TRANSCRIPTIONAL REGULATION OF RESILIENCE TO PHOTO-INHIBITION UNDER CHILLING CONDITIONS IN MAIZE.

玉米在寒冷条件下对光抑制的抵抗力的转录调控。

基本信息

批准号：
MR/T042737/1
负责人：
Johannes Kromdijk
金额：
$ 155.29万
依托单位：
University of Cambridge
依托单位国家：
英国
项目类别：
Fellowship
财政年份：
2020
资助国家：
英国
起止时间：
2020 至无数据
项目状态：
未结题

来源：
https://gtr.ukri.org/projects?ref=MR%2FT042737%2F1
关键词：
TRANSCRIPTIONAL REGULATION RESILIENCE PHOTO INHIBITION

项目摘要

Global food demand is expected to increase substantially over the coming decades, with a predicted increase in human population from 7.5 billion currently to 10 billion by 2050 and significant shifts to increasingly calorie-rich diets. This comes at a time when productivity increases of several major food crops through conventional breeding have slowed down and global climate change is putting additional pressures on food production, especially via extreme weather events. Investing in sustainable and resilient crop productivity per unit land area is urgently needed, if humanity is to successfully avert future global food crises.The C4 crop Zea mays (maize) is currently the dominant global crop with a world-wide production volume of 1.09 billion metric tons. Crop species with the C4 photosynthetic pathway circumvent some of the inefficiencies of the Calvin-Benson-Bassham cycle by concentrating carbon dioxide around its central enzyme Rubisco. The physiological advantages of C4 species, such as high efficiency of photosynthetic light, water and nitrogen use, have allowed several of these species to become agriculturally relevant crops or weeds, and to dominate many of the open landscape biomes across warmer regions of the earth. They also form the rationale for attempts to improve productivity of C3 crops such as rice, by installing C4 biochemistry and anatomy.However, crops originating from the tropics and sub-tropics are often sensitive to chilling temperatures, in particular in combination with exposure to light which gives rise to chilling-induced photoinhibition, i.e. prolonged periods where plants are incapable of doing photosynthesis and are very sensitive to damage by absorbed sunlight. Maize was domesticated by ancient farmers in Mexico approximately 9000 years ago and is one of the most susceptible crops to chilling-induced photoinhibition amongst those grown in temperate regions. As a result, maize yields at higher latitudes are limited by a relatively short growing season and maize is sensitive to yield losses due to early and late season cold snaps and poor early season establishment of sufficient leaf area to efficiently capture light and compete with weeds.Improving chilling tolerance in maize will have strong economic impact by increasing the latitudinal range of maize and by helping to reduce year by year yield variability. It has been known for a long time that considerable variability in chilling tolerance and photoinhibition sensitivity exists amongst different maize accessions, often reflecting the climate at the region of cultivar development, such as between dent varieties from the US corn belt and flint varieties developed in more temperate regions like Northwest Europe, Canada or Argentina, but the mechanistic and genetic basis of this variation still remains largely undefined. The central aim of this project is to improve understanding of genetic differences in sensitivity to chilling-induced photoinhibition to aid development of superior maize germplasm for temperate regions.This project will use a novel maize population with structured genetic variation to identify differences in traits involved in chilling-induced photoinhibition that are statistically correlated to genetic variation. Similarly, variation in gene expression levels will be measured and correlated to sequence variation at specific genomic locations. Using these parallel experimental approaches under field and controlled environment conditions, the project will identify specific genes that are central in controlling gene expression in response to chilling and high light, as well as pinpoint which genomic locations in maize show variation that correlates with the expression of these control genes. The projects outcomes will increase availability of genetic markers for breeding of chilling-tolerant traits, as well as enhance understanding of the role of gene expression responses in improving chilling-tolerance in maize.

预计在未来几十年中，全球粮食需求预计将大幅增加，预计人口从目前的75亿升至2050年的100亿，并大幅转变为越来越高的卡路里饮食。这是在通过传统繁殖减慢的几种主要粮食作物的生产率提高，而全球气候变化正在给粮食生产带来额外的压力，尤其是通过极端天气事件。如果人类将成功避免未来的全球粮食危机，则迫切需要对可持续和韧性农作物生产率进行投资。C4裁剪Zea Mays（玉米）目前是全球主要农作物，全球生产量为10.9亿吨。带有C4光合途径的作物物种通过将二氧化碳围绕其中央酶rubisco浓缩来规避Calvin-Benson-Bassham循环的某些效率低下。 C4物种的生理优势，例如光合光，水和氮的使用效率高，使其中几种物种成为农业相关的农作物或杂草，并在地球较温暖地区的许多开放式景观生物群落中占主导地位。它们还构成了试图通过安装C4生物化学和解剖学来提高C3作物生产率的基本原理。通过吸收的阳光损坏。大约9000年前，玉米被墨西哥的古代农民驯化，是在温带地区生长的人中最容易受到寒冷引起的光抑制的作物之一。结果，较高纬度的玉米产量受到相对较短的生长季节的限制，并且玉米对由于早期和后期的冷阵和较差的季节早期建立足够的叶子面积的建立而敏感，以有效地捕捉光线并与杂草竞争。很长一段时间以来，在不同的玉米加入中存在耐寒性和光抑制敏感性的差异很大，通常反映了品种开发区域的气候，例如美国玉米腰带的凹痕品种与弗林特品种之间在欧洲，加拿大，加拿大或阿尔氏菌等较高的温度下发展的浓度，但仍然是这种变体的基础，但这种变化仍然存在。该项目的核心目的是提高人们对寒冷诱导的光抑制敏感性的遗传差异的理解，以帮助开发温带地区的上玉米种质，以使用具有结构性遗传变异的新型玉米种群来识别与遗传性抑制性的遗传抑制性差异的差异，从而确定统计上的遗传差异。同样，将测量基因表达水平的变化并与特定基因组位置的序列变化相关。使用这些平行的实验方法在田间和受控环境条件下，该项目将识别特定的基因，这些基因在控制基因表达方面响应寒冷和高光，以及玉米中哪些基因组位置显示与这些控制基因的表达相关的变化。这些项目的结果将增加遗传标志物的可用性，以繁殖耐寒性特征，并增强对基因表达反应在改善玉米耐寒性耐受性中的作用的理解。