Aquaculture America 2020

February 9 - 12, 2020

Honolulu, Hawaii

OPTIMIZING AQUAPONIC STRAWBERRY PRODUCTION IN THE NORTHEAST FOR YEAR-ROUND PRODUCTION

 
Anna DeVitto, Anissa Poleatewich, Peter Konjoian, Neil Mattson, Todd Guerdat*
University of New Hampshire
Department of Agriculture, Nutrition, and Food Systems
38 Academic Way
Durham, NH 03824
todd.guerdat@unh.edu

In the Northeastern US, locally produced strawberries are only available during the summer months. The majority of fresh market strawberries come from field-production in California, Florida, and Mexico. To meet consumer demand for locally produced food, controlled environment agricultural (CEA) systems can enable year-round strawberry production. The use of CEA systems can reduce the impact of extreme weather on crops, reduce pest and disease pressures, and automate environmental parameters to target specific crop needs. There is a need to identify optimal cultivation techniques specific to day-neutral cultivars to justify economic viability of CEA strawberries in the U.S.  To do so, we first (1) evaluated cultivars and substrates best suited for greenhouse production as preliminary research for the following two experiments. The three cultivars Albion, San Andreas, and Seascape were grown in a peat-based and peat-coconut coir blend, and yields were collected over 8 weeks. Results showed that there was no significant effect of the interaction between cultivar and substrate on yield, however there was a trend in the data revealing Seascape producing the highest yields regardless of substrate. Furthermore, Seascape produced significantly greater yields than Albion and San Andreas at week 3 of production. Secondly (2), we compared yields and overall quality of strawberries grown using a synthetic nutrient solution, a naturally-derived solution, and a naturally-derived solution supplemented with phosphoric acid. The naturally-derived solutions were sourced from a recirculating aquaponics system. Using aquaculture effluent as a fertilizer for plants has shown to be extremely successful for leafy greens, but more research is needed to evaluate the feasibility of using aquaculture effluent for strawberry production. Results from this experiment revealed a trend where both aquaponic treatments had higher total yields and greater number of fruit than the hydroponic treatment. Non-augmented aquaponic plants irrigated with low levels of phosphorous produced higher yields than hydroponic plants irrigated with higher levels of phosphorous, however plant biomass was significantly reduced. Thirdly (3), we quantified the supplemental lighting needs, based on daily light integral (DLI), to optimize production during the 'off seasons' when rates of photosynthesis are greatly reduced. Plants were grown under 14, 20, and 26 mol photons-1 m-2 day-1 of light with an 18 hour photoperiod to determine the effect of DLI on plant performance of day-neutral strawberries. Results from this study revealed that plants grown under a DLI of 26 produced significantly higher yields, a greater number of fruit, and higher sugar content than when grown under a DLI of 14. These results illuminate certain growing techniques that should be implemented in large scale greenhouse operations to optimize production of day-neutral strawberries grown in greenhouses.