Assessing the impacts of artificial defoliation on pennycress (Thlaspi arvense)biomass and yield

Pennycress (Thlaspi arvense) is a winter annual weed species found in temperate regions that is being domesticated as a new winter cover crop and biofuel species in the Midwest of the United States. However, the response of pennycress to different stressors, including insect pests, is still poorly understood. Artificial defoliation has been used successfully to assess potential impacts of insect pests for various crops. Over two years, we assessed the impacts of artificial defoliation on pennycress biomass and yield. Field-planted pennycress was assessed in randomized complete block design experiments, with six replications of several treatments comprised of combinations of defoliation levels and timings. The defoliation levels included 25%, 50% and 100%. The timings included early (vegetative rosette), intermediate (early flowering) and late (early pod development), and a non-defoliated control. The results of this study will bring light to pennycress response to defoliation at different timings and can help future development of integrated pest management programs for this new crop.