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Abstract

A recent proteomic analysis of germinating Arabidopsis thaliana seeds demonstrates the effectiveness of functional genomics for investigating the complexity of developmental regulatory networks, such as the development of the embryo into a young plant. The electronic version of this article is the complete one and can be found online at http://genomebiology.com/2001/3/1/reviews/1002 © BioMed Central Ltd (Print ISSN 1465-6906; Online ISSN 1465-6914) In flowering plant development, seed germination is the transition of the quiescent embryo, which has developed from the fertilized ovule, into a new photosynthetically active plant. The visible sign that germination has been completed is the protrusion of the radicle, the precursor of the root, through the seed coat; germination sensu stricto begins, however, with water uptake by the seed (imbibition) and ends with the start of elongation the embryonic axis inside the seed [1]. Germination results from a combination of many cellular and metabolic events, coordinated by a complex regulatory network that includes seed dormancy, an intrinsic ability to temporarily block radicle elongation in order to optimize the timing of germination [2]. In the field of seed biology, germination mechanisms and their control by dormancy have been investigated in a wide range of species. Nonetheless, how these processes are coordinated, how they contribute to germination, and the regulatory network leading to completion of germination remain poorly understood.The availability of the complete genome sequence of the model plant Arabidopsis thaliana [3], together with the development of high-throughput procedures for global analyses of gene function, has launched the 'post-genomic' era of plant biology. Systematic analyses of RNA and protein expression patterns, and of post-translational modifications, are now feasible for a large set of genes [4]. These can provide important clues about protein-protein interactions and gene functions in a complex developmental context. A recent proteome study of germinating Arabidopsis seeds [5] highlights the effectiveness of using this model organism to provide information on germination that may prove general to all plants. The physiology of seed germinationIn temperate climates, most mature seeds, consisting of an embryo surrounded by endosperm and a seed coat (testa), are dispersed from the mother plant in a state of low moisture content (5-15%) and with metabolic activity at a standstill. Some physiologists have hypothesized that with regard to their structure, genetic information and macromolecular content, dry seeds are in a state of readiness to resume metabolism [6]. For germination to occur, quiescent seeds need only be hydrated under conditions that encourage metabolism, such as a suitable temperature and the presence of oxygen (Figure 1). The uptake of water by the seed, which is considered to be a trigger for germination, and the metabolic processes that take place as a result, are described in Figure 1. Seed germination can be de...

Germination and Seedling Growth of Genotypes Crambe abyssinica Submitted to Water Deficit

“…imbibition tends to decelerate (Bewley, 1997;Bove et al, 2001). In this study, the reduction of germination reported for the FMS Brilhante, FMS CR 1307, 1312 and 1326 genotypes in the control group (Ψs = 0 MPa) may have occurred due to fast seed imbibition, which can cause damages to the embryo, as reported by Bewley and Black (1994).…”

A comparative proteome and phosphoproteome analysis of differentially regulated proteins during fertilization in the self‐incompatible species Solanum chacoense Bitt.

“…Therefore, only the study of the proteins themselves provides information on their real amount and/or activity at a given time in a given tissue, or in response to a given stimulus or treatment [5]. Proteomic analyses also offer the opportunity to examine simultaneous changes in protein accumulation occurring in complex developmental processes, and to determine informative temporal expression patterns [6]. One of the most important developmental processes in plants is exemplified by the formation of the seed.…”

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“…Below 20 ºC the time to obtain t 50 was increased and above 40 ºC, average germination was not reached by any of the two varieties ( Figure 2). Bois et al (2006) (Bove et al, 2001;Rosa et al, 2004;Taiz & Figure 2. Time required for middle germination or t 50 at each temperature.…”

“…However, those that maintain high percentages of germination at temperatures far from optimum might have a higher capacity to survive in warm or cold environments (Mamedi et al, 2017). In this case, basal and optimum temperatures were similar for both varieties, nonetheless, the maximum temperature was of 48.8 ºC for Suyana and of 62.2 ºC for Tunkahuan, suggesting that the crop of this last variety can be successful in warm or dry climates and that both of them can prosper in cold climates, mRNA que participan en la activación de enzimas que degradan los compuestos de reserva y translocan energía al embrión (Bove et al, 2001;Rosa et al, 2004;Taiz y Zeiger, 2010 Para una especie o cultivar, el conocimiento de las temperaturas cardinales resulta importante para predecir sus áreas de distribución con posibilidades de éxito (Singh et al, 2008). El intervalo de temperatura donde ocurre la germinación óptima es único en cada cultivar y la exposición a temperaturas subóptimas o supraóptimas podría afectar negativamente la germinación de las semillas.…”