Forage legumes for future dry climates: Lower relative biomass losses of minor forage legumes compared to Trifolium repens under conditions of periodic drought stress

Abstract

Dairy livestock production systems rely on high‐quality forage legumes, which are widely present in grassland swards all over Europe. A future climatic scenario with higher average annual temperatures and lower precipitation is expected to affect grassland productivity in general and the productivity of the most important forage legume species Trifolium repens in particular. One way to cope with such constraints is the adoption of currently underutilized minor legume species with a higher tolerance towards drought stress. Therefore, the present study investigated legume species with lower moisture requirements than T. repens, these are Lotus corniculatus, Medicago falcata, Medicago lupulina and Onobrychis viciifolia in comparison with T. repens. Legumes were grown in containers as monocultures in a roofed open‐sided greenhouse under conditions of optimal water supply or periodic drought stress. Generally, drought stress decreased the biomass production, but species differed in their reaction. Particularly, M. lupulina and L. corniculatus had lower relative biomass losses (−26%) compared to T. repens (−43%, as averaged over drought stress periods). However, in overall biomass production T. repens still was at one level with M. lupulina and L. corniculatus under drought stress. This was related to high stomata control as indicated by the intrinsic water‐use efficiency. We conclude that there are promising future options of forage legumes as alternatives to T. repens.

Crop Resilience to Drought With and Without Response Diversity

“…Our drought resistance experiment confirmed previous research (Döring et al, 2013;Storkey et al, 2015;Elsalahy et al, 2019;Komainda et al, 2019) that BM is more drought-resistant than AC. Relative to the maximum biomass potential, which was higher in AC than in BM, the biomass under constant drought conditions was similar in both species, so that the relative biomass-reducing effect of drought was stronger in AC than in BM (Figure 1A).…”

“…In both experiments, water use efficiency (WUE, in g DM L −1 ) was determined by using Equation (1) (Komainda et al, 2019).…”

“…Drought can affect crop yield directly or through complex interactions with soil properties, nutrient availability, and temperature stress (Mariotte et al, 2018) or with soil biota such as mycorrhiza (Schimel, 2018). Two scenarios of drought may affect crop production, cumulative drought stress (Swemmer et al, 2007;Navarro-Cerrillo et al, 2018), and periodic (transient) drought stress (Hofer et al, 2016;Komainda et al, 2019). While plants can withstand moderate changes in total annual precipitation, increased variability in the amount of precipitation per event and in the event duration can substantially impair aboveground biomass production (Swemmer et al, 2007).…”

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

“…A area and g Sarea values of BAM measured at day 46 (that was not the point of maximum drought stress) were associated with higher leaf RWC (Foster et al, 2015) which confirms the drought adaptation of this variety (Foster et al, 2013). In agreement with the results of this study, previous research has found little or no effect of moderate drought stress on the quality parameters of forage legumes (Komainda et al, 2019;Kuchenmeister, Kuchenmeister, Kayser, Wrage & Isselstein, 2013).…”

Effects of mixing two legume species at seedling stage under different environmental conditions

“…We chose alsike clover (AC; Trifolium hybridum L.) and black medic (BM; Medicago lupulina L.) and a 1:1 mixture of the two species as previous studies showed a positive mixture effect of these two species at this proportion regarding productivity, weed suppression, and resilience to drought ( Elsalahy et al, 2019 ; Elsalahy et al, 2020 ). BM is a fast-growing perennial well adapted to warm and dry areas ( Döring et al, 2013 ; Elsalahy et al, 2019 ; FAO, 2020 ; Komainda et al, 2019 ) with a base temperature of 0.6 °C and optimal germination temperature of 26 °C ( Tribouillois et al, 2016 ). Nonetheless, it was also reported for BM that the optimal range of temperatures lies between 10 °C and 20 °C ( Sharpe & Boyd, 2019 ).…”