Performance of Nine Butternut Squash Varieties in Summer in the U.S. Virgin Islands

Butternut squash (Cucurbita moschata) is a high value vegetable with similar flavor and texture to other Caribbean pumpkin (Cucurbita pepo) varieties. We evaluated the yield potential of nine butternut squash varieties on St. Croix, USVI. The experimental design was a complete randomized block consisting of nine cultivars (‘Waltham Butternut’ [WM], ‘JWS 6823 PMR’ [JW], ‘Metro’ [MO], ‘Hunter’ [HR], ‘Honey Nut’ [HN], ‘Nutterbutter’ [NB], ‘Tiana’ [TA], ‘Butterbush’ [BB], and ‘Pilgrim’ [PM]) with three replications. The field was prepared following standard cultivation practices (ploughing, harrowing, and rototilling). Squash were seeded on June 9, 2014 with 0.8 m in-row spacing and 1.5 m between rows for a total of 18,750 plants/ha. Plots were irrigated with 40 cm T-Tape (John Deere, Moline, IL) and fertigated weekly using soluble 20-20-20 fertilizer at a rate of 100 kg N/ha. The first harvest was 71 days after planting (DAP) and final harvest was 98 DAP. All varieties had similar total yield (JW 7,294; TA 7,040; HN 6,529; WM 6,390; PM 5,626; NB 5,301; MO 5,296 kg/ha) except for BB (2,833 kg/ha) (p>0.05). The marketable fruit weight was not different among the nine varieties (p>0.05). HN had the highest sugar content at 11.7 °Bx, followed by MO (8.0 °Bx) and PM (7.2 °Bx). All the other varieties presented the same brix, ranging from 4.7 to 7 °Bx (p<0.0001). TA presented 50% more melonworm moth (Diaphania hyalinata) than the varieties WM, NB, HR and BB (p<0.05). HN had higher leaf miner (Liriomyza sativa) (48) than NB, PM, WM, JW (20-40), and BB. WM, JW, and BB were more tolerant to leaf miner than the other varieties (8-15) (p<0.05). Silverleaf disorder, induced by the silverleaf whitefly (Bemisia argentifolii), was higher on HN, BB and TA (4) than PM (1), not been found on the other varieties (p<0.05). JW had less powdery mildew than HR (p<0.05). Results indicate that all varieties except BB have potential as a high value vegetable crop for St. Croix, USVI.