Date of Graduation


Document Type


Degree Name

Master of Science in Crop, Soil & Environmental Sciences (MS)

Degree Level



Crop, Soil & Environmental Sciences


Jarrod T. Hardke

Committee Member

Trenton L. Roberts

Second Committee Member

Jason K. Norsworthy

Third Committee Member

Michael D. Richardson


Midsouth producers, rice, rice seeding, planting arrangements, rice grain yields, crossed planting


Direct-seeding is the most frequently utilized planting practice in Arkansas and Mid-South rice (Oryza sativa L.) production. Enhanced plant density and more rapid rice canopy formation may result from the implementation of innovative plant arrangements and spacings. Studies were initiated in 2019 and continued into 2020 to examine different cultural management practice experiments, including evaluating the impacts of planting arrangement, row spacing, and seeding rates on rice stand density, canopy coverage, grain yield, and milling yield. These small-plot trials were conducted at two locations, a silt loam site and a clay site, representative of soils produced to rice in eastern Arkansas. Stand counts were taken on rice plants in each study at the V2-V3 leaf growth stage. Canopy coverage formation was evaluated in the planting arrangement study by photographing each plot at both locations. Beginning at the V5 growth stage, three sets of canopy coverage images were captured approximately seven days apart. In the pureline variety Diamond, the highest percent canopy coverage was with the highest seeding rate. For each lower seeding rate, the percent canopy coverage was lower. In hybrid cultivar RT XP753, the highest seeding rate resulted in at least 4.48 percentage points greater canopy coverage than the 108, 75, and 43 seeds m-2 seeding rates. The results of this study suggest that there is potential for rice grain yield increase with a crossed planting arrangement, but it is not yet known if that is an economically sound decision. Results from the row spacing study indicate that a narrower rice row spacing higher grain yield is obtained. Further evaluations, including additional row spacings, are necessary to determine the ideal row spacing for maximum yield potential of common cultivars planted today.