The Eastern Broccoli Regional Testing System handles year-round, coordinated evaluations of broccoli hybrids across multiple eastern locations from Maine to Florida. The system incorporates two levels of testing: Quality trials and Yield trials.
New hybrids first enter the system in Quality trials, which assess their ability to produce well-formed crowns under stressful conditions. Each entry is rated with respect to more than a dozen traits that contribute to crown quality, including bead (flower bud) size and uniformity, crown shape, and color, as well as the ability to maintain quality for a few days in the field once mature.
Quality trial entries are evaluated in three plantings per year at each of five locations: Monmouth, Maine; Geneva, NY; Waynesville, NC; Charleston, SC; and Hastings, FL. Two of the plantings are scheduled for warmer, more challenging parts of the growing season, while the third is scheduled for a cooler time that is typically considered ideal for broccoli production. Quality trials are always transplanted, both to conserve limited quantities of seed and to ensure adequate numbers of plants in plots.
Hybrids that perform well in Quality trials advance to Yield trials, which assess marketable yield potential in production settings during challenging parts of the growing season. For each hybrid, trial leaders collect data on the quantity and weight of marketable and unmarketable crowns, notable defects, number of cuts to complete harvest, and field holding time.
Yield trials are conducted at up to 11 locations each year, including northern and central Maine, western New York, southwest Virginia, western North Carolina, inland and coastal South Carolina, south central Georgia, and northern and southern Florida. Most Yield trials are conducted on commercial farms using the host grower’s production methods; two exceptions, in northern Maine and southern Florida, take place on research farms using methods employed by local growers. Most are transplanted, but a few are direct-seeded in regions where that planting method is common.
Changes from 2010-2015:
Quality trials replace the Phase I and Phase II trials conducted during the first five years of this effort. As with Quality trials, Phase I and Phase II evaluations focused on traits that contribute to crown Quality. Phase I trials were conducted to screen new hybrids for eastern adaptation in two plantings per year at each of four trial locations, with one planting during the optimal part of the growing season and the other in a more stressful part. Broccoli hybrids that demonstrated some evidence of adaptation to eastern conditions in Phase I trials advanced to more intensive evaluations in Phase II trials, with each hybrid tested in five plantings spanning the growing season at each of four locations.
Because the quality of new hybrids has improved since the project’s start, the need for screening in Phase I has diminished. Cutting back from five Phase II plantings per season and location to three plantings in Quality trials keeps hybrid seed requirements at a manageable number while still representing multiple environments per site.
Under current funding, a fifth Quality trial location in northern Florida has been added, and three additional traits (tendency to purple under stress, presence of leaves in crown, and stem diameter) have been added to the list of crown attributes evaluated.
Yield trials follow a protocol nearly identical to that used for Phase III trials; the name change simply reflects their purpose. New sites in Georgia and Florida were added to encompass the full range of production regions on the East Coast.
From 2011 to 2015, over 134 new and 27 commercially available broccoli hybrids were screened in Phase I trials, with an additional 6 commercial cultivars serving as fixed checks each year. Forty-five new hybrids and nine commercial cultivars advanced to Phase II trials, which began in 2012; nutrient analysis of all Phase II entries was conducted on samples taken from two plantings at each location each year. Two public hybrids and seven commercial hybrids released after the start of the project were evaluated in Phase III (now Yield) trials from 2013 to 2015.