Using the example of Witold Gombrowicz‘s
Diary
, this essay argues that not all autobiographical texts try to eliminate fictionality and form an autobiographical pact with the reader. The Diary is ...not a depository of facts, a medium of self-confession, or an instrument of self-discovery. It is a type of autobiographical writing that deploys various devices of stylization and genre experimentation to provoke the reader and the writer, unsettle their habits, and draw out their artificialities. The goal of this provocation is to stimulate an act of self-reflection that generates a process of self-transformation that is continuous, non-normative, and non-teleological.
The tomato is the model species of choice for fleshy fruit development and for the Solanaceae family. Ethyl methanesulfonate (EMS) mutants of tomato have already proven their utility for analysis of ...gene function in plants, leading to improved breeding stocks and superior tomato varieties. However, until recently, the identification of causal mutations that underlie particular phenotypes has been a very lengthy task that many laboratories could not afford because of spatial and technical limitations. Here, we describe a simple protocol for identifying causal mutations in tomato using a mapping-by-sequencing strategy. Plants displaying phenotypes of interest are first isolated by screening an EMS mutant collection generated in the miniature cultivar Micro-Tom. A recombinant F
population is then produced by crossing the mutant with a wild-type (WT; non-mutagenized) genotype, and F
segregants displaying the same phenotype are subsequently pooled. Finally, whole-genome sequencing and analysis of allele distributions in the pools allow for the identification of the causal mutation. The whole process, from the isolation of the tomato mutant to the identification of the causal mutation, takes 6-12 months. This strategy overcomes many previous limitations, is simple to use and can be applied in most laboratories with limited facilities for plant culture and genotyping.
L-Galactono-1,4-lactone dehydrogenase (EC 1.3.2.3) catalyzes the last step in the main pathway of vitamin C (L-ascorbic acid) biosynthesis in higher plants. In this study, we first characterized the ...spatial and temporal expression of SlGalLDH in several organs of tomato (Solanum lycopersicum) plants in parallel with the ascorbate content. P₃₅S:SlgalldhRNAi silenced transgenic tomato lines were then generated using an RNAi strategy to evaluate the effect of any resulting modification of the ascorbate pool on plant and fruit development. In all P₃₅S:SlgalldhRNAi plants with reduced SlGalLDH transcript and activity, plant growth rate was decreased. Plants displaying the most severe effects (dwarf plants with no fruit) were excluded from further analysis. The most affected lines studied exhibited up to an 80% reduction in SlGalLDH activity and showed a strong reduction in leaf and fruit size, mainly as a consequence of reduced cell expansion. This was accompanied by significant changes in mitochondrial function and altered ascorbate redox state despite the fact that the total ascorbate content remained unchanged. By using a combination of transcriptomic and metabolomic approaches, we further demonstrated that several primary, like the tricarboxylic acid cycle, as well as secondary metabolic pathways related to stress response were modified in leaves and fruit of P₃₅S:SlgalldhRNAi plants. When taken together, this work confirms the complexity of ascorbate regulation and its link with plant metabolism. Moreover, it strongly suggests that, in addition to ascorbate synthesis, GalLDH could play an important role in the regulation of cell growth-related processes in plants.
Key mechanisms controlling fruit weight and shape at the levels of meristem, ovary or very young fruit have already been identified using natural tomato diversity. We reasoned that new developmental ...modules prominent at later stages of fruit growth could be discovered by using new genetic and phenotypic diversity generated by saturated mutagenesis. Twelve fruit weight and tissue morphology mutants likely affected in late fruit growth were selected among thousands of fruit size and shape EMS mutants available in our tomato EMS mutant collection. Their thorough characterization at organ, tissue and cellular levels revealed two major clusters controlling fruit growth and tissue morphogenesis either through (i) the growth of all fruit tissues through isotropic cell expansion or (ii) only the growth of the pericarp through anisotropic cell expansion. These likely correspond to new cell expansion modules controlling fruit growth and tissue morphogenesis in tomato. Our study therefore opens the way for the identification of new gene regulatory networks controlling tomato fruit growth and morphology.
This article examines the relationship betweenminimalist storytellingandliterary representation. In the case ofMarguerite Duras's
Hiroshima mon amour
, the author shows that the preference for simple ...sentences, ellipsis, and parataxis over elaborate syntactic structures is not adverse to representation. The technique of foregrounding absences, silences, and the resistance of reality to being captured in a positively given content and form engages readers in reflection on the intricacies of representing reality. By staging a breakdown in depicting Hiroshima, Duras's text is designed to draw attention to its mechanism ofdisplacement, thereby exposing its failure to represent the ongoingwarinAlgeria.
Micro-Tom tomato cultivar is particularly adapted to the development of genomic approaches in tomato. Here, we describe the culture of this plant in greenhouse, including climate regulation, seed ...sowing and watering, vegetative development, plant maintenance, including treatment of phytosanitary problems, and reproductive development.
Critics often note the similarity between the short stories of Anton Chekhov, Ernest Hemingway, and Raymond Carver, citing their uneventful plots, fragmented character portraits, and lack of ...epiphanies and other narrative tools of compensating for their understated representation and anticlimactic endings. Some even regard them as stories about nothing—too sparse and open ended to be well-rounded literary narratives. This study compares the use of understatement and anticlimax by Chekhov, Hemingway, and Carver. It argues that each writer develops a unique version of understated and anticlimactic storytelling that endows the purported nullity of his stories with a distinctive meaning by accentuating his created literary world. These worlds and how they are produced form a countertradition to that of modernist so-called “impressionist” tales.
The cell expansion phase contributes in determining the major characteristics of a fleshy fruit and represents two-thirds of the total fruit development in tomato (Solanum lycopersicum). So far, it ...has received very little attention. To evaluate the interest of a genomic scale approach, we performed an initial sequencing of approximately 1,200 cell expansion stage-related sequence tags from tomato fruit at 8, 12, and 15 d post anthesis. Interestingly, up to approximately 35% of the expressed sequence tags showed no homology with available tomato expressed sequence tags and up to approximately 21% with any known gene. Microarrays spotted with expansion phase-related cDNAs and other fruit cDNAs involved in various developmental processes were used (1) to profile gene expression in developing fruit and other plant organs and (2) to compare two growing fruit tissues engaged mostly in cell division (exocarp) or in cell expansion (locular tissue surrounding the seeds). Reverse transcription-polymerase chain reaction analysis was further used to confirm microarray results and to specify expression profiles of selected genes (24) in various tissues from expanding fruit. The wide range of genes expressed in the exocarp is consistent with a protective function and with a high metabolic activity of this tissue. In addition, our data show that the expansion of locular cells is concomitant with the expression of genes controlling water flow, organic acid synthesis, sugar storage, and photosynthesis and suggest that hormones (auxin and gibberellin) regulate this process. The data presented provide a basis for tissue-specific analyses of gene function in growing tomato fruit.
•NaHCO3 a natural contaminant in irrigation underground water impairs tomato plants.•Hydroponic solutions containing above 5 mM NaHCO3 decreased tomato yield.•K+/Na+ ratio, whole biomass, fruit ...number and weight decreased by NaHCO3 treatment.•NaHCO3 impacts photosynthesis primarily through stomatal closure.•Ascorbic acid deficient mutants show similar damage as wild type plants under stress.
Underground water enriched in NaHCO3 is used in farms of the Buenos Aires province for tomato crop irrigation. This farming practice leads to salt accumulation and soil impairment after several seasons of cultivation inside the greenhouses. This work assayed the effect of NaHCO3 on tomato fruit production. Plants of the Elpida variety of Solanum lycopersicum L were grown in a hydroponic system. The presence of NaHCO3 (from 5 mM, as measured in the underground water to 10 or 20 mM) reduced K+/Na+ ratio and whole plant biomass and fruit yield; however, no effect was observed on fruit quality parameters. To test the participation of ascorbic acid in the tolerance to this stress, two slggp1 Micro-Tom mutant lines deficient in this antioxidant were used. In these experiments plants were treated with 0, 5 and 10 mM NaHCO3 causing an impairment of K+/Na+ ratio, photosynthesis, fruit yield, leaf and shoot dry weight (but without effect in root biomass) and delaying of fruit ripening time. Wild type and mutants plant responses showed no differences at stress conditions. Although NaHCO3 treatments caused a similar impairment in ascorbic acid mutants and wild type plants, these results reinforced the physiological importance of ascorbic acid levels to optimize plant growth under non-stressful conditions. Taken as a whole, the results presented here demonstrated the importance of avoiding the accumulation of this salt in greenhouse soils to optimize tomato production.
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