Biomass production and water use efficiency in perennial grasses during and after drought stress

Sammanfattning

Drought is a great challenge to agricultural production, and cultivation of drought-tolerant or water use-efficient cultivars is important to ensure high biomass yields for bio-refining and bioenergy. Here, we evaluated drought tolerance of four C-3 species, Dactylis glomerata cvs. Sevenop and Amba, Festuca arundinacea cvs. Jordane and Kora, Phalaris arundinacea cvs. Bamse and Chieftain and Festulolium pabulare cv. Hykor, and two C-4 species Miscanthusxgiganteus and M.lutarioriparius. Control (irrigated) and drought-treated plants were grown on coarse and loamy sand in 1 m(2) lysimeter plots where rain was excluded. Drought periods started after harvest and lasted until 80% of available soil water had been used. Drought caused a decrease in dry matter yield (DM; P<0.001) for all species and cultivars during the drought period. Cultivars Sevenop, Kora and Jordane produced DM at equal levels and higher than the other C-3 cultivars in control and drought-treated plots both during and after the drought period. Negative correlations were observed between stomatal conductance (g(s)) and leaf water potential (P<0.01) and positive correlations between g(s) and DM (P<0.05) indicating that g(s) might be suitable for assessment of drought stress. There were indications of positive associations between plants carbon isotope composition and water use efficiency (WUE) as well as DM under well-watered conditions. Compared to control, drought-treated plots showed increased growth in the period after drought stress. Thus, the drought events did not affect total biomass production (DMtotal) of the whole growing season. During drought stress and the whole growing season, WUE was higher in drought-treated compared to control plots, so it seems possible to save water without loss of biomass. Across soil types, M.lutarioriparius had the highest DMtotal (15.0tha(-1)), WUEtotal (3.6gL(-1)) and radiation use efficiency (2.3gMJ(-1)) of the evaluated grasses.

Nyckelord

bioenergy; bio-refining; carbon isotopic composition; drought tolerance; dry matter yield; intercepted photosynthetically active radiation; leaf water potential; radiation use efficiency; ratio vegetation index; stomatal conductance

Publicerad i

Global Change Biology
2018, volym: 10, nummer: 1, sidor: 12-27

SLU författare

• Jensen, Erik Steen

  • Institutionen för biosystem och teknologi, Sveriges lantbruksuniversitet
    

• Dimitrova Mårtensson, Linda-Maria

  • Institutionen för biosystem och teknologi, Sveriges lantbruksuniversitet
    

Globala målen (SDG)

SDG7 Hållbar energi för alla
SDG12 Hållbar konsumtion och produktion

UKÄ forskningsämne

Annan biologi
Övriga andra lantbruksrelaterade vetenskaper
Botanik

Publikationens identifierare

• DOI: https://doi.org/10.1111/gcbb.12464

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/86287