Effects of two water regimes on morphological traits, nutritive value and physiology of three Bituminaria bituminosa varieties from the Canary Islands

Abstract

Morphological traits, nutritive values and physiological responses to two different water regimes of three Bituminaria bituminosa varieties: var. albomarginata, var. crassiuscula and var. bituminosa were evaluated in a greenhouse experiment. Two water regimes were imposed for 63 days; well‐watered (WW) plants and deficit‐watered (DW) plants, both starting from a high soil water content (dripping point). The three varieties showed similar aerial biomass reduction under reduced watering, 50% for var. albomarginata, 51% for var. bituminosa and 43% for var. crassiuscula. Var. Albomarginata showed lower shoot biomass under both water regimes than var. bituminosa (56.2% in WW plants and 55.2% in DW plants) and var. crassiuscula (52% in WW plants and 57.8% in DW plants). This lower shoot biomass could be attributed to the high initial soil water content imposed in this experiment, affecting early development. This hypothesis is supported by the lower root biomass production of var. albomarginata and its distribution. The DW treatment of this experiment was not sufficiently restrictive to cause morphological modifications, whilst of the forage quality variables analysed, only ash was affected. Var. crassiuscula and var. albomarginata had a lower specific leaf area (239 cm2 g‐1 and 235 cm2 g‐1, respectively) than var. bituminosa (352 cm2 g‐1), which might represent an important adaptation to high light intensity and temperature conditions. The values of stem mass fraction (SMF) and leaf mass fraction (LMF) for var. crassiuscula (SMF = 0.36 and LMF = 0.28) and var. albomarginata (SMF = 0.35 and LMF = 0.36) indicated better forage aptitude of these varieties than var. bituminosa (SMF = 0.50 and LMF = 0.19). All varieties showed good values of crude protein and digestibility, although important differences were found between leaf and stem. According to the studied morphological, nutritional and physiological traits, var. albomarginata showed the best aptitude for being introduced as permanent grasslands in some Mediterranean farming systems. However, the possible susceptibility of var. albomarginata to high water content in the soil could limit its introduction. These results help to inform the potential use of these three Canarian B. bituminosa varieties to improve Mediterranean rainfed grasslands of extensive farming systems.

Short‐term drought is a stronger driver of plant morphology and nutritional composition than warming in two common pasture species

“…Both of these outcomes pose an increased climate risk to the dairy and meat industries (Perera et al., 2020; Rojas‐Downing et al., 2017). Along with changes in pasture productivity, there are also potential shifts in the morphological traits and nutritional composition of pasture species that are likely to alter forage quality and digestibility (AbdElgawad et al., 2014; Fernández‐Habas et al., 2021; Herrero et al., 2015; Howden et al., 2008). In contrast to shifts in productivity, these changes and their consequences under future climate scenarios, such as warming and drought, are relatively understudied.…”

Multi‐species for multifunctional grassland: Evaluation of minor and novel forage species for temperate humid grasslands

“…B. bituminosa is a widely used forage species on the Canary Islands and accessions are therefore adapted to a huge gradient of rainfall. In studies, its adaptation to drought conditions has been confirmed along with high forage provision potential (e.g., Fernández‐Habas et al, 2021; Méndez et al, 1991). Depending on the variety, B. bituminosa exhibits both drought tolerance and cold tolerance.…”

LANZA® Tedera Is Strongly Suppressed by Competition from Lolium multiflorum and Is Best Adapted to Light-Textured Soils

“…Clay soil has two-fold the water content of loamy sand soil at saturation (Table 1). Fernández-Habas et al [18] pointed out that the root system development of B. bituminosa var albomarginata could be negatively affected by high soil water content in soils with elevated soil water retention capacity such as clay/silty soils, which could explain the reduction in thin root dry mass of plants grown in clay soil. Differences in soil P content could also affect root biomass [70,71].…”

“…albomarginata from the Canary Islands, where it is known by the common name Tedera [14]. Previous research has demonstrated that this species is productive under very low rainfall (<200 mm), is highly drought-resistant [15][16][17], has good forage quality [18][19][20], and it is suitable for feeding livestock [14,[21][22][23]. Recently, an improved variety has been developed as a result of a collaborative breeding programme led by Australian and Spanish researchers [9].…”

“…Previous research suggested that soil water saturation could be unfavourable for B. bituminosa var. albomarginata [18] and that it is unlikely to persist in environments with cold wet winters [28]. Real et al [9] found B. bituminosa to be sensitive to waterlogging overall, although it showed high variability in waterlogging tolerance.…”