Source: UNIV OF THE VIRGIN ISLANDS submitted to
DEVELOPMENT OF AQUAPONIC TECHNOLOGY FOR THE PRODUCTION OF TILAPIA AND HYDROPONIC CROPS.
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0226104
Grant No.
(N/A)
Project No.
VI-201012
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Oct 1, 2011
Project End Date
Sep 30, 2016
Grant Year
(N/A)
Project Director
Ferrarezi, RH, .
Recipient Organization
UNIV OF THE VIRGIN ISLANDS
(N/A)
ST. CROIX,VI 00850
Performing Department
Research & Land Grant Affairs
Non Technical Summary
The expanding aquaponic producer community needs to know which alternatives to existing designs add value to their business. Differences in available resources drive them to seek alternative management strategies which will be addressed by this project.
Animal Health Component
0%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
3073714106050%
2051499106050%
Goals / Objectives
The objectives of this project are to 1) optimize tilapia production, 2)evaluate new aquaponic system components and develop a system for hobby-scale, 3) evaluate vegetable varieties, and 4) conduct an economic analysis.
Project Methods
Six replicated research-scale systems and one commercial-scale system will be used in studies with application of acquired knowledge to the subsequent objective. Research-scale systems will evaluate components and tilapia production strategies. The commercial-scale system will evaluate vegetable varieties.

Progress 10/01/11 to 09/30/16

Outputs
Target Audience:The target audience is US Virgin Island farmers who are seeking aquaculture production technologies that conserve land and water and reduce pollution discharge by vegetable crop production that recovers nutrients from fish waste. The secondary audience is international entrepreneurs, farmers, teachers and students looking to apply the most recent research to their aquaponic systems. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Three hundred and thirteen (313) individuals were trained from 2011 to 2016 at the UVI Aquaponics Workshop. The 3-day workshop presents the principles of design and operation of the UVI Aquaponic System. The workshop consists of 9 hours of classroom lectures and 7.5 hours of field experience. The project also allowed students, faculty and professional staff to participate in several conferences such as the American Society of Horticultural Sciences, UVI Research Day, Caribbean Food Crops Society and Aquaculture America. How have the results been disseminated to communities of interest?The results were shared to local farmers, agricultural agents, the U.S. Virgin Islands Department of Agriculture through personal communication, seminars, conference proceedings, and field days. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Goal #1 Mustafa, A., D.S. Bailey, and R.S. Ferrarezi. 2016. Aquaponic waste as nutrient source for duckweed production used for fish feed. UVI 2016 Research Day, April 15. Kingshill, U.S. Virgin Islands. Mustafa et al. (2016) determined the optimal sludge volumes for duckweed (Lemna minor) production. Our goal was to establish the guidelines for duckweed production in the U.S. Virgin Islands, providing basic information to increase the Aquaponics production in the territory and creating a possible source of incoming for local farmers interested in growing duckweed for Aquaponics growers. The solution nutrient content changed over 28 days indicating dramatic changes in NO3 content (from 0 to 17 mg/L). The yield more than double over 19 days (from 250 to 600 g). However, treatment with high sludge volumes showed the lowest yield, probably because the excessive algae growth and nutrient competition. Ferrarezi, R.S., D.S. Bailey, S. Balkaran, and J. Bernier. 2016. Partial root and canopy cutting to increase cantaloupe fruit sweetness in the UVI Commercial Aquaponic System. ASHS 2016 Annual Conference, August 8-11. Atlanta, Georgia. Ferrarezi et al. (2016) evaluated the effect of partial root and canopy cut (combination of partial cuts; 0%, 25%, 50% and 75%) performed before two different harvest schedules (10 days after cutting or at fruit maturation) on cantaloupe fruit sugar content. Even though the results indicated an increase in fruit sugar content, more research is necessary to develop an alternative cultural practice for increasing cantaloupe fruit sweetness in Aquaponics without compromising total yield. Cannella, L., A.R.A. Nassef, D. Bailey and R.S. Ferrarezi. 2016. Alternative sources of food for aquaponics in the U.S. Virgin Islands: A case of study with black soldier flies. UVI-AES 2016 Annual Report. In press. The Horticulture and Aquaculture program of University of the Virgin Islands (UVI) started growing black soldier flies (Hermetia illucens) (BSF) in order to evaluate the use of alternative sources of food to feed the tilapia (Oreochromis niloticus) in the UVI Commercial Aquaponics System (CAS). The project consists basically in the design, assembling, and operation of a unit to produce the BSF larvae. During 90 days we were able to produce 2,080 larvae, generating 318.5 g of BSF in 22.794 kg of compost and 4 m3 total available space. The production of the larvae is possible but the economy of scale to generate enough larvae to supplement the tilapia feed needs to be determined. Balkaran, S., D.S. Bailey, and D. Nandwani. 2014. Effect of foliar spray application of calcium and phosphorus on fruit production of zucchini (Cucurbita pepo). Proceedings of the Caribbean Food Crops Society. 50:186. The purpose of the study of Balkaran et al. (2014) was to quantify zucchini (Cucurbita pepo var. cylindrica) production when foliar sprayed with different levels of calcium and phosphorusFoliar application of both calcium and phosphorus was effective in elevation production number and mass for zucchini grown in an aquaponic system. Future research will evaluate combined nutrients to further enhance production. Goal #2 Bailey, D.S. and D. Nandwani. 2014a. Selection of an Aquaculture Production System for Farmers in the US Virgin Islands. Book of Abstracts, p 24, Aquaculture America 2014. February 9-12, 2014. Seattle WA. An aquaponic system combines the production of fish and vegetables in an integrated system that combines water and pumping resources while reclaiming fish waste as nutrients for plant growth. The system requires a high capital investment and ongoing operating costs, primarily feed and energy inputs. Fish and plants are grown at high densities to cover those costs and produce a regular income stream. The biofloc system is primarily a fish production system with the potential for agronomic production of vegetables. The system is moderately stocked with tilapia and relies on in situ use of fish waste by flocs of microscopic organisms: phototrophs, heterotrophs and autotrophs to maintain water quality. Initial capital investment is low and operating costs of feed and energy are moderate. Enterprise budgets, cash flow statements and balance sheet analysis are used by Bailey and Nandwani (2014a) to evaluate the investment and choose the appropriate production system that meets the farmer's goals. Bailey, D.S. and D. Nandwani. 2014b. Selection of an aquaculture production system for farmers in the US Virgin Islands. Proceedings of the Caribbean Food Crops Society. 50:185. The UVI Aquaponic System in particular has been adopted by many entrepreneurs in temperate zones facing the same limitations of available land and water and the desire to reclaim nutrients instead of discharging them into the environment. Adoption of these aquaculture systems by U.S. Virgin Islands farmers has been limited. Most attempts to implement the technology have been on the home/hobby scale. Only one investor developed a commercial-scale farm which ceased operation after a hurricane in 1995. To better inform local farmers about the production and costs of the UVI designed systems a decision tree was developed by Bailey and Nandwani (2014b). A decision tree helps farmers select a production system given their individual constraints: access to capital and availability of land and water. An assumption is made for equal production of tilapia and the costs associated with that production is evaluated for each system. Evaluation of FCR, survival, production (kg/m3 and kg/ha), energy inputs (kg/kWh) and labor guide the decision process. The addition of vegetable crops in hydroponic beds or adjacent fields adds additional costs and revenues to both systems. Given this decision making process, a farmer can make an informed decision and select the best production system for his enterprise. Goal #3 Bailey, D.S., S. Balkaran, J. Bernier, and R.S. Ferrarezi. 2016. Assessment of basil varieties for production in the UVI Commercial Aquaponic System. ASHS 2016 Annual Conference, August 8-11. Atlanta, Georgia. Bailey et al. (2016) conducted two trials to assess different basil varieties for production in Aquaponics. In the first trial (Summer 2015), they evaluated five basil varieties ('Genovese', 'Spicy Globe', 'Lemon', 'Purple Ruffles' and 'Red Rubin'). Based on our results, we recommend 'Spicy Globe' and 'Genovese' during Summer and Fall, were Cinnamon' is also an alternative. The total yield reflected the measured plant morphology. Varieties with smaller plant size can be spaced closely to increase total yields. Goal #4 Bailey D.S. and R.S. Ferrarezi. 2016. Valuation of vegetable crops produced in the UVI commercial aquaponic system. UVI-AES 2016 Annual Report. In press. The crops studied by Bailey and Ferrarezi (2016) were spaced at a density of 30 plants per meter square and harvested after a production period of 3 weeks. By harvesting mature leaves at 3 week intervals pest populations were kept in check. Data on yield was collected at each harvest. Value of each crop per kilogram was obtained from a USDA ERS for the Miami terminal over the year May 2015 - April 2016. These values were then converted into value per week which allows comparison to crops with different production periods. Roselle had the highest expected value of $1.89/m2/week. Cucumber had the next highest range of expected value, $1.24-1.32/m2/week followed by zucchini ($0.62-0.89), okra ($0.53-0.62) and cantaloupe ($0.14-0.16). Cantaloupe is planted at the lowest density, 0.67/m2 and has a long production period of 13 weeks.

Publications

  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Ferrarezi, R.S., G.M. Weaver, M.W. van Iersel, and R. Testezlaf. 2015. Subirrigation: Historical overview, challenges, and future prospects. HortTechnology 25(3): 262-276. URL: http://horttech.ashspublications.org/content/25/3/262.full.pdf?ijkey=owapM8C96s2GCqe&keytype=ref (cover article)
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Ferrarezi, R.S., M.W. van Iersel, and R. Testezlaf. 2015. Monitoring and controlling ebb-and-flow subirrigation with soil moisture sensors. HortScience 50(3): 447-453. URL: http://hortsci.ashspublications.org/content/50/3/447.full.pdf?ijkey=i19jYAJh0pzNz3p&keytype=ref
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Ferrarezi, R.S., S.K. Dove, and M.W. van Iersel. 2015. An automated system for monitoring soil moisture and controlling irrigation using low-cost open-source microcontrollers. HortTechnology 25(1): 110-118. URL: http://horttech.ashspublications.org/content/25/1/110.full.pdf?ijkey=SLdVepEJOcRwcp9&keytype=ref
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Geiger, T.C., K. Cuffy, and R.S. Ferrarezi. 2016. Greenhouse production of slicing cucumbers in the U.S. Virgin Islands. UVI 2016 Research Day, April 15. Kingshill, U.S. Virgin Islands.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Greenidge, J., J. Atemazem, T.C. Geiger, and R.S. Ferrarezi. 2016. Evaluating microirrigation performance on okra cultivation in the U.S. Virgin Islands. UVI 2016 Research Day, April 15. Kingshill, U.S. Virgin Islands.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Mustafa, A., D. Bailey, and R.S. Ferrarezi. 2016. Aquaponic waste as nutrient source for duckweed production used for fish feed. UVI 2016 Research Day, April 15. Kingshill, U.S. Virgin Islands.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Weiss, S., R.S. Ferrarezi, D.D. Treadwell, K.P. Beamer, and T.C. Geiger. 2016. Mulching strategies using conservation tillage for weed management in tropical organic hot pepper cropping systems. ASHS 2016 Annual Conference, August 8-11. Atlanta, Georgia.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Ferrarezi, R.S., S.K. Dove, M.W. van Iersel, and R.M.L. Silva. 2015. Low-cost open-source microcontrollers to build automated irrigation and fertigation systems using soil moisture and electrical conductivity sensors. HortScience 50(9): S384 (Abstr.). New Orleans/LA, United States.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Geiger, T.C., K.P. Beamer, S.A. Weiss, and R.S. Ferrarezi. 2015. Performance of nine butternut squash varieties in summer in the U.S. Virgin Islands. HortScience 50(9): S336 (Abstr.).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: van Iersel, M.W., R.S. Ferrarezi, G.M. Weaver, and E. Mattos. 2015. A biofeedback system for plant-driven photosynthetic lighting. HortScience 50(9): S219-S220 (Abstr.). New Orleans/LA, United States.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Weaver, G., M.W. van Iersel, E. Mattos, and R.S. Ferrarezi. 2015. Chlorophyll fluorescence measurements can indicate carbon fixation rates of lettuce. HortScience, v.50, n.9, S159-S160 (Abstr.). New Orleans/LA, United States.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Weiss, S., R.S. Ferrarezi, K.P. Beamer, and D.D. Treadwell. 2015. Tropical cover crop mulch systems for low-external-input reduced-tillage vegetable production. HortScience 50(9): S169-S170 (Abstr.). New Orleans/LA, United States.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Weiss, S., R.S. Ferrarezi, T.C. Geiger, K.P. Beamer, and D.D. Treadwell. Utilizing the cover crop sunn hemp (Crotalaria juncea) to improve tropical organic vegetable cropping systems. American Society of Agronomy (ASA), Crop Soil Society of America (CSSA), and Soil Science Society of America (SSSA) 2015 Conference (Abstr.), Nov 15-18, 2015. Minneapolis/MN, United States.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Bailey, D.S. and D. Nandwani. 2014a. Selection of an aquaculture production system for farmers in the US Virgin Islands. Book of Abstracts, p 24, Aquaculture America 2014. February 9-12, 2014. Seattle WA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Bailey, D.S. and D. Nandwani. 2014b. Selection of an aquaculture production system for farmers in the US Virgin Islands. Proceedings of the Caribbean Food Crops Society. 50:185.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Napoleon-Fanis, V. and D. Nandwani. 2013. The effects of preemeergence herbicides on the growth, yield and quality of transplanted watermelon. Proceedings of the Caribbean Food Crops Society 49:467-475. (Abstr.).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Balkaran, S., D.S. Bailey, and D. Nandwani. 2014. Effect of foliar spray application of calcium and phosphorus on fruit production of zucchini (Cucurbita pepo). Proceedings of the Caribbean Food Crops Society. 50:186.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Nandwani, D., J.R. Williamson, S. Crossman, and V. Forbes. 2014. Cucumber cultivar study in the U.S. Virgin Islands. Proceedings of the Caribbean Food Crops Society 50:157-161 (Abstr.).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Nandwani, D., S. Dennery, V. Forbes, and T. Geiger. 2014. Yield of tomato cultivars grown in the organic management in the U.S. Virgin Islands. HortScience 49(9): S279 (Abstr.).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2012 Citation: Nandwani, D. 2012a. Growth and yield response of sweet pepper cultivars in the U.S. Virgin Islands. Proceedings of the Caribbean Food Crops Society 48:231-237. (Abstr.).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2012 Citation: Nandwani, D. 2012b. Weed control in okra [Abelmoschus esculentus (L). Moench] in the U.S. Virgin Islands. Hortscience 48(9): S272-273 (Abstr.).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2012 Citation: Nandwani, D. and V. Forbes. 2012. Growth and yield response of eight hot pepper varieties in the U.S. Virgin Islands. Hortscience 47(9): S303 (Abstr.).
  • Type: Other Status: Published Year Published: 2016 Citation: Cannella, L., A.R.A. Nassef, D. Bailey, and R.S. Ferrarezi. 2016. Alternative sources of food for aquaponics in the U.S. Virgin Islands: A case of study with black soldier flies. University of the Virgin Islands Agricultural Experiment Station 2016 Annual Report.
  • Type: Other Status: Accepted Year Published: 2016 Citation: Bailey D. and R.S. Ferrarezi. 2016. Valuation of vegetable crops produced in the UVI Commercial Aquaponic System. University of the Virgin Islands Agricultural Experiment Station 2016 Annual Report.
  • Type: Other Status: Published Year Published: 2015 Citation: Geiger, T.C., K.P. Beamer, S.A. Weiss, and R.S. Ferrarezi. 2015. Preliminary evaluation of sugar snap and snow pea varieties for production in the U.S. Virgin Islands. University of the Virgin Islands Agricultural Experiment Station 2015 Annual Report. URL: http://www.uvi.edu/files/documents/Research_and_Public_Service/AES/AES%202015%20Annual%20Report.pdf.
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2016 Citation: Ferrarezi, R.S., A.C. Ferreira Filho, and R. Testezlaf. 2016. The substrate moisture retention in subirrigation is influenced by the water height and irrigation time. Horticultura Brasileira 34(4). In press. (in Portuguese)
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2016 Citation: Ferrarezi, R.S., S.A. Weiss, T.C. Geiger, and K.P. Beamer. 2016. Edible-pod peas as high-value crops in the U.S. Virgin Islands. HortTechnology 26(4). In press.
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2016 Citation: Kang, J.-G., R.S. Ferrarezi, S.K. Dove, G.M. Weaver, and van Iersel, M.W. 2016. Increased fertilizer levels do not prevent ABA-induced chlorosis in pansy. HortTechnology 26(5). In press.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Salvador, C.A., R.S. Ferrarezi, C.V.G. Barreto, and R. Testezlaf. 2016. Method to evaluate the efficiency of manual overhead irrigation in citrus rootstock liner production. Engenharia Agr�cola 36(4). In press.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: van Iersel, M.W., G.M. Weaver, M.T. Martin, R.S. Ferrarezi, E. Mattos, and M. Haidekker. 2016. A chlorophyll fluorescence-based biofeedback system to control photosynthetic lighting in controlled environment agriculture. Journal of the American Society for Horticultural Science 141(2): 169-176. URL: http://journal.ashspublications.org/content/141/2/169.full.pdf+html.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Barreto, C.V.G., R.S. Ferrarezi, R. Testezlaf, and F.B. Arruda. 2015. Growth and physiological responses of Rangpur lime seedlings irrigated by a prototype subirrigation tray. HortScience 50(1): 123-129. URL: http://hortsci.ashspublications.org/content/50/1/123.full.pdf?ijkey=ZnULoBkjwO7pEz6&keytype=ref
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Bailey, D., S. Balkaran, J. Bernier, and R.S. Ferrarezi. 2016. Assessment of basil varieties for production in the UVI Commercial Aquaponic System. ASHS 2016 Annual Conference, August 8-11. Atlanta, Georgia.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Bailey, D., S. Balkaran, J. Bernier, and R.S. Ferrarezi. 2016. Assessment of basil varieties for production in the UVI Commercial Aquaponic System. UVI 2016 Research Day, April 15. Kingshill, U.S. Virgin Islands.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Ferrarezi, R.S., D. Bailey, S. Balkaran, and J. Bernier. 2016. Partial root and canopy cutting to increase cantaloupe fruit sweetness in the UVI Commercial Aquaponic System. ASHS 2016 Annual Conference, August 8-11. Atlanta, Georgia.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Ferrarezi, R.S., D. Bailey, S. Balkaran, and J. Bernier. 2016. Partial root and canopy cutting to increase cantaloupe fruit sweetness in the UVI Commercial Aquaponic System. UVI 2016 Research Day, April 15. Kingshill, U.S. Virgin Islands.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Ferrarezi, R.S., T.C. Geiger, and K. Cuffy. 2016. Sensor-based irrigation in different sweet pepper varieties in the U.S. Virgin Islands. ASHS 2016 Annual Conference, August 8-11. Atlanta, Georgia.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Ferrarezi, R.S., T.C. Geiger, and K. Cuffy. 2016. Sensor-based irrigation in different sweet pepper varieties in the U.S. Virgin Islands. UVI 2016 Research Day, April 15. Kingshill, U.S. Virgin Islands.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Geiger, T.C., K. Cuffy, and R.S. Ferrarezi. 2016. Greenhouse production of slicing cucumbers in the U.S. Virgin Islands. ASHS 2016 Annual Conference, August 8-11. Atlanta, Georgia.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Ferrarezi, R.S., M.W. van Iersel, and R. Testezlaf. 2016. Plant growth response of subirrigated salvia Vista Red to increasing water levels at two substrates. Horticultura Brasileira 34(2): 202-209. DOI: http://dx.doi.org/10.1590/S0102-053620160000200009.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Ferrarezi, R.S. and R. Testezlaf. 2016. Performance of wick irrigation system using self-compensating benches with substrates for lettuce production. Journal of Plant Nutrition 39(1): 150-164. DOI: http://dx.doi.org/10.1080/01904167.2014.983127.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Ferrarezi, R.S., M.W. van Iersel, and R. Testezlaf. 2015. Use of subirrigation for water stress imposition in a semi-continuous CO2-exchange system. Ornamental Horticulture 21(2): 235-242. DOI: http://dx.doi.org/10.14295/aohl.v21i2.699 (in Portuguese).


Progress 10/01/15 to 09/30/16

Outputs
Target Audience:The target audience is US Virgin Island farmers who are seeking aquaculture production technologies that conserve land and water and reduce pollution discharge by vegetable crop production that recovers nutrients from fish waste. The secondary audience is international entrepreneurs, farmers, teachers and students looking to apply the most recent research to their aquaponic systems. Changes/Problems:In the project Evaluation of Pacu (Colossoma macropomum) in a biofloc tank culture system planned for this period, the import permit was obtained (attached), fish was ordered from the Dominican Republic but never delivered to UVI due to logistical problems from the supplier. What opportunities for training and professional development has the project provided?Thirty-one individuals were trained in 3 sessions of the UVI Aquaponics Workshop. The 3-day workshop presents the principles of design and operation of the UVI Aquaponic System. The workshop consists of 9 hours of classroom lectures and 7.5 hours of field experience. Three participants came from the USVI and 13 from the USA. Fifteen other participants came from neighboring North and Central America, Asia and Europe (Austria, Bahamas, Bahrain, Bonaire, BVI, Canada, Egypt, Indonesia, Italy, Jamaica and Trinidad & Tobago), reflecting the global impact of this UVI developed aquaculture technology. Through the participation at the American Society of Horticultural Sciences 2016 Conference (Atlanta, GA), and at the UVI Research Day 2016 (St. Croix, VI). How have the results been disseminated to communities of interest?These results will be shared to local farmers, agricultural agents, the USVI Department of Agriculture through seminars, factsheets, and field days What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Goal #1 ALTERNATIVE SOURCES OF FOOD FOR AQUAPONICS IN THE U.S. VIRGIN ISLANDS: A CASE OF STUDY WITH BLACK SOLDIER FLIES The Horticulture and Aquaculture program of University of the Virgin Islands (UVI) started growing black soldier flies (Hermetia illucens) (BSF) in order to evaluate the use of alternative sources of food to feed the tilapia (Oreochromis niloticus) in the UVI Commercial Aquaponics System (CAS). The project consists basically in the design, assembling, and operation of a unit to produce the BSF larvae. The growing unit was designed from different sources available online, focusing primarily on having all the growing stages being performed at the same structure. We started with an initial population of 5,000 larvae. In the beginning the BSF production presented several issues related to the identification of the proper food source and the amount of food that should be provided. The system was improved to increase the number of larvae been produced. During 90 days we were able to produce 2,080 larvae, generating 318.5 g of BSF in 22.794 kg of compost and 4 m3 total available space. The production of the larvae is possible but the economy of scale to generate enough larvae to supplement the tilapia feed needs to be determined. Goal #2 Strict NFT hydroponics vs Aquaponics comparison Objectives: Compare plant growth on Aquaponics systems with different feed inputs (60 and 100 g/m2) vs strict NFT hydroponics. Hypothesis: Hydroponics will provide higher plant yield, but the Aquaponics will have higher final profitability when taking the fish production in consideration. Treatments. Three systems (Aquaponics with low fish stock, Aquaponics with high fish stock and strict NFT hydroponics) and four crops with different nutrient requirements in each system. Experimental design: Complete randomized design arranged in split-plot, and three replications. The systems will be randomly assigned to whole plots (main plots), and the crops randomly assigned to split plots (subplots) within each whole plot. Aquaponic waste as nutrient source for duckweed production used for fish feed Our objective is to determine the optimal nitrate concentration for duckweed production. We tested four nitrate concentrations (0, 27, 54 and 80 mg/L) on twelve 3.6-m diameter × 1.22-m deep round culture tanks, with three replications. Initial sludge nutrient content and proximate analysis, and weekly water quality analysis, duckweed harvest and yield determination will be performed during 12 weeks. Our goal is to establish the guidelines for duckweed production at the U.S. Virgin Islands, providing basic information to increase the aquaponics production in the territory and creating a possible source of incoming for local farmers interested in growing duckweed for aquaponics growers. Data is under analysis. Goal #3 Improving cantaloupe fruit sugar content in the UVI Commercial Aquaponic System Our study evaluated the effect of partial root and canopy cut performed before two different harvest schedules on cantaloupe fruit sugar content. The UVI Commercial Aquaponic System used consisted of three main components: fish rearing, solids removal and hydroponic vegetable production troughs. The hydroponic troughs were 30×1.2×0.3 m with a volume of 11.3 m3 and a surface area of 214 m2. The water flow rate on the troughs was 125 L/min for a retention time of 3 h. Fish waste products were the source of nutrients for plant growth. Three-week old cantaloupe 'Goddess' seedlings grown on peat-based substrate were transplanted into 1.2×2.4-m (2.97 m2) styrofoam rafts on the aquaponics system on Oct 2, 2015 (day after transplanting, DAT 1). We planted 2 plants/raft spaced every 1.2×1.2 m in a density of 1.485 plants/m2 and used 12 rafts/trough. Our treatments were the combination of partial root and canopy cuts (0%, 25%, 50% and 75%) in two harvest schedules (10 days after cutting or at fruit maturation), resulting in 20 treatments, in a CRD with two replications. The root and canopy cutting was performed on DAT 37. The first and last harvest were performed on DATs 47 and 64. Sugar content increased only on the treatments with no root cut, 75% and 25% of canopy cut and fruits harvested at the maturation (9.1 and 8.4°Brix), with a negative effect on the treatment with 75% of root cut, no canopy cut and fruits harvested at the maturation (3.7°Brix) (p=0.0060). The treatment with no root or canopy cut and fruits harvested at the maturation promoted the highest yield (30,227 kg/ha), indicating a negative effect of the partial cutting on fruit total yield (p=0.0072). No treatment response was found on fruit length and width, fruit hardness, fruit pulp thickness, leaf chlorophyll and anthocyanin content, root and shoot dry weight and shoot fresh weight (p>0.05). Even though our results indicated an increase in fruit sugar content, more research is necessary to develop an alternative cultural practice for increasing cantaloupe fruit sweetness in aquaponics without compromising total yield. Goal #4 VALUATION OF VEGETABLE CROPS PRODUCED IN THE UVI COMMERCIAL AQUAPONIC SYSTEM Each crop yields different value per unit area and this must be considered when selecting varieties to produce to provide the highest returns to the farmer. Taking the factors of density, growth period, yield and value into account gives a value per area per time ($/m2/week) which can be used to compare economic returns and make informed management choices. The crops studied by Bailey and Ferrarezi (2016) were spaced at a density of 30 plants per meter square and harvested after a production period of 3 weeks. One main consideration for the short production period was the establishment of pests, aphids and/or white fly, on crops grown longer than 3 weeks. By harvesting mature leaves at 3 week intervals pest populations were kept in check. Data on yield was collected at each harvest. Full heads were harvested for pah choi, leaves were harvested from kale, collards and Swill chard. Basil was planted at 16 plants per meter square and grown for 4 weeks. They were harvested by a "cut and come again" technique which trims upper leaves and stems leaving 15 cm of plant to regrow. Value of each crop per kilogram was obtained from a USDA ERS for the Miami terminal over the year May 2015 - April 2016. These values were then converted into value per week which allows comparison to crops with different production periods. Basil has the highest expected value of $3.96-4.96/m2/week followed by Pak choi with $3.92-4.32/m2/week. These crops had the highest biomass yield and that factor impacted the end value. Swiss Chard had low value with a range of value of $1.02-1.19/m2/week. Kale and collards yielded even less with $0.34-0.37 and 0.21-0.23/m2/week respectively. A similar economic analysis was made for fruiting crops roselle, cantaloupe, cucumber, okra and zucchini. Planting density and growth period were different for each crop. Yield data was recorded for each harvest over the production period and calculated on an area basis. Crop market value was determined from USDA Miami Terminal over the year May 2015 - April 2016. Roselle is a specialty crop whose price is not available from the USDA report. The local roadside market price of $8.82/kg was used. Roselle had the highest expected value of $1.89/m2/week. Cucumber had the next highest range of expected value, $1.24-1.32/m2/week followed by zucchini ($0.62-0.89), okra ($0.53-0.62) and cantaloupe ($0.14-0.16). Cantaloupe is planted at the lowest density, 0.67/m2 and has a long production period of 13 weeks.

Publications

  • Type: Other Status: Published Year Published: 2016 Citation: Cannella, L., A.R.A. Nassef, D. Bailey and R.S. Ferrarezi. Alternative sources of food for aquaponics in the U.S. Virgin Islands: A case of study with black soldier flies. University of the Virgin Islands Agricultural Experiment Station 2016 Annual Report.
  • Type: Other Status: Published Year Published: 2016 Citation: Bailey D. and R.S. Ferrarezi. Valuation of vegetable crops produced in the UVI Commercial Aquaponic System. University of the Virgin Islands Agricultural Experiment Station 2016 Annual Report.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: FERRAREZI, R.S.; BAILEY, D.; BALKARAN, S.; BERNIER, J. 2016. Partial root and canopy cutting to increase cantaloupe fruit sweetness in the UVI Commercial Aquaponic System. ASHS 2016 Annual Conference, August 8-11. Atlanta, Georgia.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: BAILEY, D.; BALKARAN, S.; BERNIER, J.; FERRAREZI, R.S. Assessment of basil varieties for production in the UVI Commercial Aquaponic System. ASHS 2016 Annual Conference, August 8-11. Atlanta, Georgia.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: MUSTAFA, A.; BAILEY, D.; FERRAREZI, R.S. 2016. Aquaponic waste as nutrient source for duckweed production used for fish feed. UVI 2016 Research Day, April 15. Kingshill, U.S. Virgin Islands.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: FERRAREZI, R.S.; BAILEY, D.; BALKARAN, S.; BERNIER, J. 2016. Partial root and canopy cutting to increase cantaloupe fruit sweetness in the UVI Commercial Aquaponic System. UVI 2016 Research Day, April 15. Kingshill, U.S. Virgin Islands.


Progress 10/01/14 to 09/30/15

Outputs
Target Audience:The target audience is US Virgin Island farmers who are seeking aquaculture production technologies that conserve land and water and reduce pollution discharge by vegetable crop production that recovers nutrients from fish waste. The secondary audience is international entrepreneurs, farmers, teachers and students looking to apply the most recent research to their aquaponic systems. Changes/Problems:No significant changes to the project occurred during this reporting period. What opportunities for training and professional development has the project provided?Sixty-seven individuals were trained in 4 sessions of the UVI Aquaponics Workshop. The 3-day workshop presents the principles of design and operation of the UVI Aquaponic System. The workshop consists of 9 hours of classroom lectures and 7.5 hours of field experience. Eight participants came from the USVI, 16 from Puerto Rico and 25 from the USA. Eighteen other participants came from neighboring Caribbean islands, North Central and South America, Africa and Europe, reflecting the global impact of this UVI developed aquaculture technology. How have the results been disseminated to communities of interest?Through the participation at the Aquaculture America 2015 (New Orleans, LA) and at the UVI Research Day 2015 (St. Croix, VI). What do you plan to do during the next reporting period to accomplish the goals?Goal #1 Aquaponic waste as nutrient source for duckweed production used for fish feed The University of the Virgin Islands (UVI), Agriculture Experiment Station (AES) has developed an aquaponic system which produces tilapia and vegetable/ornamental crops in an integrated recirculating system. Waste products from fish metabolism are dissolved in the water and treated by nitrifying bacteria before the water is recycled back to the fish tanks. The fecal waste is removed from the system as a slurry mix of solids and water. The mineralized sludge waste water can be used to grow crops that can fed the fish instead of being discharged into the environment. Tilapia produced in the commercial aquaponic system are raised in tanks and have no access to naturally produced food sources. Producing plant-based feed using waste water to supplement the diet and substitute for purchased feed will reduce environmental impact and have economic advantages decreasing aquaponic production costs. Our objectives are 1) determine the needed facilities and water requirements to produce duckweed as a supplemental source of food and 2) determine fish growth rates when pelletized dried duckweed is provided as 10% of diet substitution. Two sequential studies will be performed at the UVI-AES Aquaponics facilities. On experiment 1, there will be four treatments (0, 25, 50 and 75 ppm of nitrate-nitrogen [NO3-N]) with three replications. Twelve 3.6 m diameter × 1.22 m deep round culture tanks will be used for the duckweed production. Initial sludge nutrient content, and weekly water quality analysis, duckweed harvest and yield determination, plant nutrient content and proximate analysis will be performed during 12 weeks. On experiment 2, we will test two treatments (100% commercial dry fish fed and 90% commercial dry fish fed + 10% pelletized dried duckweed) with three replications. Eight 2-m3 recirculating aquaculture rearing tanks will be used for the feed trial. The duckweed used will be grown using the best fertilization level obtained from experiment 1. A weekly sample will determine fish growth and increase in biomass. Monthly water quality analysis will be performed for the entire system to determine ammonia, nitrate, and dissolved oxygen. Final fish yield will be determined at the end of 24 weeks, and survival and feed conversion rate will be calculated. The study will determine the optimal nitrate concentration for duckweed production and if the cost of production of duckweed offsets the purchase price and shipping cost of feed at the U.S. Virgin Islands, increasing the aquaponics production in the territory and creating a possible source of incoming for local farmers interested in growing duckweed for aquaponics growers. Goal #2 Strict NFT hydroponics vs Aquaponics comparison Objectives Compare plant growth on Aquaponics systems with different feed inputs (60 and 100 g/m2) vs strict NFT hydroponics. Hypothesis Hydroponics will provide higher plant yield, but the Aquaponics will have higher final profitability when taking the fish production in consideration. Material and Methods Treatments. Three systems (Aquaponics with low fish stock, Aquaponics with high fish stock and strict NFT hydroponics) and four crops with different nutrient requirements in each system. Experimental design. Complete randomized design arranged in split-plot, and three replications. The systems will be randomly assigned to whole plots (main plots), and the crops randomly assigned to split plots (subplots) within each whole plot. Measurements. Environmental conditions Solution pH, EC, and Temperature DO and nutrients - NO3, Ca, K (daily) Plant growth height number of leaves yield (weekly and at end) Evaluation of Pacu (Colossoma macropomum) in a biofloc tank culture system Objectives Compare the new specie adaptation and fish growth in a biofloc tank at the U.S. Virgin Islands. Hypothesis Pacu (Colossoma macropomum) will adapt well to a tropical condition and grow faster than tilapia (Oreochromis niloticus) in a biofloc tank. Material and Methods Treatments. We are testing two fishes (pacus and tilapias) in round culture tanks, and three replications. The tanks are 3.6 m diameter × 1.22 m deep. These tanks are aerated with 0.5 cfm air diffuser (AS15L; Pentair, Apopka, FL) and a 1.5 hp regenerative blower (S45; Pentair; Apopka, FL). Experimental design. Complete randomized design. Measurements. Environmental conditions Solution pH, EC, and Temperature DO and nutrients - NO3, Ca, K (daily) Fish growth weight survival rate

Impacts
What was accomplished under these goals? We performed four variety trials during this reporting cycle: basil during Summer and Spring ('Genovese', 'Spicy Globe', 'Lemon', 'Purple Ruffles' and 'Red Rubin') and cantaloupes during Summer and Spring ('Gold Doubloon', 'Verona', and 'Goddess'). The data still being processed and analyzed. An abstract will be prepared for the 2016 ASHS conference in Atlanta and the 2016 UVI Research Day. Aquaponics is an integrated aquaculture and hydroponic production system. It is operated as a recirculating system with the hydroponic beds acting as a biofilter for nitrification of waste and the uptake of nitrate and other waste nutrients by vegetable crops. The intensive production of fish and vegetables in tanks requires energy inputs for water circulation and aeration to provide fish and nitrifying bacteria with oxygen for respiration and growth. The UVI Aquaponics System has continuous energy requirements of 3 hp; a 0.5 hp circulating water pump, and two regenerative blowers; 1.5 hp for fish production tank aeration and 1.0 hp for hydroponic bed aeration. The electrical power rate in the US Virgin Islands for Commercial Service is $0.50719 per kWh consisting of the Base Rate: $0.103832, Line Loss: $0.002196, Pilot Surcharge: $0.000686 and Fuel Charge: $0.400476 per kWh. This rate is three times the US national average and hinders the development of aquaponics in the territory. Alternative energy is often proposed as a solution to offset the high operational cost of electricity but an investment analysis is needed to determine if a capital investment with finance payments is a better option. Several alternative energy production scenarios exit, including solar, wind or mixed systems. Also, off-grid or grid-tied options exist and must be considered. An off-grid solar system requires extra power generation capacity during the day and storage batteries to operate the system through nighttime darkness as well as on overcast days, which adds to the capital investment required. Investment analysis will study annual cash flow for an aquaponic system powered conventionally from the public utility and compare with the alternative energy scenarios. Payback period, net present value and internal rate of return for each scenario will be used to evaluate the use of alternative energy from an investment perspective.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Donald S. Bailey. Can you use alternative energy to run this system? Investment analysis in aquaponic system design. UVI Research Day April 9, 2015 St. Croix USVI. p. 2.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Donald S. Bailey. Can you use alternative energy to run this system? investment analysis in aquaponic system design. Book of Abstracts p 42. Aquaculture America 2015, February 19-22, 2015. New Orleans, LA.


Progress 10/01/13 to 09/30/14

Outputs
Target Audience:The target audience is US Virgin Island farmers who are seeking aquaculture production technologies that conserve land and water and reduce pollution discharge by vegetable crop production that recovers nutrients from fish waste. The secondary audience is international entrepreneurs, farmers, teachers and students looking to apply the most recent research to their aquaponic systems Changes/Problems:No significant changes to the project occurred during this reporting period.There was no research faculty leading the program during the report period. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Throughthe participation at theAquaculture America 2014 in February 9-12 (Seattle WA) and at theCaribbean Food Crops Society 2014in July 6-11 (St. Thomas, VI). What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Donald S. Bailey and Dilip Nandwani. Selection of an Aquaculture Production System for Farmers in the US Virgin Islands. Book of Abstracts, p 24, Aquaculture America 2014 February 9-12, 2014. Seattle WA. Farmers in the Virgin Islands have several options to consider when choosing to add aquaculture production to their farm enterprise. Two tilapia production systems have been developed by the UVI-AES Aquaculture Program; they are aquaponics and biofloc production systems. Each of these systems has unique resource requirements, production inputs/outputs and potential to meet market requirements. A farmer must consider these opportunities and constraints in the selection of the system. An aquaponic system combines the production of fish and vegetables in an integrated system that combines water and pumping resources while reclaiming fish waste as nutrients for plant growth. The system requires a high capital investment and ongoing operating costs, primarily feed and energy inputs. Fish and plants are grown at high densities to cover those costs and produce a regular income stream. The biofloc system is primarily a fish production system with the potential for agronomic production of vegetables. The system is moderately stocked with tilapia and relies on in situ use of fish waste by flocs of microscopic organisms: phototrophs, heterotrophs and autotrophs to maintain water quality. Initial capital investment is low and operating costs of feed and energy are moderate. Enterprise budgets, cash flow statements and balance sheet analysis are used to evaluate the investment and choose the appropriate production system that meets the farmer's goals. Donald S. Bailey and Dilip Nandwani. Selection of an aquaculture production system for farmers in the US Virgin Islands. Proceedings of the Caribbean Food Crops Society. 50:185. 2014. Two aquaculture production systems have been developed by the University of the Virgin Islands Aquaculture Program - the UVI Aquaponic System and a biofloc system. The systems were designed to address the constraints and opportunities of local farmers and promote their integration with other traditional farming activities. The systems intensify production to minimize land requirements, conserve fresh water which is scarce and reclaim fish wastes as nutrients for either hydroponic or agronomic vegetable production. The program is well known for the development of design criteria and operation guidelines for these systems and has trained over 600 individuals from around the globe. The UVI Aquaponic System in particular has been adopted by many entrepreneurs in temperate zones facing the same limitations of available land and water and the desire to reclaim nutrients instead of discharging them into the environment. Adoption of these aquaculture systems by USVI farmers has been limited. Most attempts to implement the technology have been on the home/hobby scale. Only one investor developed a commercial-scale farm which ceased operation after a hurricane in 1995. To better inform local farmers about the production and costs of the UVI designed systems a decision tree was developed. A decision tree helps farmers select a production system given their individual constraints: access to capital and availability of land and water. An assumption is made for equal production of tilapia and the costs associated with that production is evaluated for each system. Evaluation of FCR, survival, production (kg/m3 and kg/ha), energy inputs (kg/kWh) and labor guide the decision process. The addition of vegetable crops in hydroponic beds or adjacent fields adds additional costs and revenues to both systems. Given this decision making process, a farmer can make an informed decision and select the best production system for his enterprise. Seti Balkaran, Donald S. Baileyand Dilip Nandwani. Effect of foliar spray application of calcium and phosphorus on fruit production of zucchini (Cucurbita pepo). Proceedings of the Caribbean Food Crops Society. 50:186. 2014. Abstract: The UVI Aquaponics System is a food production technology which integrates tank fish culture components with hydroponic vegetable cultivation. The integration conserves land and water and recovers waste nutrients from fish into a valuable vegetable crop. The primary waste from fish metabolism is ammonia-nitrogen which is converted by biological nitrification processes into nitrate-nitrogen which is used by plants to grow stems and leaves. Previous research at UVI-AES has focused on the production of lettuce and other leafy vegetables. Research has been limited on production of fruiting plants which need phosphorus and calcium to promote fruit set and produce quality fruit. The purpose of this study was to quantify zucchini production when foliar sprayed with different levels of calcium and phosphorus. To determine the effect of calcium on the zucchini production we look at both the marketable and nonmarketable production. In the calcium group, five set of plants were treated including a control group that was not treated. The application rates of 0.0 (control), 1.25, 2.50, 3.74 and 5.0 mg/l were applied weekly to the plant leaf surfaces. The plant that was sprayed with a 3.75 mg/l concentration of calcium was most effective and had a great production of zucchinis, 33.9/m2 for the production period. The control group however produced a high amount of unmarketable zucchinis (28.5/m2). The marketable yield mass of 7.5 kg/m2 with the 3.75 concentration was most effective. The same method was used to determine the effect of different levels of phosphorus on the zucchini plants. Five sets of plants were used for this experiment including a control group. The application rates of 0.0 (control), 0.5, 1.0, 1.5 and 2.0 mg/l were applied weekly. The plant that received the 1.00 mg/l concentration of phosphorus was most effective and had a great production of marketable zucchinis. It also yielded the highest mass (7.4 kg/m2). The plant that received 0.50 mg/l concentration of phosphorus was yielded the greatest number of unmarketable zucchinis. Foliar application of both calcium and phosphorus was effective in elevation production number and mass for zucchini grown in an aquaponic system. Future research will evaluate combined nutrients to further enhance production.

Publications

  • Type: Other Status: Published Year Published: 2014 Citation: Balkaran, S., D. Bailey, and D. Nandwani, EFFECT OF FOLIAR SPRAY APPLICATION OF CALCIUM AND PHOSPHORUS ON FRUIT PRODUCTION OF ZUCCHINI (Cucurbita pepo) Proceedings of the Caribbean Food Crops Society. 50:186. 2014
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Donald S. Bailey and Dilip Nandwani. SELECTION OF AN AQUACULTURE PRODUCTION SYSTEM FOR FARMERS IN THE US VIRGIN ISLANDS. Proceedings of the Caribbean Food Crops Society. 50:185. 2014 p. 185
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Donald S. Bailey and Dilip Nandwani. Selection of an Aquaculture Production System for Farmers in the US Virgin Islands. Book of Abstracts p 24 Aquaculture America 2014 February 9-12, 2014. Seattle WA


Progress 01/01/13 to 09/30/13

Outputs
Target Audience: Caribbean islands, North Central and South America, Africa and Europe, reflecting the global impact of this UVI developed aquaculture technology. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Sixty-seven individuals were trained in 4 sessions of the UVI Aquaponics Workshop. The 3-day workshop presents the principles of design and operation of the UVI Aquaponic System. The workshop consists of 9 hours of classroom lectures and 7.5 hours of field experience. Eight participants came from the USVI, 16 from Puerto Rico and 25 from the USA. Eighteen other participants came from neighboring Caribbean islands, North Central and South America, Africa and Europe, reflecting the global impact of this UVI developed aquaculture technology. How have the results been disseminated to communities of interest? A poster titled “Cucumber Production (Cucumis sativus) in the UVI Aquaponic System” was presented at the Caribbean Food Crops Society meeting presenting data and results from cucumber production research conducted in 2012. A paper to be published in the Proceedings of the Caribbean Food Crops Society was submitted. Wrote an abstract for Aquaculture America 2014 “Selection of an Aquaculture Production System for Farmers in the US Virgin Islands” What do you plan to do during the next reporting period to accomplish the goals? We will develop a home/hobby-scale aquaponic system for Virgin Islanders. The availability of appropriate materials from local vendors is limited and we will design around these limitations. The cost of electricity is also high ($0.54/kWh) and the systems designed will have low energy inputs. We will grow more fruiting crops using management techniques learned in the zucchini production research. These crops will be from the Solanaceae family: peppers, eggplant and tomatoes. We will grow floral crops and evaluate production and economics. Preliminary production studies have been conducted with American Marigolds, Sunflowers and Calendula. Spacing, production period and yield will be determined. Continued economic analysis of production will be made. Profit optimization tools will be used to compare crops grown at different densities and for different time periods.

Impacts
What was accomplished under these goals? Evaluated production of leafy green vegetables in the commercial aquaponic system. Produced kale, collards, Swiss chard and pak choi. Planting density and production period were not previously known for these crops. An economic evaluation was also made with linear programming to maximize revenue and determine optimum product mix. Aquaponic systems have high capital and operating costs and production must be optimized to cover these costs and yield a profit. Seedlings can be transplanted closer together and harvested sooner than in field production because nutrients and water are easily available. The crops studied were spaced at a density of 30 plants per meter square and harvested after a production period of 3 weeks. One main consideration for the short production period was the establishment of pests, aphids and/or white fly, on crops grown longer than 3 weeks. By harvesting mature leaves at 3 week intervals pest populations were kept in check. Data on yield was collected at each harvest. Full heads were harvested for pah choi, leaves were harvested from kale, collards and Swill chard. Basil was harvested by a “cut and come again” technique which trims upper leaves and stems leaving 15 cm of plant to regrow. Production was evaluated on a kilogram per square meter basis. Value of each crop per kilogram was obtained from a survey of grocery stores and production value per square meter was calculated. These values were then converted into value per week which allows comparison to crops with different production periods. Variety Density (plants/m2) Growth Period (weeks) Product Yield (kg/m2) Value ($/kg) Value ($/m2) Value ($/m2/week) Pak choi 30 3 Head 8.00 3.30 26.40 8.80 Kale 30 3 Leaf 0.89 6.59 5.86 1.95 Collards 30 3 Leaf 0.45 6.59 2.96 1.48 Swiss Chard 30 3 Leaf 1.44 6.59 9.49 3.16 Basil 16 4 Stem and leaf 1.80 22.05 39.60 9.90 Evaluated zucchini production in the commercial aquaponic system. Some fruiting crops have difficulty with fruit set because of improperly balanced nitrogen and phosphorus. Zucchini also has some marketable fruit loss because of Blossom End Rot, a condition of insufficient calcium. The purpose of this study was to quantify zucchini production when foliar sprayed with different levels of calcium and phosphorus. To determine the effect of calcium on the zucchini production we look at both the marketable and nonmarketable production. In the calcium group, five set of plants were treated including a control group that was not treated. The application rates of 0.0 (control), 1.25, 2.50, 3.74 and 5.0 mg/l where applied weekly to the plant leaf surfaces. The plant that was sprayed with a 3.75 mg/l concentration of calcium was most effective and had a great production of zucchinis, 33.9/m2 for the production period. The control group however produced a high amount of unmarketable zucchinis (28.5/m2). The marketable yield mass of 7.5 kg/m2 with the 3.75 concentration was most effective. The same method was used to determine the effect of different levels of phosphorus on the zucchini plants. Five sets of plants were used for this experiment including a control group. The application rates of 0.0 (control), 0.5, 1.0, 1.5 and 2.0 mg/l where applied weekly. The plant that received the 1.00 mg/l concentration of phosphorus was most effective and had a great production of marketable zucchinis. It also yielded the highest mass (7.4 kg/m2). The plant that received 0.50 mg/l concentration of phosphorus was yielded the greatest number of unmarketable zucchinis. Foliar application of both calcium and phosphorus was effective in elevation production number and mass for zucchini grown in an aquaponic system. Future research will evaluate combined nutrients to further enhance production.

Publications

  • Type: Journal Articles Status: Awaiting Publication Year Published: 2014 Citation: Selection of an Aquaculture Production System for Farmers in the US Virgin Islands Aquaculture America 2014


Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: Evaluated thirteen (13) varieties of cucurbit crops in the UVI commercial aquaponic system. Production data and characteristics were measured. Yield per square meter is the main consideration for farmers, in terms of number and mass, the marketable yield. Finding the most productive crop will allow farmers to maximize their profits. The selection of varieties included cucumber, luffa, gourd and melon. Plants from the Malvaceae family were produced in the aquaponic system in the fall season. Jute and roselle were grown. Jute is a fiber crop and its production showed opportunity to grow non-food crops in the aquaponic system. Farmers who wish to recover aquaculture waste as plant nutrients yet not be concerned about plant quality for consumption would be interested in producing jute. The other Malvaceae crop, roselle, Hibiscus sabdariffa, produces a calyx which is valued during the Christmas season. Producing a seasonal crop with high cultural value, adds value to a farmer's production. Production information is presented at each UVI Aquaponics Workshop. PARTICIPANTS: Aquaponics Program staff, Horticultural Program staff and students. TARGET AUDIENCES: Aquaponic producer community and Caribbean farmers PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The UVI Commercial Aquaponic System was used for this research. Fish were stocked in the rearing tanks and fed and reared according to standard protocol for the duration of the work. Amata 765 cucumber (Chia Tai Seed Co., Thailand) yielded the largest fruits, 393 g/fruit, and the highest count, 159 over a production period of 4 weeks. Bitter gourd (Chua Yong Seng Seed Co., Thailand) yielded the most (17) and largest (449 g/fruit). The roselle variety Trinidad & Tobago Black produced the largest yield (3.2 g/m^2) and individual calyx size (11.1 g).

Publications

  • No publications reported this period