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Ferrari, R. C.

Publications and source records attributed to Ferrari, R. C..

2 recordsLinked to original sources

Differential modulation of crassulacean acid metabolism according to macronutrient deficiencies in C4 Portulaca oleracea

O_LIC4 photosynthesis and the crassulacean acid metabolism (CAM) rarely co-evolved in a single lineage, but Portulaca can switch from C4 to CAM under drought stress. Little is known about CAM responses to nutrient availability, hence the goal of this work was to assess the influence of macronutrients over C4-CAM. C_LIO_LIP. oleracea was grown hydroponically and subjected to treatments (+/- PEG) for: nitrate deficiency (-NO3-), ammonium (NH4+), NO3- + NH4+, magnesium (-Mg), phosphorus (-P), calcium (-Ca), potassium (-K), and sulphur (-S) deficiencies, and salt stress. Samples were monitored for diurnal titratable acidity ({Delta}H+), osmotic potential, and gene relative expression for core C4/CAM and signaling genes. C_LIO_LI-NO3- induced CAM even without PEG, a process probably without the mediation of abscisic acid (ABA). Notably, -P showed a trend to induce CAM without PEG and -Ca prevented CAM induction even with PEG. Salt stress induced CAM, and NH4+ was not toxic for P. oleracea. Other treatments showed less conspicuous responses. C_LIO_LIThis work brings an unprecedented overview of the nutrition of C4 and CAM, suggesting perspectives for deepening the study of C4-CAM. Understanding the molecular mechanisms and environmental signaling of C4-CAM is essential for realizing the evolution of two CCMs in a single plant. C_LI

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↗