title: The efficient physiological strategy of a tomato landrace in response to short-term salinity stress.
abstract: Landraces represent an important part of the biodiversity well-adapted under limiting environmental conditions. We investigated the response of two Southern Italy tomato landraces, the well-known San Marzano (our commercial standard) and a local accession called "Ciettaicale", to different levels of sodium chloride in water irrigation (from 0 up to 600 mM) for a short-time exposure (one week). The combination of the chlorophyll a fluorescence and gas exchange analyses suggested that Ciettaicale maintained a higher efficiency of photosystem II (PSII) photochemistry and CO2utilization at high salinity concentrations than San Marzano. Stomatal and non-stomatal limitations occurred in San Marzano according to the reduction of maximum efficiency of PSII photochemistry and the increase of intercellular CO2concentration. Higher Na+/K+ratio and higher concentration of total soluble sugars contributed to non-stomatal limitations in San Marzano leaves. These effects were significantly less evident in Ciettaicale. We also observed changes in total antioxidant capacity and leaf pigment content that emphasized the occurrence of modifications in the photosynthetic apparatus according to salt gradient. The more efficient assimilates supply and an integrated root protection system provided by sugars and antioxidants can explain the significantly higher root/shoot ratio in Ciettaicale. Overall, our results suggest that a comprehensive assessment of salinity tolerance in a genotypes comparison could be also obtained evaluating plant response to high salinity levels at early vegetative stage. In addition, further studies will be carried out in order to evaluate the possibility of using Ciettaicale in tomato improvement programs.
authors: Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy.
authors: Tommaso Michele
authors: TM
authors: Moles
authors: Laboratory of Ecological Plant Physiology, Global Change Research Institute CAS, Brno, Czech Republic.
authors: Antonio
authors: A
authors: Pompeiano
authors: Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy.
authors: Thais
authors: T
authors: Huarancca Reyes
authors: Institute of Agro-environmental and Forest Biology, National Research Council, Monterotondo Scalo, RM, Italy.
authors: Andrea
authors: A
authors: Scartazza
authors: Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy; Interdepartmental Research Center Nutrafood-Nutraceuticals and Food for Health, University of Pisa, Pisa, Italy. Electronic address: lorenzo.guglielminetti@unipi.it.
authors: Lorenzo
authors: L
authors: Guglielminetti
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D000975:Antioxidants / Q000378:metabolism; D044822:Biodiversity; D050260:Carbohydrate Metabolism; D002245:Carbon Dioxide / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D002980:Climate; D007558:Italy; D018551:Solanum lycopersicum / Q000145:classification / Q000235:genetics / Q000502:physiology*; D019083:Mediterranean Region; D010788:Photosynthesis; D054712:Salinity; D055049:Salt Tolerance / Q000235:genetics / Q000502:physiology*; D013045:Species Specificity; D013312:Stress, Physiological
chemical_list: D000975:Antioxidants; D002734:Chlorophyll; D002245:Carbon Dioxide; D000077194:Chlorophyll A
keywords: Antioxidants; Chlorophyll a fluorescence; Gas exchange; Salt tolerance; Soluble sugars; Tomato landrace