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Zsögön, A.

Publications and source records attributed to Zsögön, A..

5 recordsLinked to original sources

SELF PRUNING 3C is a flowering repressor that modulates seed germination, root architecture and drought responses

Allelic variation in the CETS (CENTRORADIALIS, TERMINAL FLOWER 1, SELF PRUNING) gene family has been shown to control agronomically important traits in many crops. CETS genes encode phosphatidylethanolamine binding proteins (PEBPs) that have a central role in flowering time control as florigenic and anti-florigenic signals. The great expansion of CETS genes in many species suggests that the functions of this family go beyond flowering. Here, we characterize the tomato SELF PRUNING 3C (SP3C) gene, and show that besides acting as a flowering repressor it also regulates seed germination and modulates root architecture. We show that loss of SP3C function in CRISPR/Cas9-generated mutant lines accelerates seed germination and increases root length with lower root side branching. Higher SP3C expression in transgenic lines promotes the opposite effects and also improves tolerance to water stress in seedlings. These discoveries provide insights into the role of SP paralogs in agronomically relevant traits and support future exploration of the involvement of CETS genes in abiotic stress responses. HighlightThe SELF PRUNING 3C (SP3C) gene is a repressor of flowering in tomato and exhibits additional functions, acting as a repressor of seed germination and modulating root architecture.

molecular biology↗

Hotter chili peppers by hybridisation: heterosis and reciprocal effects

The selection of pure lines followed by crosses to create superior hybrids is one of the oldest strategies in crop breeding. However, in domesticated species of the Capsicum genus hybrid breeding has lagged, in part due to a lack of detailed information about the phenotypic and metabolic consequences of hybridization. Here, we performed reciprocal crosses between four inbred varieties of two species of cultivated C. chinense (cv. Habanero and Biquinho) and C. annuum var. annuum (cv. Jalapeno and cv. Cascadura Ikeda). These varieties were specifically selected for their highly divergent traits, including plant growth habit, fruit size, shape and pungency: Habanero and Jalapeno peppers are highly pungent forms, particularly popular in Mexico. The Biquinho cultivar of C. chinense and the Cascadura Ikeda bell pepper are traditional sweet cultivars from Brazil. From the parental genotypes and from the progeny of the reciprocal crosses, we measured 28 phenotypic traits, including plant growth, and yield, 32 fruit shape parameters, and 50 fruit pericarp and placenta metabolites, including capsaicinoids. We found large differences for agronomic and metabolic traits between the genotypes, including heterosis for pungency and reciprocal effects for agronomic traits. We also show that the strong association between fruit shape and pungency can be broken in intraspecific hybrids, paving the way for the precision breeding of novel varieties. Once sentence summaryHybrids of Capsicum peppers display heterosis and reciprocal effects for agronomic traits and fruit pungency

plant biology↗

Elevated CO2 induces age-dependent restoration of growth and metabolism in gibberellin-deficient plants

Main conclusion The effect of elevated [CO2] on the growth of tomato plants with reduced GA content is influenced by developmental stage. The increase of carbon dioxide (CO2) in the atmosphere during the last decades has aroused interest in the function of this gas in the growth and development of plants. Despite the known association between elevated CO2 concentration ([CO2]) and plant growth, its effects in association with gibberellin (GA), plant hormone that regulates de major aspects of plant growth, are still poorly understood. Therefore, we evaluated the effect of elevated [CO2] on growth and primary metabolism in tomato plants with drastic reduction in GA content (gib-1) at two different growth stages (21 and 35 days after germination, dag). Disruption on growth, photosynthetic parameters and primary metabolism were restored when gib-1 plants were transferred to elevated [CO2] at 21 dag. Elevated [CO2] also stimulated growth and photosynthetic parameters in Wild type (WT) plants at 21 dag, however, minor changes were observed in the level of primary metabolites. At 35 dag, elevated [CO2] did not stimulate growth in WT plants and gib-1 mutants showed their characteristic stunted growth phenotype.

plant biology↗

SELF-PRUNING affects auxin responses synergistically with the cyclophilin A DIAGEOTROPICA in tomato

SummaryThe antiflorigenic signal SELF-PRUNING, which controls growth habit, exerts its effects through auxin transport, signaling and metabolism in tomato.\n\nAbstractThe SELF PRUNING (SP) gene is a key regulator of growth habit in tomato (Solanum lycopersicum). It is an ortholog of TERMINAL FLOWER 1, a phosphatidyl-ethanolamine binding protein with anti-florigenic activity in Arabidopsis thaliana. A spontaneous loss-of-function sp mutation has been bred into a large number of industrial tomato cultivars, as it produces a suite of pleiotropic effects that are favorable for mechanical harvesting, including determinate growth habit, short plant stature and simultaneous fruit ripening. However, the physiological basis for these phenotypic differences has not been thoroughly explained. Here, we show that the sp mutation alters polar auxin transport as well as auxin responses such gravitropic curvature and elongation of excised hypocotyl segments. We further demonstrate that free auxin levels and auxin-regulated gene expression patterns are altered in sp, with epistatic effects of diageotropica, a mutation in a cyclophilin A protein-encoding gene. Our results indicate that SP impacts growth habit in tomato, at least in part, via changes in auxin transport and responsiveness. These findings hint at novel targets that could be manipulated in the control of growth habit and productivity.

plant biology↗

Bundle sheath extensions in tomato affect leaf phenotypic plasticity in response to irradiance

Coordination between structural and physiological traits is key to plants responses to environmental fluctuations. In heterobaric leaves, bundle sheath extensions (BSEs) increase photosynthetic performance (light-saturated rates of photosynthesis, Amax) and water transport capacity (leaf hydraulic conductance, Kleaf). However, it is not clear how BSEs affect these and other leaf developmental and physiological parameters in response to environmental conditions. The obscuravenosa (obv) mutation, found in many commercial tomato varieties, leads to absence of BSEs. We examined structural and physiological traits of tomato heterobaric and homobaric (obv) near-isogenic lines (NILs) grown at two different irradiance levels. Kleaf, minor vein density and stomatal pore area index decreased with shading in heterobaric but not in homobaric leaves, which show similarly lower values in both conditions. Homobaric plants, on the other hand, showed increased Amax, leaf intercellular air spaces and mesophyll surface area exposed to intercellular airspace (Smes) in comparison with heterobaric plants when both were grown in the shade. BSEs further affected carbon isotope discrimination, a proxy for long-term water-use efficiency. BSEs confer plasticity in traits related to leaf structure and function in response to irradiance levels and might act as a hub integrating leaf structure, photosynthetic function and water supply and demand.\n\nSummary statementThe presence of bundle sheath extension (BSEs) defines leaves as heterobaric, as opposed to homobaric leaves that lack them. Multiple functions have been proposed for BSEs, but their impact on different environmental conditions is still unclear. Here, we compared a tomato (Solanum lycopersicum) homobaric mutant lacking BSEs with its corresponding heterobaric wild-type, grown under two irradiance conditions. We show that the presence of BSEs differentially alters various physiological and anatomical parameters in response to growth irradiance. We propose that BSEs could act as hubs coordinating leaf plasticity in response to environmental factors.\n\nArticle typeResearch article

plant biology↗