Browsing by Subject "Zucker"

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Effects of seed coating on germination and early seedling growth in cereals
(2014) Gorim, Linda Yuya; Asch, Folkard
Grain cereals such as barley, rye, wheat or sorghum, constitute a major share in human diet worldwide. Climate change threatens cereal production systems due to emerging unreliable rainfall patterns and thus, renders crop production vulnerable to early season failure of crop establishment. Breeding drought tolerant genotypes is a long and complicated process, thus not suited to respond to environmental changes quickly but rather to address the problem in a longer time frame. Seed coats increasing water availability to the seed and enhancing early vigor of the seedling may be a better short term solution. Seed coats containing hydro-absorbers such as Stockosorb® or Geohumus® can improve water availability and in combination with other substances for example humic acids or plant fortifiers such as Biplantol® may improve early vigor. However, very low germination rates have been observed in seeds coated in this way resulting in slow adoption of seed coating technology in agriculture. The present study analyzed the effects of seed coating on germination, which seed coat composition can enhance germination rate and early vigor and why, the effects of seed coat on germination and seed physiology, and which influence seed coats containing different kinds of hydro-absorbers have on the drought resistance of seed during germination. Studies were conducted on barley, rye, and wheat seeds. In these species the mode of action of differently composed seed coats and the effects of differences in seed coat strength were studied whereas the studies on drought resistance were performed with sorghum seeds. The following results were obtained and submitted for international publication: 1) Seed coating in general reduced germination rates as compared to uncoated seeds. Seed coating thickness was the determining factor. With a share of the seed coat of 75% of the total grain (seed + seed coat) germination was very little affected by coating. However, smaller seed coat shares and particularly shares smaller than 50% of the total grain severely reduced germination rate. This effect was especially pronounced in wheat. 2) With seed coat shares larger than 75% and the coats dotted with different substances generally resulted in high germination rates. However, strong genotypic effects were observed in responses of seed physiology and dry matter partitioning to the different substances included in the coat, with barley generally responding positively, rye intermediate and in wheat generally the weakest effects were observed. Across genotypes Biplantol included in the coat mainly promoted shoot growth, humic acid increased root growth and hydro-absorbers mainly the rate of germination and early vigour. Due to those results only seed coated with hydro-absorber containing coat and with coat not smaller than 75% were used for all following studies. 3) Seedlings growing from coated seeds with coat shares > 75% showed accelerated early seedling growth with strongly reduced respiratory losses during the mobilization of endosperm reserves, combined with significantly increased mobilisation efficiency in all three cereals. Analyses showed that the sucrose metabolism and thus the availability of glucose as energy provider for growth differed strongly between coated and uncoated seeds as well as among the cereal species. Embryos from coated seed (particularly in barley and wheat) seemed to grow better with significantly less glucose indicating a chance in the enzymatic cleavage of sucrose that could only be due to the higher energy efficiency of the enzyme sucrose synthase. 4) Studies during germination in sensu stricto (the first 48h hours after soaking) showed that in the embryos of coated seeds conditions were hypoxic with oxygen concentrations of less than 5% of atmospheric oxygen as compared to 60-80% oxygen of atmosphere in embryos of uncoated seeds. From this it was deduced that the lower respiratory losses during germination of coated seeds are due to a switch in sugar metabolism from invertase based cleavage of sucrose to sucrose synthase based cleavage of sucrose which is the less energy demanding pathway in the near absence of oxygen. 5) A last study on drought resistance of coated seed whose coats comprised two different hydro-absorbers (Stockosorb or Geohumus) showed that the drought responses of coated seed differed little form uncoated seeds. However, seedling growth under both drought and fully watered conditions was affected by the type of hydro-absorber in the coat. Whereas Stockosorb promoted rather root growth,Geohumus enhanced shoot growth. In conclusion, it can be stated that seed coats investigated in this study in general promoted germination rate and success in cereals if the seed coat has the appropriate strength i.e. coat shares not below 75% of total grain. Additives such as Biplantol or humic acid promote vigour and influence dry matter partitioning in favour of specific organs which could be employed as management options during germination. It was shown that seed coats influence the germination and seedling metabolism und induce hypoxic conditions in embryonic tissue which shift the sugar metabolism to a more energy efficient pathway. Oxygen dynamics in the different seed tissues require further studies and need to be better understood in order to employ the positive effects of seed coating in a targeted and species-specific approach to improve and enhance crop establishment particularly in drought prone cereal production systems. Another future pathway could be including nutrients in the coat that promote early seedling growth and for systems threatened by early drought spells or unreliable rainfall a seed coat that would conduct water to the seed only after soil moisture has surpassed a given threshold and thus induces germination only when water availability is optimal.
The Competitiveness of the Sugar Industry in Thailand
(2007) Arjchariyaartong, Wuttipong; Zeddies, Jürgen
Thailand is now firmly established as one of the world?s leading sugar exporting countries. During 1995/96 to 2005/06, sugar exports ranged between 2.3 and 5.1 million tons and averaged 3.80 million tons per year. For this reason, sugar cane production is one of the major economic sectors in Thailand. There are several activities involved in the production process such as sugarcane growing, sugar milling, credit banking, exportation, etc. The sugar production activities provide significant full time and temporary employment in sugar factories, sugar transformation, transportation and exports. Therefore, the study of sugar cane and sugar industry?s competitiveness is important, especially with the increasing liberalisation of the world market. Based on the above considerations, this thesis has key objectives as follows: 1. To study the structure of sugarcane and sugar production in Thailand. 2. To analyse costs and returns of sugarcane and sugar production in Thailand. 3. To examine the competitiveness of the sugar industry and identify indicators of competitiveness. 4. To describe strategies of sugarcane growers and sugar factories for improving competitiveness. The methodology applied for the farm sampling is based on the concept of typical farm approach. Farm types are determined by sugarcane experts taking into consideration: location of farm, farm size, sugarcane area and share of rain-fed and irrigated area. The first category of farms was chosen to represent the size that is close to the statistical average. The other types defined represent larger farms to allow the exploration of potentials for economies of size in the region. Management levels on the typical farms are above average. The sugar factories were categorized by region, industry group and crushing capacity. Firstly, the structure of sugar cane production in Thailand can be described as follows. Sugar cane is grown all over the country. The total cane area amounted to 6.34 million rai in 2004/05. The most important regions of sugar cane production are the Northeastern, the Central and the Northern region. The total cane production amounted to 47.82 million tons in 2004/05 with an average yield of 7.54 tons/rai. Secondly, the structure of the sugar industry in Thailand can be described as follows. Within the total number of 46 sugar factories, there are 4 large factories with a crushing capacity of more than 24,000 tons of cane crushed per day, 16 medium size factories (12,000-24,000 tons/day), and 26 small size factories (< 12,000 tons/day). Thirdly, the sugar market in Thailand can be described as follows. The total sugar production amounted to 7 million tons in 2003/04. With a share of domestic consumption of 27.8%, only around 2 million tons of sugar is used for domestic consumption. The rest of around 5 million tons of sugar is exported to the world market, mostly to Asia. The wholesale prices for the domestic market are annually fixed by the government to around 12 Baht/kg in the average. Fourthly, the results of sugarcane farms can be concluded as follows. The analysis of sugarcane costs of production has shown that the total production costs of sugarcane farms for the first ratoon are highest and then decrease in the second and third ratoon. The farms in the Central region have higher average production costs (4,245 Baht/rai) than the cane growers in the Northeast (4,130 Baht/rai) and in the North (3,725 Baht/rai). Low labor costs, especially harvesting costs of around 1,142 Baht per rai, are the predominant reason for the lower cost structure of the farms in the Northeastern region. Fifthly, the results of the sugar factory analysis can be concluded as follows. The five investigated factories are one large factory with a crushing capacity of more than 23,000 tons of cane per day, and four small factories with a cane crushing capacity of less than 12,000 tons/day. Although most of the cane suppliers are small size farmers, the majority of cane comes from medium and large farms. The sugar sales are depending on the type of sugar and the market channel and range from 14 Baht/kg to 18 Baht/kg. The average distance of sugarcane transport is around 53.33 km for sugarcane which is purchased from sugarcane farmers. The closer the sugarcane fields to the factory are the higher is the competitiveness of the sugar factory. The productivity analysis of the sugar industry shows that factory C possesses an advantage with respect to the quantities of total sugar production per rai in production year 2002/03 and 2003/04. The result of ranking the sugar factories according to their competitiveness shows that factory C has an advantage in the total quantity of sugar production per rai. Factory E had the highest advantage in the extraction rate of sugar per ton of sugar cane and gained the highest profit of sugar production. However, factory B has the highest ability to produce sugar with the lowest costs per kg and factory D was the leader in reducing costs of sugar production in Baht per rai. In the summary, the score over all indicators of competitiveness shows that factory E has the highest score. Therefore, factory E has been ranked to be the most competitive factory, followed by factory B, factory D, factory A, and factory C respectively. Finally, this study provides suggestions and policy recommendations for sugarcane farms and sugar factories in four areas. First, sugarcane productivity per rai is still low in Thailand, therefore research and development is necessary in the field of optimization of the production process and breeding of new sugarcane varieties. Second, enough water and access to irrigation system is very important for sugarcane planting, so the government should help to provide these facilities for the farmers. Third, the sugar industry should differentiate their sugar products in order to increase the value added of sugar production. This will help sugar factories in case of encountering the situation of low prices of sugar. Fourth, due to increasing energy costs, sugar factories should get support in acquiring alternative energies and reducing other costs of production by research and development.
Ultraschallbasierte simultane Konzentrationsbestimmung der Komponenten Zucker und Ethanol in wässrigen Fermentationsfluiden
(2014) Schöck, Thomas; Hitzmann, Bernd
At alcoholic fermentation processes in aqueous solutions there are converted various sugars (mono-, di- and polysaccharides) into ethanol and carbon dioxide by diverse intermediate steps. In the industrial production, ultrasound based methods for the analysis of the composition of the fermentation fluid are advantageous due to their robustness, price cheapness and the possibility for the accomplishment of on line measurements. Within the scope of the present work there are presented several methods for the simultaneous determination of the sugar and ethanol content in the fermentation fluid based on the analysis of ultrasound parameters, also at the presence of dissolved carbon dioxide gas, and compared with respect to the accuracy of their predictive values. Initially there is investigated the behavior of the parameters sound velocity and adiabatic compressibility in standardized aqueous fluids in dependency of the concentration of the components sugar (2 -16 mass percent) and ethanol (1- 6 mass percent), the CO2 partial pressure (0 – 3,013E+05 Pa) and the temperature (2 – 30° C). Thereby the disaccharide saccharose acts as a model substance for the sugar fraction. From the data field of the sound velocity two polynomial calibration models for the sugar / ethanol concentration are extracted with the methods of the multiple linear regression (MLR) and the partial least squares (PLS-) analysis. The minimal accessible standard deviation of the concentration values determined by the particular model from the reference values lies for the MLR method at 0,6 mass percent for the sugar and 0,2 mass percent for the ethanol fraction. The PLS-analysis yields a standard deviation for the sugar and ethanol values of 0,36 and 0,13 mass percent respectively (fluids without a CO2 fraction), as well as 0,5 / 0,17 mass percent (fluids including a CO2 fraction). A further analytic method uses a linearized model of the adiabatic compressibility and the density for the sugar / ethanol determination. The analysis of two physical parameters at this method yields a significant increase of the model quality. For fluids without a CO2 fraction there is reached a minimal standard deviation of 0,06 mass percent for the sugar and 0,07 mass percent for the ethanol concentration. For CO2 containing fluids the corresponding values results to 0,06 / 0,13 mass percent.