Sasha Eisenman: In His Natural Environment

For Horticulture Assistant Professor Dr. Sasha Eisenman

Horticulture Assistant Professor Dr. Sasha Eisenman doesn’t have to go far to find research ideas.

“Sometimes it’s just a matter of looking out my window on campus. I started to research Staphylea by seeing it outside and wondering if anyone had ever used its seeds for food or oil,” said Eisenman, who has an extensive background in medicinal plants and medicinal plant chemistry — his research has taken him to some very out of the way places, such as Uzbekistan and Kyrgyzstan. “There are records of the seed oil from a related species in China being used in the production of soap and paint but no one has looked at our native species as a potential perennial source of plant-based oil, and there has been no characterization of the oil from these seeds.”

For Eisenman, the 187-acre Temple Ambler campus provides the perfect backdrop for horticultural research of every type.

“It’s naturally my primary source for plant material. I also use the campus a great deal for soils research and teaching as there are a number of different native soil types — go toward the Rose Valley Creek and it’s derived from sandstone; toward Tannery Run Creek it’s all shale based,” he said. “The campus in an invaluable resource for going out and exploring plants in both natural and cultivated environments throughout every season.

From a practical standpoint, Eisenman said, “our students have unique access to a campus that provides them the opportunity to directly examine, study and interact with the plants they are learning about.”

“They can study traits the plants have evolved to tolerate the conditions, and how they have adapted to survive,” he said. “In terms of instruction, our students are obtaining significant tools for their profession.”

Students and faculty at Temple Ambler also have a new technological tool in the tool box — a $100,000 Gas Chromatograph-Mass Spectrometer (GC-MS). In addition to seed oils, Eisenman is currently using the new equipment to study the aromas of different Salvia species that are planted in pollinator gardens for hummingbirds.

“We want to look at the aroma profile of the plants. Most Salvia species have a fragrance — the culinary herb sage for example is probably the most well known species — but they aren’t necessarily hummingbird attractors,” he said. “We are collecting species and cultivars that are used ornamentally in gardens where the plant chemistry has not been well characterized.”

Concentrations of chemicals, Eisenman said, act as a “plant fingerprint.”

“Characterizing the chemistry will help us to understand what is behind the smell — five species, five different smells. It is the first step towards conducting further research into plant breeding and other biological activities, such as antibacterial and antioxidant activity,” he said. “All of the smells are there for a reason. Most are thought to be deterrents for herbivores and protection from pathogens.”

Eisenman said he has recently been exploring “green roof substrates” for a collaborative study with the Environmental Engineering senior studio and researching the effects of biochar as an amendment for growing herbs in green roof media with Dr. Michael Olszewski, Associate Professor of Horticulture. This research, which is funded by grants from the EPA and the Herb Society of America, has recently been accepted for publication in Horticulture, Biotechnology and Environment.

“We’re examining the physical and chemical properties of the substrate and how the plants respond to varying amendments in a controlled environment, the campus Greenhouse,” he said.

The Greenhouse is, of course, another tremendous resource for faculty and students, Eisenman said.

“Students are conducting hydroponic experiments in class, looking at the plants’ physiological and growth characteristics in response to different nutrient levels. They’ve set up their own floating hydroponic systems in the greenhouse, conducting research in plant productivity,” he said. “The students also conduct research using recirculating hydroponics systems, comparing different crop species under the same nitrogen levels but with increasing levels of salinity. In the latest experiment, Swiss chard grew tremendously while cucumber was the least salt tolerant.