We have eagerly awaited the 2017 Census of Agriculture to see whether the Eastern Broccoli Project is having an effect. Today, the results were released, allowing us to compare our early effect (2017) with the pre-project baseline. We are happy to see so many more Eastern farms finding a place for broccoli in their crop mix.
One consideration is that broccoli can get too big, and get hollow stem. Growers harvesting in the heat of summer find that making the last nitrogen fertilization four weeks before harvest helps avoid the excessive burst.
Some early varieties are maturing in 50 days in the summer. If you do the math, that means the last nitrogen side dress or fertigation is just three weeks after transplanting. Putting on ~150 lb/ac of nitrogen without burning the plants takes some planning.
Alternaria was widespread in the East this year. Unrelenting rain after mid-August created conditions in the Northeast that were conducive to this normally secondary disease. More important, the strain going around was not controlled by the most commonly used fungicide.
Christy Hoepting conducted a fungicide trial to test both our current fungicide program and new materials. Azoxystrobin (Quadris) is widely used, and a 2014 survey in New York showed no resistance. (Cornell pathologists Meg McGrath and Chris Smart are checking for known and novel resistance in 2018 isolates.)
This year, Tim Coolong reported in August that a Quadris-resistant strain was showing up in Georgia. Christy’s trial showed Quadris failing to control in New York. The good news is that the Alternaria was susceptible to fluxapyroxad and pyraclostrobin, the active ingredients in Priaxor. Priaxor is already labeled for use in New York, except Long Island.
The hot and humid weather with heavy rainfall from remnants of hurricanes during August was the perfect storm for Alternaria leaf spot (ALS) to rage out of control in brassica crops across Western New York in 2018. Cornell Vegetable Program fresh market specialists received several complaints about a disease that caused unsightly lesions on both leaves and marketable portions of brassica plants. When ALS attacks the head of broccoli or cauliflower, it renders them unmarketable. Hoepting visited with a grower who was planning to cut broccoli production by one-third, because he had just lost over 85% of his most-recent 5-acre planting to ALS head rot, a loss of $7,500. She immediately set up an ad hoc small-plot replicated trial on his farm in hopes of finding a fungicide that could control this devastating disease.
By the time the broccoli was ready to harvest, differences among treatments in side-by-side plots were striking. In the untreated check, 98% of the heads were unmarketable due to severe ALS, while the best fungicide in the trial, Merivon (fluxapyroxad and pyraclostrobin) had only 5% unmarketable heads. The fungicides that the grower had been using, Bravo and Quadris (azoxystrobin), resulted in 98% and 49% unmarketable heads, respectively. Commercially available fungicides Switch, Quadris Top and Endura had significantly lower unmarketable heads than Quadris with only 10 to 33%.
Priaxor can be applied at most 2 times sequentially and 3 times total. The only targeted fungicide that can be used with it in a program is Switch (cyprodinil and fludioxonil) because its active ingredients are in different chemical groups (FRAC groups 9 and 12) from those of Priaxor (7 and 11).
If the grower were to adopt a 4-week fungicide program with top-performing fungicides, he could expect to get at least 75% marketable heads. Compared to his Bravo/Quadris program, which only yielded 1470 pounds and net $1,323 per acre, the new program could increase both yield and net profit 5-fold by 5881 pounds and $5,562 per acre, despite a 5-fold increase in cost of fungicides from $44 to $223 per acre. After viewing the fungicide trial on his farm, the grower immediately adjusted his fungicide program to include the most effective fungicides in all of his remaining brassica plantings. He is planning to resume full broccoli production next year with the new fungicide program, which has potential to increase profit by $166,860 in his 30 acres of broccoli. Trial results will be shared with CVP growers over the winter, so all conventional growers can benefit from improved ALS control in their brassicas.
For a 2014 survey showing all 47 isolates being susceptible to Quadris, see Kreis, Dillard and Smart. Plant Disease. http://dx.doi.org/10.1094/PDIS-03-16-0414-RE
Note added January 11: Today at the Southeast Vegetable Conference, Dr. Bhabesh Dutta of the University of Georgia at Tifton showed that the pathogen present in Georgia this year is a different (new) species of fungus that it is not controlled by azoxystrobin. Pathologists around the East are testing isolates from their regions to determine whether this species is the one that cause unusually high losses in the region.
This result is useful in that Dr. Dutta has already identified a fungicide program that should be effective in 2019. If the other azoxystrobin-resistant isolates turn out to be the new species, it mean that there has not been a change in the usual Alternaria.
Are you wondering what the implications of new food safety regulations are for broccoli production? Join Eastern Broccoli Food Safety specialists Chris Callahan, Betsy Bihn, and their colleagues on Monday, May 14 at 2 p.m. EDT for a webinar on “Produce Safety for Broccoli Producers”.
Topics will include:
An overview of produce safety
Coverage thresholds and compliance dates
The Food Safety Modernization Act and Produce Safety Rule
Broccoli-specific produce safety considerations
Overview and feedback on educational material development.
You can register for the webinar using the form below. Registration is not mandatory, but it will help us with planning and make it easier for you to get a direct link to the webinar via email. The form also has room for you to list specific questions that you would like to see addressed during the presentation.
The webinar is geared towards growers, but the information will also be useful to buyers, extension specialists, researchers, and others. Registrants will be emailed instructions for joining the webinar by the day of the event.
One fascinating thing about visiting Southwest Florida farms is seeing their distinctive seepage irrigation system. I had heard it described, but I didn’t really get it until I saw it in action.
Unique soils in Florida have allowed growers there to develop a an effective irrigation system that differs in many respects from what I have seen anywhere else. Sandy soils overlay a hardpan just below the maximum rooting zone. That situation allows lateral seepage of irrigation water over considerable distances with hardly any slope.
One of the significant advantages of this system is less disease. Because all the water stays underground, it is rarer for the foliage to be wet and the humidity, while naturally high, is lower. Thus the conditions for fungal spores to germinate and for hyphae to grow are considerably less common.
A couple other unique features make the system work. First, the land is very flat. Whole fields can be irrigated where the underground water table is maintained at an exact distance below the soil surface on the bed tops. In addition, field are interspersed with vast swamplands that serve as storage for irrigation water. Irrigation water can not only be drawn from these reservoirs, but it is also returned to them at the end of an irrigation cycle.
At the end of February, Project Director Thomas Björkman had a chance to visit Monica Ozores-Hampton’s trial site at the University of Florida’s Southwest Florida Research and Education Center and farmers in nearby Immokalee and Clewiston (between Lake Okeechobee and the Everglades).
The SWFREC has seven new faculty, which really adds energy. Like elsewhere in Florida, managing citrus greening is a big priority.
The research station has recovered from Hurricane Maria last fall, with some new greenhouse facilities replacing ones lost. The fields at the station are set up to use the distinctive seepage irrigation system common in parts of Florida that have sandy soils with a hardpan. The crop in the Yield Trial is growing well and should produce good results for spring. The February days were 85°, so warmer spring weather will definitely test the adaptation of these hybrids.
Vegetable farms in SW Florida are generally larger than elsewhere in the East. The smallest farm we visited raises a thousand acres of green beans and sweet corn. The land costs are moderate, and the sandy soil can be managed with appropriately scaled equipment. At this scale, vegetables reach large-scale buyers through the most prominent of eastern produce distributors.
The farms we visited all know very well how to raise broccoli efficiently. The bed system means that the plant populations are lower per gross acre than solid stands. Nevertheless, the yields have been good, pests are uncommon, and the labor has been available for harvest.
The main limitation has been access to markets. The growers noted some irony in being unable to interest south Florida buyers in local broccoli, but finding buyers in New York appreciated getting winter broccoli from closer by. A good relationship between buyers and sellers appears to allow many efficiencies that improve product quality and reduce costs.
Powell Smith, a founding member of the Eastern Broccoli team, recently retired from his position as Horticultural Program Team Leader for Clemson Extension to spend more time outdoors beyond the vegetable field. An entomologist with experience in industry and academia, Powell brought insights about southeastern agriculture and the agricultural community to the Eastern Broccoli project and served as lead for project-related Yield trials and outreach in South Carolina. Those responsibilities now transfer fully to Brian Ward, who has been working with Powell since 2016. No word yet on whether Brian will continue Powell’s habit of sharing sunny South Carolina weather reports with snowbound colleagues up north.
We thank Powell for all of his contributions to the Eastern Broccoli Project and wish him a long and joyful retirement. Happy kayaking, Powell!
The Eastern Broccoli Project recently expanded its Quality trial network to include a site in the important winter growing region of northeastern Florida. Lincoln Zotarelli oversees Quality trial plantings that run from October through April at the University of Florida’s Institute of Food and Agricultural Sciences (UF/IFAS) Hastings Agricultural Extension Center (HAEC).
The Hastings location is differs from other Quality trial sites not only in the timing of its production season, but also in the way in which water is managed. The very sandy soils in this region are separated from the underlying aquifer by a clay hardpan that sits within a few feet of the soil surface. This arrangement allows seepage irrigation to deliver water to plants from below the soil surface through the precise management of water table levels. All other Eastern Broccoli Quality trial sites rely on drip or overhead water delivery.
Florida Quality trial plantings this season were transplanted in early October 2017, early December 2017, and mid-February 2018. All three plantings included the same 31 broccoli hybrids that were rated at the four other Quality trial sites (in South Carolina, North Carolina, New York, and Maine) in 2017. Evaluations are complete for the first planting and in progress for the second planting (Photo 1, above). The third planting (Photo 2, at bottom) will undergo evaluation in early spring 2018.
The Hastings trial has already drawn public attention. In November, a group of 30 Florida elected officials touring grower farms in the Tri-County Agricultural area stopped by the UF-HAEC and, as part of their visit, heard a presentation on the Eastern Broccoli project and the importance of the broccoli industry to the northeast Florida economy. In December, an overview of the broccoli project and its efforts to identify new cultivars adapted to Florida conditions was presented to and discussed with 34 attendees of the station’s 2017 Cole Crop field day.
The Hastings site conducts the last set of plantings in the 14-month Eastern Broccoli Quality trial cycle that begins in February of the previous year. Already, the next Quality trial cycle has begun in Charleston, SC, where seed for a new set of trial entries was sown in February for transplant in mid-March.
The US Vegetable Laboratory in Charleston, SC received a visit this past August from Secretary of Agriculture Sonny Perdue, who toured the facility and expressed his support for agricultural research, including the Eastern Broccoli Project.
The clip below, from RFD-TV via YouTube, shows some highlights from the tour. Our colleague Mark Farnham, who heads the broccoli breeding program at the Lab, appears in several shots. Quality trial leader and Clemson CREC Research Scientist Brian Ward supplied the broccoli seedlings and rating charts shown at 1:31, and Ward can be seen discussing the project with Purdue at 2:02.
All three Eastern Broccoli Quality trial plantings in Maine are in the ground and have held up well in the face of changeable conditions this summer. The trial is running at Highmoor Farm in Monmouth, Maine. Transplant dates were June 16, June 27, and July 19.
Rainfall is again an issue this year. From May 14 through August 16, the farm received only 4 inches of rain, about a third of the average amount. Fortunately, soil moisture was very high at the beginning of the season, and each planting has been drip-irrigated twice. Trial leader Mark Hutton reports that the quality of the trial is excellent.
The Quality trial was open for observation during a late July field day at Highmoor Farm. Thirty vegetable growers viewed the plots. The group also included the director of a regional produce distributor interested in expanding the quantity of broccoli procured from small to medium size New England farms.
Evaluations of broccoli in the first planting began on August 1. Many of the entries in that planting are now past maturity. Broccoli in the second planting should be ready for rating from late August through early September. Broccoli in the third planting is expected to produce mature crowns by mid-September.
"Developing an Eastern Broccoli Industry through cultivar development, economically and environmentally sustainable production and delivery" is supported by the Specialty Crop Research Initiative of the USDA National Institute of Food and Agriculture, under Award No. 2016-51181-25402.