| Abstract: | Improvement of crop water use efficiency (WUE) has not been successful because evaluation for this component of drought resistance is unreliable in field-grown plants. The composition of stable isotopes of plant carbon (delta(13)C) was earlier shown to be an excellent indicator of WUE in tomato and other species. It is now reported that delta(13)C can be satisfactorily predicted from three restriction fragment length polymorphisms (RFLPs), which are genetic markers for discrete DNA sequences within the genome. An additive type of gene action was observed for all three RFLP markers, and for one of them there also was a significant nonadditive component. Combining the delta(13)C and RFLP technologies may aid in identifying genes associated with WUE and in studying mechanisms contributing to WUE. These technologies will also be useful for crop improvement. |
