Assessment of Basil Varieties for Production in the UVI Commercial Aquaponic System

Basil is a fast-growing crop on aquaponics systems. Previous research has indicated that basil is a high cash-value for aquaponics, and the evaluation of specie adaptation in tropical conditions is mandatory to recommend new varieties for the UVI Commercial Aquaponic System. Two trials were conducted to assess different basil varieties for production in aquaponics. In the first trial (Summer 2015), we evaluated five basil varieties (‘Genovese’, ‘Spicy Globe’, ‘Lemon’, ‘Purple Ruffles’ and ‘Red Rubin’), on a CRD with four replications. In the second trial (Fall 2015), we evaluated seven varieties (‘Genovese’, ‘Spicy Globe’, ‘Lemon’, ‘Purple Ruffles’, ‘Red Rubin’, ‘Cinnamon’ and ‘Thai’), on a CRD with three replications. In both trials, 3-week old seedlings were transplanted in net pots at a density of 16 plants/m². The first trial was harvested every 28 days, and the second trial was harvested before blooming, ranging from every 21 to 28 days. Plants were harvested four times by “cut and come again”, in which stems were cut 15 cm above the root and allowed to regrow until the next harvest. Two plants were harvested to determine fresh and dry mass. In the first trial, ‘Spicy Globe’ (12.11 kg/m²) and ‘Genovese’ (11.36 kg/m²) presented the highest total yield and ‘Purple Ruffles’ the lowest (3.49 kg/m²) (p<0.0001). Plant fresh weight followed the same trend, and dry weight was higher on ‘Genovese’ (220.5 g/plant) (p<0.0001). Leaf anthocyanin was higher on the red varieties ‘Red Rubin’ (34.36 ACI) and ‘Purple Ruffles’ (28.35 ACI) (p<0.0001). Chlorophyll content was higher on ‘Genovese’ (48.594 CCI) (p<0.0001). In the second trial, ‘Genovese’ (6.52 kg/m²), ‘Cinnamon’ (5.94 kg/m²) and ‘Spicy Globe’ (5.78 kg/m²) showed the highest total yield and ‘Purple Ruffles’ the lowest (1.48 kg/m²) (p<0.0001). Plant fresh weight followed the same tendency, and dry weight was higher on ‘Cinnamon’ (81 g/plant) (p<0.0001). Leaf anthocyanin differed in all varieties over time, with larger values on ‘Purple Ruffles’ (80.5 ACI) and ‘Red Rubin’ (36.5 ACI) (p<0.0001). Chlorophyll content was a response of variety and plant development, with readings ranging from 12 (‘Lemon’) to 18 CCI (‘Cinnamon’) (p<0.0001). On both trials, plant width and height increased over time as expected (p<0.0001). 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.