*2.3.1. Methods of control*

caterpillars measure approximately 22–25 mm long, with brown head and whitish/yellowish

Regarding the cycle, oviposition is made in maize leaf after mating, generally on the dorsal side. The number of eggs in each oviposition is from 5 to 50, with an imbricated posture, resembling snake leather or fish scale. Immediately after hatching, and upon reaching the second instar, they enter the stem. Its attack can be identified by the inlet and outlet holes, as well as the longitudinal opening of the maize stalk, where the presence of the caterpillar or the

In high infestations, the attack of this insect can cause losses up to 21% in production. It can attack 65 plant species such as sugarcane, maize, millet, sweet sorghum, wheat, grain sorghum, and rice, besides many other grasses (Poaceae) and spontaneous weeds such as *Sorghum halepense*, *Paspalum* sp., *Panicum* spp., and *Holcu* ssp. Moreover, *Andropogon* ssp. The larvae damage maize in various ways: in small plants, by attacking the whorl, causing holes in the leaf blade to the death of the meristem. In more developed plants, they open galleries, feeding on the stem. These galleries are usually longitudinal but may present circular aspect, making the plant very susceptible to falling. Damages can also occur in the ear, allowing the cross

Depending on the behavior of this pest, chemical control usually does not present satisfactory result, unless the attack begins very early. In this case, seed treatment with systemic insecticides

In the past 60 years, the biological control of this pest in sugarcane crop has been successful with the caterpillar parasitoid *Cotesia flavipes* and, more recently, with the egg parasitoid *Trichogramma galloi* and may be extended to the control methodology for the maize crop.

Elimination of crop residues and host plants, especially grasses (Poaceae), help reduce the

Black cutworm, from the genus *Agrotis*, constitute an important group of insect pests, mainly due to damages to the large number of cultivated plants and their wide geographic distribu‐ tion. *Agrotis ipsilon* is the main species of black cutworm referred to in Brazil and is a poly‐ phagous insect, which attacks mainly horticultural crops [7]. It can also attack other species of

different plant families, in crops such as maize, soybeans, beans, and cotton [8].

or pyrethroid sprays directed toward the base of the plant gives good results.

body with numerous dark spots.

62 Insecticides Resistance

passageway left by it is observed.

infestation with weevils *Sitophilus* spp.

*2.2.1. Methods of control*

*2.2.1.1. Chemical control*

*2.2.1.2. Biological control:*

*2.2.1.3. Mechanical control*

infestation for the next crop season.

**2.3. Black cutworm (***Agrotis ipsilon***)**

To have an effective system of control for this pest, we recommend the use of various tactics of control, individually or harmoniously, creating a management strategy based on cost– benefit analyzes and with a reduction on the impact on the farmers, the society, and the environment adopting IPM.

## *2.3.1.1. Cultural control*

Early desiccation is a practice that can reduce the infestation of *Agrotis* spp. since the moths prefer to lay eggs on plants or crop residues still green. The highest incidence of attack occurs in areas of not cleaned and heavy soil. In this way, the correct postcultivation management is indispensable to keep the pest below the economic injury level [9].

#### *2.3.1.2. Insecticide application technology*

Due to the nocturnal habit of this pest, another management tactic that is important is the quality of pesticide application technology. This must be done directing the jet spray to the base of the plant, preferably in the early evening and with a high solution volume [8].
