Let's peek into the science labs this week to see what gardening researchers have discovered lately that affects how we garden:
Spotted lanternfly
Pennsylvania's newest nasty-invader bug is the spotted lanternfly, an attractive-looking bug (so far as bug-cuteness goes) that showed up for the first time in Berks County in 2014.
Spotted lanternflies are colorful, albeit destructive, bugs.
The state Department of Agriculture has extended a quarantine to 13 Pennsylvania counties (including Lancaster and Lebanon) in an attempt to contain this fast-spreading bug. It's also advising the removal of as many of the lanternfly's favorite host trees as possible (the tree of Heaven, which is a weed tree anyway) and asking people to check for lanternfly egg masses on their car tires if they've been in a quarantine county.
Meanwhile, researchers at Penn State University are studying captured bugs in an attempt to figure out ways to stop it, such as by importing predators from the bug's native Asia or by introducing bacteria or other biological controls.
Penn State entomologist Julie Urban is trying to identify exactly what draws spotted lanternflies to trees of Heaven in an effort to develop a lure that might disrupt their mating.
Spotted lanternfly is distinctive for the lower pair of spotted red wings on adult bugs, which hatch in May and congregate on trees (and sometimes people) in July.
Adults pierce trunks, branches and vines, causing a mix of sap and "honeydew" (bug poop) that draws other insects and grows a potentially deadly sooty-mold fungus.
The bug is a particular threat to grapes, fruit trees, and a variety of hardwood trees, including cherry, beech, maple, and walnut.
New meaning for "plant light"
Engineers at the Massachusetts Institute of Technology have created a watercress that dimly glows, opening the possibility that plants could become our lights of the future.
"The vision is to make a plant that will function as a desk lamp - a lamp that you don't have to plug in," says Michael Strano, a professor of chemical engineering at MIT.
Rather than genetically altering plants as other glowing-plant developers have tried, MIT engineers got watercress to faintly glow by using nanoparticles to deliver luciferase (an enzyme) into the plant cells. That's the enzyme that gives fireflies their glow.
Read George's article on the Starlight Avatar, a tobacco plant that glows due to genetic engineering.
MIT's first plants glowed faintly for only 45 minutes, but engineers have boosted that to 31/2 hours. They believe the technology, called "nanobionics," is capable of producing enough light that plants could someday light an office workspace and trees could become self-powered streetlights.
To get the firefly enzyme into the plants, researchers mixed it and silica nanoparticles into a solution, soaked the plants in it, then exposed the plants to high pressure.
Light is just the latest way that embedded nanoparticles have given plants new use. Strano's lab previously designed plants that can detect explosives and monitor drought conditions.
"Plants can self-repair, they have their own energy, and they are already adapted to the outdoor environment," Strano says. "We think (plants that light) is an idea whose time has come."
MIT has managed so far to produce glowing arugula, kale, and spinach in addition to watercress. And researchers have learned that it's possible to "turn off" glowing plants by adding nanoparticles that carry a luciferase inhibitor.
Read more about glowing plants in a Technology Review article.
Is it really a flytrap?
Research by Dr. Stephen Williams, professor emeritus of biology at Lebanon Valley College, provides evidence that the best-known carnivorous plant, the Venus flytrap, isn't much of a fly-eater after all.
A Venus flytrap snaps shut on a cricket.
It's not that this little tropical plant with teeth-lined traps won't capture and digest flies. It's just that it captures flies when those are all that's around to "eat."
Williams compared what Venus flytraps captured in their native habitat to what they captured in greenhouses, where they're most often encountered by people.
He found that in a native habitat, about 70 percent of the flytrap diet is spiders, ants, and beetles. Plants sometimes capture as little as 1 percent flies.
In a typical greenhouse, though, flies make up 90 percent or more of the plant's diet - primarily because flies are plentiful there.
"It's clear from all the studies done in the natural habitat that flies are of minor importance," Williams says, adding that it's debatable whether this plant should even be called a flytrap.
How does "Venus spidertrap" sound?
Williams' research also found that prey often just "blunder" into traps instead of being lured by anything and that Charles Darwin was wrong when he theorized that flytraps released small prey because they weren't worth the digestion energy.
"Traps show little selectivity based on prey size," Williams says.
Beating boxwood blight
Progress is being made on a variety of weapons to overcome the blight disease that's been threatening boxwoods since 2011 in 22 states, including Pennsylvania.
This spotting is an infection of boxwood blight attacking these boxwood leaves.
Researchers at the U.S. Department of Agriculture and Virginia Tech University have found ethanol and ordinary bleach to be very effective in killing the disease-spreading fungal spores. They're also screening microorganisms in hopes of finding one that can naturally kill the blight fungus.
Virginia Tech researchers are trialing assorted mulches, too, to see which are best at keeping soil-borne spores from splashing up to infect plants.
And, Connecticut Agricultural Experiment Station researcher Dr. Jim LaMondia has identified several already-available fungicides that effectively prevent blight on boxwoods, including common chlorothalonil (Daconil). He found that propiconazole is particularly effective.
Meanwhile, breeders are working on new boxwood varieties that are naturally blight-resistant. 'Golden Dream,' 'Green Beauty' and 'Nana' are three varieties already on the market that North Carolina State University researchers have identified as being the most blight-resistant.
Boxwood blight progresses quickly once spores infect a plant, usually in mid to late summer. Leaves get spots and then brown and drop.
English and American boxwoods are particularly susceptible.