In this study were examined the changes in carbohydrates, sucrose hydrolyzing activity (SHA) (opt. pH 5.0) and fructosan hydrolyzing activity (FHA) (opt. pH 5.5) in the soluble fraction in the haplocorm of timothy plant (Phleum pratense, L.) during the regrowth after cutting. The mean fresh weight of a haplocorm was almost constant during the first 4 days and then decreased to about 5/6 of initial level. The total sugar in a haplocorm also decreased up to 20% in 20 days after cutting. Protein concentration in a haplocorm increased during the first 12 days, followed by drastic decrease. Fructosan content in the haplocorm declined gradually at the early stage and then decreased markedly during 8 to 12 days. SHA was maximum at 4 and 12 days, while FHA only at 12 day.

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Studies were undertaken to determine the mechanisms by which anthracnose resistance contributes to improved performance of alfalfa. Four alfalfa strains bred for high anthracnose resistance and the four varieties from which they were derived were used as bioindicators to determine the effects of anthracnose. Scores for anthracnose damage and fall frost damage at two locations in Maryland indicated a strong consistent relationship between anthracnose resistance and frost tolerance. This was attributed to the effect of anthracnose disease stress increasing the sensitivity of diseased plants to frost damage. At one location in Maryland, anthracnose susceptibility resulted in severe foliar discoloration. Data from three locations indicated that the resistant strains had a greater number of plants and tillers per unit of plot area. A negative effect of anthracnose on the number of tillers per plant could not be detected in either the fall or spring. Plant height tended to be taller for the resistant strains. It was concluded that the superiority of the resistant strains, after development of anthracnose epiphytotics, was expressed in a greater number of surviving plants and tillers per unit of plot area, taller plant growth, and increased frost tolerance.

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An experiment was conducted to investigate the use of preceding oats or Italian ryegrass with undersown Setaria (Setaria anceps cv. Kazungula) herbage. It consisted of five combinations of the crops, that was three pure plots of Setaria (S-pure), oats (O-pure), and Italian rygrass (I-pure), and two undersowing plots of Setaria with oats (O-S) and that with Italian ryegrass (I-S). Sowings and cuttings were practiced as shown in Fig.1. Results were summarized as follows, 1) Germination percentage of Setaria was reduced, but not significantly, when accompanied with the preceding crops. About two months later, Setaria establishment percentage among aftermath of the accompanied crop showed significant reduction owing to the low light intensity (Table 1). 2) Earlier dry matter yield of preceding crops was added in undersowing plots, but the differences in the total yield among those and S-pure were not significant as shown in Fig.2. Higher Setaria component was resulted in O-S than in I-S plot. 3) At the third cutting (2 Aug.), when Setaria growth alternated with the aftermath of preceding crops, both undersowing plots yielded only about a quarter of S-pure, reflecting heavy competition for light. 4) Growth analysis of Setaria plant at the alternation period was shown in Fig.3. At the 25th day from sowing, Setaria plant weight under oats and Italian ryegrass was retarded to 1/9 and 1/90 respectively, comparing to that of the pure plot ; this shows delay of about 11 and 33 days growth respectively. Relative growth rate per day of Setaria showed the highest value of 0.078 in case of with oats, which supposed to be better combination than with Italian ryegrass.

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[in Japanese]

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Using Iδ index (Morisita), the dispersive structures of the plant individuals in population of several pastures were examined. The results are summarized as follows: 1. At the beginning of establishment, the dispersive structures of the plant individuals population of pastures became contagious as the results of heterogeneities of seeding and germination. With growth of individuals, the death of slender plants occurred frequently in the places with high plant density. Therefore the dispersive structures changed from the contagious phase to the random by degrees. 2. The changes of dispersive structures were accelerated by hard competition under the high levels of fertilizer application and the few frequencies of cutting. 3. The mode of distribution on composition of species in pastures correlated with the degree of dominance. The dispersive structures of dominant species showed random and those of inferior species showed contagious. Further the examination was conducted to analyze the condition and trend of several pastures based on the dispersive structures.

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1. We have been studying the feeding system of roughage mainly by whole year utilization of silage in daily farm since 1961. As the results, we found that the feeding system demanded the technique for silage producton of good quality and stability. This experiment was conducted to find the mutual effects of several factors on silage quality about autumn seeded Italian ryegrass that was harvested within the year, April and June. The conducted factors were moisture content (controlled by wilting), storage temperature and storage period. 2. Chemical composition of ensiled materials ; The order of moisture content was April>June>within year, and all materials contained more than 80%. The order of water soluble carbohydrate content was within year>April>June, and there were sever difference among the time of harvesting. The order of crude protein content was the same as that of water soluble carbohydrate content, but all materials contained same as or more than 20%. In accordance with wilting, crude protein content was a little change but water soluble carbohydrate content was decreased apparently. 3. The mutual effects of each factor on silage quality were summerized as follow ; i. The mutual effect of moisture contents in ensiled materials and storage periods ; In unwilting silage, silage harvested within year didn't change to low quality as period progresses, but silages harvested April and June changed to low quality. The change of silage quality as period progresses was consistent with water soluble carbohydrate content in ensiled materials. The wilting inhibited VFA production but for lactic acid production is promoted or inhibited according to circumstances. ii. The mutual effect of moisture contents in ensiled materials and storage temperatures ; In unwilting silage, silage harvested within year didn't change to low quality as heightening temperature, but silage harvested April and June changed to low quality. All wilting silages didn't change to low quality either. iii. The mutral effect of storage temperatures and storage periods ; There was few mutual effect of these two factors. Silage quality had a tendency to show additional change in oder of high temperature or long period. It is seemed that within the range of this experiment (from 15 to 30 degree C) heightening storage period, in other word, storage temperature have the effect of the fermentation rate rather than the silage quality. 4. Comparison with silage quality among times of harvesting ; In unwilting silage, water soluble carbohydrate content in ensiled materials was consistent with silage quality, and the disparity in silage quality increased with lenghtening period. In wilting silage, about 60% moisture content, all silages were good quality, but there were difference in production of organic acid among times of harvesting, so that it was seemed that the type of fermentation was different in wilting silage too.

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This paper is the first of series in which the results of studies on the methods of evaluation of forage quality by hamsters will be presented. One of the initial problems was to clarify the hamster's growth response to forages. We tried a few experiments with respect to the growth response in weaned hamsters to hay and fresh legumes. When the level of hay in the diet was below about 50% hamsters gained weight ; and existed on a 75% hay diet. Hamsters survived and gained weight when fed on only legumes, without being supplemented with water and other nutrients. Growth response of hamsters to fresh alfalfa was far better than to fresh red clover. Dry matter intake of legumes by hamsters was about 10% of body weight. A considerable amount of dry matter, energy, cell wall constituents and crude protein of fresh legume were digested by hamsters.

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Digestion trials were conducted with hamsters produced in our laboratory and voles trapped in pasture to compare their digestive ability in fresh orchardgrass harvested at two different stages of maturity and red clover harvested at heading stage. All forages were minced by a meat chopper and mixed with basal diet which composed of casein, sucrose, soybean oil and mineral-vitamin mix., at levels of 30% of orchardgrass and 50% of red clover. These animals were placed in wire metabolism cages and their feces and urine were collected daily for a five days, and digestibility and nitrogen balance were determined. Relative intakes were greater in hamsters than voles. When intake was expressed on the basis of metabolic body size (W/g^<0.75>), there was no difference between hamsters and voles. Two species consumed greater amount of red clover than orchardgrass harvested at two different stages. Voles had a greater gain when fed with red clover than with orchardgrass, whereas gains of hamsters were similar for all forages. Digestibility of dry matter were similar for hamsters and voles, and both species digested the dry matter of red clover better than that of orchardgrass. Digestibility of cell wall constituents did not show any difference for voles and hamsters fed orchardgrass, harvested at early bloom stage. However this was greater for voles fed orchardgrass harvested at full bloom stage, but lower for voles fed red clover compared with hamsters. Voles digested more nitrogen than hamsters for the test feeds except orchardgrass harvested at early bloom stage. On the contrary, retained nitrogen of hamsters was greater than that of voles. It was suggested from these results that forage digestive ability of hamsters was not at all inferior to that of voles.

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