Submitted to: Research Day Abstracts: Regional Universities Research Day
Publication Type: Abstract Only
Publication Acceptance Date: 9/14/2002
Publication Date: 11/1/2002
Citation: EKPO, J.I., BARTHOLOMEW, P.W., WILLIAMS, R.D. DOES SEED SIZE AFFECT THE RATE OF GERMINATION AND EARLY SEEDLING GROWTH IN HAIRY VETCH?. RESEARCH DAY ABSTRACTS: REGIONAL UNIVERSITIES RESEARCH DAY. 2002. P. 74.
Interpretive Summary: Abstract only
Technical Abstract: In many crops there is a positive correlation between seed size and the rate of germination and seedling establishment. Hairy vetch (Vicia villosa, Roth) is an annual cool-season legume used primarily for soil improvement or for forage. In the Southern Great Plains its growing season is limited to approximately 2 months in fall and 2-3 months in spring, which means that speed and reliability of establishment are important factors determining vetch productivity. Commercial supplies of vetch seeds are highly variable in seed size and this study was undertaken to investigate how seed size might influence the success of establishment of a crop of hairy vetch. The imbibition rates, germination rates and dark seedling growth of hairy vetch were investigated for three categories of seed size, "small" (diameter <2.7mm), "medium" (diameter 3.2-3.4 mm), and "large" (diameter >4.0 mm). All measures were made with seeds or seedlings incubated at a constant 20ºC in the dark. Small seeds imbibed at faster rates than medium- and large-sized seeds, but rate of germination and percentage germination after up to 12 days incubation were lower with small than with medium or large seeds. In dark growth, shoot and root weights increased more rapidly with medium and large seeds, and growth was sustained for a longer duration, than with small seeds. Grading of hairy vetch seeds to remove small seeds (<2.7 mm diameter) will increase germination rate and reduce the risk of seedling loss from deep planting.