ARS | Publication request: Effects of planting depth on field establishment of pennycress and light conditions on seed germination

Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Abstract Only
Publication Acceptance Date: September 11, 2011
Publication Date: September 11, 2011
Citation: Ayala-Diaz, I.M., Marek, L., Isbell, T., Johnson, B., Westgate, M., Gardner, C.A. 2011. Effects of planting depth on field establishment of pennycress and light conditions on seed germination [abstract]. Association for the Advancement of Industrial Crops Conference. p. 3.

Technical Abstract: Pennycress (Thlaspi arvense), is a promising oilseed (36% oil) with potential for biofuels and another industrial uses. A winter annual, it may be feasible for use in Midwestern double cropping systems. However, agronomic and biological issues should be studied in order to understand and overcome practical limitations. The objectives of this study were to determine: (1) the effect of planting depth on emergence and establishment of T. arvense accessions, and (2) light requirements for germination of T. arvense. The experiment to evaluate the effect of planting depth was conducted in Ames, IA, at the North Central Regional Plant Introduction Station in a replicated split plot design, with planting depth treatments as main plot effects. Eight Thlaspi accessions were evaluated at two planting depths, 0.5 inches and surface planting. Flowering and maturation dates, number of plants established, oil concentration, and yield were evaluated. The planting depth experimental results indicate that depth does impact pennycress germination and establishment, and differences were observed for stand counts and yield. However, the magnitude of impact varies between accessions with a range of responses. In order to determine whether the accessions have different light requirements for germination, an experiment was conducted in 20ºC germination chambers under light and dark conditions. Three accessions were evaluated in a replicated design, and germination was scored every three days. The germination experiment indicated accessions are variable in their ability to germinate under dark conditions, where the reduction in germination in dark compared to light germination varies from 30% for the less sensitive accessions to more than 90% for the more sensitive accessions. In conclusion, germination of some Thlapsi accessions is sensitive to dark conditions; probably due to lack of light, limiting phytochrome activation that is responsible and necessary for photo-activation of seed germination. Further experiments should be conducted using pre-treatments to activate the phytochrome. While it may be possible to improve establishment rates under shallow planting depth conditions, producers need reliable production guidance for appropriate planting depth and germplasm that will germinate readily if field conditions at planting result in minor deviations from intended depth.