Discerning morpho-anatomical, physiological and molecular multiformity in cultivated and wild genotypes of lentil with reconciliation to salinity stress

Abstract

One hundred and sixty two genotypes of different Lens species were screened for salinity tolerance in hydroponics at 40, 80 and 120 mM sodium chloride (NaCl) for 30 d. The germination, seedling growth, biomass accumulation, seedling survivability, salinity scores, root and shoot anatomy, sodium ion (Na+), chloride ion (Cl-) and potassium ion (K+) concentrations, proline and antioxidant activities were measured to evaluate the performance of all the genotypes. The results were compared in respect of physiological (Na+, K+ and Cl-) and seed yield components obtained from field trials for salinity stress conducted during two years. Expression of salt tolerance in hydroponics was found to be reliable indicator for similarity in salt tolerance between genotypes and was evident in saline soil based comparisons. Impressive genotypic variation for salinity tolerance was observed among the genotypes screened under hydroponic and saline field conditions. Plant concentrations of Na+ and Cl- at 120 mM NaCl were found significantly correlated with germination, root and shoot length, fresh and dry weight of roots and shoots, seedling survivability, salinity scores and K+ under controlled conditions and ranked the genotypes along with their seed yield in the field. Root and shoot anatomy of tolerant line (PDL-1) and wild accession (ILWL-137) showed restricted uptake of Na+ and Cl- due to thick layer of their epidermis and endodermis as compared to sensitive cultigen (L-4076). All the genotypes were scanned using SSR markers for genetic diversity, which generated high polymorphism. On the basis of cluster analysis and population structure the contrasting genotypes were grouped into different classes. These markers may further be tested to explore their potential in marker-assisted selection.

Evaluation of cultivated and wild genotypes of Lens species under alkalinity stress and their molecular collocation using microsatellite markers

“…Intact pericycle and steler region of tolerant genotypes also helped in reducing the ion absorption. Similar observations were also made in lentil [ 36 ], finger millet [ 23 ] and Lotus tenuis [ 11 ]. Similarly, the shoot had thick epidermis in tolerant genotypes compared sensitive ones.…”

“…This trait has been widely used parameter for selecting salt-tolerant lines and cultivars [ 35 ]. Breeding for seedling survival and vigorous growth has been argued to be agronomically most effective approach for increasing yield under saline soils [ 36 ]. Alkalinity stress at 40 mM NaHCO 3 had affected the seedling survival in all the genotypes.…”

Potential and limits of exploitation of crop wild relatives for pea, lentil, and chickpea improvement

“…Screening of 100 accessions of L. culinaris subsp. orientalis under hydroponic culture at 120‐mM NaCl concentration resulted in the identification of several donors for salinity tolerance (Singh et al, 2017). Importantly, flowering and growth responses of wild Lens to light quality have also been studied (Yuan, Saha, Vandenberg, & Bett, 2017).…”

Genetics and molecular mapping for salinity stress tolerance at seedling stage in lentil (Lens culinarisMedik)

“…Earlier studies have indicated that the lentil crop is sensitive to salinity stress (Ashraf & Waheed, 1990). Significant genetic variation for salinity tolerance prevails among the genotypes of lentil (Singh et al., 2017). The development of saline tolerant cultivars can be an appropriate approach for minimizing yield losses under salinity stress conditions.…”

“…Various physiological and biochemical traits like seedling survivability, salinity score, seedling growth and biomass, Na + and Cl − accumulation, production of H 2 O 2, antioxidant activities etc. have been used for characterization of salinity tolerance at the seedling stage in crop plants (Singh et al., 2017; Singh et al., 2018a; Singh et al., 2018b). Among the above traits, seedling survivability and FDA based fluorescent signals (indicating production of H 2 O 2 ) are the major traits to visually distinguish between salt‐tolerant and salt‐sensitive genotypes (Singh et al., 2017).…”