8/4/2012 7:00 AM
By Anne Harnish Food and Family Features Editor
LANDISVILLE, Pa. — Biocontrols were the “young, exciting science” on display along with showy petunias, tall begonias and succulent portulacas at the horticulture trial gardens field day last Thursday, July 26, at Penn State’s Southeast Agriculture Research and Extension Center in Manheim, Pa. The flower trials are one of the largest university-led horticultural evaluations in the region.
While whorls of brightly colored blooms were freshened up by an early morning thunderstorm, field day participants learned how the plant industry is developing and using biocontrols in the plant industry.
Biocontrols, or “biological controls,” are part of an integrated pest management (IPM) strategy, in which pests, diseases and weeds are controlled via biological methods instead of chemical sprays. Using biocontrols may mean doing things like introducing a fungus to the greenhouse to decimate unwanted weeds or releasing an insect disease to attack a plant pest such as aphids.
“Ten years ago, these methods weren’t available,” said Penn State Extension educator Steve Bogash at the flower trials. He said that biocontrols use novel forms of action and can persist for long periods.
As new biocontrol products are coming on the market, some are being developed as “colonizers” and can provide control of “truly challenging” pathogens where there was little control available before, such as with verticillium, fusarium and phytophthora, Bogash said.
He said biological fungicides and bactericides have amazing potential to supplement and sometimes replace chemical sprays. Many biocontrols are labeled with a low REI (restricted-entry interval) number, allowing workers to re-enter a greenhouse soon after application, rather than having a long waiting period. He and his interns at the Penn State research farm have graduated to biocontrols and organic procedures because he said they can’t afford to stay out of the greenhouses for 4-5 days for re-entry as other chemical labels require. During harvest time, a high REI interferes with their work.
“We’re going to these softer programs,” Bogash said. “They do more than just coat the plant like with chemicals.”
Many biocontrols are less expensive than chemicals, he said, and work in a more complex way. He explained that with plant growth happening in just a few days, a chemical coating applied to the plant quickly can become ineffective on the new growth.
Bogash described using two biocontrols, Stimplex and Regalia, and described how they provide a complex series of actions to protect the plants.
“I want my growers to stay ahead of problems; not be reactive to them,” he said.
According to “buglady” Suzanne Wainwright-Evans, who consults on pest management for commercial growers throughout the U.S., biocontrols work, but they are used differently from what many growers are used to.
“Don’t give up if it doesn’t seem to work,” she said. She explained that there may be many reasons why a biocontrol might not seem to do well, such as pesticide residues on cuttings or if a problem in the greenhouse is misidentified in the first place. In her work, she gives growers detailed instructions for how to use biocontrols.
“Proper identification (of a pest) is so very important,” she said. “And, starting clean’ is critical.”
According to research, said Wainwright-Evans, many thrips and whiteflies arrive at an operation on new cuttings. Instead of waiting for a problem to develop, she said, “Some people will now wash cuttings with (horticultural) soaps and oils first. The problem will only get worse down the road if cuttings aren’t clean.”
During her lecture, Wainwright-Evans played a series of graphic videos showing how predator bugs parasitize or attack greenhouse pests.
Bogash’s recent preference for biocontrols was influenced by a recent Penn State study of 1,500 home gardeners he said.
“(In the survey) 97 percent said they would prefer to buy horticulture crops organically grown,” Bogash said. The same people were surveyed about what they would do if they thought they might lose a crop, and 40 percent said they would still avoid using chemicals.
“These are your customers,” Bogash said to the nursery growers in attendance. “The market is headed to organic. People don’t want chemicals.”
The Blooming Trials
For the flower trials, 21 plant breeders from around the world enter many of their newly bred and existing plant varieties to the trials to be evaluated by Penn State Extension research staff throughout the growing season. Each plant is treated exactly the same during the season and is evaluated regularly, with the collected data published in the fall on a CD and online for use by nursery owners, plant breeders, landscapers and others.
The flower trials team this year included horticulture professor Rob Berghage, Alyssa Collins, Anne Hawk, Carol Lee Shirk, Steve Bogash, John Stepanchak, Jim Bollinger and Thong Le. An army of master gardeners from surrounding counties assists with the work of potting and daily maintenance of the plants.
“It’s been a team effort, and it’s gone very smoothly,” Berghage said of his first year taking over as director since former director Alan Michael retired in December.
“The trials are self-supporting with the seed companies paying for their entries,” he said. “We try to keep the burden off the (research) farm.”
Berghage said that overall, plant genetics are improving greatly over recent years, especially with certain plants like verbenas, calibrachoas and petunias.
“There is less difference between good and bad ones than in the past. In general, they are all good now,” he said, though he acknowledged that the spreading petunias are getting better each year. He said the calibrachoa “double” blooms were introduced 5-8 years ago, but this year there is more of a “doubling” effect within the flower than before.
“The angelonias were spectacular this year,” Berghage said. “And, the begonias are becoming huge and tall, with tremendous flowers and big leaves.”
There are so many varieties of sweet potato vines coming on the market, Berghage said, that there are now a huge range in leaf shapes, colors and sizes.
Vinca has more trailing types than before, and the pennisetum (grasses) have looked great this year, according to Berghage.
As for geraniums, he said people still like them and probably always will. “It’s a stable crop,” he said.
With the category of hanging baskets, Berghage said that over the last 4-5 years there have been more pre-mixed pots, which are looking better and better each year, as the breeders figure out which ones to grow together based on their habits and colors and watering needs.
“Ten to 12 years ago, growers had to mix their plants themselves,” Berghage said. “Whatever you had leftover, you threw together in a pot. Nurseries don’t have to worry about that anymore.”
Though the overcast day of the trials meant that they were slow to open their flowers, a calibrachoa variety that performed well at the 2010 and 2011 flower trials, Minifamous Igeneration Light Pink Eye, was well on its way to being a top performer this year, according to the evaluations for the year so far.
Supertunia Lavendar Skies, a profusely budded single petunia followed suit, with excellent performances for the last two years and on course for a great showing this year.
Kate Chernich, with the landscape department at Masonic Village, said she and her colleagues were at the trials to evaluate and compare the flowers to their own plantings at the large, landscaped retirement community.
“I always like coming here. It’s exciting to see the plants and compare them to ours,” Chernich said. “I’ve noticed with this year’s weather — early warmth, high heat (which stressed the plants), then high rains, many plants are splitting out.’ ”
Another new nursery owner, in his second year of business in Manheim, Pa., was at the trials to look for plants his consumers would enjoy. He likes to get 10 percent new material each year. If it sells, he gets more.
For those looking for that special 10 percent, the flower trials are the best evaluations in the region. The farm is open to the public every day from dawn to dusk for self-guided tours of the flower trials. Complete plant evaluations will be available in September. Call 717-653-4728 for details.