The effect of humic acids on root growth and endogenous levels of auxin and inhibitory-like substances
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The present paper reports on the effect of complete humic acid extract and medium molecular mass fraction thereof on the growth of sunflower root sections and on the endogenous level of plant growth regulators. Humic acids in nutrient solution, as opposed to humic acids or nutrient solution alone, caused the growth rate in root sections to diminish. Higher concentrations of humic acids proved to have an even stronger inhibitory effect. Root sections treated with 285 mg/L of medium molecular mass fraction showed improved growth and higher endogenous levels of growth-promoting substances than the control. Concentrations as high as 2000 mg/L of complete humic acid extract caused an increase in the endogenous levels of inhibitors. It is suggested that humic acids affect root growth either by altering the metabolism of endogenous plant regulators or by acting as growth-regulating substances themselves.
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Bottini, R., Goleniowski, M., Correa, N.: Levels of growth inhibition in leaves, cambial tissue and flower buds during dormancy in peach trees. Effect of exogenous gibberellic acid.-Phyton 36: 19-24, 1978.
Bystrická, A., Sladkji, Z.: A study of effects of humus substances on root explants of Solanum dulcamara C. -Scripta Fac. Sci. Nat. Ujep Brunensis, Biol. 1: 41-53, 1972.
Dunnett, C.: A multiple comparition procedure for comparing several treatments with a control.- J. Amer. Statist. Ass. 50: 1096-1121, 1955.
Eliasson, L.: Growth regulators in Populus trémula. I Distribution of auxin and growth inhibitors.- Physiol. Plant. 22: 1288-1301, 1969.
Fialová, S.: Influence of sodium humate and nutrient conditions on the content of nucleic acid in wheat roots. -Biol. Plant. 11: 8-22, 1969.
Führ, F., Sauerbeck, D.: The uptake of colloidal organic substances by plant roots as shown by experiment-with "C-labelled humus compounds. Isotopes in Plant Nutrition and Physiology Proceeding of a Symposium Vienna, 1966.
Hártel, O., Hinteregger, J.: Fluorometrische untersuchungen zur aufnahme von humin-komponenten durch die pflanzenzelle.-Phyton (Austria) 18: 199-208, 1978.
Hernando, V., Ortega, C., Fortún, C.: Estudio de la acción ejercida sobre la planta de maíz por el ácido húmico de un estiércol extraído con dos extractantes. I Acción sobre la parte aérea.- Anal. Edafol. Agrobiol. 36: 971-981, 1975.
Hernando, V., Sanchez Conde, M.P., Ortega, B. C.: Acción del ácido húmico sobre la planta de maíz cultivada en soluciones nutritivas equilibradas de concentración superior a la normal. Anal. Edafol. Agrobiol. 28: 835-846, 1969.
Lakatos, B., Meisel, J., Mády, G.: Biopolymer metal complex systems. I Experiments for the preparation of high purity peat humic substances and their metal complexes.- Acta Agron. Hung. 26: 259-271, 1977.
Mylonas, V.A., McCants, C. B.: Effects of humic and fulvic acids on growth of tobacco. I Root initiation and elongation.- Plant Soil 54: 485-490, 1980.
O'Donnell, W. R.: The auxin-like effects of humic preparations from leonardite.- Soil Sci. 116: 107-112, 1973.
Ortega, C., Fortún, C., Polo, A., Dorado, E.: Estudio de las variaciones en el crecimiento de la raíz de guisante producidas por tres ácidos húmicos.- Anal. Edafol. Agroblol. 38: 1399-1407, 1979.
Ortega, C., Ortega, C. M., Fortún, C.: Efecto de los ácidos húmicos de distinta procedencia y sus sales sódicas, sobre la elongación radicular de plántulas de maíz (Zea mays) y veza (Vicia sativa).- Anal. Edafol. Agrobiol. 41: 1027-1033, 1982.
Schnitzer, M., Poapst, P. A.: Effects of a soil compound on root Initiation.- Nature 213: 598-599, 1967.
Steel, R. G. D., Torrie, J. H.: Principles and Procedures of Statistics.- McGraw, Hill Book Co., New York, 1960.
Steimberg, R. A.: Use of lemma for nutrition studies on green plants.- J. Agr. Res. 62: 423-430, 1941.
Stevenson, F. J.: Humus Chemistry, Genesis, Compositions, Reactions.- J. Wiley and Sons, New York, 1982.
Tan, K. H., Nopamornbodi, V.: Effect of different levels of humic acids on nutrient content and growth of corn (Zea mays L.).- Plant Soil 51: 283-287, 1979.
Wallace, A., Wallace, G.A.: The enigma of synthetic metal chelates after 30 years of use in plant nutrition.- Plant Nutrition, Vol. 2. Proc. Ninth Int. Plant Nutr. Colloquium, England, 1982.