The standard strawberry (Fragaria ×ananassa) production system in Florida uses bare-root transplants with three to five leaves; however, commercial transplants are typically variable in size. The objective of this experiment was to study the effects of transplant crown diameter on the subsequent performance of three short-day strawberry cultivars under central Florida conditions. Trials were carried out during the 2012–13 and 2013–14 growing seasons with six treatments resulting from the combination of three cultivars and two crown diameter categories. Transplants of ‘Florida Radiance’, ‘Strawberry Festival’, and WinterStar™ were sorted into two initial crown diameter size ranges: <10 mm and >10 mm. Treatments were established in a split-plot design with cultivars as the main plot and four replications. Dry plant biomass was collected at 6 weeks after transplant (WAT). Canopy diameter and crown diameter were measured at 6 and 18 WAT and fruit harvest started at 8 WAT. There were no interactions between cultivar and initial crown diameter for any of the measured variables. For early yield, larger crowns led to 46% (3.5 Mg·ha−1) and 38% (3.9 Mg·ha−1) higher early yield than smaller crowns in 2012–13 and 2013–14, respectively. Crown diameters >10 mm also resulted in 18% (23.5 Mg·ha−1) and 27% (17.4 Mg·ha−1) higher total yields in 2012–13 and 2013–14, respectively.
Emmanuel A. Torres-Quezada, Lincoln Zotarelli, Vance M. Whitaker, Bielinski M. Santos, and Ixchel Hernandez-Ochoa
Emmanuel A. Torres-Quezada, Lincoln Zotarelli, Vance M. Whitaker, Rebecca L. Darnell, Bielinski M. Santos, and Kelly T. Morgan
Earlier fall planting dates for strawberry (Fragaria ×ananassa) in west-central Florida tend to promote earlier onset of flowering and fruiting. However, warm air temperatures (>28 °C) can result in excessive growth and runner production. Sprinkler irrigation is a common practice to reduce air temperature in the first 10 to15 days after transplanting, requiring large volumes of irrigation water. An alternative to sprinkler irrigation is the application of crop protectants such as kaolin clay after transplanting. The objectives of this study were to determine the optimal planting dates and to assess the most appropriate establishment practices for strawberry bare-root transplants in Florida. Four establishment practices—10 days of sprinkler irrigation (DSI), 10 DSI + kaolin clay, 7 DSI, and 7 DSI + kaolin clay were evaluated for ‘Florida Radiance’ and Sweet Sensation® ‘Florida127’ transplanted in mid September, late September, and early October in consecutive seasons. For ‘Florida127’, September planting dates increased early yield compared with early-October traditional planting dates, with no difference in total yield. Seven DSI followed by the foliar application of kaolin clay at day 8 was also found to increase early yield compared with 10 DSI for strawberry establishment, with annual water savings of 108.7 mm.
Emmanuel A. Torres-Quezada, Lincoln Zotarelli, Vance M. Whitaker, Rebecca L. Darnell, Kelly Morgan, and Bielinski M. Santos
Florida-produced strawberry (Fragaria ×ananassa) plug transplants (SP) are a potential alternative to bare-root transplants (BR). The adoption of this technology could represent a reduction in water usage for plant establishment and potentially higher early yield, as SP may establish more quickly than BR. Thus, the objective of this study was to evaluate the effect of time in nursery and tray sizes, on early and total strawberry yield for Florida-produced SP for ‘Florida Radiance’, ‘Strawberry Festival’, and Sweet Sensation® ‘Florida127’. Runners from Florida-produced mother plants were collected in mid and late August from 2012 to 2015. SP were grown for either 4 or 6 weeks according to the treatment and established in 30-, 40-, 50-, and 72-cell trays, and compared with BR (control). Additionally, strawberry tips from California were evaluated for SP production. BR consistently had higher early yield than SP, ranging from 36% to 91%, between 2012 and 2016. SP produced the same or higher total yield than BR. Florida-produced SP should be grown for 4 weeks before field transplanting in 50-cell trays based on the results of this study. Furthermore, there was no difference between California and Florida tips for total yield. In all seasons, all SP were established with 20% of the total irrigation water used for the BR. Thus, SP could potentially result in water savings of almost 820,800 gal/acre per season, but the early yield of SP would need to be improved to match BR performance.