S13 - Session O3 - Groundcover management strategies for improving fruit set by alleviating abiotic stresses and enhance soil organic carbon and nitrogen contents in a sweet cherry orchard in Okanagan Valley, Canada

Authors: Mehdi Sharifi *, Hao Xu, Daniell Ediger, Bill Rabie, Sarah Gafner-Bergeron, Sebastian Damin

Sweet cherry ( Prunus avium ) is a high-value fruit product in Canadian domestic and international markets, and the importance of its sustainable production is significant to the horticultural industry. A three-year study aimed to explore the effect of three groundcover treatments including control (CON), bark and wood chips mulch (BWM) and woven black geotextile (WBG) on improving sweet cherry fruit set through alleviating abiotic stresses in Summerland, British Columbia, Canada. Treatments are arranged in Randomized Complete Block Design with 6 replications. The research initiated in 2019 in a 4-year old Lapins on Krymsk 5 rootstock block. BWM treatment applied in-row at a rate of 250 m 3 ha -1 in the first year and topped up of 167 m 3 ha -1 every other year. Soil moisture and temperature were continuously monitored during the growing season. Soil volumetric moisture ranged from 0.15 to 0.28% and soil temperature ranged from 11 to 24 o C. Yield did not affect by treatments except for 2020 which CON produced more yield than WBG and BWM. The only fruit quality parameters that affect by treatments were soluble solids, TA, size and firmness. CON resulted in the lowest soluble solids values followed by WBG only in 2020 with similar trend in 2021. Larger fruit were measured in CON than BWM but not different than WBG in 2020 and 2021. Fruits in CON showed greater firmness values relative to WBG and BWM only in 2021. Treatments did not affect Leaf N or tree cross sectional area. Mulch and geotextile reduced the mid and late season leaf water potential compared with CON in 2020. BWM reduced the photosynthetic rates in July 2020 compared with CON and WBG. In 2021, only August photosynthetic rates were greater in BMW and WBG compared with CON. Leaf water potential was greater in CON than BMW and WBG at the end of July 2021. Overall, groundcover treatments did not have a profound and consistent effect on fruit set, yield and fruit quality of sweet cherries.