Skip to main content
ARS Home » Southeast Area » Tifton, Georgia » Crop Protection and Management Research » Research » Publications at this Location » Publication #307984
Title: The effect of 2,4-dichlorophenoxy acid (2,4-D) on peanut when applied during vegetative growth stages

Author
item BLANCHETT, B - University Of Georgia
item GREY, T - University Of Georgia
item PROSTKO, E - University Of Georgia
item VENCILL, W - University Of Georgia
item Webster, Theodore

Submitted to: Peanut Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/29/2015
Publication Date: 7/6/2017
Citation: Blanchett, B.H., Grey, T.L., Prostko, E.P., Vencill, W.K., Webster, T.M. 2017. The effect of 2,4-dichlorophenoxy acid (2,4-D) on peanut when applied during vegetative growth stages. Peanut Science. 44:53-59.

Interpretive Summary: The development of 2,4-D-resistant cotton and soybean cultivars has created great concern about the potential off-target movement of 2,4-D onto sensitive broadleaf crops. Peanut is often grown in close proximity to cotton and soybean. Field studies were conducted to evaluate peanut response to 2,4-D at five rates and four peanut growth stages. Results indicated that peanut injury increased with rate of 2,4-D. There was variation in yield loss response dependent on peanut growth stage at application timing. Peanut injury, canopy diameter, and peanut yield loss varied due to 2,4-D treatments made at different peanut growth stages. When 2,4-D was applied preemergence and at the peanut V2 growth stage, peanuts were injured, but peanut recovered and had no yield loss. There were significant increases in peanut injury as 2,4-D rate increased, especially after V3 and V5 treatments. Peanut treated at V3 and V5 growth stages had injury up to 32% and peanut yield loss up to 36%; in part due to reproductive growth being initiated during that time and peanut had less time to recuperate before harvest. Visual estimates of injury and canopy diameter measurements of peanut in the present study provided practical and easily obtained information that a grower could obtain with minimal cost. Visual estimates of peanut injury at 20 DAT were correlated with peanut yield when 2,4-D was applied at V3 to V5 growth stages. Due to the sensitivity of peanut to 2,4-D, growers and applicators should avoid applying 2,4-D in the proximity of peanut during V3 to V5 growth stages and early reproductive growth stages. In the unfortunate situation where peanut injury from accidental 2,4-D exposure occurs, these data could assist the grower in determining peanut yield loss estimates and a possible plan of action.

Technical Abstract: The development of 2,4-D-resistant cotton and soybean cultivars has created great concern about the potential off-target movement of 2,4-D onto sensitive broadleaf crops. Peanut is often grown in close proximity to cotton and soybean. Therefore, field studies were conducted during 2012 and 2013 at Plains, Ty Ty, and Attapulgus, GA to evaluate peanut response to 2,4-D at 67, 133, 266, 533, and 1066 g ae ha-1 applied at preemergence (PRE), 10, 20, or 30 d after planting (DAP), corresponding to PRE, V2, V3, and V5 peanut growth stages. Nontreated controls were included for comparison. Treatment timing by rate (P < 0.0001) interactions were significant. As 2,4-D rate increased peanut injury increased. There was variation in yield loss response dependent on peanut growth stage at application timing. Peanut that was treated preemergence and at the V2 growth stage did not have yield loss at any rate of 2,4-D evaluated (67 to 1066 g ha-1) relative to the nontreated control. When peanut was treated at V3 and V5 growth stages with 2,4-D, injury estimates were 5 to 32% from the 67 to 1066 g ha-1 rates respectively, and peanut canopy diameter was stunted 5 to 35% at the same rates. The resulting peanut yield loss was 23 and 36% from 533 and 1066 g ha-1 of dicamba applied at V3 and V5 growth stages; in part due to reproductive growth being initiated during that time-frame and peanut had less time to recuperate before harvest. Linear regression models were used to evaluate peanut injury and peanut yield results. Significant correlations were established for V3 and V5 treatments between injury and yield, injury and canopy diameter, and canopy diameter and yield (P < 0.0001), with correlation coefficients of – 0.48, – 0.76, and 0.51, respectively. Growers and extension agents will be able to use these peanut injury estimates and canopy diameter data to make improved predictions of potential peanut yield loss where off-target movement of 2,4-D or sprayer contamination has occurred.