Division of Genetics, Indian Agricultural Research Institute, New Delhi
+Present address: School of Life Sciences, Jawaharlal Nehru University, New Delhi-110057.
*Part of the thesis submitted by the senior author to the Post-Graduate School, I.A.R.I., New Delhi in partial fulfilment of the requirements for the Ph.D. degree.
Four varieties of bread wheat (Triticum aestivum) differing in their degree of adaptation were grown at 15, 25 and 35°C and the relative amount of DNA and the turnover of RNA in the root tip cells was studied. Kalyansona, a variety with wide adaptation, shows relative stability in the amount of DNA under different temperatures in comparison to the varieties with limited adaptation. With regard to RNA turnover, all the varieties under study show wide variation with temperature and the magnitude of such variation is high in Kalyansona compared to other varieties. It is suggested that the ability to maintain a stable amount of DNA and to show plasticity in RNA turnover can be the criteria of wide adaptation.
