Rotylenchulus reniformis

Gordon, Kara L, Schrimsher, Drew W & Lawrence, Kathy S, 2022, Additional fertilizer and nematicide combinations on upland cotton to manage Rotylenchulus reniformis and Meloidogyne incognita in Alabama, Journal of Nematology 54 (1), pp. 1-15 : 10-11

Rotylenchulus reniformis microplot evaluation

A nematicide ST + 28-0-0-5 + Vydate® C-LV + Max-In® Sulfur at PHS was the most effective combination in reducing R. reniformis eggs per gram of root sampled at PHS + FB. The combination of a nematicide ST + (NH4)2SO4 + Vydate® C-LV + Max-In® Sulfur at PHS and FB was the most effective treatment in increasing seed cotton yield. The combination of a nematicide ST + (NH4)2SO4 + Vydate® C-LV + Max-In® Sulfur at

and lower and upper profit determined by ANOVA (P ≤ 0.10) for fertilizer and nematicide combinations on DP 1646 B2XFy at the Plant Breeding Unit.

No Treatments

Additional fertilizer Mean Lower Upper

and nematicide profit profit profit

input costx

1 (NH4)2SO4 – PHSw $553.01 bz $461.43 $644.59 $56.06 2 28-0-0-5 – PHS $544.05 b $452.47 $635.63 $30.20

3 STv + (NH4)2SO4 – PHS $569.21 ab $477.63 $660.79 $100.13 4 ST + 28-0-0-5 – PHS $635.85 ab $544.27 $727.43 $77.27

5 ST + (NH4)2SO4 – PHS + FBu $608.01 ab $516.43 $699.59 $153.19 6 ST + 28-0-0-5 – PHS + FB $695.76 ab $604.18 $787.34 $107.47

7 ST + (NH4)2SO4 + Vydate® C-LV – PHS $627.25 ab $535.67 $718.83 $138.73 8 ST + 28-0-0-5 + Vydate® C-LV – PHS $683.50 ab $591.92 $775.08 $115.87

9 ST + (NH4)2SO4 + Vydate® C-LV + Max-In® $616.22 ab $524.64 $707.80 $150.00

Sulfur – PHS

10 ST + 28-0-0-5 + Vydate® C-LV + Max-In® $640.59 ab $549.01 $732.17 $127.14

Sulfur – PHS

11 ST + (NH4)2SO4 + Vydate® C-LV + Max- In® $575.53 ab $483.95 $667.11 $252.93

Sulfur – PHS + FB

12 ST + 28-0-0-5 + Vydate® C-LV + Max-In® $784.00 a $692.42 $875.58 $207.21

Sulfur – PHS + FB

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 additional combination

of 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 additional fertilizers and nematicides were applied.

PHS and FB increased seed cotton yields by 50% when compared to the combination of a nematicide ST + (NH4)2SO4 at PHS. Research supports the use of Vydate® C- LV on cotton during PHS and sequential treatments reducing R. reniformis population levels ( Hammes et al., 1999). Applications of nematicides when analyzed individually increased lint yields by 8% with a nematicide ST, 19% with a single Vydate® C-LV application and 29% with a double application of Vydate®C-LV.