Variability in tolerance and recovery from waterlogging, salinity, and their combination among Festuca arundinacea cultivars

MENON MARTINEZ FE; GRIMOLDI AA; STRIKER GG; DI BELLA CE

Crop and Pasture Science

CSIRO Publishing

Año: 2021 vol. 72 p. 75 - 84

1836-0947

Frequency and intensity of floods and the extent of salt-affected lands are both expected to increase in pastures and grassland ecosystems as a result of global climate change. This study evaluated the effects of waterlogging (W), salinity (S; 150 mM NaCl, ≈ 15 dS m-1) and their combination (WS) over 14 days (treatment phase) on morphological and growth traits of seven Festuca arundinacea cultivars. A 14-day growth period under control conditions (aerated ? non-saline) was allowed to assess recovery (recovery phase). Plant survival was not compromised in any cultivar by either stress, being the tolerance to W higher than to S and WS. The combined stress provoked lower growth than predicted by the multiplicative model in one cultivar, equal in three and higher in three cultivars. High variability among cultivars in response to each stress and phase was observed, which was more evident for root?s relative growth rate (RGR) than for shoot?s RGR. Plant morphological traits were affected by treatments in different ways: mature tiller weight was maintained, and tiller number decreased by 79-71% under W and WS, while opposite responses occurred under S treatment. During the recovery phase, plants of all treatments reduced tiller number compared to controls and prioritized the growth of pre-existing tillers, which were heavier. Dead leaves per plant increased in both saline treatments. In general, F. arundinacea proved to be more tolerant to waterlogging than to salinity (W vs. S or WS), showing promising variability among cultivars in root RGR responses under the evaluated stresses, which can be useful in future breeding plans.