Evaluation of Characters for Ascertaining Salt Stress Responses in Lycopersicon Species

Abstract

<jats:p>Plant height; stem thickness; fresh and dry weights of leaves and stems; numbers of leaves, trusses, flowers, and fruits; and leaf concentrations of Cl, Na, N-NO<jats:sub>3</jats:sub>, K, Ca, and Mg were measured in mature plants from 39 tomato accessions representing five species of <jats:italic>Lycopersicon [L. esculentum</jats:italic> Mill., <jats:italic>L. peruvianum</jats:italic> (L.) Mill., <jats:italic>L. pimpinellifoliurn</jats:italic> (Jusl.) Mill., <jats:italic>L. hirsutum</jats:italic> H. &amp; B., L. <jats:italic>pennellii</jats:italic> (Corr.) D'Arcy] in response to various NaCl concentrations. Plants were irrigated with a nutrient solution, plus one of four levels of NaCl with electrical conductivities of 0.28, 0.63, 1.39, and 2.15 S·m<jats:sup>-1</jats:sup>. Characters were evaluated for each genotype taking into consideration: 1) the significant differences between NaCl concentrations, 2) the experimental errors in the analyses of variance, and 3) the uniformity of response to the salt concentrations. The characters that fulfilled these criteria for all 39 genotypes were: plant height, dry weights of leaves, fresh and dry weights of stems, and leaf concentrations of Cl and Na. However, other characters, although not generally applicable to the entire data set, were good indicators of response differences within a particular species. Leaf concentrations of N-NO<jats:sub>3</jats:sub> and Mg were useful indicators in <jats:italic>L. pimpinellifolium</jats:italic> and <jats:italic>L. esculentum</jats:italic> and number of leaves and leaf concentration of Mg were useful indicators in <jats:italic>L. hirsutum</jats:italic> for responses of mature plants to salt stress.</jats:p>

Effects of NaCl salinity on miniature dwarf tomato ‘Micro‐Tom’: II. Shoot and root growth responses, fruit production, and osmotic adjustment1

“…The reduction of shoot expansion even at the 7.6 dS-m' 1 salt level contrasted observations on other tomato genotypes (Mitchell et al, 1991;Shannon et al, 1987), which have shown enhanced growth and yield under comparable saline conditions. In contrast to Cruz et al (1990), who found shoot length one of the most reliable response indicators for a wide range of tomato genotypes under saline stress, there was no consistent change in this parameter for 'Micro-Tom' as salinity levels increased. This lack of response is probably due to the highly compact growth habit of this selection.…”

“…Numerous criteria have been used to rank salinity tolerance of members of the genus Lycopersicon (including the cultivated tomato) (Hassan and Desouki, 1982;Sacher et al, 1983;Shannon et al, 1987;Tal and Shannon, 1983). Plants exhibit a complex range of responses and resistance to stress and standard measurement parameters for one genotype may not reflect tolerance of others (Cruz et al, 1990). In addition, environmental interference can mask important traits (Epstein, 1983;McCue and Hanson, 1990).…”

Agronomical and physiological characterization of salinity tolerance in a commercial tomato hybrid

“…The fruit yield reductions were due to both fruit weight and fruit number decreases in a similar proportion. Shoot development showed high reductions with salt all along the salinity range treated here; it is then a sensitive parameter to salt that could be used to evaluate salt tolerance in tomato (Cruz et al, 1990). However, the root biomass was very much less affected than the shoot and fruit yield under high salinity, indicating a preference of the root to the shoot growth as salinity increases between the range tried in this work.…”

Effect of salt stress on cucumber: Na+–K+ ratio, osmolyte concentration, phenols and chlorophyll content

“…The main reason for this being the complex nature of salt stress and the non-availability of simpler, quicker and reliable criteria for selection of tolerant types. Therefore, efforts were directed towards development of simpler and quicker systems and evaluation of traits that characterise salt stress responses (Cruz et al 1990). In our study, efforts were made to identify such traits.…”