Differential response of Trichloris ecotypes from different habitats to drought and salt stress

Abstract

Native plant genetic resources have evolved from long processes of natural selection and adaptation to specific environments, and have developed tolerance to various stresses prevailing in their natural habitats via adaptive morphophysiological features. The associations between environmental stress conditions (aridity degree and salinity) prevailing in the original habitat of Argentine native Trichloris species (T. crinita and T. pluriflora) and various biometric and physiological traits were evaluated. Trials were carried out in hydroponics in a growth chamber. Components of initial plant growth, oxidative stress expression and antioxidant activity under drought and salt stress were measured in ecotypes of both species, as well as Na ? and K ? leaf tissue concentration and excretion rates under salinity. Ecotypes from arid and semiarid origin of both species had higher drought tolerance. Regarding salt stress, T. crinita ecotype from alkali soil showed stimulated growth under salinity and an ecotype from saline soil kept high root and shoot biomass production. Although the ecotypes of T. pluriflora were not significantly salt-sensitive, none stood out. Many active salt glands on the abaxial leaf surface, high Na/K excretion ratio and high leaf tissue concentration of sodium were found for salt-tolerant ecotypes. This study identified ecotypes with tolerance to prevailing stressful conditions of natural habitat of native forage species to be introduced to plant breeding programmes for restorations purposes. Trichloris pluriflora is an unexplored genetic resource for semiarid rangeland, thus this study is the first report of drought tolerant ecotypes.

Spatiotemporal seed transfer zones as an efficient restoration strategy in response to climate change

“…Here we performed a cluster analysis separately for each component (i.e., bioclimatic, edaphic, and geophysical), which allowed us to find the optimal set of variables that defines the real structure of the underlying groups (Raftery and Dean 2006, Dean et al 2018) and a balanced contribution for each component. This is particularly important in both Trichloris species, since geophysical and bioclimatic factors have been associated with adaptive genetic variation in seed weight, a critical trait of plant's life history related to fitness across plant species (Marinoni et al 2018) as well as with adaptive traits associated with tolerance to water and salt stress (Marinoni et al 2020).…”

“…geophysical and bioclimatic factors have been associated with adaptive genetic variation in seed weight, a critical trait of plant's life history related to fitness across plant species (Marinoni et al 2018) as well as with adaptive traits associated with tolerance to water and salt stress (Marinoni et al 2020).…”

“…Parodi, and T. pluriflora E. Fourn are C4 perennial grasses with a disjunct distribution in Argentine and USA rangelands (Lloyd‐Reilley 2011, Quiroga et al 2018). Both species are highly autogamous (Gutiérrez et al 2016, Kozub et al 2017), and they are distributed in semiarid rangelands, but only T. crinita grows in arid (150 mm of annual rainfall) and saline environments (Rúgolo and Molina 2012, Marinoni et al 2015, 2020). Although both species have good forage quality for livestock production in arid and semiarid rangelands (Kunst et al 1995, Quiroga et al 2013, Kozub et al 2018 b ), T. crinita has been more studied because of its tolerance to extreme environmental conditions.…”

Seed Weight and Trade-Offs: An Experiment in False Rhodes Grasses under Different Aridity Conditions

“…Both species are warm-season perennial bunchgrasses [ 22 ]. Leptochloa crinita has been widely studied for restoration purposes because of its broad distribution and tolerance to extreme aridity and salinity conditions [ 6 , 15 , 23 , 24 , 25 , 26 , 27 ], whereas L. pluriflora has been less explored [ 25 , 26 , 27 ]. In a previous study involving populations from the entire distribution range of L. crinita in Argentina, cultivated in a common-garden experiment, we observed an important additive genetic component for seed weight and signs of local adaptation [ 26 ].…”

Exogenous 5-azaCitidine accelerates flowering and external GA3 increases ornamental value in Iranian Anemone accessions

“…Wild species are important genetic resources since they can carry genes responsible for further improvement in various ornamental traits and tolerance to various biotic and abiotic stresses 36 . In addition, the identification of promising native plant genetic resources for domestication purposes requires long-term plans for collection, conservation, and characterization 38 . Accordingly, genetic diversity is an important component of conservation biodiversity 39 .…”