BREAD: Development of Novel Salt-tolerant Forage and Cereal Crops

Pi：Jan Dvorak(加州大学戴维斯分校)合作伙伴：Luming-cheng Luo和Patrick E.McGuire(加州大学戴维斯分校)、Muhammad Javed Iqbal(北达科他州立大学)、Makhdoom Hussain(小麦研究所，巴基斯坦费萨拉巴德)和Shahzada Munawar Mehdi(巴基斯坦土壤盐分研究所)合作者：Edward J.DePeter、Emanuel Epstein和William D.rains(加州大学戴维斯分校)和Dennis Falaschi(加利福尼亚州Firebaugh帕诺什水区)，以及Dennis Falaschi(加利福尼亚州火堡帕诺什水区)。在该项目的伙伴国巴基斯坦，2100万公顷的土地中有200万公顷是盐碱化的，不适合或仅略微适合农业。盐碱地可以通过适当的农艺措施和工程干预措施以及/或通过种植耐盐作物来开垦。不幸的是，由于主要农作物固有的盐敏性，提高其耐盐性的速度慢得令人失望。该项目采取了一种相反的策略，通过改善天然耐盐植物的农艺属性。多年生高大冰草及其近亲具有特殊的耐盐性，其中一些在盐碱环境中生产大量牧草。高大冰草的一项独特资产是它们可以与小麦杂交，生产出通常具有异常耐盐性的植物材料。虽然小麦和冰草的染色体不会自然重组，但这些物种的染色体之间的重组可以通过使用包含同源配对基因PH1突变的遗传库来诱导。本项目的目标是评估利用Su1-PH1(PH1抑制因子)系统利用冰草和小麦杂交获得的重组基因组开发新的耐盐种质的可能性。从这些杂交组合产生的双倍体将通过细胞遗传学和遗传方法以及矿物质含量、营养品质和农艺性状来表征。将在加利福尼亚州和巴基斯坦进行实地评估。在遗传分析方面，将对冰草基因组进行测序，并开发针对冰草种质的遗传标记。该项目的影响将远远超出在巴基斯坦盐碱地上开发农业技术和材料的范围。将产生和传播关于小麦和外来染色体之间重组的遗传操作的基本知识，目的是利用重组基因组产生新的植物形式。这些知识可以应用于小麦与麦草以外的物种的杂交，以生产具有更好的耐旱性、耐热性、耐寒性或耐湿性的新型谷物，或具有新的属性，如多年生生长习性。该项目开发的耐盐材料将有助于未来发现控制冰草高耐盐性的基因，并将其应用于小麦和其他作物的生物技术中，此外，这些种质还将立即用于巴基斯坦和其他盐碱地国家的育种计划。冰草基因组序列和冰草遗传标记将存放在NCBI(http://www.ncbi.nlm.nih.gov)and)项目网站上，并分别在GrainGenes(http://wheat.pw.usda.gov/GG2/index.shtml))和Gramene(http://www.gramene.org)，)中提供链接。遗传物质将被提供用于长期储存和分发给堪萨斯州立大学的国家植物种质系统和小麦遗传和基因组资源中心。

PI: Jan Dvorak (University of California, Davis)Co-PIs: Ming-Cheng Luo and Patrick E. McGuire (University of California-Davis), Muhammad Javed Iqbal (North Dakota State University), Makhdoom Hussain (Wheat Research Institute, Faisalabad, Pakistan), and Shahzada Munawar Mehdi (Soil Salinity Research Institute, Pakistan)Collaborators: Edward J. DePeters, Emanuel Epstein, and William D. Rains (University of California-Davis), and Dennis Falaschi (Panoche Water District, Firebaugh, CA) Salinity limits agriculture in many semiarid areas of the world. In Pakistan, the partner country of this project, two million hectares (ha) of the total 21 million ha of land are salinized and are either unsuitable or only marginally suitable for agriculture. Salinized land can be reclaimed with appropriate agronomic practices and engineering interventions and/or by growing salt-tolerant crops. Unfortunately, improvement of salinity tolerance of major crops has been disappointingly slow because of their inherent salt sensitivity. This project takes a reverse strategy by improving agronomic attributes of plants naturally able to tolerate salinity. Perennial tall wheatgrasses and their close relatives have exceptional salt tolerance and some produce a large quantity of forage in saline environments. A unique asset of tall wheatgrasses is that they can be hybridized with wheat, producing plant materials that are often exceptionally salt tolerant. While the chromosomes of wheat and wheatgrasses do not recombine naturally, recombination between chromosomes of these species can be induced through the use of genetic stocks containing mutations in the homoeologous pairing gene Ph1. The goal of this project is to evaluate the possibility of developing novel salt-tolerant germplasm with recombined genomes derived from hybridization between wheatgrass and wheat using the Su1-Ph1 (Suppressor of Ph1) system. Amphiploids developed from these crosses will be characterized by cytogenetic and genetic approaches as well as for mineral content, nutritional quality, and agronomic traits. Field evaluations will be conducted in California and in Pakistan. For genetic analysis, wheatgrass genomes will be sequenced and genetic markers specific for wheatgrass germplasm will be developed. This project will have an impact reaching far beyond developing technology and materials for agriculture on saline soils in Pakistan. Basic knowledge about genetic manipulation of recombination between wheat and alien chromosomes with the objective of producing novel plant forms with recombined genomes will be generated and disseminated. This knowledge can be deployed in hybridization of wheat with species other than wheatgrasses in order to produce novel cereals with improved tolerance of drought, heat, cold, or waterlogging or with novel attributes, such as perennial growth habit. The salt-tolerant materials developed in this project will facilitate future discovery of genes controlling high salt tolerance in wheatgrasses and their deployment in biotechnology of wheat and other crops in addition to the immediate use of this germplasm in breeding programs in Pakistan and other countries with saline soils. Wheatgrass genome sequences and the wheatgrass genetic markers will be deposited at NCBI (http://www.ncbi.nlm.nih.gov)and on the project website with links in GrainGenes (http://wheat.pw.usda.gov/GG2/index.shtml) and Gramene (http://www.gramene.org), respectively. Genetic materials will be offered for long term storage and distribution to the National Plant Germplasm System and the Wheat Genetic and Genomic Resources Center, Kansas State University.