Oakes Irrigation Research Site
Carrington Research Extension Center * North Dakota State University
P.O. Box 531, Oakes, ND 58474-0531, Phone: (701) 742-2744, FAX: (701) 742-2700, E-mail:												Kelly.c.Cooper@ndsu.edu
Optimizing Fungicide Application Methods for Management of Sclerotinia Head Rot of Sunflowers
M. Wunsch, B. Kraft, M. Schaefer and S. Kallis, K. Cooper, L. Besemann and H. Eslinger
Methods
General Agronomics: The study was on a Maddock and Embden sandy loam soil type.  The previous crop was spring wheat (replicate 1) and soybeans (replicates 2, 3 and 4).  The tillage operation consisted of disking once in the fall and spring cultivations (May 2, May 27 and June 1) to remove small weeds and to smooth the seedbed.  Supplemental fertilization:  19.4 lbs N, 49.8 lbs P, 45 lbs K, and 10.4 lbs S were applied on April 21.  On June 24, nitrogen (applied as 28-0-0) was side-dressed at 60 lbs/ac.  Authority Elite (sulfentrazone, 0.7 lb ai/gal, and s-metolachlor, 6.3 lb ai/gal; FMC Corp., Philadelphia, PA) was applied pre-emergence at 22 fl oz/acre on June 3.
Experimental design: A completely randomized split-plot design with inoculation treatment (inoculated at R5.1-R5.3, inoculated at R5.4-R5.6, and inoculated at R5.7-R5.9) as main factor and fungicide application treatment as sub-factor with four replicates.
Planting details:  NuSeed 'Jaguar DMR' sunflowers were planted on June 2 using a Monosem planter.  The final plant population was 17,500 plants/acre.  To ensure consistent plant spacing, sunflowers were over seeded, and the final plant population of 17,400 plants/acre was accomplished by manually thinning the sunflowers.  Sunflowers were thinned at the V4-V5 growth stage on June 27.
Fungicide applications:  Fungicides were applied (1) through standard boom-mounted nozzles spaced 20 inches apart on a tractor-mounted boom or (2) through drop nozzles spaced 30 inches apart on a tractor-mounted boom.  In treatments utilizing drop nozzles, the tractor was driven such that the drop nozzles were centered between rows.  The water volume for all treatments was 15 gal/acre.
Flat-fan nozzles mounted directly on the boom:  TeeJet XR8001VS flat-fan nozzles (Spraying Systems Co.; Glendale Heights, IL) were spaced 20 inches apart on the boom.  Applications were made at 40 psi, and the boom was positioned such that it was 18 inches above the center of sunflower heads, the height at which spray patterns from adjacent nozzles meet without significant overlap.  Applications were made in an eastern direction (90˚ from north) to half of the plots and in a western direction (270˚ from north) to half of the plots.  Droplet sizes were ‘fine’ and application speed was 2.0 mph
Flat-fan nozzles mounted on '360 Undercover' drop nozzles:  TeeJet XR11001VS flat-fan nozzles (Spraying Systems Co.; Glendale Heights, IL) were attached to the side ports of the 360 Undercover drop nozzle (360 Yield Center; Morton, IL).  Applications were made at 40 and 60 psi (tested as different treatments), with the boom positioned such that the flat-fan nozzles were centered at the mid-point of the sunflower heads and the flat-fan spray pattern was vertical.  This nozzle setup was tested at 40 and 60 psi in each of two driving directions:  west, 270˚ from north; and east, 90˚ from north.  Droplet size was fine at 40 psi and very fine at 60 psi.  Driving speed was 2.6 mph at 40 psi and 3.2 mph at 60 psi.
Hollow-cone nozzles mounted on '360 Undercover' drop nozzles:  ConeJet VisiFlo TX-VK3 hollow-cone nozzles (Spraying Systems Co.; Glendale Heights, IL) were attached to the side ports of the 360 Undercover drop nozzle (360 Yield Center; Morton, IL).  Applications were made at 60 psi with the boom positioned such that nozzles were centered at the mid-point of the sunflower heads.  This nozzle setup was tested at 60 psi at each of two driving directions:  northwest, 313˚ from north; or southeast, 133˚ from north.  Droplet size was very fine and driving speed was 1.6 mph.
Fungicide application details:  August 5 at 11:30 am to 3:30 pm; temperature = 77 to 84˚F, relative humidity = 41-52%, wind speed = 3 to 6 mph; 97% of sunflowers were in bloom (ray flowers open) and 3% had not yet entered bloom; average growth stage = R5.6.  Average height of the sunflowers (to the middle of the head) was 80.2 inches.  Neither rust nor Sclerotinia head rot were observed.  Sunflower growth stage was assessed immediately before applying fungicides by evaluating 5 plants at 12 arbitrarily selected locations across the trial.
Inoculation methods – R5.1 to R5.3 inoculation timing: Inoculations were conducted over multiple days such that every head was inoculated at R5.1 to R5.3 (10 to 30% of the disk flowers blooming or already bloomed).  In each inoculation, approximately 30,000 spores were delivered through three squirts of the spray bottle.
Assessment of fungicide deposition:  Fungicide spray deposition to the front of sunflower heads was assessed using 2 in. x 3 in. TeeJet Water-Sensitive Cards (Spraying Systems Co.; Glendale Heights, IL).  Lengthwise, all treatment plots were separated from adjacent treatment plots by a 30-foot-long buffer plot, and spray deposition was assessed on sunflowers within the buffer plot immediately adjacent to the treatment plot.  Spray deposition was evaluated for six arbitrarily selected sunflower heads per plot.  A 3 inch by 5 inch index card, placed inside a zip lock bag, was secured to the front of the sunflower head with a rubber band to provide a dry, flat surface for mounting the water-sensitive spray card.  Paper extensions were taped to the backs of the spray cards to facilitate attachment of spray cards to the bagged index cards without interference with the water-sensitive surface of the spray cards, and paper clips were used to secure the spray cards to the bagged index cards.  The water sensitive cards were placed on heads immediately before fungicides were applied.  They were removed after applications as soon as the water-sensitive surface had dried and were stored in a paper bag placed within a sealed container with a desiccant.  The spray cards were scanned at 600 pixels per inch resolution.  To avoid bias caused by any background discoloration in the spray cards caused by ambient humidity at the time fungicides were applied, the lightest shades were removed from the cards; images were opened in Photoshop CS6, converted to grayscale, and all pixels within the 0 to 100 range of intensity (on a 0 to 255 intensity scale, where 0 = white and 255 = black) were converted to 0.  Additional edits were manually conducted as needed to eliminate any biases associated with smudging and handling errors.  Analysis of the edited grayscale images was conducted in DepositScan (Zhu et al. 2011; Computers and Electronics in Agriculture 76:38-43).  Only percent coverage results are reported; due to the positioning of sunflower heads relative to the sprayer, the spray cards were often not perpendicular to the spray direction, making it difficult to rigorously assess droplet sizes or droplet volumes on the basis of the deposition patterns on the spray cards.
Disease establishment: Spore solutions were prepared by adding laboratory-grown ascospores of Sclerotinia sclerotiorum to non-chlorinated water and adding a one to two drops of Tween 20.  Hand-held spray bottles were calibrated to determine how much liquid was released through each squirt of the bottle, and the spore solution was adjusted so that each squirt of the spray bottle delivered approximately 5,000 spores.  In each inoculation, 15,000 spores were delivered to the front of each head (3 squirts of the spray bottle).  Each head was inoculated once.  At each inoculation, 15,000 spores were applied to the front of each head.
Inoculation methods – R5.7 to R5.9 inoculation timing: Inoculations were conducted over multiple days such that every head was inoculated at R5.7 to R5.9 (70 to 90% of the disk flowers blooming or already bloomed). In each inoculation, approximately 30,000 spores were delivered through three squirts of the spray bottle. Supplemental overhead irrigation was applied to this trial through a micro-sprinkler misting system, with the frequency and intensity of irrigation adjusted relative to weather conditions.
Inoculation timing 1 - R5.1 to R5.3:  Inoculations were conducted on August 1 and August 3 (4 and 2 days before fungicides were applied, respectively) such that every head was inoculated once at the R5.1 to R5.3 growth stage (10 to 30% of the disk flowers blooming or already bloomed).  When plants were inoculated an upper leaf was marked with a spray-paint dot to indicate that inoculation was completed.
Inoculation timing 2 - R5.6 to R5.9:  Every head was inoculated on August 6 (1 day after fungicides were applied).  The predominant growth stage was R5.6 to R5.9, and the average growth stage was R5.8.
Inoculation timing 3 - R5.8 to R6.0:  Every head was inoculated on August 8 (3 days after fungicides were applied).  The predominant growth stage was R5.8 to R6.0, and the average growth stage was R5.9.
Irrigation:  Overhead irrigation was applied through micro-sprinkler misting systems from August 1 to 25 for 3 minutes every 30 minutes during daytime hours or as needed to keep the front of sunflower heads moist.
In-season notes
Disease severity:  On September 21-22 at the R9 growth stage every plant was assessed for the percent of the head exhibiting Sclerotinia head rot.  All plants in each plot were evaluated.
Sclerotinia head rot:  On September 21-22 at the R9 growth stage every plant was assessed for the percent of the head exhibiting Sclerotinia head rot.  All plants in each plot were evaluated.
Harvest and seed yield and quality assessment:  To facilitate harvest before significant bird predation occurred, sunflower heads were manually clipped and bagged on September 27 at the early R9 growth stage, placed in a drier, and then passed through a combine.  Yields were calculated on the basis of the measured plot lengths.  Seed moisture and contamination with sclerotia were assessed, and yield data were adjusted to a standard 10% moisture and to report seed yield excluding sclerotia.  Several severe wind and rain storms occurred during August, resulting in significant lodging in some plots.  Heads were only harvested from plants that had not lodged.
Sclerotia in harvested grain:  Percent sclerotia (by weight) was assessed by manually removing all sclerotia from a 200-gram subsample of harvested grain from each plot.
Sclerotia in cleaned grain:  Percent sclerotia (by weight) that could not be mechanically separated on the basis of size was assessed by manually separating all sclerotia from a subsample of grain that had been cleaned by passing it through a shaker equipped with an upper sieve with 30/64 round holes and a lower sieve with 7 x 3/4 slotted holes.
Yield assessment:  Yields were adjusted by the percent sclerotia in the cleaned grain such that reported yields represented excluded all sclerotia contamination.  Test weights were evaluated on a subsample of grain from which all sclerotia were manually removed.
Statistical analysis: Data were evaluated with analysis of variance.  Assumptions of ANOVA:  (1) The assumption of constant variance was assessed with Levene's test for homogeneity of variances and visually confirmed by plotting residuals against predicted values.  (2) The assumption of normality was assessed the Shapiro-Wilk test and visually confirmed with a normal probability plot.   (3) The assumption of additivity of main-factor effects across replicates (no replicate-by-treatment interaction) was evaluated with Tukey's test for nonadditivity.  All data met model assumptions except the head rot incidence and severity index data within the non-inoculated treatments.  To address these distributional problems, a systematic natural-log transformation [LN(x+1) for data sets that include values less than 1.0] was applied to these data.  All other data met model assumptions.  Within each inoculation treatment, analyses of fungicide application treatments were conducted with replicate and treatment as main factor effects.  Combined analyses:  Combined analyses of (1) fungicide application treatments across inoculation treatments and (2) inoculation treatments across fungicide application treatments were conducted with replicate and irrigation treatment as main-factor effects and seeding rate & foliar fungicide treatment as a sub-factor and controlling for replicate by main-factor and main-factor by treatment interactions.  F-tests for the combined analysis of the main factor (inoculation treatment) and the sub-factor (fungicide application method) were conducted utilizing replicate-by-main-factor interaction for the error term.   Treatment contrasts:  Single-degree-of-freedom contrasts were performed for all pairwise comparisons of treatments; to control the Type I error rate at the level of the experiment, the Tukey multiple comparison procedure was employed.  Software used for analyses:  Analyses were implemented in PROC UNIVARIATE and PROC GLM of SAS (version 9.4; SAS Institute, Cary, NC).
FUNDED BY A USDA SPECIALTY CROP BLOCK GRANT AND A GRANT FROM THE USDA NATIONAL SCLEROTINIA INITIATIVE
Inoculations were conducted (1) August 1 and 3 such that each head was inoculated once at R5.1 to R5.3, (2) August 6 when sunflowers were at predominant R5.6 to R5.9, or (3) August 8 when sunflowers were at predominant R5.8 to R6.0.  Fungicides were applied August 5.
								Fungicide		Sclerotinia head rot						Rust		Yield		Test Wt.		Kernel Wt.		Sclerotia in		Sclerotia in		Dehulled		Seed over		Seed over		Seed through
	Nozzle	Spray	Nozzles utilized	Application	Droplet	Driving	Driving	Coverage		Incidence (%)		Severity (%)		Sev. Index (%)				10% moisture						harvested grain		cleaned grain		kernels		23/64 sieve		22/64 sieve		20/64 sieve
	Placement	Pattern	(Spraying Systems TeeJet)	Pressure	Size	Speed	Direction	%		-  Sept 21-22   |   R9 growth stage  -						Sept. 15; R8		lbs/ac		lbs/bu		seeds/lb		% by weight		% by weight		%		% by weight
1	Non-treated control									76	c*	100	a*	76	c*	6.3	b*‡	899	c*	21.5	a*	3492	a*	12	a*	7	a*‡	2	a*‡	28	a*	47	a*	14	a*
2	Boom-mounted nozzles	flat fan	XR8001VS at 20-inch spacing	40 psi	Fine	2.0		0.2	b*‡	62	b	100	a	62	b	0.1	a	1273	abc	22.2	a	3413	a	11	a	7	a	2	a	29	a	46	a	17	a
3	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	40 psi	Fine	2.6	East (90˚ from the north)	5.3	ab	70	abc	100	a	70	abc	0.1	a	1549	ab	22.5	a	3293	a	11	a	7	a	4	a	28	a	48	a	16	a
4	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	40 psi	Fine	2.6	West (270˚ from the north)	2.2	ab	70	abc	99	a	70	abc	0.0	a	985	bc	22.1	a	3535	a	11	a	7	a	2	a	32	a	49	a	15	a
5	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	60 psi	Very Fine	3.2	East (90˚ from the north)	3.1	ab	69	abc	99	a	68	abc	0.2	a	1438	ab	21.8	a	3457	a	11	a	6	a	1	a	38	a	55	a	13	a
6	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	60 psi	Very Fine	3.2	West (270˚ from the north)	3.8	ab	74	bc	100	a	74	cb	0.1	a	869	c	21.5	a	3445	a	12	a	8	a	3	a	36	a	55	a	14	a
7	Undercover 360 drop nozzle	hollow cone	TX-VK3 on side ports	60 psi	Very Fine	1.6	East (90˚ from the north)	17.3	a	60	a	100	a	60	a	0.4	a	1618	a	22.5	a	3353	a	10	a	6	a	2	a	35	a	54	a	13	a
8	Undercover 360 drop nozzle	hollow cone	TX-VK3 on side ports	60 psi	Very Fine	1.6	West (270˚ from the north)	7.6	ab	69	abc	99	a	68	abc	0.1	a	1203	abc	21.8	a	3373	a	11	a	7	a	4	a	38	a	56	a	13	a
							F:	2.69		3.13		0.56		3.09		34.49		5.66		2.15		0.93		0.65		1.06		0.98		1.41		1.47		1.00
							P>F:	0.0485		0.0068		0.7879		0.0073		< 0.0001		< 0.0001		0.0507		0.4875		0.7096		0.3999		0.4572		0.2192		0.1956		1.0000
							CV:	69.1		15.3		1.9		15.4		112.5		32.8		4.4		7.3		24.4		15.1		61.5		36.4		22.1		32.4
1	Inoculated at R5.1 to R5.3 with heads inoculated August 1 or 3.									39	a*	99	a*	39	a*	0.9	a*	1630	a*	24	a*	3318	a*	5	a*	3	a*‡	1	a*‡	23	b*	42	b*	19	b*
2	Inoculated at predominant R5.6 to R5.9 (average R5.8) with heads inoculated August 6.									93	b	100	a	93	b	1.1	a	739	b	20	c	3539	a	18	c	11	c	4	a	42	a	59	a	10	a
3	Inoculated at predominant R5.8 to R6.0 (average R5.9) with heads inoculated August 8.									74	b	100	a	74	b	0.7	a	1290	a	22	b	3406	a	10	b	6	b	2	a	35	a	53	a	13	a
							F:			35.76		1.26		35.29		0.45		12.47		32.28		2.27		33.38		32.89		4.71		14.92		22.88		1.00
							P>F:			0.0005		0.3497		0.0005		0.6565		0.0073		0.0006		0.1846		0.0006		0.0006		0.0589		0.0047		0.0016		1.0000
							CV:			3.1		0.6		3.1		34.5		5.7		2.2		0.9		0.7		1.1		1.0		1.4		1.5		1.0
INOCULATED at R5.1-R5.3
Inoculations were conducted August 1 and 3 such that each head was inoculated once at the target growth stage.  Fungicides were applied August 5.
										Sclerotinia head rot						Rust		Yield		Test Wt.		Kernel Wt.		Sclerotia in		Sclerotia in		Dehulled		Seed over		Seed over		Seed through
	Nozzle	Spray	Nozzles utilized	Application	Droplet	Driving	Driving			Incidence (%)		Severity (%)		Sev. Index (%)				10% moisture						harvested grain		cleaned grain		kernels		23/64 sieve		22/64 sieve		20/64 sieve
	Placement	Pattern	(Spraying Systems TeeJet)	Pressure	Size	Speed	Direction			-  Sept 21-22   |   R9 growth stage  -						Sept. 15; R8		lbs/ac		lbs/bu		seeds/lb		% by weight		% by weight		%		% by weight
1	Non-treated control									49	b*‡	100	a*	49	a*‡	5.5	b*‡	1213	a*	23.4	a*	3426	a*	6	a*	3	a*	1.2	a*‡	19	a*	37	a*	20	a*
2	Boom-mounted nozzles	flat fan	XR8001VS at 20-inch spacing	40 psi	Fine	2.0				34	ab	99	a	33	a	0.1	a	1738	a	24.4	a	3325	a	5	a	3	a	0.5	a	19	a	35	a	24	a
3	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	40 psi	Fine	2.6	East (90˚ from the north)			40	ab	100	a	40	a	0.3	a	1829	a	24.4	a	3363	a	6	a	4	a	1.7	a	22	a	39	a	22	a
4	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	40 psi	Fine	2.6	West (270˚ from the north)			41	ab	100	a	41	a	0.0	a	1327	a	23.7	a	3268	a	5	a	3	a	2.1	a	24	a	41	a	19	a
5	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	60 psi	Very Fine	3.2	East (90˚ from the north)			42	ab	97	a	41	a	0.1	a	1705	a	23.3	a	3291	a	6	a	4	a	0.6	a	26	a	47	a	15	a
6	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	60 psi	Very Fine	3.2	West (270˚ from the north)			44	ab	100	a	44	a	0.2	a	1342	a	23.2	a	3326	a	5	a	3	a	1.1	a	28	a	47	a	17	a
7	Undercover 360 drop nozzle	hollow cone	TX-VK3 on side ports	60 psi	Very Fine	1.6	East (90˚ from the north)			23	a	100	a	23	a	0.8	a	2315	a	24.6	a	3211	a	3	a	2	a	1.0	a	26	a	46	a	18	a
8	Undercover 360 drop nozzle	hollow cone	TX-VK3 on side ports	60 psi	Very Fine	1.6	West (270˚ from the north)			37	ab	97	a	36	a	0.1	a	1570	a	23.5	a	3332	a	5	a	3	a	1.4	a	21	a	41	a	17	a
							F:			2.50		0.75		2.41		7.84		1.70		1.77		1.18		1.36		1.54		0.42		1.16		2.00		1.87
							P>F:			0.0493		0.6333		0.0557		< 0.0001		0.1643		0.1471		0.3577		0.2720		0.2094		0.8757		0.3663		0.1030		0.1261
							CV:			9.0		2.9		9.1		113.7		32.2		3.6		3.5		29.9		33.8		88.7		29.7		16.0		22.2
INOCULATED at R5.6-R5.9
Every head was inoculated on August 6; predominant growth stage was R5.6-R5.9, and average growth stage was R5.8.  Fungicides were applied August 5.
										Sclerotinia head rot						Rust		Yield		Test Wt.		Kernel Wt.		Sclerotia in		Sclerotia in		Dehulled		Seed over		Seed over		Seed through
	Nozzle	Spray	Nozzles utilized	Application	Droplet	Driving	Driving			Incidence (%)		Severity (%)		Sev. Index (%)				10% moisture						harvested grain		cleaned grain		kernels		23/64 sieve		22/64 sieve		20/64 sieve
	Placement	Pattern	(Spraying Systems TeeJet)	Pressure	Size	Speed	Direction			-  Sept 21-22   |   R9 growth stage  -						Sept. 15; R8		lbs/ac		lbs/bu		seeds/lb		% by weight		% by weight		%		% by weight
1	Non-treated control									97	a*	100	a*	97	a*	8.8	b*‡	594	a*	19.6	a*	3687	a*	20	a*	12	a*	3	a*‡	34	a*	54	a*	9	a*
2	Boom-mounted nozzles	flat fan	XR8001VS at 20-inch spacing	40 psi	Fine	2.0				94	a	100	a	94	a	0.0	a	613	a	19.6	a	3582	a	19	a	12	a	4	a	42	a	60	a	10	a
3	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	40 psi	Fine	2.6	East (90˚ from the north)			92	a	100	a	92	a	0.1	a	1058	a	20.4	a	3316	a	18	a	9	a	7	a	31	a	54	a	12	a
4	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	40 psi	Fine	2.6	West (270˚ from the north)			95	a	100	a	95	a	0.1	a	576	a	20.5	a	3667	a	19	a	13	a	2	a	33	a	50	a	14	a
5	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	60 psi	Very Fine	3.2	East (90˚ from the north)			92	a	100	a	92	a	0.1	a	998	a	20.0	a	3401	a	17	a	9	a	2	a	53	a	68	a	8	a
6	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	60 psi	Very Fine	3.2	West (270˚ from the north)			95	a	99	a	95	a	0.1	a	283	a	19.9	a	3665	a	16	a	15	a	4	a	48	a	64	a	9	a
7	Undercover 360 drop nozzle	hollow cone	TX-VK3 on side ports	60 psi	Very Fine	1.6	East (90˚ from the north)			93	a	100	a	93	a	0.2	a	973	a	20.2	a	3454	a	17	a	10	a	3	a	44	a	62	a	9	a
8	Undercover 360 drop nozzle	hollow cone	TX-VK3 on side ports	60 psi	Very Fine	1.6	West (270˚ from the north)			89	a	100	a	89	a	0.0	a	779	a	20.7	a	3586	a	17	a	10	a	11	a	51	a	66	a	12	a
							F:			1.26		1.00		1.18		126.95		1.89		0.65		1.11		0.51		0.65		1.65		1.46		1.01		1.18
							P>F:			0.3172		0.4586		0.3540		< 0.0001		0.1282		0.7076		0.3990		0.8191		0.7101		0.1777		0.2392		0.4577		0.3606
							CV:			4.5		0.4		4.6		42.3		42.1		5.4		7.2		20.4		42.2		44.5		33.5		20.9		36.0
INOCULATED at R5.8-R6.0
Every head was inoculated on August 8; predominant growth stage was R5.8-R6.0, and average growth stage was R5.9.  Fungicides were applied August 5.
										Sclerotinia head rot						Rust		Yield		Test Wt.		Kernel Wt.		Sclerotia in		Sclerotia in		Dehulled		Seed over		Seed over		Seed through
	Nozzle	Spray	Nozzles utilized	Application	Droplet	Driving	Driving			Incidence (%)		Severity (%)		Sev. Index (%)				10% moisture						harvested grain		cleaned grain		kernels		23/64 sieve		22/64 sieve		20/64 sieve
	Placement	Pattern	(Spraying Systems TeeJet)	Pressure	Size	Speed	Direction			-  Sept 21-22   |   R9 growth stage  -						Sept. 15; R8		lbs/ac		lbs/bu		seeds/lb		% by weight		% by weight		%		% by weight
1	Non-treated control									83	a*	100	a*	83	a*	4.8	b*‡	891	b*	21.6	a*	3364	a*	10	a*	6	a*	1.2	a*‡	33	a*	51	a*	14	a*
2	Boom-mounted nozzles	flat fan	XR8001VS at 20-inch spacing	40 psi	Fine	2.0				59	a	100	a	59	a	0.1	a	1468	ab	22.8	a	3334	a	9	a	5	a	1.6	a	27	a	45	a	18	a
3	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	40 psi	Fine	2.6	East (90˚ from the north)			78	a	100	a	78	a	0.1	a	1638	a	22.7	a	3216	a	10	a	6	a	2.3	a	31	a	51	a	12	a
4	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	40 psi	Fine	2.6	West (270˚ from the north)			74	a	98	a	73	a	0.0	a	1052	ab	22.1	a	3604	a	10	a	5	a	1.6	a	40	a	56	a	12	a
5	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	60 psi	Very Fine	3.2	East (90˚ from the north)			72	a	100	a	72	a	0.4	ab	1612	a	22.0	a	3679	a	10	a	5	a	1.7	a	34	a	51	a	16	a
6	Undercover 360 drop nozzle	flat fan	XR11001VS on side ports	60 psi	Very Fine	3.2	West (270˚ from the north)			82	a	100	a	82	a	0.1	a	834	b	21.4	a	3400	a	13	a	6	a	3.4	a	36	a	57	a	12	a
7	Undercover 360 drop nozzle	hollow cone	TX-VK3 on side ports	60 psi	Very Fine	1.6	East (90˚ from the north)			64	a	100	a	64	a	0.2	a	1565	ab	22.7	a	3394	a	9	a	6	a	2.0	a	36	a	55	a	11	a
8	Undercover 360 drop nozzle	hollow cone	TX-VK3 on side ports	60 psi	Very Fine	1.6	West (270˚ from the north)			79	a	100	a	79	a	0.1	a	1260	ab	21.3	a	3255	a	12	a	7	a	1.5	a	42	a	62	a	8	a
							F:			1.83		1.00		1.86		4.00		3.57		1.69		0.98		1.59		0.76		0.46		0.44		0.58		1.03
							P>F:			0.1342		0.4586		0.1282		0.0063		0.0110		0.1652		0.4697		0.1927		0.6226		0.8507		0.8656		0.7663		0.4417
							CV:			17.1		1.5		17.1		172.3		26.2		4.2		9.5		24.8		32.5		67.0		40.3		25.7		42.9
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