Specific differences in the variations of growth and N, P and K content during growth period among Rhodesgrass (Chloris gayana), Dallisgrass (Paspalum dilatatum), Bahiagrass (Paspalum notatum), blue panicgrass (Panicum antidotale) and orchardgrass (Dactylis glomerata) grown under the same field conditions were studied as the first step to clarify the characteristics of warm-season grasses in mineral nutrition. 1. The warm-season grasses rapidly increaced plant height and dry matter yield above 20℃ and 25℃ of mean temperature, respectively, while orchardgrass was stunted when the mean temperature exceeded 25℃. Blue panicgrass showed a physiological disorder at about middle of August, probably due to the soil conditions. The highest dry matter yield of each grass was as follows ; Dallisgrass (1, 304g/m^2), Rhodesgrass (895g/m^2), Bahiagrass (832g/m^2), orchardgrass (374g/m^2) and blue panicgrass (297g/m^2). Rhodesgrass reached to the highest yield at the heading stage, while yields of Dallisgrass and Bahiagrass increased at a constant rate for about one month after the heading stage. 2. Although N concentration of each grass generally decreased in the similar manner with the progress of the growth, specific differences in N concentration were found in the following descending order ; orchardgrass>Dallisgrass=Eahiagrass=blue panicgrass>Rhodesgrass until the end of the growth. Specific differences in the largest amount of N contained was found as follows ; Dallisgrass (9.75g/m^2)>Rhodesgrass (8.72g/m^2), Bahiagrass (8.60g/m^2)>orchardgrass (6.64g/m^2)>>blue panicgrass (3.27g/m^2). Dallisgrass, Rhodesgrass and orchardgrass reached to the highest N content about one month earlier than Bahiagrass and blue panicgrass. 3. Phosphorus concentration of Rhodesgrass, Bahiagrass and Dallisgrass decreased gradually with the progress of the growth, but blue panicgrass showed the highest P concentration after the end of September. Specific differences in P concentration were found as blue panicgrass>>orchardgrass>Rhodesgrass>Dallisgrass=Bahiagrass until each grass reached to the highest dry matter yield. The largest amount of P contained in each grass was as follows ; Rhodesgrass (2.88g/m^2)>Dallisgrass (2.61g/m^2)>Bahiagrass (1.96g/M^2), blue panicgrass (1.91g/m^2)>orchardgrass (1.47g/M^2). Phosphorus conten of Rhodesgrass rapidly increased in the vegetative stage as compared with other grasses. 4. Potassium concentration of the four warm-season grasses decreased with the progress of the growth, but that of orchardgrass increased from the end of September. Specific differences in K concentration was found as orchardgrass>Dallisgrass>blue panicgrass>Bahiagrass>Rhodesgrass until the middle of August. The largest amount of K in each grass was found in the order of Dallisgrass (23.2g/m^2)>Bahiagrass (15.8g/m^2)>orchardgrass (11.6g/m^2), Rhodesgrass (10.6g/m^2)>blue panicgrass (5.1g/m^2). Potassium content of Dallisgrass rapidly increased in the vegetative stage as compared with other grasses. The specific differences were discussed in reference to the characteristics of each grass in N, P, or K absorption.

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Specific differences in the content of Na, Ca, Mg, Fe, Mn and Zn and in their variations with the progress of the growth were studied among Rhodesgrass (Chloris gayana). Dallisgrass (Raspalum dilatatum), Bahiagrass (Paspalum notatum), blue panicgrass (Panicum antidotale) and orchardgrass (Dactylis glomerate) grown under the same field conditions. 1. Na concentration of Rhodesgrass varied within 0.28-0.44%, showing the highest concentration in the end of August, while Na concentrations of other grasses varied within 0.02-0.03%, showing no consistent tendency in the variation with the progress of the growth and in the speific differences in Na content among them. The largest Na content of Rhodesgrass (3.7g/m^2) was 10 times or more higher than in other grasses, indicating the strong Na-absorbability of Rhodesgrass. 2. The specific defferences in the variation pattern of Ca concentration with the progress of the growth were not clear. No consistent specific difference in Ca concentration was found throughout the experimental period. 3. The variation pattern of Mg concentration with the progress of the growth in each grass was appeared to be considerably different. Mg concentration of Rhodesgrass was constantly about 0.09% throughout the experimental period and lower than in other grasses at all the sampling time. The largest Mg content of each grass was in the following order ; Bahiagrass (1.96g/m^2)>Dallisgrass (1.65g/m^2)>orchardgrass (1.17g/m^2)>blue panicgrass (0.90g/m^2)>Rhodesgrass (0.81g/m^2). 4. Fe concentration of each grass generally increased in the vegetative stage. The specific differences in Fe concentration were not large, though that of Dallisgrass was relatively low. 5. The variation patterns of Mn concentration with the progress of the growth were different among the species. Mn concentration of blue panicgrass varied within 100-140ppm throughout the experimental period and was considerably low as compared with those in other grasses. In the vegetative stages, Mn concentration of orchardgrass was evidently higher than in the warm-season grasses. The largest Mn content of each grass was in the following order ; Rhodesgrass (390mg/m^2), Dallisgrass (372mg/m^2)>Bahiagrass (289mg/m^2), orchardgrass (157mg/m^2)>>blue panicgrass (43mg/m^2). 6. Zn concentrations of four warm-season grasses were less than 50ppm until the end of September and increased rapidly in the end of the growth period. On the other hand, Zn concentration of orchardgrass was relatively high in the vegetative stage. Zn concentration of orchardgrass was generally higher than in the warm-season grasses, among which were not found a definite specific difference in Zn concentration. 7. There were evident differences in the cation composition between Rhodesgrass and other grasses at around heading stages. The cation compositions were K(45-51%)>Na(21-28%)>Ca(17-20%)>Mg(10-11%) in Rhodesgrass and K(57-71%)>Mg(15-26%)>Ca(10-16%)>Na(1%) in other grasses, among which there were not found marked differences in the cation compositions. Dallisgrass contained relatively higher concentration of K, resulting in the highest value of K/(Ca+Mg): 2.3-2.5 in equivalent ratio. The cation compositions mentioned above were discussed in relation to mineral nutrition of livestocks.

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Vitamin requirements for the growth of timothy leaf spot fungus, Cladosporium phlei de Vries, were examined using the glucose-casamino acid and glucose-NH_4NO_3 media. Thiamine and pyridoxine promoted independently the fungal growth, their effects being remarkable in the NH_4NO_3 medium. When the fungus was cultured in the medium without both of thiamine and pyridoxine, pHs of the kinds of nitrogen sources used. Cultured in the casamino acid medium, the fungus excreted the pigment into the media in nearly equal amounts regardless of the kinds of vitamins added, while cultured in the NH_4NO_3 medium, the fungus did excrete the pigment in large quantity only in the presence of thiamine or pyridoxine.

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The relation between the level of initial air inclusion and the degree of protein breakdown during the early stage of ensilage was studied in conection with the effects of initial air inclusion on quality of silage. In the experiment I, four ensiling trials similarly designed were carried out using four Italian ryegrasses of different crude protein (CP) and water soluble carbohydrate (WSC) contents. In each trial the grass was ensiled at three levels of initial air inclusion of low, middle or high, and non-protein nitrogen (NPN), amino nitrogen (NH_2-N), ammoniacal nitrogen (NH_3-N), pH and organic acids were determined on 1st, 3rd, 7th, 21st and 35th days after ensiling. In the experiment II, two ensiling trials of a same design were carried out. Each trial consisted of (1) control, (2) 100mg% NH_2-N addition at ensiling, (3) 200mg% NH_2-N addition at ensiling and (4) 200mg% NH_2-N+2% glucose addition at ensiling. In each trial the Italian ryegrass was ensiled at the low level of initial air inclusion and levels of NPN, NH_2-N, NH_3-N and organic acids were traced until 35th day after ensiling. (Results are as follows ;) 1. Protein breakdown as expressed by increase in NPN occured mainly during the early stage (until 7th day), and this was brought about by hydrolysis of protein to amino acids. The further breakdown of amino acids as expressed by increase in NH_3-N took place markedly after 21st day of ensilage in some cases and not in others. 2. The first step of protein breakdown as expressed by increase in NPN and NH_2-N occured more rapidly and more heavily at the low level of initial air inclusion than at the middle and the high levels of it. 3. It was suggested that the amino acids accumulated in considerable amounts as a result of heavy protein breakdown during the early stage of ensilage inhibited the production of lactic acid and lowered the quality of silage in such a case as the high CP and low WSC grass was ensiled at the low level of initial air inclusion.

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Seasonal variations of chemical compositions and feeding value of orchard grass hay by the usual methods of hay making in Tokachi district were investigated. The results may be summarized as follows: 1) Evaluating hay quality be based on percentage of leafiness and green coloration, the quality of the 1st cutting hay was a lower grade than that of the 2nd and 3rd cutting hay. 2) In the case of 1st cutting hay, contents of NDF, ADF, lignin and silicic acid were low. The significant negative correlation was observed between content of TDN and contents of ADF, lignin and silicic acid. There were significant correlation between the DDM value calculated with the regression equation showed by Van Soest and the DDM value obtained by digestion trial with sheep, whereas non-significant correlation between the TDN value calculated with the regression equation showed by Adams and the TDN value obtained by the practical digestion trial with sheep was recoginized. 3) In comparison with the 1st cutting hay, the TDN content and DE concentrate of both 2nd and 3rd cuttings hay were low. The DCP content was kept almost constant throughout the 1st, 2nd and 3rd cutting hay were, DCP ; 10.3, 9.9 and 9.8%, TDN ; 65.1, 57.8 and 57.5%, and DE ; 2.96, 2.59 and 2.57kcal/g DM, respectively. 4) In comparison with the 1st cutting hay, digestibility of DM, crude fat, NFE and energy of both 2nd and 3rd cutting hay were low and crude fiber digestibility had a tendency to decreased in the 2nd and 3rd cutting hay. The decreased TDN content of 2nd and 3rd cutting hay was due to decreased digestible NFE content in both hay. 5) In the case of 2nd and 3rd cutting hay, content of crude protein was higher than that of the 1st cutting hay, whereas digestibility of crude protein of the 2nd and 3rd cutting hay had a tendency to decreased. This suggests that, in order to increased nitrogen level in CWC, as is analogized from high value of nitrogen in NDF/total nitrogen in the 2nd and 3rd cutting hay, a large amount of undigestible nitrogen may be excreted in feces. 6) It was found that, in order to make comparison of feeding value of 1st cutting hay with that of after-math growth hay, Van Soest method was very proper method compared to the other method.

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1. Investigations on the analyses of authentic organic acids appearing in silage were carried out by FLIEG's distillation method. When each of lactic, acetic and butyric acid was analysed separately, the values obtained by the above method were reasonable, though some overestimation was observed with lactic acid. Propionic acid was estimated, by FLIEG'S distillation method, as "acetic acid" and "butyric acid" divided roughly in equal amount. When isobutyric, valeric, isovaleric, caproic or isocaproic acid was analysed by FLIEG's distillation method, very high value for "butyric acid", some for "lactic acid" and negative value for "acetic acid" were obtained. This was due to the fact that most of the acid appeared in the first fraction of FLIEG's distillation when a higher VFA was applied to that analysis. When a mixture of the organic acids was analysed, each acid in the mixture appeared in each distillate in the same proportion as when it was analysed separately. 2. Therefore, when a silage extract containing large amounts of higher VFA was analysed by FLIEG'S method, the value for "butyric acid" was higher than the value for the sum of butyric, isobutyric, valeric, isovaleric, caproic and isocaproic acids, and that for "lactic acid" was higher than the true value. 3. Comparison was made on the marks for the silage quality using FLIEG's evaluation key based on the following two methods, i.e. (1) FLIEG's distillation method, and (2) gas chromatography (for VFA) and colorimetry (for lactic acid). In the latter propionic acid was included in "acetic acid" and VFA higher than C_4 in "butyric acid". The marks based on each of the methods showed highly significant positive correlation though, with poor quality silage, the marks based on (2) were slightly lower than those on (1).

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We compared the performances of 18 local strains collected from old pastures and roadsides in Hokkaido with those of 27 verieties from overseas. From these results, the magnitude and the nature of shift caused by natural selection during the domestication. of timothy of Hokkaido local strains were estimated. Hokkaido local strains possess character combinations biased towards the hay type. The following conditions were considered to be responsible for this phenomenon. (1) The original introductions from the United States seemed to have the characteristics of the hay type. (2) Agronomic selection, especially seed production, favored the development of hay type. (3) Climatic conditions, daylength and temperature of early spring, favored hay type. Because of these conditions we suggested that the shift which could be expected during domestication might not be a conversion of major-genic construction but polygenic adjustment. Namely, natural selection favored plant types that produced more seed, while the main agronomic characteristics remained relatively constant. Because most causative factors appeared to be daylength and temperature, the Hokkaido local strains will be a climatic ecotype rather than an agronomic ecotype.

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1. Based on the CO_2 balance of photosynthesis and respiration in the forage plant community, we established the equation by which the dry matter production and crop growth rate (CGR) were estimated mathematically. 2. The relation between the amount of dry matter production and CO_2 balance in the plant community can be expressed by the differential equation (1). dw=P(t)・dt-r(t)・W・dt…(1) p(t), change of the amount of photosynthesis a day in the forage plant community ; r(t), change of the plant respiration rate a day ; W, dry matter weight ; t, day 3. It is possible to consider r(t)=r…const., as the change of r(t) in the growth period is relatively low. Namely, eq.(1) is changed into eq.(6). dw=P(t)・dt-r・W・dt…(6) The change of the amount of photosynthesis a day of the forage plant after cutting is approximated with eq.(2) which indicates the saturation curve. P(t)=α(1-e^<-at>)…(2) 4. Solving eq.(6) by substituting eq.(2) into eq.(6), we can obtain eq.(8) by which the change of dry matter weight of forage plant is calculated. Differentiating eq.(8) with respect to t, we can obtain eq.(9) by which the change of crop growth rate (CGR) is calculated.[numerical formula][numerical formula] 5. In the case of P(t)=P…const. and r(t)=r…const., the dry matter weight and CGR in the plant community are calculated by eqs.(10) and (11). respectively. [numerical formula][numerical formula] 6. If these equations are properly used according to the object of studies, we consider that these equations are useful for analyses of dry matter production in forage plant communities.

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This experiment was performed to examine the chamber method which is a means for measurment of photosynthesis in forage plant population or a sward. Perennial ryegrass (Lolium perenne L.) was used as material in this experiment. Plant was sown on field at early May in 1971 and grown under ordinary fertilizer and soil moisture conditions till late June in 1971. The assimilation chamber made of transparent acryl resin (light transmissibility of 90%) 50cm in lenght, 50cm in width and 40cm in height was designed, and was set on the metallic frame buried in the ground surface of a sward during the measurement. The regulation of the environmental conditions inside the chamber was conducted by controlling the volume of running water on the chamber and of supplying air into the chamber by means of compressor. The measurement of photosynthesis in population was carried out continuously for 6 days from June 30(12:00) to July 6(12:00) by keeping the atomospheric conditions, e.g., temperature, relative humidity, and CO_2 concentration, inside the assimilation chamber similar to those in the sward surrounding the chamber. On the other hand, the amount of dry matter production in the same sward was measured on June 30 and July 6. The examination and the evaluation of the chamber method were made comparing the amount of dry matter production calculated from CO_2 balance with that obtained by direct field measurment during the experimental period (6 days). The following results were obtained. 1) Tne results of this experiment showed that calculated value approximately agreed with observed value of the amount of dry matter production in perennial ryegrass sward. 2) As to the reason why calculated and observed values of the amount of dry matter production were approximately the same, it may be considered that the atomospheric conditions inside the chamber were maintained similar to the sward conditions outside the chamber, that is, the differences of air temperature, relative humidity and CO_2 concentration inside the chamber and those in the sward were -0.66±1.47℃, 7.1±4.3% and 0.85±7.41ppm, respectively. 3) The results mentioned above indicate that the chamber method will be appropriate for measurement of photosynthsis in forage plant population or a sward and that the value measured by the chamber method will be reliable, if the conditions of temperature, relative humidity and CO_2 concentration inside the assimilation chamber were maintained similar to the sward conditions.

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1. Calculating the variation of dry matter weight in orchardgrass population after cutting by eqs.(4) and (8), we compared the calculated values with observed values. dw=α(1-e^<-at>)・W・dt…(4)[numerical formula] α and a are constants which indicate the variation of photosynthesis in plant community after cutting. n and m are constants which indicate the variation of respiration rate of plant after cutting. r is a constant which indicates the mean respiration rate of plant. W_0 is a constant which indicates the dry matter weight at cutting. 2. The values which were calculated by eqs.(4) and (8) approximately agreed with the observed values. The adaptation of eq, (4) was especially good. But it was considered that the area of application of eq.(8) would be broader than that of eq.(4) in the case of estimating the amount of dry matter production and analysing the dry matter production because the decision of constants and calculation were easy in eq.(8) 3. We examined the method of decision of each constant, which was necessary in the case of calculating the amount of dry matter production and analysing the dry matter production by eq.(8) under many caltivating conditions.

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To improve the oversowing in grassland establishment that is thought to fit for difficult sites because of gravels, slopet, trees, labour shortages etc., the author studied the introduction of forage species with some coating materials and abhesives and compared germination of the pelleted seeds of various methods. Specially-made rotary type coating machine was also described. The results obtained are as follows: 1. Lime, infusorial earth, peat moss powder and bentonite were compared as coating material with 3% solution of methylcellulose as adhesive with seeds of hairy vetch and it was found that most of the materials except infusorial earth were excellent and gave good germination. Solutions of methyl cellulose 3%, gum arabic 13%, polyvinylalcohol 3%, Doharon, soil stabilizing agent, 5%, Bond 30%, algin 0.75% were compared as adhesives with infusorial soil as coating meterial. The combination of methylcellulose and gum arabic gave best result. Bond was also available for coating and ease of obtaining and there was no depression in germination of the pelleted seeds made of the industrial adhesive. 2. The mixture of coating materials with the rate of peat moss 30, lime 50, bentonite 9 with bond 30% solution was thought to be satisfactory and the possibility of mixing fertilizers into the coating materials with crimson clover seeds was studied. 1) Mixing ammonium sulphate as coating material into the mixture was injurious for seed germination even at 5% in weight. 2) Superphosphate did not reduce germination at 5% and mixing fused phosphate was safe up to 20% but it is not good for pelleting from its glassy characteristics. 3) Muriate of potash reduced germination when mixed at 5% into the mixture. 4) Germination was safe when the compound fertilizer (15-15-15) was added to the mixture up to 5%. 5) Dried fowldung can be mixed into the mixture to 5% to maintain germination and barnyard manure can be mixed to 25% which is a good material for pelleting. 3. Insecticides such as heptachlor and S-seven can be used as coating material up to 100% and are good for coating. Mercuric fungicide can be mixed up to 20% but 1% is enough to protect seeds from fungal attack. 4. 10 cool-temperate grasses, 10 legumes and 8 warm-temperate grasses were compared for germination after treated with coating materials only and adding 5% of compound fertilizer (15-15-15) into the mixture and discussions were made from the date. 1) Cool-temperate grasses Coating promoted germination of smooth bromegrass, reed canarygrass and timothy but it did not give good results to orchardgrass, tall fescue and Kentucky bluegrass. Adding fertilizer did not reduce germination of smooth bromegrass, timothy and Italian ryegrass while seeds of orchardgrass, tall fescue, perennial ryegrass and Kentucky bluegrass were susceptible to added fertilizer. 2) Cool-temperate legumes Coating and adding fertilizer to the mixture promoted germination of hairy vetch, alfalfa, Ladino white clover and lupin seed could not germinate with the coating. Coating seemed to fit for legume seeds rather than for grass seeds. 3) Warm-temperate grasses Germination of sorgo, Rhodesgrass, bermudagrass was promoted by the seed coating but there was not the case with pearl millet. Adding fertilizer into the mixture was effective for the germination of Rhodesgrass and bermudagrass.

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There are some disadvantages in pelleting seeds with wet coating as there remains fears that pelleted seeds might germinate or reduce germination during storage and they are still inconvenient for mechanical seeding as their sizes and shapes vary widely according to species even if they are larger and heavier by pelleting. To avoid the moisture additives in the pellets, the author tried to apply direct compression method with the use of microcrystalline cellulose to coat the seeds mixed in tablets. Tablets were 9mm in diameter and 3mm in thickness and the weight being 200-300mg. The possibility of granulation of the tablets and its applicability for surface sowing were examined. The results are as follows: 1. Additive of twenty times in weight of seed was thought to be suitable in making tablets in case of Italian ryegrass seeds as the number of seeds in a tablet was about five. 2. The coating and disintegrations of tablets were satisfactory for germinating crimson clover seeds when the mixture of microcrystalline cellulose to peat moss powder was 50-80% to 50-20% in weight and there was not a remarkable decrease in germination because of directs compression. 3. Although the hardness of tablets were promoted by mixing granulations of peat moss, this method was not attractive as it reduced germination of crimson clover seeds. 4. Mixing concentrated superphosphate in the tablets reduced germination of Italian ryegrass, while calcium magnesite did not. Both fertilizers reduced germination of clover seeds. Mixing compound fertilizer (14-14-14) was limited to less than 1% in weight as it reduced germination severely, but adding algin (1%) recovered it. 5. Applicability of direct compression to the seeds of forage species was studied with seven cool-temperate grasses, seven cool-temperate legumes and four warm temperate grasses. The method promoted germination of alsike clover and Bermudagrass seeds only and there was some future for small seeded species such as Ladino white clover, birdsfoot trefoil and Kentucky bluegrass and it was doubtful whether the method could promote germination of orchard-grass, timothy and red clover seeds.

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Under rotational grazing system, dairy heifers in treatment A were moved at 9a.m. to a next fresh paddock at intervals of from 3 to 5 days on each rotation and those in treatment B were moved at 5p.m. Four heifers were involved in each treatment and different 6 paddocks were used for each rotational system. Experiment was conducted from mid-May to mid-August in 1970 and 1971. Observations covering from 4 to 6 days were carried out 2 times in 1970 and 3 times in 1971. A few supplemental observations were made when heifers in both treatmments had been placed on the same paddock after the experimental period. Location of each animal was also noted during both experimental and supplemental periods. 1) In all observation periods heifers in treatment B spent more grazing time than the time spent by heifers in treatment A. In treatment B, heifers showed a distinct grazing activity in the morning and evening which seemed to be natural periodicity of cattle behavior. But in treatment A three periods of grazing activity were noted and the first peak occurred in the early morning got much smaller than that in treatment B. In treatment A, on the other hand, there was a large peak from 9a.m. to 12a.m. It can be considered that stimulus by fresh grass has a stronger effect on appetite of heifer than natural periodicity of grazing activity and heifer learns the rhythm of rotation and the moving time. Heifers in treatment A were forced to graze the new fresh grass in the daytime, so they got away from their natural periodicity of grazing habit and had shorter grazing time than in treatment B. These effects continued to supplemental period in which heifers in both treatments were placed on the same paddock and grazed same way. 2) Heifers were 8-9 months old and had been raised at different farms one another till the beginning of the experiment. They soon behaved as a group in each treatment and simultaneity of their grazing activity was very high. However, when heifers in two treatments had been placed on the same poddock after being grazed on each paddock for about three months, they did not go about together and behaved as a quite different group within a small paddock as 10 ares. This phenomenon continued over half month, but we did not make certain about further period.

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