Mild Drought Stress‐Induced Changes in Yield, Physiological Processes and Chemical Composition in Festuca, Lolium and Festulolium

Abstract

The impact of mild drought stress (3 weeks at 40 % field water capacity) on yield, physiological processes, accumulation of proline and phenolic compounds and forage quality parameters in forage grasses was evaluated in pot experiments. During four different growing periods, the effects of water deficit were assessed in nine varieties from five species (Lolium perenne, Lolium multiflorum, Festuca pratensis, Festuca arundinacea and Festulolium braunii). All measured parameters were affected by drought stress in the different cuts. Photosynthesis, transpiration rate, stomatal conductance and dry matter yield were significantly lower in drought stress than under well-watered conditions in all varieties. Higher wateruse efficiency was only observed during the first and fourth drought period, while this was not the case in the second and third. Mild drought stress significantly increased the content of proline, phenolic acid, flavonoids, water-soluble carbohydrates and protein. All tested grasses showed also an increase of organic matter digestibility and cell wall digestibility under drought stress conditions.

Morphological, physiological and anatomical traits of plant functional types in temperate grasslands along a large-scale aridity gradient in northeastern China

“…There has been a great deal of research showing that free proline and soluble sugar accumulation in plants are the crucial osmotic adjustment processes to adapt to aridity, including both short-term and long-term stresses3839. Proline and soluble sugar accumulation enables cells to maintain turgor, thus allowing high water content levels to be sustained whilst cell osmotic potential decreases under water deficient conditions1144041.…”

How can forage production in Nordic and Mediterranean Europe adapt to the challenges and opportunities arising from climate change?

“…For timothy, the priorities would likely be to improve tolerance to harvesting and grazing, better regrowth capacity and spring growth. Perennial ryegrass needs better winter survival, particularly improved timing of growth cessation and cold acclimation, as well as resistance to psycrophilic pathogenic fungi (Abdelhalim et al, 2016), while for tall fescue, work is ongoing to combine the high yield and drought tolerance with an acceptable digestibility and animal preference (Humphreys et al, 2012;Helgadóttir et al, 2014;Cougnon et al, 2015;Fariaszewska et al, 2016).…”

Impacts of abiotic stresses on the physiology and metabolism of cool‐season grasses: A review

“…Significant increases in total non‐structural carbohydrates under conditions of limited water supply have been reported in several cool‐season grass species (Busso et al. 1990; Huang & Fu, ; Huang et al., ; Huang & Gao, 2000a; Da Costa & Huang, ; Fariaszewska et al., ). Thomas () in studies with perennial ryegrass under drought stress conditions, remarked on the differential pattern observed between leaves and bases, with the latter containing substantially more carbohydrates.…”

“…Fariaszewska et al. () observed substantial increases in proline content of meadow fescue under conditions of mild drought stress, whereas in tall fescue, leaf proline content was increased under both mild and severe water‐deficit stress (Ebrahimiyan et al., ). Sarmast et al.…”