In 2005 biogas and methane increased from lower values at the first harvest to a maximum at the third from where it decreased at the fourth in Giessen. The same cultivars grown in Gross-Gerau showed instead decreasing biogas and methane with advancing maturity. KXA5233 (S 260) could be observed to outperformed Gavott (S 250) in both Giessen and Gross-Gerau.
In 2006 biogas and methane were observed to decrease with advancing maturity in Giessen but to increase in Gross Gerau. The late cultivars (Fiacre S 350 and Baxter S 300) again outperformed the earlier ones in Gross-Gerau. However by comparing the cultivars in Giessen to those in Gross-Gerau, both biogas and methane productivity were found to be higher in Giessen than in Gross-Gerau and the late cultivars in Gross-Gerau did not outperformed all the middle early cultivars in Giessen. While the impact of cultivar on maize chemical composition, biogas and methane productivity seemed to be clear, the impacts of harvest time all the three factors (chemical composition, biogas and methane) proved very obscured. In the same way the impact of maize chemical composition on biogas or methane productivity could not also be clearly defined.
The hypothesis at the beginning of the thesis that dry matter, biogas and methane yields are functions of genotype, maturity at harvest, and location can be said to have hold true according to the observations made with the experiments. However the hypothesis by which delaying harvest was expected to increase dry matter yield biogas and methane yields could not be established. That higher specific biogas volumes also should yield higher specific methane volumes was proven true in all the locations and experimental years.
Summary
Biogas is an alternative source of methane and can be used as a renewable substitute for natural petroleum gas. The major challenges faced by producers of biogas from energy crops like maize are the ability to choose appropriate genotypes and maturity stage to harvest for optimum dry matter, biogas and methane yields.
In 2004, 2005 and 2006, a germplasm consisting of four maize inbreed lines and nine cultivars (hybrids) were selectively planted in combination with 4 harvest times at the research stations Giessen and Gross-Gerau. In the field experiments a randomised design in four blocks each with four replications was used. Each block with its four replications represented a harvest time. The cultivar Gavott (S 250) was used as a standard determining the first harvest time at the maturity stage milking ripeness. The second harvest time followed the first two weeks later, the third also followed the second two weeks later and the fourth followed the third also two weeks later. In all 6 experiments plant length, dry matter content and dry matter yield were measured.
During maize growth leaf area index (LAI) only in Giessen 2005 and 2006 were determined. At each of the four harvest times samples were taken and NIRS analysis to determine crude protein (CP), crude fibre (CF), neutral detergent fibre (NDF), acid detergent fibre (ADF), sugar, starch and enzymes soluble substances (ELOS) were executed. Biogas and methane productivity (measured in batch digester) were determined only in first, third and forth harvest time.
LAI showed significant cultivar harvest time interactions only in 2005. With the exception of Gavott the rest of the cultivars showed higher LAI in 2005 (LAI 4 – 5) compared to the drought affected experiments of 2006 (LAI 3 – 4). Late cultivars and inbreed lines were clearly taller than the early ones in Giessen as well as in Gross-Gerau. The impact of location was such that both the early and late cultivars were taller in Gross-Gerau than in Giessen. In most cases there was no correlation between maize length and LAI.
Statistical evaluation of data from all the experimental years and locations showed significant cultivar and harvest time interactions in dry matter yield as well as in all chemical compounds (CP, CF, ADF, NDF, sugar, starch, ELOS) measured in both stations Giessen and Gross-Gerau. Delaying harvest proved a way to increase dry matter yield and dry matter concentration but not optimum biogas yield and methane content. Late cultivars and new inbreed lines tended to produce more dry matter yield, biogas and methane than their early counterparts. Besides the impacts of cultivar and harvest time, dry matter yield, biogas and methane productivity also seemed to have been affected by location. Maize ELOS significantly increased with delaying harvest but there was no correlation between ELOS and biogas productivity.
It can be concluded, that dry matter content, dry matter yield, biogas yield and methane yield of maize are functions of genotype, maturity at harvest and location.
Key words: Maize, biogas, methane, harvest time, cultivars
Zusammenfassung
Biogas ist eine alternative Methanquelle und kann als erneuerbare Ressource statt natürlichem Erdgas genutzt werden. Die größten Zweifel beziehen sich auf die Produktion von Biogas, die auf dem Anbau von Energiepflanzen wie zum Beispiel Mais beruht. Denn dafür werden die Energiepflanzen durch veränderte Genotypen und andere Reifestadien auf hohen Trockenmasseertrag, Biogasgewinn und Methangehalt optimiert.
In den Jahren 2004, 2005 und 2006 wurde ein Feldversuch mit Mais sowohl auf der Versuchsstation Gießen als auch in Groß-Gerau angelegt. Der Versuch bestand aus vier Inzuchtlinien und neun Hybridsorten. Jede Sorte wurde auf vier unterschiedliche Erntezeitpunkte getestet. Die Versuchsvarianten wurden randomisiert in vier Blöcken mit jeweils vier Wiederholungen angeordnet. Jeder Block hatte einen anderen Erntezeitpunkt. An der Sorte „Gavott“ (S 250) wurde der Erntezeitpunkt anhand der Entwicklungsphase Milchreife als Standard festgelegt. Die anderen Erntetermine folgten jeweils im Abstand von zwei Wochen. Es wurden Pflanzenlänge, Trockenmassegehalt, und Trockenmasseertrag gemessen. In Gießen wurde der Blattflächenindex (engl. leaf area index: LAI) während des Wachstums 2005 und 2006 gemessen. Von allen vier Erntetermin-Varianten wurden Proben genommen und mit Hilfe von NIRS analysiert um Rohprotein, Rohfaser, in neutralen Detergenzien unlösliche Faser (engl. neutral detergent fibre: NDF), in sauren Detergenzien unlösliche Fasern (engl. acid detergent fibre: ADF), Zucker, Stärke und enzymlösliche Substanzen (engl. enzymes soluble substances: ELOS) zu erfassen.
Biogas und Methanproduktivität (gemessen in der Einzelproben-Biogasanlage) wurden für die Varianten des ersten, dritten und des vierten Erntetermins gemessen.
Der Blattflächenindex zeigt nur in 2005 signifikante Wechselwirkungen zwischen den Erntezeitpunkten. Mit Ausnahme der Sorte „Gavott“ zeigten alle Sorten einen höheren Blattflächenindex in 2005 (LAI 4–5) im Vergleich zu den Versuchen im verhältnismäßig trockenen Jahr 2006 (LAI 3-4). Späte Sorten und Inzuchtlinien wurden unabhängig vom Standort größer als frühe Sorten. Der Standortfaktor zeigte sich nur insofern, dass sowohl die frühen als auch die späten Sorten in Groß-Gerau eine höhere Pflanzenlänge als in Gießen erreicht haben. In den meisten Fällen bestand keine Korrelation zwischen Pflanzenlänge und LAI.
Die statistische Auswertung der Daten von allen Versuchsjahren und –Standorten ergab einen signifikanten Unterschied zwischen den Faktoren Sorte und Erntezeitpunkt sowohl in Bezug auf den Trockenmasseertrag als auch bezüglich der chemischen Komponenten (RP, RF, ADF, NDF, Zucker, Stärke, ELOS); in Gießen und ebenfalls in Groß-Gerau. Verzögerte Ernte erwies sich als eine Möglichkeit den Trockenmassegehalt und den Trockenmasseertrag zu steigern. Den optimalen Biogasertrag und Methangehalt erreicht man damit jedoch nicht. Späte Sorten und neue Inzuchtlinien tendieren zu einem erhöhten Trockenmasseertrag, Biogas- und Methangehalt im Vergleich zu ihren Vorgängern. Zusätzlich zum Einfluss der Sorte und des Erntezeitpunktes, des Trockenmasseertrages, der Biogas- und Methanpro-duktivität scheint es noch einen Effekt durch den Faktor Standort zu geben. Die enzymlösliche Substanz (ELOS) von Mais steigt signifikant mit einer verzögerten Ernte, aber es gibt keine Korrelation zwischen ELOS und der Biogasproduktivität.
Zusammenfassend kann man sagen, dass der Trockenmassegehalt, der Trockenmasseertrag, der Biogasertrag und Methanertrag von Mais vom Genotyp, Entwicklungsphase zur Ernte und dem Standort beeinflusst wird.
Schlüsselwörter: Mais, Biogas, Methan, Erntezeitpunt, Sorten
LITERATURE CITED
Afuakwa, J.J.; Crookston, R.K.Using the kernel milk line to visually monitor grain maturity in maize. Crop Science, Madison, v.24, n.4, p.687-691, 1984.
ALF Deggendorf , Sachgebiet 2.1 P und LfL, Versuchsberichtsheft "Integrierter Pflanzenbau" 2006 Amt für Landwirtschaft und Forsten Deggendorf.
Allen, M. S. and K.A. O'Neil. 1991. Effect of environment on fiber components and fiber digestibility of corn forage. Proc. XXI Biannual Rumen Function Conference, Chicago, IL
Amon, Th., V. Kryvosruchko, B. Amon, G. Moitzi, D. Lyson, E. Hackl, D.
Jeremic, W. Zollitsch, E. Pötsch, K. Mayer, J. PLanK, 2002:
Methanbildungsvermögen von Mais - Einfluss der Sorte, der Konservierung und des Erntezeitpunktes. Endbericht Oktober 2002. Im Auftrag von Pioneer Saaten GmbH Parndorf (Austria).
Amon, Th., V. Kryvosruchko, B. Amon, G. Moitzi, D. Lyson, E. Hackl, D.
Jeremic, W. Zollitsch, E. Pötsch, 2003: Optimierung der Biogaserzeugung aus den Energiepflanzen Mais und Kleegras. Endbericht Juli 2003. Im Auftrag des Bundes-ministeriums für Land- und Forstwirtschaft, Umwelt und Wasserwirtschaft. For-schungsprojekt Nr. 1249 GZ 24.002/59-IIA1/01.
Andrew L. Lewis, William J. Cox,* and Jerome H. Cherney 2004. Hybrid, Maturity, and Cutting Height Interactions on Corn Forage Yield and Quality. Published in Agron. J. 96:267–274 (2004).
Angelidaki, I. and Ahring, B. K. (1995) Isomerization of n- and i-butyrate in anaerobic,methanogenic systems. Antonie van Leeuwenhoek, 68, 285-291.
Angelidaki, I., L. Ellegaard and B. K. Ahring. 1999. "A comprehensive model of anaerobic bioconversion of complex substrates to biogas". Biotechnol. Bioeng., 63(5), 363-372 (1999).
Bal, M. A., J. G. Coors, and R. D. Shaver. 1997. Impact of the maturity of corn for use as silage in the diets of dairy cows on intake, digestion, and milk production. J.
Dairy Sci. 80:2497-2503.
Bal, M. A., J. G. Coors, and R. D. Shaver. 1997. Impact of the maturity of corn for use as silage in the diets of dairy cows on intake, digestion, and milk production. J.
Dairy Sci.. 80: 2497-2503.
Bal, M. A., R. D. Shaver, A. G. Jirovec, K. J. Shinners, and J. G. Coors. 2000b.
Crop processing and chop length of corn silage: effects on intake, digestion, and milk production by dairy cows. J. Dairy Sci. 83:1264-1373.
Bal, M. A., R. D. Shaver, H. Al-Jobeile, J. G. Coors, and J. G. Lauer. 2000a. Corn silage hybrid effects on intake, digestion, and milk production by dairy cows. J. Dairy Sci. 83:2849-2858.
Balch WE, Fox GE, Magrum LJ, Woese CR, Wolfe RS (1979). Methanogens: re-evaluation of a unique biological group. Microb Rev 43:260-296
Barrière Y., Traineau R., Emile J.C., Hébert Y. 1992. Variation and covariation of silage maize digestibility estimated from digestion trials with sheep, Euphytica 59 61–72.
Barriere, Y., J. C. Emile, R. Traineau, and Y. Hebert. 1995. Genetic variation in the feeding efficiency of maize genotypes evaluated from experiments with dairy cows.
Plant Breeding 114:144-148.
Batstone, D. J., Keller, J., Newell, R. B. and Newland, M. (2000) Modelling anaerobic degradation of complex wastewater. I: Model development. Bioresource Technology, 75, 67-74.
Beccari, M., Bonemazzi, F., Majone, M. and Riccardi, C. (1996) Interaction between acidogenesis and methanogenesis in the anaerobic treatment of olive oil mill effluents. Water Research 30(1), 183–189.
Beck, T., and F. Gross. 1964. (Causes of differences in the keeping properties of silage. Wirtschaftseignene Futter 10:298.
Bill Mahanna. 2005. Managing corn silage from seed to feed. In Proceedings of the 7th western dairy management conference .March 9-10, 2005. Reno, NV. 85
Boone, D. R. & Bryant, M. P. (1980). Propionate-degrading bacterium, Syntrophobacter wolinii sp. nov. gen. nov., from methanogenic ecosystems. Appl.
Environ Microbiol 40, 626-632
Boone, D. R. (1982). Terminal reactions in the anaerobic digestion of animal waste.
Appl Environ Microbiol 43, 57-64.
Boone, D. R., Johnson, R. L. & Liu, Y. (1989). Diffusion of the interspecies electron carriers H ion and formate in methanogenic ecosystems and its implications in the measurement of Km for H ion or formate uptake. Appl Environ Microbiol 55, 1735-1741.
Braun, R. 2005. Effect of silage preparation on methane yields from whole crop maize silages. In: Ahring, B. K. & Hartmann, H. (eds), Proc. 4th Int. 89 Symp. on Anaerobic Digestion of Solid Waste, Vol. 1: 109–115. BioCentrum-DTU, Copen-hagen.
Britz TJ, Trnovec W, Van Schalkwyk C and Roos P (1999) Enhanced Granulation in Upflow Anaerobic Sludge-Bed Digesters (UASB) by Process Induction and Microbial Stimulation. WRC Report No 667/1/99.
C. S. Ballard, E. D. Thomas, D. S. Tsang, P. Mandebvu, C. J. Sniffen, M. I.
Endres,† and M. P. Carter.2001. Effect of Corn Silage Hybrid on Dry Matter Yield, Nutrient Composition, In Vitro Digestion, Intake by Dairy Heifers, and Milk Production by Dairy Cows. J. Dairy Sci. 84:442–452.
Carter, P. M., J. G. Coors, D. J. Undersander, K. A. Albrecht, and R. D. Shaver.
1991. Corn hybrids for silage: An update. p. 141-164. In Proc. 46th Annu. Corn Sorghum Res. Conf., Chicago, IL. 46th Ann. Corn and Sorghum Res. Conf. America Seed Trade Association
Chynoweth, D. P., Turick, C. E., Owens, J. M., Jerger, D. E. & Peck, M. W. 1993.
Combs, D. K. 1998. Using NIR to evaluate forage quality. Pages 129-135 in Proc. of the 4-State Forage Feeding and Management Conference. University of Wisconsin Conrad, R. (1999). Contribution of hydrogen to methane production and control of hydrogen concentrations in methanogenic soils and sediments. FEMS Microbiology Ecology 28: 193-202.
Coors, J. G. 1996. Findings of the Wisconsin Corn Silage Consortium. p. 20-28.
Proc. of the 58th Cornell Nutrition Conference for Feed Manufacturers. October 22-24, 1997. Rochester, NY. Cornell University Press, Ithaca, NY.
Coors, J. G., K. A. Alblrecht, and E. J. Bures. 1997. Ear-fill effects on yield and quality of silage corn. Crop Sci. 37:243-247
Cox, W. J. Cherney .2001. Influence of brown midrib, leafy and transgenic hybrids on corn forage production. Agron. J. 93 : 790-796.
Cox, W.J., and D.J. Cherney. 2001. Influence of brown midrib, leafy and transgenic hybrids on corn forage production. Agron. J. 93:790–796. crop maize silages. In:
Ahring, B. K. & Hartmann, H. (eds), Proc. 4th Int.
Darby, H.M., and J.G. Lauer. 2002. Harvest date and hybrid influence on corn forage yield, quality, and preservation. Agron. J. 95:559–566.
Darby, H.M., and J.G. Lauer. 2002. Harvest date and hybrid influence on corn forage yield, quality, and preservation. Agron. J. 95:559–566.
developments. American Society for Microbiology, 50, 294-298.
Doebley, J. F. (1990). Molecular Evidence for Gene Flow among Zea species.
BioScience 40, 443- 448.
Doebley J., 2001 George Beadle's other hypothesis: one-gene, one-trait. Genetics 158:487-493
Doebley, J., and Stec, A. (1991). Genetic analysis of the morphological differences between maize and teosinte. Genetics 129,285-295.
E. D. Thomas, P. Mandebvu, C. S. Ballard, C. J. Sniffen, M. P. Carter, and J.
Beck†. 2001. Comparison of Corn Silage Hybrids for Yield, Nutrient Composition, In Vitro Digestibility, and Milk Yield by Dairy Cows. J. Dairy Sci. 84:2217–2226.
Ehlers, W. 1997: Zum Transpirationskoeffizienten von Kulturpflanzen unter Feldbe-dingungen. Pflanzenbauwissenschaften 1 (3): 97-108.
Fan, L. T., Gharpuray, M. M. & Lee, Y.-H. 1981. Evaluation of pretreatments for for Energy and Industry: 163–165. Carmen, Straubing Germany.
Forestry department of the Food and agricultural organisation (FAO) of the United Nations. Unified bioenergy terminology (UBET). December 2004.
G. W. Roth, and A. J. Heinrichs, 2001. Corn Silage Production and Management Agronomy Facts 18. Department of Crop and Soil Sciences - Cooperative Extension.
Penn State's College of Agricultural Sciences.
Ganoe, K. H., and G. W. Roth. 1992. Kernel milk line as a harvest indicator of corn silage in Pennsylvania. J. Prod. Agric. 5 : 519-523.
Givens, D. I., Cottyn, B. G., Dewey, P. J. S. and Steg, A. 1995. A comparison of the neutral detergent-cellulase method with other laboratory methods for predicting the digestibility in-vivo of maize silage from three European countries. Animal Feed Science and Technology 54:55-64.
H. L. S. Tandon and R. N. Roy. 2004. Integrated Nutrient Management-A Glossary of Terms. Published by the Food and Agriculture Organization of the United Nations, Rome and Fertiliser Development and Consultation Organization, New Delhi, 2004 Hanaki, K., Nagase, M. & Matsuo, T. 1981. Mechanism of inhibition caused by long-chain fatty acids in anaerobic digestion process. Biotechnol. Bioeng. 23(7), 1591–1610.
Hansen, K. H., Ahring, B. K. and Raskin, L. (1999a) Quantification of syntrophic fatty acid-β-oxidizing bacteria in a mesophilic biogas reactor by oligonucleotide probe hybridization. Applied and Environmental Microbiology, 65, (11), 4767-4774.
Hansen, K. H., Angelidaki, I. and Ahring, B. K. (1999b) Improving thermophillic anaerobic digestion of swine manure. Water Research, 33, (8), 1805-1810.
Henderson, A. R., J. W. Ewart, and G. M. Robertson. 1979. Studies on the aerobic stability of commercial silages. J. Sci. Food Agric. 30:223.
Hodges, T. 1991. Temperature and water stress effects on phenology. p. 7–13. In T.
Hodges (ed.) Predicting crop phenology. CRC Press, Boca Raton, FL.
Hoffman, P. C. and L. M. Bauman. 2003. Using NDF digestibility in ration formulation. Focus on forage 6(3).
Hoffman, P. C., Lundberg, K. L., L. M. Bauman, and R. Shaver. 2003. In vitro NDF digestibility of forages: The 30 vs. 48 hour debate. Univ. of WI Extension Focus on Forage Series. Vol. 5, No. 16.
Hunt and co-workers. 1989. Yield, chemical composition and ruminal fermentability of corn whole plant, ear, and stover as affected by maturity. Journal of Production Agriculture. 2:357.
Hunt, C. W., W. Kezar, and R. Vinande. 1989. Yield, chemical composition and ruminal fermkentability of corn whole plant, ear, and stover as affected by maturity. J.
Prod. Agric. 2: 357-361.
Hunt, C.W., W. Kezar, and R. Vinande. 1989. Yield, chemical composition and ruminal fermentability of corn whole plant, ear, and stover as affected by maturity. J.
Prod. Agric. 2:357–361.
Hunt, C.W., W. Kezar, and R. Vinande. 1992. Yield, chemical composition and ruminal fermentability of corn whole plant, ear and stover as affected by hybrid. J.
Prod. Agric. 5:286-290.
Hunter, J.L. Relationship between the stage for corn seed maturation and assimilate supply, assimilate uptake and seed quality. Lexington, 1989, 140p. Thesis (PhD) - University of Kentucky.
Hunter, J.L., Tekrony, D.M., Miles, D.F., Egli, D.B. Corn seed maturity indicators and their relationship to uptake of Carbon-14 assimilate. Crop Science, Madison, v.31, n.5, p.1309-1313, 1991.
Hwu CS, Donlon B, Lettinga G. 1996. Comparative toxicity of long-chain fatty acid to anaerobic sludges from various origins. Water Sci Technol 34(5/6):351–358.
Hwu, C.-S. (1997). Enhancing anaerobic treatment of wastewaters containing oleic acid. Ph.D. Thesis, Wageningen Agricultural University.
Hwu, C.S., Molenaar, G., Garthoff, J., Lier, J.B. van and Lettinga, G. (1997) Thermophilic high-rate anaerobic treatment of wastewater containing long-chain fatty acids: impact of reactor hydrodynamics. Biotechnology Letters 19, 447–451.
Hwu, C.-S., Tseng, S. K., Yuan, C. Y., Kulik, Z. & Lettinga, G. 1998b. Biosorption of long-chain fatty acids in UASB treatment process. Water Res. 32(5), 1571–1579.
Hwu, C.-S., van Lier, J. B. & Lettinga, G. 1998a. Physicochemical and biological performance of expanded granular sludge bed reactors treating long-chain fatty acids. Process Biochem. 33(1), 75–81.
Iltis, H.H. 1983. From teosinte to maize. The catastrophic sexual transmutation.
Science 222: 886–894. J. Dairy Sci. 83(supplement 1):111.
IPCC. (2001). Climate Change 2001 (The Scientific Basis). Cambridge University Press, Cambridge, UK.
J.M.A. Stekar, V. Stibil.J, A. Golob, M. Kodra. 1991. Quality and nutritive value of maize prepared from different hybrids. Options Méditerranéennes - Série Séminaires - n.O 16 - 1991: 137-139
J.W. Schroeder.2004. Corn Silage Management AS-1253, June 2004
Jeyaseelan, S. 1997. A simple mathematical model for anaerobic digestion process.
WaterScience and Technology 35: 185-191.
Johnson, L., J.H. Harrison, C. Hunt, K. Shinners, C.G. Doggett, and D. Sapienza.
1999. Nutritive value of corn silage as affected by maturity and mechanical processing: A contemporary review. J. Dairy Sci. 82:2813–2825.
Johnson, L.M., Harrison, J.H., Davidson, D., Robutti, J.L., Swift, M., Mahanna, W.C., Shinners, K.: Corn silage management I: Effects of hybrid, maturity, and mechanical processing on chemical and physical characteristics. J. Dairy Sci., 2002;
85:833-853.
Johnson, L.M., J.H. Harrison, D. Davidson, J.L. Robutti, M. Swift, W.C.
Mahanna, and K. Shinners. 2002. Corn silage management: I. Effects of hybrid, maturity, and mechanical processing on chemical and physical characteristics. J.
Dairy Sci. 85:833–853.
Johnson, R. R., and K.E.McClure. 1968. Corn plant maturity: IV. Effects on digestibility of corn silage in sheep. J. Anim. Sci.27:535-539.
Jung, H., M. Raeth-Knight, and J. Linn. 2004. Forage fiber digestibility:
measurement, variability and impact. Proc, Minnesota Nutrition Conf: 105-125.
Kellogge E. A. and J. A. Bilrchler 1993 Linking phylogeny and genetics: Zea mays as a tool for phylogenetic studies. Syst. Biol. 42:415-439.
Kerry Greenwood, Geoff Mundy, and Kevin Kelly. 2005. On-farm measurement of
Koch, G., A. Morvarid, and M. Kirchgessner. 1973. (The influence of microorga-nisms of corn on the stability of silage.) Wirtshaftseigene Futter 19:15.
L. T .Evans and R.Fischer 1999 Yield potentials: its definition, measurement and significance. In Crop Sci. 39:1544-1551
Leibensperger, R. Y., and R. E. Pitt. 1987. A model of Clostridial dominance in ensilage. Grass Forage Sci. 42:297.
Lemus, R; Lal, R. 2005. Bioenergy crops and carbon sequestration. Critical Reviews in Plant Sciences, 24 (1): 1-21.
Mangelsdorf, P. C. & Reeves, R.G. (1939). The origin of Indian corn and its relatives. Texas Agric. Expt. Sta. Bull. 574.
Mangelsdorf, P. C. (1974). Corn: its Origin, Evolution and Improvement. Harvard Univ. Press, Cambridge, Mass.
Marchaim U. 1992. Biogas Processes for Sustainable Development. Bull. FAO Agric.
Services, Rome, 95:165-193.
McClintock B., T.A. Kato and A. Blumenschieu. 1981. Chromosome constitutions of races of maize. Its significance in the interpretation of relationships between races and varieties in the Americas. Colegio de Postgraduados, Chapingo, México.
McDonald, I.R., Upton, M., Hall, G., Pickup, R.W., Edwards, C., Saunders, J.R., Ritchie, D.A. and Murrell, J.C. (1999). Molecular ecological analysis of methanogens and methanotrophs in blanket bog peat. Microbial ecology 38: 225-233.
McInerney, M. J. & Bryant, M. P. (1981). Review of methane fermentation fundamentals. In Fuel gas production from biomass, pp. 19±46. Edited by D. L. Wise.
Boca Raton, FL: CRC Press.
McInerney, M. J. & Wofford, N. Q. (1992). Enzymes involved in crotonate metabolism in Syntrophomonas wolfei. Arch Microbiol 158, 344-349.
McInerney, M.J. 1988 Anaerobic hydrolysis and fermentation of fats and proteins. In:
Biology of Anaerobic Microorganisms, A.J.B. Zehnder (ed), John Wiley and Sons p.
373-416.
Morris, M. L. (1998). Overview of the world maize economy. In: Maize Seed Industries in Developing Countries. M. L. Morris (ed). Lynne Rienner Publishers, Inc.
pp. 13-34.
Neureiter, M., dos Santos, J. T. P., Lopez, C. P., Pichler, H., Kirchmayr, R. &
Noike, T., Endo, G., Chang, J. E., Yaguchi, J. I. & Matsumoto, J. I. 1985.
Oba, M and M. Allen. 1997. Evaluation and the importance of the digestibility of neutral detergent fiber from forage. Effects on dry matter intake and milk yield in dairy cows. J. Dairy Sci. 82:589.
Oba, M. and M. S. Allen. 1999. Evaluation of the importance of the digestibility of neutral detergent fiber from forage: effects on dry matter intake and milk yield of dairy cows. J. Dairy Sci. 82:589-596.
Oba, M., and M.S. Allen. 1999. Evaluation of the importance of the digestibility of neutral detergent fiber from forage: Effects on dry matter and milk yield of dairy cows.
J. Dairy Sci. 82:589–596
Oba, M., and M.S. Allen. 2000. Effects of brown midrib 3 mutation in corn silage on productivity of dairy cows fed two concentrations of dietary neutral detergent fiber: III.
Digestibility and microbial efficiency. J. Dairy Sci. 83:1350–1358.
Oechsner, H., A. Lemmer und C. Neuberg, 2003: Feldfrüchte als Gärsubstrat in Biogasanlagen. In: Landtechnik, H. 3, 2003, S. 146-147.
Offer, N. W., Cotterill, B. R. and Thomas, C. 1996. Relationship between silage evaluation and animal response. Proceedings of the 11th international silage conference. (ed. D. I. H. Jones, R. Jones, R. Dewhurst and P. M. Haigh), pp. 26-38.
Institute for Grassland and Environmental Research, Aberystwyth.
Ohshima, M., and P. McDonald. 1978. A review of the changes in nitrogenous compounds of herbage during ensilage. J. Sci. Food Agric. 29:497.
Ohyama, V., and S. Masaki. 1971. Deterioration of silage after opening silo. I.
Changes in temperature and chemical composition in some wilted silages. J.
Jpn. Soc. Grassl. Sci. 17:176.
Ohyama, V., S. Masaki, and S. Hara. 1975. Factors influencing aerobic deterioration of silages and changes in chemical composition after opening silos. J. Sci. Food Agric. 26:1137.
Pavlostathis, S. G. and Giraldo-Gomez, E. (1991) Kinetics of anaerobic treatment:
A critical review. Critical Reviews in Environmental Control, 21, 411-490.
Pedersen, J.F. 1996. Annual forages: New approaches for C-4 forages. p. 246-251.
Philippeau, C., and B. Michalet-Doreau. 1997. Influence of genotype and stage of maturity of maize on rate of ruminal starch degradation. Anim. Feed Sci. Technol. 68:
25-35.
Pouech, P., Fruteau, H. & Bewa, H. 1998. Agricultural crops for biogas Process Biochem. 32: 509–513.
Rinzema, A. and Lettinga, G. 1993. Anaerobic Digestion of Long-Chain Fatty Acids in UASB and Expanded Granular Sludge Bed Reactors, Process Biochemistry, 28, pp. 527-537.
Rinzema, A., Boone, M., van Knippenberg, K. and Lettinga, G. (1994) Bactericidal effect of long chain fatty acids in anaerobic digestion. Water Environment Research, 66, (1), 40-49.
Roth, G. W., and D. Undersander. 1995. Corn silage production, management, and feeding. NCR Publ.574 ASA, Madison, WI
Sasse, L, Kellner, C, Kimaro, A, (1991): Improved Biogas Unit for Developing Countries. (GATE) Deutsches Zentrum fur Entwicklungstechnologien. Eschborn, Germany
Schwab, E. C., and R. D. Shaver. 2001. Evaluation of corn silage nutritive value using MILK2000. Pages 21-24 in Proc. of 25th Forage Production and Use Symposium. WI Forage Council Annual Mtg. Eau Claire, WI.
Schwab, E.C., R.D. Shaver, J.G. Lauer, and J.G. Coors. 2003. Estimating silage energy value and milk yield to rank corn hybrids. Anim. Feed Sci. Tech. 109(1-4):1-18.
Sharma, SK, Mishra, IM, Sharma, MP, Saini, JS, (1988): Effect of particle size on biogas generation from biomass residues. Biomass 17 (1988) 251-263.
Sheperd , A. C. and K. E. McClure. 1996. Effects of an enzyme additive on composition of corn silage ensiled at various stages of maturity. J. Dairy Sci.
79:1767-1773.
Tatsuji Koizumi. 2003. The Brazilian ethanol programme: impacts on world ethanol and sugar markets .FAO COMMODITY AND TRADE POLICY RESEARCH WORKING PAPER No. 1. Commodity Policy and Projections Service Commodities and Trade Division 24 June 2003
Taylor, C. C., J. M. Neylon, J. A. Lazartic, J. A. Mills, R. M. Tetreault, A. J.
Whiter, R. Charley and L. Kung, Jr. 2000. Lactobacillus buchneri and enzymes improves the aerobic stability of high moisture corn.Technol. 36: 253–259.
Tekrony, D.M.; Hunter, J.L.; Viera, R.D. Relationship of black layer maturity to seed vigour across several maize genotypes. In: ASA/CSSA/SSSA ANNUAL MEETINGS, 86. 1994. Seattle. Agronomy abstracts... Madison: American Society of Agronomy, 1994. p.177.
TH. Amon. V. kryvoruchko. B.Amon. W. Zollitsch. K. Mayer. S. Buga und A.
Amid. Biogaserzeugung aus Mais-Einfluss der Inhaltsstoffe auf das spezifische Methanbildungsvermoörgen von früh- bis spätreifen Maissorten. In Bericht über die
54.Tagung 2003 der Vereinigung der Pflanzenzüchter und Saatgutkaufleute Österreichs . BAL Gumpenstein, 25. – 27. November 2003.
Thomas Amon, Vitaliy Kryvoruchko, Barbara Amon, Vitomir Bodiroza, Werner Zollitsch und Josef Boxberger, Wien2006 Biogaserzeugung aus Energiemais 61 LANDTECHNIK 2/ 86-87
Thomas Amon, Vitaliy Kryvoruchko, Barbara Amon, Vitomir Bodiroza, Werner Zollitsch und Josef Boxberger, Wien 2006 . Biogaserzeugung aus Energiemais Thomas Ettle, Frieder Jörg Schwarz. 2003. Effect of maize variety harvested at different maturity stages on feeding value and performance of dairy cows. Anim. Res.
52:337–349.
Van Soest, P.J., J.B. Robertson, and B.A. Lewis. 1991. Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition.
J. Dairy Sci. 74:3583–3597.
W. J. Cox* and J. H. Cherney Timing Corn Forage Harvest for Bunker Silos Published in Agron. J. 97:142-146 (2005).
Weiland, P. 1993 One- and two-step anaerobic digestion of solid agro industrial residues. Water Science and Technology, 27, 145-151.
Weiland, P. 2000 Anaerobic waste digestion in Germany – Status and recent developments. Biodegradation, 11, 415-421.
Wiersma, D.W., P.R. Carter, K.A. Albrecht, and J.G. Coors. 1993. Kernel milk line stage and corn forage yield, quality, and dry matter content. J. Prod. Agric. 6:94–99.
Woese, C.R., O. Kandler, and M.L. Wheelis. 1990. Towards a natural system of organisms: proposal for the domains Archaea, Bacteria, and Eucarya. Proceedings of the National Academy of Sciences U.S.A. 87: 4576-4579.
Yves Barriere. Carine Guillet. Deborah Goffner. Magalie Pichon. 2003. Genetic variation and breeding strategies for improved cell wall digestibility in annual forage crops. A review
Zhao, H., Yang, D., Woese, C. R. & Bryant, M. P. 1993. Assignment of fatty acid-oxidizing syntrophic bacteria to Syntrophomonadaceae fam. nov. on the basis of 16S rRNA sequence analysis. Int. J. Syst. Bacteriol. 43, 278–286.
Zinder, S.H. (1993). Physiological ecology of methanogens. In Methanogenesis:
Ecology, Physiology, Biochemistry and Genetics (ed. J. G. Ferry), pp. 128-206.
Chapman & Hall, New York.