Dodder Growth Changes Induced by Auxin Through a Tomato Host

Overview

Our research is essential to agriculture and understanding the basic biology of parasitic weeds. We studied growth changes in Cuscuta pentagona by venous connection to host tomato. Two methods that we used included measuring dodder stem length and time-lapse photography of stem movement using a GoPro Hero 4 action camera. Time-lapse video recordings, representing more than 1400 hours of experimental interaction between dodder and its host were watched to gather data. We made different concentrations of IAA (auxin) in an agar media and applied two of each concentration to sandpapered stems of tomato. We used a bridge like system to apply dodder to the juvenile tomato. The system we used involved removing the free-growing stem of Ludwigia peruviana with the haustorium-bearing stem region of Cuscuta pentagona. We took cuttings of Ludwigia peruviana near the treated tomatoes under grow lights and watered as needed. During the beginning of the “searching” behavior, 3 stems created a successful bridge to hosts 6, 7, and 8 in our 2nd trial. This bridging flourished with 9 stems of dodder starting a whipping motion, soon looping far enough to be recognized as circumnutation. A curious observation made during the experiment was that the only three dodder that bridged to tomato occurred in tomatoes with low or no auxin agar treatment. A behavior observed in tomato hosts was the hypersensitive response to haustorial connections. Although it is not yet determined, it is hypothesized to be due to either disease transmitted by dodder or by the haustorium intrusion itself.

Competition history

• AJAS 2020 Category not listed

Related projects

Closest projects by meaning, across every fair and year in the corpus.

Browse more like this

• All Plant Sciences projects
• AJAS Plant Sciences projects
• Every AJAS 2020 project