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The role of the labile methyl groups of betaine in the transmethylation reactions in the barley plants was investigated using carbon-14 methyl labelled betaine. The N-methyl groups of N-methyl tyramine, hordenine and choline were found to arise from betaine. Betaine was also administered to castor bean seedlings and the alka­loid ricinine isolated. It was found that its N- and 0-mthyl groups did not arise from betaine methyl. The origin of the methylenedioxy and N-methyl groups of the alkaloid protopine was also investigated by the tracer technique. Carbon-14 methyl labelled L-methionine, carbon-14 labelled choline and carbon-14 labelled sodium formate were fed to Dicentra species and the extent and position of labelling of the protopine molecule determined by degradation / Thesis / Master of Science (MS)

Turgid, water stressed, and recovered leaf tissue from barley (var. Barbless) and tomato (var. VF 36 ) were analyzed for total chlorophyll, soluble protein, RuDPCase concentration, and RuDPCase specific activity. Water stress caused a reduction in all physiological characteristics measured. The reduction in concentration of chlorophyll, soluble protein and RuDPCase specific activity in both plants paralleled decreased water potential during first wilt. Changes associated with barley plants as compared to tomato first wilt plants were more pronounced. Barley lost 25% more water than tomato. Repeated wilt cycles increased sensitivity of tomato plants to reduction in chlorophyll content, soluble protein concentration, and RuDPCase specific activity. After a period of rewatering (24 hours) levels of chlorophyll content, soluble protein concentration, and RuDPCase specific activity returned to approximately control levels. Specific activity of RuDPCase is reduced even under low levels of water stress. Concentration of all soluble proteins are not equally reduced as a result of water stress. Total soluble protein was reduced 33% and RuDPCase 11% of control level.

Hordeum jubatum L., Hordeum brachyantherum nevski, and Hordeum jubatum var. caespitosum (Scribn.) Hitchc. Plants from sites in Utah and Idaho were grown and examined in order to determine whether or not hybridization with subsequent introgression occurs among the species and if so whether there is a difference in the relative amount of gene flow between the parent species H. jubatum and H. brachyantherum in different environments. Hybridizations and morphological analyses were made using standard procedures. Biochemical analyses were made by comparing paper chromatograms of leaf extracts of plant specimens. The results indicate that in Utah populations sampled, hybridization with subsequent introgression is present. Furthermore, introgression has apparently resuted in the formation of stable introgressants in Utah. Idaho populations ampled, from a high mountain area, appeared to be stable and devoid of hybridization and introgression. Possible exlanations concerning the apparent lack of hybridization and introgression are given.

<p> Barley coleoptiles were observed to be remarkably variable in height at 72 hr of germination. The objective or the study presented here was to analyze this variation in growth among coleoptiles and to attempt to determine its cause. The first step in this analysis of the variation was to determine the growth patterns of 900 individual coleoptiles by measuring their heights periodically during their growth period. In determining the cause for the variation, genetic, environmental, hormonal, metabolic and cytoplasmic factors were considered. For example, since gibberellin and kinetin have been implicated in the control of cell division and cell elongation these growth factors were supplied exogenously to germinating seedlings in an attempt to stimulate uniform growth of all coleoptiles. In similar studies, the effect or physical conditions and co2 on coleoptile growth was determined variation in growth is shown by any one of a number of parameters. Proteins, however, because they are closer to gene activity than the others are a better indicator of whether the variation in growth is caused at a fundamental level. Variations similar to those in coleoptile height were found in the amino acid analysis of different types of coleoptiles. Experiments were also done to determine if a genetic component was responsible for the variation in coleoptile growth. There was no correlation between germination pattern of a seedling and that of its progeny; therefore, the variation in growth was attributed to differences in cytoplasmic constituents of individual coleoptiles. </p> / Thesis / Doctor of Philosophy (PhD)

The role of the labile methyl groups of betaine in the transmethylation reactions in the barley plants was investigated using carbon-14 methyl labelled betaine. The N-methyl groups of N-methyl tyramine, hordenine and choline were found to arise from betaine. Betaine was also administered to castor bean seedlings and the alkaloid ricinine Isolated. It was found that Its N- and 0- methyl groups did not arise from betaine methyl. The origin of the methylenedioxy and N-methyl groups of the alkaloid protopine was also investigated by the tracer technique. Carbon-14 methyl labelled L- methionine, carbon-14 methyl labelled choline and carbon- 14 labelled sodium formate were fed to Dicentra species and the extent and position of labelling of the protopine molecule determined by degradation / Thesis / Master of Science (MS)

京都大学 / 新制・課程博士 / 博士(地域研究) / 甲第24021号 / 地博第300号 / 新制||地||117(附属図書館) / 京都大学大学院アジア・アフリカ地域研究研究科アフリカ地域研究専攻 / (主査)教授 重田 眞義, 教授 大山 修一, 准教授 金子 守恵, 教授 高橋 基樹 / 学位規則第4条第1項該当 / Doctor of Area Studies / Kyoto University / DGAM

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The overall objective of this study was to evaluate the effects of feeding hulless barley and supplementing a xylanase enzyme on production performance and nutrient utilization of lactating dairy cows. In study 1, we evaluated production performance, milk fatty acid composition, and nutrient digestibility in high-producing dairy cows consuming diets containing corn and hulless barley in different proportions as the grain source. We hypothesized that a plausible reduction in production performance would be explained by an altered rumen function, which would be reflected in a reduction of the proportion of de novo fatty acids in milk fat. The inclusion of hulless barley grain as the energy source in diets for lactating dairy cows resulted in similar production performance and nutrient utilization as corn grain. We concluded that hulless barley is as good as corn grain as an energy source and increasing NDF concentration in hulless barley-based diet is not necessary. In study 2, we evaluated production performance, nutrient digestibility, and milk fatty acid composition of high-producing dairy cows consuming diets containing hulled or hulless barley as the grain source. We hypothesized that rumen function is altered when cows are fed low-forage diets containing barley grains, and this altered rumen function would be reflected in lower production performance and a reduction of fatty acids synthesis in the mammary gland. Contrary to our expectations, feeding hulled barley or hulless barely based diets with different forage to concentrate ratios to lactating dairy cows resulted in similar production performance and nutrient utilization. We concluded that both hulled or hulless barley grains are good energy sources for sustaining high milk production and there is no need to increase NDF concentration in diet when using barley grain as the grain source. In study 3, we evaluated the effects of supplementing a xylanase enzyme on production performance and nutrient digestibility of lactating dairy cows fed diets containing corn or sorghum silage as the forage source. We hypothesized that supplementing a xylanase enzyme product in diets containing corn or sorghum silage increases NDF digestibility, and production performance of lactating dairy cows would also be improved due to enhanced fiber digestion. Supplementation of xylanase for 19 d did not affect cow performance and nutrient utilization. Supplementation of xylanase may require a longer period of time to show any response in production performance and nutrient digestibility. We concluded that supplementing xylanase to cows fed corn or sorghum silage-based diets did not improve fiber digestion. But for feeding hulled or hulless barley grains to lactating dairy cows, increased NDF concentration in diets is not necessary and hulless barley is good as corn grain for feeding lactating dairy cows as the grain source. / Ph. D. / The overall objective of this study was to evaluate the effects of feeding hulless barley and supplementing a xylanase enzyme on production performance and nutrient utilization of lactating dairy cows. Barley starch is fermented faster than corn starch and can possibly reduce ruminal pH. Reduced ruminal pH can compromise cow production performance and cause some health problems. In study 1, we evaluated production performance, milk fatty acid composition, and nutrient digestibility in high-producing dairy cows consuming diets containing corn or hulless barley as the grain source. We hypothesized that a plausible reduction in production performance and milk fat percentage would be reduced by feeding hulless barley as the grain source in the diet. According to our results, the inclusion of hulless barley grain as the energy source in diets for lactating dairy cows resulted in similar production performance and nutrient utilization as corn grain. We concluded that hulless barley is as good as corn grain as an energy source and increasing fiber concentration in hulless barley-based diet is not necessary. In study 2, we evaluated production performance, nutrient digestibility, and milk fatty acid composition of high-producing dairy cows consuming diets containing hulled or hulless barley as the grain source. We hypothesized that rumen function is altered when cows are fed low-forage diets containing barley grains, and this altered rumen function would be reflected in lower production performance and a reduction of milk fat percentage. Contrary to our expectations, we did not observe any differences in cow production performance among all treatments. We concluded that both hulled or hulless barley grains are good energy sources for sustaining high milk production and there is no need to increase fiber concentration in diet when using barley grain as the grain source. In study 3, we evaluated the effects of supplementing a xylanase enzyme on production performance and nutrient digestibility of lactating dairy cows fed diets containing corn or sorghum silage as the forage source. We hypothesized that supplementing a xylanase enzyme product in diets containing corn or sorghum silage increases fiber digestibility, and production performance of lactating dairy cows would also be improved due to enhanced fiber digestion. Supplementation of xylanase for 19 d did not affect cow production performance and nutrient digestion. The effects of supplementation xylanase may require a longer period time to detect. We concluded that supplementing xylanase to cows fed corn or sorghum silage-based diets did not improve fiber digestion. For feeding hulled or hulless barley grains to lactating dairy cows, increased fiber concentration in diets is not necessary and hulless barley is good as corn grain for feeding lactating dairy cows as the grain source.

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