A lack of nuclear DNA content variability among wheat near isolines differing in aluminium response

Nucleotypic variation has been speculated to play a role in the adaptation of crop species to environmental stress. The objective of this study was to determine if nuclear DNA content variability was associated with aluminium (Al) tolerance in wheat. Six wheat (Triticum aestivum L.) near isolines (d iffering in Al response), two recurrent parents (Al sensitive), and one don or parent (Al tolerant) were all analysed for nuclear DNA content using flo w cytometry. A 1.7% variation in nuclear DNA content was observed among the nine wheat lines. No association between Al response and nuclear DNA conte nt was observed. All of the wheat near isolines had a nuclear DNA content s imilar to their recurrent parent. The wheat genome appears to be stable wit h no unusual inheritance of nuclear DNA content observed. Flow cytometric a nalysis proved to be sensitive enough to detect nuclear DNA content variabi lity at the level of 0.5% variation among wheat lines. (C) 1999 Annals of B otany Company.