Heat pulse method is an effective method for measuring sap-flow in stem of trees and vegitables under field condition. It is generally considered hard to use this method for the grasses having short and slender stems because stems are injured. The experiment for examining the application of the heat pulse method to some grasses was carried to clarify the plant-water relationship in Japanese millet (Echinochloa utilis Ohwi et Yabuno), sorghum (Sorghum bicolor Moench) and maize (Zea mays L.). 1) The velocity of sap-flow in stem, evaluated by the heat pulse method, was closely related to the water loss due to the transpiration expressed by means of weighing. Linear relationships and positive correlations were observed in all species between the velocity of sap-flow and transpiration rate. And the deviation of observed points from the regression line were less than about 10 percent for all range (Fig.3). 2) All species had similar patterns in the diurnal courses of the sap-flow velocity. The sap-flow velocity increased rapidly with increasing solar radiation in the morning, and reached at the highest level in around midday, then declined gradually with decreasing solar radiation (Fig.2). 3) The velocity of sap-flow was closely related to the factors affecting transpiration, such as stomatal aperture, stomatal conductance, leaf temperature and light intensity. There were positive correlations among these transpiration factors with each other (Table 1, Fig.4). 4) These results indicate that the heat pulse method is suitable for the study of water consumption in individual plant of Japanese millet, sorghum and maiz grown under field condition.

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For evaluating relative drought sensitivity of seven tropical pasture legumes ; Macroptilium atropurpureum cv. Siratro, Stylosanthes humilis cv. Townsville, S. guianensis cv. Schofield, Desmodium intortum cv. Greenleaf, D. uncinatum cv. Silverleaf, Nenotonia wightii, cv. Tinaroo, and Centrocema pubescence, plant DM weight, leaf area, leaf water potential, transpiration rate, and diffusion resistance were compared with the plants grown in the irrigated field and in the dry field. Ratios of the plant top weight decreased with decreasing soil water levels in all legumes, however, leaf area per plant top weight increased in Greenleaf and Silverleaf whereas decreased in the other legumes, suggesting greater potential of the latter legumes in the water-up-take in drier fields. Greater plant root weight were recorded in Centro and Siratro. Ratios of plant root weight increased in Schofield and Townsville in addition to the above two legumes, but decreased in the three other legumes, suggesting greater potential of the former legumes grown in drier fields. Differences in leaf water potential of the legumes grown in the irrigated field and in the dry field were of decreasing order of (1) Schofield, Townsville and Siratro, (2) Centro, Greenleaf and Silverleaf and (3) Tinaroo suggesting relative drought tolerance in this order. Greater diffusion resistance and lesser transpiration rates were observed in Tinaroo, Silverleaf and Greenleaf grown in the dry field. The above results suggest that the legumes such as Siratro, Townsville, Schofield and Centro have greater drought tolerance derived from greater ability of extending root systems and of decreasing either plant top weight or leaf area per plant under limited soil water conditions.

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To evaluate the potential of tropical pasture legumes for increasing pasture productivity in the southern parts of Sowth-Western Islands, Japan, dry matter production of three cultivars of Stylosanthes spp. grown in mixture with three tropical pasture grasses were compared under two clipping intervals over two years. The cultivars and the grass species used in the experiment are ; S. humilis cv. Townsville, S. guianensis cv.'s Endeavour and Schofield, C. gayana cv. Pioneer (Rhodes grass), P. maximum (Guinea grass, unknown cultivar), and S. anceps cv. Kazungula. Annual dry matter production amounted 11.5-15.0t/ha in the stands of Endeavour and of Schofield mixed with the grasses showing a potential future for growing in the southern parts of South-Western Islands, Japan, however, the mixtures of Townsville and the grasses were not promising. Annual dry matter production of the mixtures of the promising legume cultivars changed with the growth habit of the associated grasses: Increased production levels were obtained with shorter or longer clipping intervals in association with longer or shorter type of grasses, respectively. The estimated optimal growing temperature for the promising legume cultivars were at 27-8℃ suggesting increased levels of legume effects on increasing productivity during worm seasons of this area.

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The problems on pasture fences constructed in the highland were pointed out by investigating the actual conditions. The results are summarized as follows ; 1) Steel line posts tipped, dug up or sunk into the ground, and small hooks sheared were observed at the corner of the pastures, along the small valleys, on the uneven places and beside the heaped stumps (Fig.3). The rate of the defects was 6% of all the line posts. These defects caused the wire to loosen or fall off from the posts, and might be one of the factors that the cattle escaped through the fences. 2) Many corner posts were tipped forward or backward, although they were fixed with the props. It is supposed that the depth of the corner posts driven into the ground was shallow and the point of driving props was wrong. 3) The barbed wire was fixed to the line posts with T-shaped plates at the time of fence construction (Fig.2). However, when the fences needed to repair after wintering, repairs were made mainly by tying with short wire or hanging the wire on the small hooks of posts, instead of using plates. 4) The rate of wire covered with soil or dead grass material and touched on the ground was 32% of all the lower wire. These occurred mainly on the wire loosened or fallen off from the posts. 5) From these surveys, the snow damage and the lack of soil bearing capacity seemed to cause the results mentioned above and their damage differed according to places where the fences were installed. It is necessary for planning the fence constrution to adopt a method corresponded to the topographical conditions.

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Algal nitrogen fixation in grassland was investigated by using acetylene reduction method. Nostoc sp. crusts grown in the mixed grassland of shiba (Zoysia japonica) and common lespedeza (Kummerowia striata) showed the acetylene reducing activity (ARA), and its activity was about the same level as that of common lespedeza on the basis of unit area of the grassland. However, the activity in units per gram of fresh weight was about 1/10 in compare to that of common lespedeza root and was only 1/800 to that of the nodules, respectively. Besides, it was observed that the ARA of Nostoc sp. crusts was higher under the light condition than the dark one. Although Nostoc sp. crusts in grassland were in the wide ranges of water contents (98-31%) and the ARA appeared to highly correspond to their water content, the highest activity was recognized at about 25% of water content under laboratory condition. The rewetting treatment to the dried Nostoc sp. crusts made their ARA increase rapidly beyond expectation. It was proved from this investigation that algal nitrogen flxation such as Nostoc sp. crusts was one of the important factors affecting nitrogen input into grassland and their activity was mainly restricted by water supply to their growing sites.

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Waterhyacinth (Eichhornia crassipes) is known to be one of the most troublesome weeds in the world. This aquatic plant grows actively and rapidly, and produces dense monospecific stand which often covers the water system in the tropical and subtropical regions. In recent years, it invaded the water system in the southwestern part of Japan since water became enriched with various wastes from agricultural fields, residences and industries. However, no effective treatment has been worked out to control this plant. In this paper, the possibility of utilizing waterhyacinth as feedstuffs was discussed by determining nutritive characteristics of this plant. Samples were collected monthly from June to November from three places ; Nishinoko (Azuchi, Shiga), Ogura (Kumiyama, Kyoto) and Kyoto University (Experimental pool, Kyoto). After harvesting, the plants were washed and divided into the upper part (green part) and the lower part (mainly roots) and were determined for dry matter, organic matter, crude protein, crude fat, carbohydrate, crude ash, NDF and gross energy. Cell wall constituents (CW) in the upper part and their in vitro digestibilities were also determined. Waterhyacinth contained water as much as 93 per cent in fresh matter, which frequently made it difficult to handle this plant as feeding materials. This plant might be susceptible to be decomposed in a trough in hot and humid season. Pre-conditioning, prior to be ensiled, seems to be hard because of its high water content. Nutritive value of waterhyacinth varied widely among the places and significant differences (P<.05) were found in the contents of organic matter, crude protein, carbohydrate, crude ash, NDF, gross energy and in vitro CW digestibility among the plants collected in these three places. It showed that waterhyacinth seemed to be susceptible to the environmental conditions on which this plant was grown. The characteristics in feeding components of waterhyacinth were high contents of crude ash which ranged from 11.8 to 20.0 per cent in dry matter and relatively high contents of crude protein of 12.3 to 19.5 per cent in dry matter. Among them, crude ash and crude protein contents (dry basis) were remarkably high in the plants obtained from Ogura, where pollution problem in drainage was serious. Seasonal changes of nutritive values during growing season (June to November) were very small when compared with those of grasses and legumes grown on the fields. But, organic matter and carbohydrate contents in the dry matter of waterhyacinth were slightly low and crude ash contents were high in June, July and August. Therefore, gross energy contents seemed to be low at that time. The upper part of the plants contained more crude protein, crude fat and crude ash and less organic matter, carbohydrate and NDF than the lower part. But the content of gross energy of the upper part was almost equal to the lower part. CW contents in the upper part of the plant were about 70 per cent in dry matter during June to Octover. However, it decreased to 65 per cent in November and their in vitro digestibilities were remarkably low in November when it became cold and the plant began to be blasted. Though nutritive value of waterhyacinth varied widely among the places and also this plant contained much water and crude ash, small changes in the nutritive values during the growing season and high content of crude protein in dry matter seemed to be desirable characteristics of this plant as feedstuffs.

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This study was conducted to determine if the types and varieties of paddy rice (Oriza sativa L.) under different fertilizer application are related to herbage yield, silage quality and feeding value. Two Japonica varieties (Kinmaze and Matsuyamamii), three Indica ones (Ambar, British Honduras and Gaiya Dhan Tosar) and Sen one belonging to Chinese paddy rice (Peikuunen) were used for this examination. Those paddy rice were transplanted in submerged paddy field and then, hervested at the milk-ripe stage for whole crop silage. Each silage quality was estimated by the FLIEG's method and each digestibility of chemical composition was also examined by the conventional collection trial with three sheep. The results are summarized as follows. 1) The Indica varieties including Peikuunen ripened earlier and had longer culm than the Japonica one. Peikuunen and the Indica varieties except British Honduras at the ripenning stage lacked in ability of lodging resistance. The fresh forage yield was more in the Indica varieties including Peikuunen than in the Japonica ones. However, dry forage yield was more in the Japonica varieties and Peikuunen than in the Indica ones. Matsuyamamii, the Japonica varirty, which showed the highest yield among varieties was about 145kg of dry forage yield per are in heavy dosage of fertilizer application. 2) The contents of NFE and water soluble carbohydrate of the Japonica varirties in ensiled material were higher than those of the Indica ones including Peikuunen. While the crude ash and SiO_2 contents of the former was lower than the those of the latter. 3) The silage qualities were ranked either "excellent grade" or "good grade" by the FLIEG's method. Each silage quality of the Japonica varieties and Peikuunen was supperior to that of the Indica. 4) The digestibilities of crude protein and crude fiber were higher in heavy fertilizer application than in standard one. Each NFE digestibility of Gaiya Dhan Tosar showed the lowest value among both fertilizer treatments examined. 5) DCP content of silages were higher in heavy fertilizer application than in standard one. TDN contents ranged from 49.5 to 58.2% in standard fertilizer application and from 54.4 to 58.9% in heavy one. 6) TDN yield of silage ranged from 43.2 to 61.3kg per are in standard fertilizer application and from 51.1 to 75.2kg per are in heavy one. The digestible nutrient yield (TDN) of the Japonica varieties were higher than those of the Indica ones. 7) This study has shown that silage of the Japonica varieties and Peikuunen were higher forage yield and digestible nutrient yield than those of the Indica ones, but, Peikuunen at the ripenning stages was lodged easily by visiting of typhoon and evening showers. From above mentioned results, it is recommended that the Japonica varieties with longer culmed and late ripenning, such as Matsuyamamii, suited for whole crop silage of paddy rice in warmer districts of Japan.

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Acid-soluble lignin (soluble in 1N sulfuric acid), which is excluded in the common determination of lignin, and degradability by cellulase were determined on neutral detergent fiber from orchardgrass culms at five different growth stages. The logarithm of acid-soluble lignin content (% hemicellulose) was negatively correlated with hemicellulose degradability (r=-0.963). Acid-soluble lignin ranged from 33% to 66% of permanganate lignin.

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Fresh alfalfa and its fraction (pressed cake, chloroplastic protein fraction (PF-I), cytoplasmic protein fraction (PF-II) and brown skim), and some leaf protein concentrates (LPCs) which were prepared either from a mixture of alfalfa and barnyard grass (LPC A), a mixture of oat and annual meadow grass (LPC B) or ladino clover (LPC C), were subjected to proximate analysis. The above mentioned LPCs and some other LPC samples such as LPC D from ladino clover, LPC E from alfalfa and LPC F which was obtained by washing LPC E with ethyl alcohol, were also subjected to amino acid analysis. PF-I, LPCs A, C, D, E and F were a representative of the chloroplastic protein, PF-II was that of the cytoplasmic protein and LPC B was a mixture of both. PF-II contained 50.1% crude protein, while PF-I contained 43.2%. Fresh brown skim contained only 1.1% crude protein (21.3% on dry matter basis). PF-I and PF-II, respectively, contained 9.8% and 7.7% ether extracts, 6.5% and 6.4% crude fiber, 18.8% and 16.6% crude ash. The protein fractions contained more lipids and less NFE than the corresponding whole material and the pressed cake. Gross energy of each fraction was very similar, being 19-20kJ/g of dry matter. Legume LPC was much extractable compared to grass LPC, and more purified LPC could be obtained by the laboratory scale procedure than by the practical plant scale procedure. Recoveries of the total amino acids from crude protein were 80%, 89% and 79% in whole alfalfa, PF-I and PF-II, respectively. Compared to the soybean protein, alfalfa and its fractions were low in arginine, aspartic acid, glutamic acid, isoleucine, leucine, phenylalanine, proline and serine and high in alanine, methionine and tryptophan. Histidine was 4 times higher in PF-I than in soybean protein, and in the contrast, arginine content of alfalfa protein was almost one-fourth that of soybean protein. Amino acid composition was not so much different among LPCs though there were some fructuations. When compared to the soybean protein, LPCs were high in alanine, glycine and threonine but low in arginine, aspartic acid, glutamic acid and serine.

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The intention of the present study is to make clear the relation between the state of fibrous residues (FR) left after the extration of leaf protein concentrates and the quality of silages prepared from them to establish the ideal conservation method of FR. For the purpose, 25 kinds of FR were prepared from the herbages listed in Table 1 by pressing out green juice from macerated herbages. Every FR was filled in two glass bottles of 800ml capicity at a rate of 500g per bottle. Eight of the 25 kinds of FR were also ensiled in two polyethylene bags (40×60cm) each at a rate of 10kg per bag. Ensiling period was about 6 months. The average volume of removed green juice was 58.2% of the fresh weight of material herbages. The average DM and WSC contents and buffering capacity (BC) of FR were 26.8%, 4.8% DM and 17.2 mequiv./100g DM, respectively. The average concentrations of pH, lactic acid, total VFA and ammonia-N of the bottle silages were 4.15, 2.10% DM, 2.55% DM and 8.2% TN, respectively. Butyric acid was detected only in 3 of the 25 bottle silages. It was statistically indicated that the higher the DM and WSC contents of FR were, silages of the better quality were obtained suggesting that they were the most important factors for the fermentation of FR within the ranges shown in Table 1. The BC of FR had little effect on the silage quality but a significant possitive correlation with the lactic acid content. There were no correlations between the removed juice volume and the silage quality. The correlations among the pH, lactic acid, VFA and ammonia concentration of the FR silages were almost identical with those of conventional silages in spite of attaining low pH value with the lower acid concentrations in the former. The quality of bag silages was compared with those of the bottle silages prepared from the same materials and there was found a sighificant correlation between them. It is concluded that silages of good quality can usually be made from FR left after the extraction of more than 5l of green juice from 10kg of herbages and containing about 30% DM.

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For determining the vegetative factors affecting the yields of leaf protein concentrate (LPC), fibrous residue (FR) and brown juice (BJ) in the fractionation of green crops, the relation between the composition of material crops and that of the three process fractions were examined using twice cuts of Italian ryegrass, thrice cuts of lucerne and red clover and single cut of oats. After cutting, the crops were minced with a pulper and then squeezed with an oil-jack press to separate them into green juice (GJ) and FR. The GJ was acidified to pH 4 with HCl, heated to 70℃ and then divided into coagulate (LPC) and BJ through Toyo No.2 filter paper under sucking. The yields of LPC and FR were highly correlated with the moisture, crude protein and crude fiber contents of the crops. The signs of the correlation coefficients were oposite between LPC and FR. The regression equation showed that the moisture, crude protein and crude fiber contents of crops should be over 87% as is, over 20% and less than 24% of dry matter, respectively, to recover more than 12% of the dry matter in LPC. The dry matter distribution in BJ was highly correlated with the moisture content of crops and subsequently with the yields of GJ. When twice or thrice harvests were made, the yields of LPC per acre depended on the yields of crops rather than the kinds of them. LPC contained from 44 to 62% crude protein on dry matter basis regardless of the recovery rates. The composition of FR was highly correlated with that of the crops. As the result, FR from crops ensuring high LPC yield contained enough crude protein for cattle growth. The NFE content of BJ was about 50% of dry matter and significantly correlated with that of the crops.

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Light serves as the main driving force of photosynthesis and therefore has a direct impact on growth and hence dry matter production. Since tropical forages have higher light saturation levels for photosynthesis compared to temperate forages, they are potentially more productive. However, even in the tropics where there is generally high insolation, occassional cloudiness, as occurs in the rainy season may reduce the level of irradiance ; also in some areas there may be the establishment of forages under plantation crops to maximize land use. The persistently high insolation in the tropics has been suggested as a significant contributor to the lower dry matter digestibility of tropical forages. Since dry matter digestibility generally decreases with increase in dry matter yield, it is not clear to what extent these decreases are due to light intensity. Very few experiments have examined the direct effects of insolation on the nutritive value of forages, and the few available have been mainly with temperate forages. Decreasing light intensity is reported to increase the crude protein content as well as the crude fibre content but results in a decrease in non-structural carbohydrate content. On the contrary, decreasing light intensity tends to decrease dry matter digestibility. Thus, this experiment was carried out to study the effect of light intensity on the growth, chemical constituents and digestibility of green panic (Panicum maximum var. trichoglume cv. Petrie).

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Two pot experiments were conducted to find out whether soil media and soil particle size could affect the growth and curvature of seminal roots of Zea mays L. seedlings. In experiment 1, seeds of cv. Great Bell were germinated and the young seedlings with straight seminal roots 30±1mm in length were collected. Tops were cut off at mesocotyl and transplanted to 1/5, 000 a plastic pots filled with moistened clay soil with different soil particle sizes ; 0.59-0.84mm, 0.84-2.38mm, 2.38-4.76mm, 4.76mm and over. Seedlings were covered with a thin layer of clay soil and grown in controlled room at 22+1℃ under darkness for 96 hours. In experiment 2, clay soil-screened through a riddle of 1cm, sand and vermiculite were used as soil media. Preparation of seedlings and growing condition were same as experiment 1. Decapped plots were added in this experiment by removing the root caps of the seminal roots of the seedlings. In experiment 1 roots grew more and fewer roots curved in the clay media of larger particle size than in those of the smaller size. In experiment 2 roots grew most with few curved roots in vermiculite as compared to those in other media, suggesting that the roots are sensitive to the hardness of root media. Decapped roots grew less than control roots in all three media examined and curved in clay or sand, in contrast to the straight growth in vermiculite.

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In a series of studies on paddy as a feedstuff, the feeding value of grain was investigated. The varieties used were Nihonbare and Suigen 258 (Suigen). In order to estimate the digestibility of grain, sheep were used in a conventional total collection trial. Materials of the digestion trial were rough rice, unpolished rice and crushed rough rice. Both DCP and TDN contents in rough rice and crushed rough rice of Nihonbare were higher than those of Suigen. But, DCP and TDN contents of unpolished rice were higher in Suigen than in Nihonbare.

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Near-infrared reflectance analysis (NIR) was applied to orchardgrass variety test (four cultivars, four replications). Correlation coefficients of 0.93-0.96 were obtained between NIR and laboratory analysis in predicting the contents of crude protein, ether extract (EE), neutral detergent fiber (NDF), acid detergent fiber, lignin, and in vitro NDF degradability. Prediction was more accurate for finely ground samples than for coarsely ground ones. NIR required 3min per sample for prediction. NIR detected the least significant difference in the contents between cultivars as effectively as laboratory analysis except in EE and NDF. We concluded that NIR is an accurate and rapid method of predicting quality in forage variety test.

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