|DHALIWAL, DALJEET - University Of Illinois|
Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/11/2019
Publication Date: 2/6/2020
Citation: Dhaliwal, D., Williams II, M.M. 2020. Economically optimal plant density for machine-harvested edamame. HortScience. 55(3):368-373. https://doi.org/10.21273/HORTSCI14642-19.
Interpretive Summary: U.S. consumers are demanding domestically produced edamame, and while vegetable growers and processors are eager to compete in this market, basic information on growing the crop is lacking. This work filled a significant void by quantifying plant densities most appropriate for growing popular edamame cultivars in the Midwest. Our research shows that current recommended seeding rates from seed companies are gross over-estimates. The impact of this work is providing the vegetable industry with research-based knowledge to more effectively compete for market share of a food crop that historically has been imported yet is growing in popularity domestically.
Technical Abstract: Consumer demand for edamame, the vegetable version of soybean, has grown the last decade in North America. Domestic production of edamame is on the rise; however, research to guide fundamental crop production practices is lacking, including knowledge useful for developing appropriate recommendations for crop seeding rate. Field experiments near Urbana, Illinois were used to quantify edamame response to plant density and determine the economically optimum plant density (EOPD) of machine-harvested edamame. Crop growth and yield responses to a range of plant densities (24,700 to 395,100 plants/ha) were quantified in four edamame cultivars (AGS 292, BeSweet 292, Gardensoy 42, and Midori Giant) across two years. Plots were harvested with the Oxbo BH100, a fresh market bean and pea harvester. In general as plant density increased, branch number and the ratio of pod mass to vegetative mass decreased, while plant height and leaf area index increased. Recovery, the percent of marketable pods in the machine-harvested sample, varied among cultivars from 86 to 95%. Results identified the EOPD for machine-harvested edamame ranged from 87,000 to 120,000 plants/ha. When considering the effect of seed density on plant morphology, as well as seed costs, harvester efficiency, recovery, and marketable pod yield, edamame EOPDs are considerably lower than seeding rates of up to 344,200 seed/ha recommended in recent publications.