Additional fertilizer and nematicide combinations on upland cotton to manage Rotylenchulus reniformis and Meloidogyne incognita in Alabama Author Gordon, Kara L Auburn University, 559 Devall Dr. CASIC Building, Auburn, AL 36849. Author Schrimsher, Drew W Auburn University, 559 Devall Dr. CASIC Building, Auburn, AL 36849. Author Lawrence, Kathy S Auburn University, 559 Devall Dr. CASIC Building, Auburn, AL 36849. lawrekk@auburn.edu text Journal of Nematology 2022 2021-08-19 54 1 1 15 http://dx.doi.org/10.21307/jofnem-2022-003 journal article 298699 10.21307/jofnem-2022-003 f78b7a11-93a0-4029-8993-53561cf3e1f9 2640-396X 11644663 Meloidogyne incognita field evaluation Plant stand was not affected by the additional fertilizer or Vydate ® C-LV combinations ( Table 6 ). The additional fertilizer and nematicide combinations did not significantly increase root fresh weight in samples taken at PHS + FB. Meloidogyne incognita eggs per gram of root were not significantly reduced in samples taken at PHS + FB. A nematicide ST + (NH 4 ) 2 SO 4 at PHS and FB had the lowest M. incognita eggs per gram of root, represented by the combined sample. The combination of a nematicide ST + 28-0- 0-5 + Vydate® C- LV + Max-In® at PHS and FB had a significantly higher lint yield when compared to application of (NH4)2SO4 at PHS or 28-0-0-5 at PHS ( P ≤ 0.10). Lint yield was increased by 433 kg /ha and 447 kg /ha or 35% and 38% with the combination of a nematicide ST + 28-0-0-5 + Vydate® C- LV + Max-In® at PHS and FB when compared to the lowest yielding treatments, (NH4)2SO4 at PHS and 28-0-0-5 at PHS. Table 5. Field trial LS meansz from 2019 and 2020 representing profit mean ($/ ha), and lower and upper profit determined by ANOVA (P ≤ 0.10) for fertilizer and nematicide combinations on DP 1646 B2XFy at the Tennessee Valley Research and Extension Center.

No	Treatments	Mean profit		Lower profit	Upper profit	Additional fertilizer and nematicide input costx
1	(NH) SO – PHSw 4 2 4	$862.69	bz	$677.97	$1047.41	$56.06
2	28-0-0-5 – PHS	$844.55	b	$659.83	$1029.27	$30.20
3	STv + (NH) SO – PHS 4 2 4	$880.33	ab	$695.61	$1065.05	$100.13
4	ST + 28-0-0-5 – PHS	$920.39	ab	$735.67	$1105.11	$77.27
5	ST + (NH) SO – PHS + FBu 4 2 4	$988.46	ab	$803.74	$1173.18	$153.19
6	ST + 28-0-0-5 – PHS + FB	$784.57	b	$599.84	$962.29	$107.47
7	ST + (NH) SO + Vydate® C-LV- PHS 4 2 4	$1175.87	a	$991.15	$1360.59	$138.73
8	ST + 28-0-0-5 + Vydate® C-LV- PHS	$913.44	ab	$728.72	$1098.16	$115.87
9	ST + (NH) SO + Vydate® C-LV + Max-In® 4 2 4 Sulfur – PHS	$974.36	ab	$789.64	$1159.08	$150.00
10	ST + 28-0-0-5 + Vydate® C-LV + Max-In® Sulfur – PHS	$902.49	ab	$717.77	$1087.21	$127.14
11	ST + (NH) SO + Vydate® C-LV + Max-In® 4 2 4 Sulfur – PHS + FB	$882.36	ab	$697.64	$1067.08	$252.93
12	ST + 28-0-0-5 + Vydate® C-LV + Max-In® Sulfur – PHS + FB	$922.73	ab	$738.01	$1107.45	$207.21

Notes: Revenue was calculated using prices determine by the United States Department of Agriculture upland cotton announcement of $1.32/ha in 2019 and $1.54/ha in 2020. Profit was calculated by subtracting additional input costs ($/ha) from revenue. zLS-means followed by the same letter are not significantly different at P ≤ 0.10 as determined by ANOVA . Lower and upper profits are the 90% confidence levels. yAll DP 1646 B2XF seeds were pretreated with a BASF fungicide and insecticide metalaxyl, pyraclostrobin, myclobutanil, imidacloprid, and fluxapyroxad. xAdditional input costs from 2019 and 2020 were averaged to determine a single input cost for treatment analysis. wPHS refers to the pinhead square plant growth stage, when the first combination of additional fertilizers and nematicides were applied. vST refers to nematicide seed treatment, Aeris® (Thiodicarb) applied in 2019 and COPeO™ Prime (Fluopyram) applied in 2020. uFB refers to the first bloom plant growth stage, when the second combination of fertilizers and nematicides were applied. Mean profits for fertilizer applications of (NH4)2SO4 and 28-0-0-5 at PHS with no nematicides averaged $548.53 ( Table 7 ). A nematicide ST with an additional fertilizer application at PHS increased mean profit by $54/ha from an additional fertilizer application alone. A nematicide ST with an additional application of fertilizer at PHS and FB increased profit by $103/ ha from an additional fertilizer application alone. Fertilizer combinations with Vydate® C-LV applied at PHS had an increased profit of $93/ha from an additional fertilizer application alone. Fertilizer and nematicide combinations that included Vydate® C-LV at PHS and FB had an increased profit of $131/ha. All combinations were compared to the mean profit of treatments of an additional fertilizer with no nematicides to determine increased profit per hectare. The combination of a nematicide ST + 28-0-0-5 + Vydate® C-LV + Max-In® Sulfur at PHS and FB had the greatest overall mean profit of $784.00 which was significantly greater than the mean profit of treatments of (NH4)2SO4 or 28-0-0-5 at PHS.