32 sTERF ongoing projects
A comparison of the soil surfactant Qualibra and Revolution on creeping bentgrass greens varying in water availability
Project period: may 2014 - july 2016 Funding (kSEK) 2014 2015 2016 Total STERF 0 0 0 0 Other sources 1) 240 0 0 240 TOTAL 240 0 0 240 1) The project is funded by Syngenta and carried out according to the Contract Service Evaluation Agreement between STERF and Syngenta.
Principal investigator / contact person Trygve S. Aamlid, The Norwegian Institute for Agricultural and Environmental Research,
Bioforsk Turfgrass Research Group, Landvik, N-4886 Grimstad, Norway. Phone + 47 90 52 83 78. E-mail: trygve.aamlid@bioforsk.no Co-applicants Tatsiana Espevig, Bioforsk Landvik, Norway Trond Pettersen, Bioforsk Landvik, Norway Project objectives
To determine the effect of the soil surfactant Qualibra vs. Revolution on soil water content, hydrophobicity and turf quality of creeping bentgrass greens under a deep and infrequent and redundant irrigation regimes
Project summary and status as of 1 January 2015
This project was started in May 2014 on a USGA-spec. green with a one year old cover of creeping bentgrass Bioforsk Landvik, Norway. The trial followed a split plot design with four replicates; two irrigation regimes on main plots and surfactants (No surfactant control, Qualibra and Revolution) on subplots. The irrigation regimes were ‘FC x 1’ (=irrigation to field capacity once a week) , and ‘Excess x 2’ (=irrigation twice per week with 50% more water than needed to replenish FC). The plots were irrigated using a manually operated irrigation boom, the amount of water to being calcaluated from TDR measurements (20 cm depth) and an anticpated soil water content at FC of 20 %. Both surfactants were applied at a rate 20 L in 800 L water ha-1 at monthly intervals from 1 May to 1 September. The first part of the growing season 2014 was dry with only 84 mm natural rainfall from 15 May to 31 July. The dry period perod culminated with a very warm week with daily maximums close to 30 °C in late July. In contrast, August and September had more than 300 mm rainfall. For this reason, the experimental data were analysed seperately for the two periods. The irrigation treatment ‘Excess x 2’ improved visual turf quality significantly over ‘FC x 1’ during the first ‘dry’ period, but this tended to be reversed during the latter ‘wet’ period. Both surfactants acted as penetrants and reduced the soil water content by 10-20 % during the ‘dry’ as well as during the ‘wet’ period. The reduction occurred regardless of irrigation regime and was stronger in the top 5 cm (5 cm TDR probes) than on average for the top 20 cm rootzone. The reduction was slightly, but not significantly, stronger with Revolution