Exploitation of interspecific biodiversity for wheat improvement

到2050年，世界人口将从60亿增加到90亿，因此粮食产量需要在目前的水平上增加70%。此外，气候变化和需要发展低投入的耕作方式将大大减少小麦等作物的产量。不幸的是，由于现代育种实践，现代小麦品种中相对较少的遗传变异可供育种者开发出优越的适应性基因型。小麦的野生近缘种（外来种）提供了大量尚未开发的遗传变异库（如对非生物和生物胁迫的耐受性、生物量、产量和光合潜力）。这种变异可用于开发适应气候变化和环境友好型农业做法的新的高产品种。以前从外来物种向小麦成功渗透的例子包括：伞形盾叶锈病抗性（使美国小麦生产免于1960年的灾难性失败）；对一系列疾病的抗性，对酸性土壤的耐受性和黑麦产量的增加优势（在20世纪90年代后期，世界上大多数小麦品种都存在1B/1R易位，并且在“Rialto”等主要品种中仍然存在）；一个来自伊蚊的基因。在许多小麦品种中存在具有抗眼斑的心室；欧洲的许多顶级小麦品种，例如“Robigus”携带来自小麦（Triticum dicoccoides）基因渗入的基因。BBSRC最近资助了一个研究项目，旨在将小麦的遗传变异从其野生亲缘种转移到小麦上。这些品系最终将用于开发适应气候变化和环境友好型耕作方式的优质高产小麦新品种。这个资助的研究项目正在开发1)大量的小麦/外来杂交品种，通过小麦与其远亲杂交产生，2)一系列携带来自一系列外来物种的单染色体片段的小麦品系。为了充分发挥这一计划的潜力，必须在多种环境中筛选所产生的小麦/外来种质的多种性状。为了做到这一点，目前的申请将组建一个国际作物生理学集群，包括英国、澳大利亚和印度的小组。虽然这项研究将有全球应用，但这个项目的重点将集中在开发优良的印度小麦品种。近年来，印度的小麦生产停滞不前，新品种未能显著提高产量潜力，主要原因是生物和非生物胁迫的不利影响。因此，引进能够抵抗这些压力的外来种质对印度未来的小麦生产至关重要。该小组将研究和筛选正在开发的小麦/外来种质的一系列特性，包括耐热、耐旱（包括水利用效率）、酸碱土壤和盐；抵抗疾病；提高光合能力/生物量产量和氮利用效率。作为这项研究的结果，作物生理集群将能够识别携带基因的特定外来染色体片段，例如赋予对生物/非生物胁迫的抗性/耐受性等。这些外来染色体片段将直接纳入印度DWR和ARI的小麦育种计划。此外，从该计划中获得的数据将被反馈给BBSRC资助的种质资源计划，特别是给与该计划有关的英国育种者进行商业开发。这种材料也将被澳大利亚育种者利用，从而在BBSRC和谷物研究与发展公司（GRDC）之间提供进一步的联系。

The world's population is set to increase from 6-9 billion by 2050 and thus food production needs to increase by 70% over its present levels. In addition, climate change and the need to develop lower-input farming practises will significantly reduce the production of crops such as wheat. Unfortunately, due to modern breeding practises relatively little genetic variation is available in modern wheat varieties for breeders to develop superior adapted genotypes. The wild relatives (alien species) of wheat provide a vast and largely untapped reservoir of genetic variation (for traits such as tolerance to abiotic and biotic stress, biomass, yield and photosynthetic potential). This variation can be exploited for the development of new high yielding varieties adapted to climate change and environmentally friendly agricultural practises. Examples of previously successful introgressions from alien species into wheat include leaf rust resistance from Aegilops umbellulata (which saved US wheat production from catastrophic failure in 1960); resistance to a range of diseases, tolerance to acid soils and increased yield advantage from rye (in the late 1990s a 1B/1R translocation was present in the majority of the world's wheat varieties and is still present in leading varieties such as "Rialto"); a gene from Ae. ventricosa conferring resistance to eyespot is present in many wheat varieties; many of the top wheat varieties in Europe, e.g. "Robigus", carry genes derived from introgressions from Triticum dicoccoides. The BBSRC have recently funded a research programme aimed at transferring genetic variation to wheat from its wild relatives. These lines will ultimately be exploited to develop new superior high yielding wheat varieties which are adapted to climate change and environmentally friendly farming practises. This funded research programme is in the process of developing 1) large numbers of wheat/alien hybrids, produced by crossing wheat with its distant relatives, and 2) a series of lines of wheat carrying single chromosome segments derived from a range of alien species. For the full potential of this programme to be realised it is essential that the wheat/alien germplasm being generated is screened for a diverse range of traits in multiple environments. In order to do this the present application will assemble an international crop physiology cluster involving groups in the UK, Australia and India. While the research will have global application the emphasis of this programme will focus on developing superior Indian wheat varieties. Over recent years wheat production has stagnated in India with new varieties failing to provide significant improvements in yield potential primarily because of the adverse affects of biotic and abiotic stresses. The introduction of alien germplasm which combats these stresses is thus of critical importance for future wheat production in India.This group will undertake research and screen the wheat/alien germplasm being developed for a range of traits including tolerance to heat, drought (including water use efficiency), acid and alkaline soils and salt; resistance to disease; increased photosynthetic capacity/biomass production and nitrogen use efficiency.As a result of this research the crop physiology cluster will enable the identification of specific alien chromosome segments that carry genes that e.g. confer resistance/tolerance to biotic/abiotic stresses, etc. These alien chromosome segments will be directly incorporated into wheat breeding programmes in India at DWR and at the ARI. Furthermore, the data obtained from this programme will be channelled back into the BBSRC funded germplasm programme and in particular to the breeders associated with it in the UK for commercial exploitation. The material will also be exploited by Australian breeders thus providing a further link between the BBSRC and the Grain Research and Development Corporation (GRDC).