Location: Plant Genetics ResearchTitle: Screening The Aegilops-Triticum Group For Boron Tolerance) Author
Submitted to: Indian Journal of Genetics and Plant Breedings
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/1/2011
Publication Date: N/A
Citation: Interpretive Summary: Genetic diversity within cereals represents the heritable variation within and between wild and cultivated populations of cereals. Knowledge of the genetic diversity and population structure present in germplasm collections is a critical foundation for future wheat improvement. It is clear that any progress in new cultivar development will require a well characterized genetic base as the backbone of any successful wheat improvement program. Boron deficiency in wheat is a critical problem for wheat production in Bangladesh and other high rainfall regions including many areas of the subtropics. The present investigation was designed to evaluate 91 diverse genotypes from within the Aegilops and wild wheat species and to identify the most efficient boron genotypes to be utilized in developing boron tolerant cultivars for Bangladesh and other regions of the world where wheat is being grown on low boron soils. The project results were very clear in that there is considerable genetic variation within wild and cultivated cereals, and that breeders should be able to transfer the desired gene complexes into modern cultivated wheat. The potential for improving cereal production in Bangladesh was also studied by adding 3 kg of boron per hectare to commercial fields of wheat. Results clearly showed that by adding boron to Bangladesh wheat fields, yields were increased from 10-20% using current management practices. This project is capable of significantly increasing food production in Bangladesh and improving income for farmers. The resulting techniques and boron tolerant species will be made available to US wheat improvement programs.
Technical Abstract: Boron deficient and toxic soils pose a critical problem in wheat production on a world scale. Therefore, 79 accessions from 12 diverse wild wheat (Aegilops speltoides, Ae. longissima, Ae. sharonensis, Ae. bicornis, Ae. searsii, Ae. kotschyi, Ae. peregrina ssp. cylindrostachys, Ae. peregrina ssp. euvariabilis, Ae. geniculata syn. ovata, Ae. biuncialis, Ae. triuncialis, Triticum turgidum ssp. dicoccoides) species collected from 7 different countries (Israel, Turkey, Syria, Jordan, Egypt, Lebanon and Iran) were subjected to root length studies analyzed by a hydroponic system in order to identify boron tolerant/efficient species using 0 mM B, 3 mM B and 10 mM B solutions and establish the potential of hydroponics for utilization in wild grass species root length studies. No genotype from any species grew long healthy roots in 10 mM B. The longer root length group (15.1-22.8 cm) regarded as B tolerant, the short root length group (0-10 cm) as B susceptible, and the medium root length group (10.1-15.0 cm) was considered as moderately B tolerant/susceptible. The results indicated that wild species Ae. longissima, Ae. bicornis, Ae. kotschyi, and Ae. geniculata syn. ovata are significantly more tolerant to excess boron than any of the other species analyzed and could be useful as parents for the development of B efficient/tolerant varieties. The vagaries associated with screening and evaluating wild grass species in hydroponics are discussed. In addition, the potential of adding boron directly to subsistance farmers wheat fields over several years was evaluated.