwintering were measured with a particular attention to the individual tillers and tiller buds. The regrown percentage of plant and the dry weight (DW) of regrown tillers in May increased as the cutting height was raised and the cutting was delayed. Increasing the cutting height raised the number of tillers grown from the overwintered tiller buds (RT_<otbs>), owing mainly to the increase in the survived percentage of emerged tiller buds (SPETB) and the total number of tiller buds. Delaying the cutting date, in contrast, raised the number of daughter tillers of RT_<otbs>. Death, survival and regrowth of the buds were dependent on the position of the buds in the soil. The dead tiller buds were located in the shallowest position, and the survived tiller buds were in the deepest position. The regrown tillers were in an almost intermediate position. There was a highly significant positive linear relationship between the SPETB in early April and the regrowth percentage of plant in early May, which indicated the importance of the SPETB to the spring regrowth of napiergrass.

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A 60-week long storage experiment was conducted to determine carotenoid stability on freeze-dried alfalfa (c.v. Natsuwakaba) leaf extract treated with various antioxidants during herbage processing. The antioxidants used were ethoxyquin (ETX), sodium metabisulfite (MBS), butylated hydroxyanisole (BHA), ascorbic acid (AA), α-tocopherol (AT) and tea leaf extract (TLE). Each leaf extract was divided into six portions and allocated into 2 clear and 4 amber coloured glass jars. One clear and 2 amber jars were flushed with nitrogen gas while ordinary air head space prevailed in the other three jars. The amber jars were kept under two storage shemes ; (a) 12-h constant lighting provided by 16 pieces of 40W fluorescent lamps with temperature controlled at 28℃ and (b) in a freezer (-18℃) without exposure to light. The clear jars were kept only under storage scheme (a). Low temperature protected the xanthophylls regardless of treatments of antioxidants but did not protect effectively β-carotene without ETX under long-term storage. At 28℃, both β-carotene and xanthophylls were degraded but the rate was far reduced by treating with ETX and keeping in amber coloured jars. With these treatments, about two-thirds of the values at 6-week storage were recovered after 60 weeks. Nitrogen gas flushing had no significant effect. Butylated hydroxyanisole, MBS and TLE could be alternative antioxidants but only for short-term storage. α-Tocopherol and AA did not prevent the decomposition of carotenoid at all. The study showed that addition of ETX during herbage processing and storing the leaf extract at low temperature (-18℃) gave the best protection for carotenoids. The best protein yield was also obtained in ETX treated leaf extract.

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This study was carried out to investigate the fermentative quality and nutritive value of napier grass (Pennisetum purpureum Schum.) ensiled with wheat-mill-run (WMR). Two batches of napier grass, which were harvested in July (dry matter (DM) : 11.4%) and in September (DM : 16.5%) for 1st cutting, were ensiled with and without 15% of WMR at fresh grass basis. Silage effluent was found only in the silage ensiled without WMR in the harvest in July, but not found in the silage ensiled with WMR and in silages from the harvest of September. Wheat-mill-run supplementation decreased pH value of the silage on July, and decreased acetic acid content and ratio of ammonia-nitrogen to total nitrogen of silages in both July and September. In feeding trials by goats WMR was supplemented to the silage ensiled without it, so that intakes of the ensiled grass itself and WMR were the same between groups fed the silage ensiled with and without WMR. Digestibilities of organic matter, dry matter, crude protein, neutral detergent fiber and acid detergent fiber, and nitrogen retention were lower in goats fed the silage ensiled with WMR than those fed the silage ensiled without WMR and supplemented it at feeding. Retained nitrogen over absorbed nitrogen by goats was significantly (p<0.05) lower in goats fed the silage ensiled with WMR than those fed the silage ensiled without WMR. These results were thought to come from the higher ammonia nitrogen concentration in ruminal fluids in the former group of goats. Wheat-mill-run supplementation to the napier grass of high moisture content was effective in reducing the silage effluent, but it was accompanied by a reduction of nitrogen utilization of the silage in goats.

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Germinating behaviors of legume were observed to characterize the establishment of seedlings grown on the soil surface. Seven legume species ; white clover (Trifolium repens L.), alsike clover (T. hybridum L.), red clover (T. pratense L.), crimson clover (T. incarnatum L.), birdsfoot trefoil (Lotus corniculatus L.), alfalfa (Medicago sativa L.), and common vetch (Vicia sepium L.) were sown on the Yellow paddy field soil surface under controlled conditions at 25℃ and 100% RH. Some morphological characteristics of taproot in relation to the germinating behavior were measured in legume seedlings. 1. Elongating taproot pushed the seed backwards grew without penetration of the tips. After root hairs developing on taproot adhered to the surface and seedling anchored that place with root tips penetrated into the soil. 2. Germinating behaviors were classified into following three types owing to adhering rate in the length of taproot hair developing zone. Type 1. Taproot hairs that developed initially adhered to the soil surface, thus taproot grew in contact with the soil surface and root tip penetrated into the soil (contact-adhesion type). Type 2. Taproot hairs adhered partially to the soil surface, a part of taproot was not in contact with the surface but root tips penetration (partial-adhesion type). Type 3. Taproot hairs failed to adhere to the surface, then taproot was not in contact with the soil and failed to penetrate into the soil (non-adhesion type). 3. White clover and birdsfoot trefoil had higher percentage of contact-adhesion type in germinating behavior. Alsike clover, red clover, crimson clover and alfalfa had higher percentage of partial-adhesion type. Common vetch had higher percentage of non-adhesion type. 4. Percentage of contact-adhesion type seedlings was related significantly to the ratio, i.e., the length of root hair to root diameter in legume species used (r= 0.873, p < 0.05). In all the species used, the adhering area that has been bound on the soil surface by taproot hair was significantly larger in contact-adhesion type than in partial-adhesion type. 5. On the basis of the present results, an adhering function of taproot hairs in surface-sown legume seedlings may secure good penetration of root tips before establishment can be achieved.

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Seeds of seven legume species, white clover (Trifolium repens L.), alsike clover (T. hybridum L.), red clover (T. pratense L.), crimson clover (T. incarnatum L.), birdsfoot trefoil (Lotus corniculatus L.), alfalfa (Medicago sativa L.) and common vetch (Vicia sativa L.), were surface-sown on the Yellow soil surface under controlled conditions with 25℃ and 100% RH. Penetration percentage of taproot tips, mean days for taproot penetration, and hypocotyl and root growth of three adhesion types in germinating behavior were examined for five days to decide the adhering function of taproot hairs. The three adhesion types in legumes were contact-adhesion, partial-adhesion and non-adhesion type owing to adhering degree in the length of taproot hair developing zone. 1. Ninety percent of taproot tips of contact-adhesion type in white clover, alsike clover, birdsfoot trefoil and alfalfa penetrated into the soil, being significantly higher than that of partial-adhesion type. The same tendency was observed in germinating behavior in red clover, crimson clover and common vetch. 2. The mean day for taproot tip penetration of contact-adhesion type was shorter than that of partial-adhesion type in all species examined. Length and proportion of taproot exposing on the soil surface were shorter in contact-adhesion type than in partial-adhesion type. 3. The hypocotyl-root ratio in length was highest in contact-adhesion type, followed by partial-adhesion type and non-adhesion type. Therefore, good adhesion of taproot hairs to the surface enhanced the hypocotyl growth as compared with taproot growth, and poor adhesion of taproot hairs enhanced taproot growth. 4. Based on the present results, contact-adhesion type in germinating behavior would provide good establishment compared with partial-adhesion and non-adhesion type.

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A field experiment was undertaken to clarify influence of summer grazing by beef cattle on successional process in a Sasa nipponica grassland. Coverage and height of plant species were measured yearly in thirty-six permanent quadrats on the grassland. Using the coverage and height, state of vegetation was defined for each quadrat with a single-species dominant. At the beginning of the experiment, the grassland was predominantly covered with Sasa nipponica and secondarily with Quercus serrata, containing limited amounts of Artemisia princeps and several kind of deciduous broadleaved trees. Twelve states, in which bare ground was included, were classified during the whole study period. Transition probabilities between the states were estimated. A Markovian model was applied to the probabilities. The successional process had a tendency to return to the former deciduous broadleaved forest consisted essentially of Quercus serrata and Castanea crenata, going through multiple passways. It was shown clearly that Sasa nipponica declined rapidly during three years from the beginning of cattle grazing, herbs increased slightly up to the third year and then decreased gradually, bushes increased rapidly up to the second year and then turned to gradual rise, and trees increased consistently during the period of experiment.

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In the Trifolium repens population which has been patchily distributed in a Zoysia-type sward, seed production in those patches is an important process in maintaining the population size. In this paper, we examined the nature of pollinator behavior in T. repens patches and its consequences to seed set. Following questions were addressed : (1) Does visitor abundance in individual patches increase with number of flower-heads at flowering in a patch? (2) Does average seed set per patch increase with number of flower-heads at flowering in a patch? (3) Are significant differences in pollinator attractiveness found among flowering stages at flower-head level? We observed pollinator behavior in 10 discrete patches of T. repens and examined seed set 3 weeks later. The most important pollinators were solitary bees. Visitor abundance in individual patches increased with number of flower-heads in a patch (r = 0.982, P <0.01). Averaged data of all patches, mean number of seeds per pod and pod set were 0.472 and 27.4%, respectively. No significant relationships were found between these parameters of seed set and number of flower-heads at flowering in a patch. Significant differences were found in pollinator attractiveness among flowering stages of flower-head : flower-heads at peak flowering were more attractive to pollinators than those at early flowering. Above facts suggest that (1) visitor abundance is different among patches, depending on number of flower-heads at flowering, (2) large patches with more flower-heads at flowering synchronously do not always have higher seed set, and (3) pollinators are likely to select individual flower- heads according to their stages of flowering as well as patches.

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This study investigated the spatial distribution of herbage mass in a paddock of a bahiagrass pasture grazed rotationally by beef cattle and mown for hay. With a single-probe electronic capacitance meter, the herbage mass was estimated non-destructively in 5036 fixed places in a 0.61 ha paddock on nine dates during a period of about four months. The statistical parameters of the frequency distributions of herbage mass showed variable responses to grazing, resting and mowing. From the results of the present and past studies, the increase in the coefficient of variation (CV) with grazing, the increase in the mean and decrease in the CV with resting, and the decrease in the mean, maximum and standard deviation (SD) with mowing were regarded as the general phenomena. In the paddock, the areas of lower herbage mass and those of higher herbage mass tended to aggregate in particular parts of the paddock. Furthermore, there were some similarity and dissimilarity in the distribution patterns. The causes for such phenomena were partly cleared by evaluating the comparative contributions of the preceding distribution of herbage mass, grazing equipment and mowing to the herbage mass distribution. The preceding distribution of herbage mass was more important than the grazing equipment in a heterogeneous herbage mass environment. The period for which the effect of the preceding distribution continued was estimated at about 10 to 50 days. The mowing did not always cancel the effect of the preceding herbage mass distribution.

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This experiment was conducted to find the effective use of whole crop silage of rice plant (WCSRP) by examining the feeding value of WCSRP with different relative amount of concentrate and urea supplement. Six experimental plots were set up ; i. e., 10 : 0, 6.5 : 3.5 and 7 : 3 proportions of WCSRP and calf-feeding concentrate on dry matter basis with or without supplement of 2% urea per dry weight. All mixed rations were fed freely. The trials of digestion and nitrogen retention were designed using two 3×3 Latin square methods. Dry matter intake was greater in higher proportion of concentrate ration but did not affect with urea supplement. There was no significant difference in the digestibilities of dry matter and NDF among treatments. An apparent digestibility of crude protein was relatively higher by urea supplement, particularly in WCSRP feeding alone, where a remarkable effect of urea supplement was observed. Nitrogen retention was greater in higher concentrate feeding, but little effect of urea supplement was observed in all ratios of WCSRP and concentrate. The effect of urea supplement on improving nutritive value was not clear in all combine feedings of WCSRP and concentrate. Acetic acid concentration (mol%) in rumen liquor was reduced by urea supplement in WCSRP feeding alone. Concentrations of ammonium-N in rumen liquor and urea-N in blood plasma increased remarkably by urea supplement.

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The harvesting system for making rolled big bale silage by wrapping has been prevailing rapidly in Japan. It is pointed, however, that the quality of the wrapped silage is unstable. This study was carried out to clear the characteristics of wrapped silage and to investigate the conditions for processing high quality silage. 1. Using five grasses ; Italian ryegrass (Lolium multiflorum Lam.), Sudangrass (Sorghum sudaense (Piper) Stapf.), guineagrass (Panicum maximumJacq. Var. maximum ), Rhodesgrass (Chloris gayana Kunth.) and grass mixtures, the relations between moisture content of raw materials and mean dry matter density of rolled bale were investigated. Further, changes of moisture distribution and dry matter density in wrapped roll bales were traced by using a trial sampler of silage. 2. Temperature in the middle of roll bale immediately after wrapping was markedly increased by delay of wrapping. Although temperatures in the surface of wrapped roll bale were varied with the colores of stretched plastic film, they were supposed not to affect so much the quality of silage. Besides, moisture content of raw materials, bale density and breakage of wrapping film affected temperature of the roll bale silage. 3. Four plastic film layers( 50% overwrapping) seemed to be sufficient to store for short term of two or three months, but in long term storage like one year, silage quality was degraded even by six film layers. Two film layers were enough to prevent heat damage of high moisture baled hay. 4. Processing of wrapped roll bale can be applied to wide moisture ranges of raw materials ; unwilted direct-cut grasses to low moisture grasses almost close to hay. It seems, however, to be advantageous to prewilt the materials as much as possible from quality and economical point of view. Simultaneously, it is necessary to increase roll bale density.

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