Timing of drought in the growing season

• Main Author: Hahn, Claudia
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2020
• Subjects: Beluga; Beluga*
• Online Access: https://doi.org/10.5281/zenodo.4306840

Experimental setup: For the experiment we established six grasses in monoculture that are commonly used in agricultural practice in August 2013 on 168 plots (3 × 5 m). This timing is following best practice and guarantees full establishment of the sward (including vernalisation during winter) and full productivity in the following year. The six grasses established were Lolium perenne L. early flowering (LPe; cultivar ‘Artesia’), Lolium perenne L. late flowering (LPl; cultivar ‘Elgon’), Dactylis glomerata L. early flowering (DGe; cultivar ‘Barexcel’), Dactylis glomerata L. late flowering (DGl; cultivar ‘Beluga’), Lolium multiflorum Lam. var italicum Beck (LM; cultivar ‘Midas’), and Poa pratensis L. (PP; cultivar ‘Lato’). Phosphorous, potassium and manganese were applied following national fertilization recommendations for intensely managed grasslands at the beginning of each growing season (39 kg P/ha, 228 kg K/ha, 35 kg Mg/ha). In addition, all plots received the same amount of mineral N fertilizer as ammonium-nitrate (280 kg N/ha, divided into six applications per year). The solid N fertilizer was applied at the beginning of the growing season (80 kg N/ha) and after each of the first five cuts (40 kg N/ha each time). Each of the six grasses was subject to four treatments: one rain-fed control and three seasonal drought treatments (spring, summer, fall). A drought treatment lasted for ten weeks. Drought was simulated using rainout shelters that excluded rainfall completely on the treatment plots. The rainout shelters were tunnel-shaped and consisted of steel frames (3 × 5.5 m, height: 140 cm) that were covered with transparent and UV radiation transmissible greenhouse foil (Lumisol clear, 200 my, Hortuna AG, Winikon, Switzerland). To allow air circulation, shelters were open on both opposing short ends and had ventilation openings of 35 cm height over the entire length at the top and the bottom at both long sides. Rain-fed controls were subject to the natural precipitation regime. However, when soil water ...