Influence of sodium humate and nutritive conditions on the content of nucleic acids, particularly on the ribosomal ribonucleic acid in wheat roots

Abstract

Changes in the nucleic acid (NA) content were studied in roots of young wheat plants cultivated under various nutritive conditions, namely in a nutrient solution, in distilled water and in a solution of sodium humate in distilled water. Changes in the ribosomal ribonucleic acid (RNA) in particular and their connection with growth rate were investigated. The amount of the NA fraction investigated (more than 90 per cent of which is represented by the ribosomal RNA) changed substantially under the cultivation conditions studied. In roots of one plant cultivated in water the content of the NA fraction investigated was at the most about 25 μg and it began to decrease as early as from the second day of cultivation. After 12 days of cultivation it decreased to 15 μg. When cultivated in Na-humate the roots contained at the most 33 μg NA, between the 5th–7th day, followed by an intensive decrease after 12 days, to 17 μg. The content of the fraction investigated in wheat plants cultivated in a nutrient solution was about double the value in comparison to these two cases with the maximal value about 60 μg between the 7th–9th day. After 12 days this amount decreased to 45 μg.