Sugar Beet Variety TRialS 2005

 

 

Clint Shock, Eric Eldredge, and Monty Saunders

Malheur Experiment Station

Oregon State University

595 Onion Avenue

Ontario, OR

 

 

Introduction

 

The sugar beet industry in southern Idaho and eastern Oregon, in cooperation with Oregon State University, tests commercial and experimental sugar beet varieties at multiple locations each year to identify varieties with high sugar yield and root quality. A seed advisory committee evaluates the data each year to select the best varieties for sugar production. This report provides the agronomic practices for the Malheur Experiment Station location of the 2005 trials.

 

Materials and Methods

 

Sugar beet varieties were entered by ACH Seeds, Betaseed, Hilleshog/Syngenta, Holly Hybrids, and Seedex in 2005. Twenty-six varieties were tested in the Commercial Trial, and 34 varieties (including the four commercial check varieties) were tested in the Experimental Trial. Seed was organized by Amalgamated Sugar Company. The sugar beet trials were grown on Greenleaf silt loam with winter wheat as the previous crop. A soil test taken on September 15, 2004 showed pH 7.6, 3.6 percent organic matter, 73 lb available nitrogen (N)/acre in the top 2 ft of soil, 20 ppm extractable phosphorus (P), 404 ppm exchangeable potassium (K), 11 ppm sulfate (SO₄), 472 ppm magnesium (Mg), 123 ppm sodium (Na), 2.5 ppm zinc (Zn), 17 ppm iron (Fe), 11 ppm manganese (Mn), 1.0 ppm copper (Cu), and 0.6 ppm boron (B).

 

The grain stubble was chopped and the field was irrigated and disked, then 20 lb N/acre, 100 lb phosphate (P₂O₅)/acre, 150 lb sulfur (S)/acre, 5 lb Zn/acre, 2 lb Cu/acre, and 3 lb B/acre fertilizer was applied in accord with fall soil sample test results. The field was deep ripped in the fall, and in mid-March it was plowed, groundhogged, and bedded on 22-inch rows with a bed harrow.

 

Nortron^® herbicide was applied preplant at 6 pt/acre and incorporated using the bed harrow on March 31. Both the Experimental Trial and the Commercial Trial were planted on April 6. Seeds were planted using John Deere model 71 flexi-planter units with double disk furrow openers and cone seeders fed from a spinner divider that uniformly distributed the seed. Plots of each variety were 4 rows wide (22-inch row spacing) by 23 ft long, with a 4-ft alley separating each tier of plots. The seeding rate was 12 viable seed/ft of row. Each entry was replicated eight times in a randomized complete block design.

 

On April 14 Counter 15G^® was applied in a band over the row at 7.4 lb/acre. The first irrigation, for uniform germination, was applied on May 5 for 24 hours. The irrigation was followed by 2.7 inches of rain through May 18.

 

Alleys were hoed on May 12. Seedlings were thinned by hand to one plant per 7 inches, and the field was weeded on May 23 and 24.

 

The field was sidedressed with Temik 15G^® at 10 lb/acre on May 24 to control sugar beet root maggot, and recorrugated. The field was irrigated for 24 hours to move the insecticide with the wetting front into the sugar beet seedlings' root zone on May 25. On June 2, urea was sidedressed to supply 180 lb N/acre. The field was cultivated and recorrugated again on June 3 and irrigated on June 7.

 

The field was furrow irrigated with surge irrigation from gated pipe, using a Waterman LVC-5 surge valve (Waterman Ind. Inc., Exeter, CA). Soil moisture was monitored using Watermark soil moisture sensors Model 200SS (Irrometer Co. Inc., Riverside, CA) connected to an AM400 Hansen datalogger (M.K. Hansen Co., Wenatchee, WA) to maintain the soil water potential wetter than -70 centibar at 10-inch depth in the beet row.

 

Headline^® fungicide was applied at 12 oz/acre by aerial applicator on June 14 for control of powdery mildew. A petiole test was taken on June 28 and showed Zn and S were deficient. On June 28, Dithane^® fungicide at 2 lb/acre plus Super-Six sulfur at 6 lb/acre were applied by aerial applicator. On July 1, the field was recorrugated the final time. A petiole test taken on July 10 showed nitrate slightly low at 8,391 ppm, when the sufficiency level was 8,802 ppm, and all of the other nutrients were sufficient.

 

The field was hand weeded on June 30 and again on August 11. Sulfur at 6 lb/acre was sprayed by airplane on August 20 to control powdery mildew, followed by an application of Gem^® at 7 oz/acre on August 25.

 

The final irrigation was on September 19. Visual estimates of curly top virus foliar symptom severity were recorded for each plot in the Experimental Trial and Commercial Trial on September 16 by USDA personnel. The curly top ratings are not presented here, but will be compiled and presented in a separate report.

 

Sugar beets were harvested from the Experimental Trial starting on October 10, then rain prevented harvest on the 11th and 12th, and the harvest was completed on October 13. The Commercial Trial was harvested on October 13 and 14. The foliage was flailed and the crowns were removed with rotating knives. All sugar beets in the center two rows of each plot were dug with a two-row wheel-lifter harvester and weighed, and two eight-beet samples were taken from each plot. Samples were delivered each day to the Amalgamated Sugar Company for laboratory analysis of percent sucrose, nitrate concentration, and conductivity.

 

The root weight data were examined for outliers as is customary for calculations of sugar beet variety data in these trials. Observations more than two standard deviations from the mean for each variety were deleted. Sugar sample data were checked for errors in sugar percentages and conductivity. Any erroneous sample readings were deleted from the data set. The companion samples of all missing or deleted sugar data were good, so no plots were lost.

 

The weight of sugar beets from each plot was multiplied by 0.90 to estimate tare. Sugar concentrations were "factored" by multiplying measured sucrose by 0.98 to estimate the sugar that would have been lost to respiration if the beets had been stored in a pile. The data for each plot with two samples were averaged for analysis. The percent extraction was calculated using the formula:

 

Ext = 250 + [(1,255.2 * Cond) - (15,000 * Sug) - 6,185] / Sug * (98.66 - 7.845 * Cond)

 

where Ext is percent extraction, Cond is the electrical conductivity in mmho, and Sug is the sucrose sugar concentration in percent.

 

Variety differences in yield, sucrose content, conductivity, percent extraction, and estimated recoverable sugar were calculated using least-squares means analysis. Sugar beet performance in both trials was compared to the check varieties ACH Seeds 'Crystal 217R', Betaseed 'Beta 4490R', Hilleshog/Syngenta 'HM 2980Rz', and Holly Hybrids 'Acclaim R'. Reports of previous years' Oregon State University variety trials are available online at www.cropinfo.net.

 

Results and Discussion

 

Early stand establishment was slow and erratic due to cool temperatures and repeated rain storms. Later on, surge irrigation approximately once a week maintained soil water potential wetter than -70 kPa through the growing season (Fig. 1).

 

Curly top virus foliar symptoms appeared earlier and were more severe in the beets this year than they had been in recent years. Powdery mildew infection developed on sugar beet foliage in these trials and in neighboring growers' fields. Curly top disease ratings from the official curly top nurseries are reported in Table 1.

 

Variety results were grouped by seed company for the Commercial Trial (Table 2) and the Experimental Trial (Table 3). Within each seed company's varieties, the varieties are ranked in descending order of estimated recoverable sugar in pounds per acre. The root weights were tared 10 percent, as explained above. The truck loads of border row beets delivered to the Nyssa factory in 2005 from the same field, dug with the same harvester, ranged from 2.1 to 4.3 percent tare, plus 2-3 lb of commingled dirt per ton of beets, so actual yields were probably greater than those reported.

 

Root yield in the Commercial Trial averaged 40.8 tared ton/acre, average sugar content was 16.8 percent, and average estimated recoverable sugar was 11,700 lb/acre. The varieties yielding among the highest estimated recoverable sugar in the Commercial Trial were 'HM2992Rz' with 13,355 lb/acre, 'HMPM90' with 13,326, Beta '8600' with 13,291, SX 'Cascade' with 13,275, Beta '4490R' with 12,883, Beta '4199' with 12,829, Crystal '316R' with 12,762, and 'HM PM21' with 12,738 lb/acre.

 

Root yield in the Experimental Trial averaged 44.5 tared ton/acre, average sugar content was 16.7 percent, and average estimated recoverable sugar was 12,600 lb/acre (Table 2). The varieties yielding among the highest estimated recoverable sugar in the Experimental Trial were Beta '4490R' with 14,532 lb/acre, Crystal '597R' with 14,501, Beta '5YK0028' with 13,999, Beta '3YK0019' (renamed Beta '4910R') with 13,993, 'HM 2998Rz' with 13,592, 'HM 2996Rz' with 13,472, Beta '5YK0027' (renamed Beta '4720R') with 13,453, Crystal '594R' with 13,442, 'HM 2999Rz' with 13,407, and Crystal '599R' with 13,390 lb/acre. For 2006, Beta '2YK0016' was renamed Beta '4216R', and Holly '04HX434' was renamed HH 'Condor R'.

 

 

 

 

 

Figure 1. Soil water potential during the 2005 growing season in the commercial sugar beet trial at Oregon State University, Malheur Experiment Station, Ontario, OR.

Table 1. Curly top virus susceptibility data from the Amalgamated Sugar Company report of the 2005 Experimental and Commercial sugar beet variety trials, Malheur Experiment Station, Ontario, OR.

*Curly top ratings: 0 = no curly top symptoms; 9 = plants killed.

^† A factored combined curly top rating of HM Owyhee, Beta 4490R, and Monohikari.

^‡ US 41 in 2002 and 2003; a factored combined curly top rating of HM Owyhee, Beta 4490R, and HH 125 in 2004; and a factored combined curly top rating of HM Owyhee, Beta 4490R, and Monohikari in 2005.

Table 2. Field performance of commercial sugar beet varieties in the Oregon State University Variety Trial at Malheur Experiment Station, Ontario, OR, 2005.

 

	Root	Sugar	Gross	Conduc-	Extrac-	Estimated
	yield	content	sugar	tivity	tion	recoverable sugar
Variety*	ton/acre	%	lb/acre	mmho	%	lb/ton	lb/acre
ACH Seeds
Crystal 316R	44.60	16.75	14,928	0.706	85.51	286.4	12,762
Crystal 333R	43.09	16.31	14,007	0.789	84.33	275.2	11,811
Crystal 217R	35.10	16.64	11,651	0.739	85.06	283.1	9,907
Betaseed