Delayed bolting in Rocket for improved quality and greater sustainability.

延迟 Rocket 中的螺栓连接，以提高质量和更大的可持续性。

• 批准号: BB/I016120/1
• 金额: $ 11.71万
• 依托单位: University of Warwick
• 依托单位国家: 英国
• 项目类别: Training Grant
• 财政年份: 2011
• 资助国家: 英国
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FI016120%2F1
• 关键词: Delayed; bolting; Rocket; improved; quality

Flowering time in crop plants is agronomically important because it impacts on quality, yield and scheduling of production. Research into the molecular pathways controlling flowering time in the model plant Arabidopsis has progressed rapidly over the past 20 years and has led to a much greater understanding of the genetic regulation of flowering. However, to date there has been little translation of this huge investment in Arabodopsis research into real benefits in crop plants. Premature bolting (flowering) of rocket before it is harvested is a major problem for growers, as secondary metabolites are produced in the leaves which give the plant a bitter and unpleasant taste and render the crop unsaleable. Delayed bolting is a desirable trait in commercial rocket varieties as it preserves the quality of rocket leaves sold for consumption in leafy salads, and increases sustainability by reducing wastage caused by premature bolting of crops in the field. Several genes have been identified which, if mutated, result in delayed flowering in Arabidopsis. These include genes involved in the photoperiodic pathway, the vernalisation pathway, the autonomous pathway, and genes responsible for integrating the floral pathways. Many of these genes have been cloned from Arabidopsis and homologues of some of these genes have been identified in a diverse range of species, including monocots, where they have been shown to have similar, or conserved roles in regulating flowering time. This project will exploit the knowledge of molecular pathways controlling flowering gained from model plants such as Arabidopsis, and also from the knowledge gained about genes controlling bolting in lettuce (which is part of a current BBSRC funded project in the Supervisors lab), to identify novel alleles of flowering time genes that have either been induced through mutagenesis, or have arisen naturally, that can be used to delay bolting in rocket. This will be done through the following approaches; a). An EMS mutagenised population will be screened for late bolting lines that have been created as a result of the mutagenesis treatment. b). Flowering time genes will be identified and isolated from Rocket, this will be done through homology to known flowering time genes in Arabidopsis which is a close relative of Rocket. c). A Rocket diversity set will be screened for natural variation affecting bolting time. d). Sequences of flowering time genes in the late bolting Rocket lines that have been isolated from a). and c). will be analysed to identify polymorphisms that may be the cause of the late bolting phenotype. This may be done through comparing the transcriptome sequence of the late bolting lines with WT lines, and/or PCR-based cloning and sequencing of the target genes. e). Polymorphisms in flowering time genes will be followed through a back-crossing programme to see if they co-segregate with the late bolting phenotype and thus could be causing the late bolting. f). Late bolting Rocket lines will be grown in commercially managed field trials to test the robustness of the late bolting in different field conditions. g). The effect of delayed bolting on senescence in rocket will be investigated through the analysis of the expression of senescence-associated genes in the late bolting lines. The principle objectives/outputs of this research project are; i). The identification of Rocket genes controlling bolting time. ii). The creation of late bolting lines in a commercially relevant Rocket cultivar which can readily be incorporated into breeding programmes to generate new varieties with delayed bolting. iii). The identification of naturally occurring alleles of known flowering time genes that have a robust effect on bolting time in different genetic backgrounds. iv). To examine the advantages conferred by delayed bolting in terms of reduced crop losses and possibly also through effects on leaf senescence.

作物的开花时间在农学上是重要的，因为它影响到质量、产量和生产调度。在过去的20年里，对模式植物拟南芥中控制开花时间的分子途径的研究取得了迅速的进展，并使人们对开花的遗传调控有了更多的了解。然而，到目前为止，很少有人将这种对阿拉伯紫质研究的巨大投资转化为对农作物的真正好处。火箭在收获前过早抽苔(开花)对种植者来说是一个主要问题，因为叶片中会产生次生代谢物，这会给植物带来苦涩和令人不快的味道，使作物无法销售。延迟抽苔是商业火箭品种的一个可取特征，因为它保留了销售用于多叶沙拉的火箭叶的质量，并通过减少田间作物过早抽苔造成的浪费增加了可持续性。已经确定了几个基因，如果发生突变，就会导致拟南芥延迟开花。这些基因包括参与光周期途径、春化途径、自主途径的基因，以及负责整合花途径的基因。其中许多基因已经从拟南芥中克隆出来，其中一些基因的同源基因已经在包括单子叶植物在内的各种物种中被鉴定，它们在调节开花时间方面具有相似或保守的作用。该项目将利用从拟南芥等模式植物获得的控制开花的分子途径的知识，以及从控制生菜抽苔的基因获得的知识(这是目前BBSRC资助的Supervisors实验室项目的一部分)，以确定开花时间基因的新等位基因，这些基因要么是通过诱变诱导的，要么是自然产生的，可以用来推迟火箭的抽苔。这将通过以下方法实现：a)。将对EMS诱变群体进行筛选，以寻找由于诱变处理而产生的晚抽苔系。b)。将从Rocket中鉴定和分离开花时间基因，这将通过与Rocket的近亲拟南芥中已知的开花时间基因同源来完成。c)。将对火箭多样性集合进行筛选，以确定影响抽苔时间的自然变化。d)。从A)中分离的晚抽苔型火箭品系中的开花时间基因序列。和c)。将进行分析，以确定可能是晚抽苔表型的原因的多态。这可以通过比较晚抽苔系和WT系的转录组序列，和/或基于PCR的目的基因的克隆和测序来实现。e)。花期基因的多态将通过回交程序进行跟踪，以确定它们是否与晚抽苔表型共分离，从而可能导致晚抽苔。f)。后期螺栓火箭生产线将在商业管理的现场试验中种植，以测试后期螺栓在不同野外条件下的稳健性。g)。通过对晚抽苔系衰老相关基因表达的分析，探讨延迟抽苔期对火箭衰老的影响。本研究项目的主要目标/产出是：i)。控制抽苔期的火箭基因的鉴定。Ii)。在商业上相关的火箭品种中创建晚抽苔系，该品系可以很容易地纳入育种计划，以产生延迟抽苔的新品种。三)。鉴定在不同遗传背景中对抽苔时间有显著影响的已知开花时间基因的自然发生等位基因。四)。研究延迟抽苔在减少作物损失方面的优势，并可能通过对叶片衰老的影响来实现。