On July 18th the OUTPACE research team went out to the UAB Community Gardens. Our goal was to scout for infected plant leaves, mainly with viral infections, and to test if these plant leaves in fact contain pathogens on them. We were split into three different teams and were assigned to find specific diseased plant leafs. Group one was assigned cucumbers, squash, and watermelon. Group 2 would search for tomato, pepper, eggplant, and potato leaves. Group 3 was assigned Bean leaves. A packet with images of each plant’s diseased leaves was given to us.
Students collecting diseased plant samples
Finding the diseased plants turned out to be harder than we expected. We expected the plants to have blemishes, yellowing, withering, etc. However, many of the leafs with such signs were often accompanied by fungal and oomycetes infections as well as bacterial infections. There was also a lot of insect damage on the plants.
A pepper plant with visible white spots indicating a plant fighting a virus infection.
Bean leaf that tested positive for Poty buffer and the lot it was taken from.
When the students collected possible diseased plant leafs it was time to test them using the Adgia plant pathology kits. Small pieces of infected leaves were cut out and placed into an extract pouch between the mesh grid. Then the packet was sealed and the leaf was grounded by pressing an object such as a marker onto the packet where the leaf resides. When the liquid in the packet turned green an immuno strip was placed inside the pocket till it touched the liquid. After 20-30 minutes the results were found.
Much like a pregnancy test this test shows a negative result when one line is present and a positive result when two lines are present. If the test did not show any lines, the test was considered void. After waiting the appropriate time unfortunately many of the students got a negative result. There were two positive results; one from Dr. Mukhtar’s bean leaf and the other from my team’s bean leaf.
Two positive test results for infected bean plants
Although this type of test is fairly limited to specific diseases, it’s still a useful tool in finding a quick way to test if a leaf is in fact infected instead of taking the leaf all the way back to the wet lab. I now feel confident about using a pathology kit to detect viruses present on plants.