Tolerance of the sunflower to herbicides

Source: INTA - Edition: Cálamo, contents for internet

The sunflower is a sensitive cultivation to most of the herbicides that are applied in preemergencia. He/she can also manifest sensibility to the postemergencia herbicides used for control of overgrowths of wide leaf, and in some cases presiembra herbicides.

The symptoms observed by the application of herbicides to the floor are fleeting, affecting in some cases the emergency of the sunflower, and in general they are presented in the first developed leaves and in certain situations-high quantity and intensity of later rains to the application-irreversible damages can take place in the plants (as their death), due to a bigger absorption of herbicides applied to the floor that takes place mainly through the hipocotile of the sunflower, although it can also enter for the cotyledons and radícula.

It should be kept in mind, to reduce the possibilities to damage to the cultivation that the applications of herbicides preemergentes should be carried out the more fence possible of the siembra moment, avoiding their realization in the state of "cracking" or emergency.

Presiembra herbicides

Dinitramina, Pedimetalín and Trifluralina: in general they don't cause symptoms in the sunflower.

Butilato: it can cause difficulty in the emergency of the plántulas and deformations in the first leaves and detention of the growth.

Preemergencia herbicides

Acetoclor: It causes malformations in cotyledons, first couple of developed leaves, and possibly in the second couple. Dark green coloration. Flurocloridona: it causes amarillamiento of cotyledons, necrosis to foliate, decrease of height, and malformations.

Diflufenican: you stain yellow or white in the first couple of leaves, and amarillamiento.

Prometrina: chlorosis and necrosis of cotyledons and first couple of leaves and in some cases, plántula death.

Postemergencia herbicides

Aclonifen: you stain yellowish in the leaves.

Benazolín: deformations in the superior leaves, expansion of the nervaduras, clororsis.

Graminicidas: they don't cause symptoms unless they are applied in excess, case in which you/they cause fitotoxicidad.