U.S. Egypt Collaborative Research: Increasing P uptake efficiency through mycorrhizal interactions and plant growth promoting bacteria

提高作物种类吸收或利用养分的效率，有可能确保未来具有成本效益和可持续的农业。对于磷(P)来说尤其如此，因为磷是一种重要的植物养分，通常会限制植物的生产力，而用于生产大多数磷肥的磷岩是一种不可再生的资源，目前已知的储量可能在50到100年内耗尽。传统的育种方案往往是根据地上部分在营养充足条件下的活力和表现来选择品种，但一般忽略了根系及其构型以及根系与有益植物微生物的联系。这导致了不太适合低投入农业的品种的发展。植物微生物的相互作用，如丛枝菌根(AM)共生，可以显著提高作物物种的营养效率，改善植物的整体健康和表现。在这里，我们建议使用一种不同的综合方法来提高小麦的营养效率，小麦是世界上最重要的农作物之一。在这项合作研究中，南达科他州立大学的海克·巴克克博士和埃及苏伊士运河大学的萨米·A·M·阿卜杜勒·阿泽姆博士将确定控制小麦对磷的获取和利用效率以及菌根响应性的候选基因，以开发可用于标记辅助选择这些重要农艺性状的工具。此外，还将研究植物生长促生菌对小麦生产力和菌根定植的影响，因为这些细菌对生物有效性低的磷源的动员能力可以协同增强AM真菌对植物磷营养的有利作用。将植物形成AM互作的能力作为一项重要性状纳入育种计划，是考虑到AM共生对寄主植物的非生物(如营养、盐分、干旱)和生物(病原体)胁迫抗性具有许多有利影响，并代表了植物在田间条件下的自然阶段。研究结果将转化为对农民如何通过低成本措施和农艺措施提高作物生产力的建议。该项目将培养两名研究生(一名在美国，一名在埃及)，该项目的国际合作特性将刺激他们发展成为独立的科学家。合作机构的定期访问将保证对实验和项目成果进行协调一致的规划，但也将允许对项目合作伙伴，特别是研究生进行新技术方面的培训。该项目的成果还将纳入南达科他州立大学最近成立的2010年耐旱生物技术中心的研究工作中。小麦最近被培育成该中心的重点作物物种之一，国际合作将刺激该项目以外的进一步合作努力。该奖项由美国-埃及联合基金计划资助，该计划为两国的科学家和工程师进行合作研究提供赠款，并由国际科学和工程办公室(OISE)非洲、近东、南亚(ANESA)部门提供资金。

Increasing the efficiency with which crop species absorb or utilize nutrients has the potential to ensure cost effective and sustainable agriculture in the future. This is particularly true for phosphate (P), because P is an essential plant nutrient that often limits plant productivity, and P rock that is used for the production of most P fertilizers is a nonrenewable resource and the current known reserves are likely to be depleted in 50 to 100 years. Conventional breeding programs often select cultivars based on vigor and performance of the above ground plant part under nutrient replete conditions, but the root system, its architecture and the association of the root system with beneficial plant microorganisms has generally been ignored. This has led to the development of cultivars that are not well suited for low input agriculture. Plant microbe interactions, such as the arbuscular mycorrhizal (AM) symbiosis can contribute significantly to the nutrient efficiency of crop species and improve overall plant health and performance. Here, we propose to use a different and integrated approach to improve the nutrient efficiency of wheat, one of the most important crop species worldwide. The proposal is to study genotypic differences in P efficiency and mycorrhizal responsiveness to determine which cultivar is able to use its plant?]microbe interactions to their maximum potential.In this collaborative research effort, Dr. Heike Bucking at South Dakota State University and Dr. Samy A. M. Abd El-Azeem at Suez Canal University, Egypt, will identify candidate genes that control the acquisition and utilization efficiency of P and the mycorrhizal responsiveness of wheat in order to develop tools that can be used for marker assisted selection of these agronomically important traits. In addition, the effect of plant growth promoting rhizobacteria on wheat productivity and mycorrhizal colonization will be studied because the capability of these bacteria to mobilize P sources with low bioavailability could synergistically enhance the beneficial effects of AM fungi on P nutrition of the plant. Including the capability of plants to form AM interactions as an important trait into breeding programs takes into consideration that the AM symbiosis has numerous beneficial effects on the abiotic (e.g. nutrient, salinity, drought) and biotic (pathogen) stress resistance of their host plant and represents the natural stage of plants under field conditions. Results of the research will be translated into recommendations for farmers how by low cost measures and agronomic practices the crop productivity can be increased. Two graduate students will be trained by this project (one in the U.S. and one in Egypt), and the international collaborative character of this project will stimulate their development into independent scientists. Regular visits of the collaborating institutions will guarantee a cohesive planning of the experiments and of the output of the project, but will also allow training of the project partners and especially of the graduate students in new technologies. Results of the project will also be integrated into the research efforts of the recently established 2010 drought tolerance biotechnology center at South Dakota State University. Wheat has recently been made to one of the focus crop species of the center and the international collaboration will stimulate further collaborative efforts beyond this project.The award is being funded under the US-Egypt Joint Fund Program, which provides grants to scientists and engineers in both countries to undertake cooperative research, and by the Africa, Near East, South Asia (ANESA) division of the Office of International Science and Engineering (OISE).