We conducted small-plot sesame variety trials across North Carolina during the 2024 growing season. The goal of these trials was to evaluate commercial and pre-commercial sesame lines for fit in our state. Not only did we want to understand if yield differences existed among varieties, but also if they matured at different dates.

Trials were planted in Clinton (Horticultural Crops Research Station; HCRS), Salisbury (Piedmont Research Station; PRS), and Jackson Springs (Sandhills Research Station; SRS), NC. Soils in these locations were a Norfolk sandy loam (HCRS), Candor sand (SRS), and Mecklenberg clay loam (PRS). We obtained 14 sesame lines, eight from Sesaco and six from Equinom (Table 1).

One week prior to planting, fields were cultivated, and 50 lbs N/ac (46-0-0, SUPERU® coated urea) and a pre-emergent herbicide (Warrant®) incorporated. Warrant® is not labeled for use in sesame. Fields were arranged in a randomized complete block design with three blocks. We planted during the first and second week of June with a two-row Monosem vacuum planter. Row units were spaced at 30” in HCRS and PRS and 38” in SRS. Each variety was planted in four-row plots measuring 5’ – 6.3’ in width and 32’ – 37’ in length, depending on location. Seeding rate was approximately 1 lb seed/ac or 150,000 seed/ac.

We scouted fields regularly towards the end of the season to determine appropriate harvest time. To do this, we inspected capsules, starting at the top of the plant and moving down, for seeds with a defined black layer (indicator of seed maturity). We considered plants ready for harvest once we observed seed black layer in the top 4” of the main stem. At this point, we applied Sharpen® (2oz/ac) to aid in crop dry down. Once completely dry, we harvested with a Wintersteiger Quantum Plus plot combine.

Though we observed slight differences in flowering time, most varieties matured and were harvested on the same day. The exceptions to this were S3251, 20130_19, ES 108, and ES 203, which matured earlier in SRS and were harvested on 10/23, the remainder of the varieties in that location were harvested on 11/18. All varieties were harvested on the same date in HCRS (11/13) and PRS (11/19).

Yields differed among varieties in HCRS but not in SRS nor PRS (Table 2).

*Yield values followed by the same letter are not significantly different. ↲

In HCRS, ‘21628_19’ was the highest yielding variety following by ‘21640_19’. There was considerable variability among varieties, and thus minimal differences observed. ‘ES 203’ was the lowest yielding variety in HCRS. Although we provide yield results for each variety in PRS and SRS, we caution against making any interpretations, as the varieties were not statistically different from one another.

When combining all three locations we do see differences among varieties (Table 3). The highest yielding variety was 21628_19, following by S3251, S39, S2431, and 21640_19. The lowest yielding varieties were ES 201 and ES 203.

*Yield values followed by the same letter are not significantly different. ↲

The advantage of analyzing the results with locations combined is that we can gain statistical power and account for more environmental variability. These results are generally a better prediction of variety performance across the state.

Yields were overall very low in the three locations. The 2024 growing season was marked with significant challenges including severe early-season drought, following by significant rain, and tropical storm/hurricanes. The heavy and prolonged rains resulted in Cercospera leaf spot, which we believe also reduced yield. This disease can be managed by pre-emptive foliar applications of Tilt® fungicide; however, we were unable to get into the field for appropriately timed applications due to the rain.

When selecting a variety for production, it is important to consult with a representative from the contracting entity (e.g. Sesaco) to discuss variety performance from these trials and seed availability. Some of the lines we evaluated were not yet commercially available in 2024.

We would like to thank the NCDA New and Emerging Crops Program for funding this work (grant no. 24-048-4002) as well as the station staff at the Piedmont Research Station, Horticultural Crops Research Station, and Sandhills Research Station.