**2.9** *Spodoptera littoralis* **(Boisduval) (Lepidoptera: Noctuidae)**

**Identification:** The cotton leaf worm adult has a wingspan of 35 to 40 mm. Forewings are brownish with bluish overtones and straw yellow along the median vein. The ocellus is marked by 2 or 3 oblique whitish stripes. The front of the wing tip has a blackish marking, more pronounced in the male. Hind wings are whitish, with a brown front edge. Eggs are spherical and about 0.6 mm long. Neonate larva is pale green with a brownish head; when fully developed (forth instar), it is 35 to 45 mm long. The color of larvae varies from grey to reddish or yellowish, with a median dorsal line bordered on either side by two yellowishred or grayish stripes, and small yellow dots on each segment. Pupa is about 15 to 20 mm long, brick red color (Vaamonde, 2006).

**Life cycle and damage:** adults appear in early spring and female lays eggs in clusters and covered with brownish-yellow hairs detached from the abdomen of the female. Most of the clusters are sited on the lower parts of plants. Eggs hatch after 3-4 days and after 2 weeks, pupation takes place in the soil at a depth of 2 to 5 cm. They overwinter as a pupa in the soil. When they are small they feed from the cuticle of the leaves, but if growing they feed from any green part of the plant and also from fruits, resulting in major defoliations. They can also chew the stems, where galleries are drilled. The injuries caused for that pest facilitate the penetration of other pathogens such as fungi, bacteria and etc (Vaamonde, 2006).

**Monitoring:** detect the presence of adults with monitoring device consisting on insecticide or pheromones traps (3-4 traps per acre). Once the first captures occurs, it is advisable to make a visual estimate by means of a direct sampling on the plants, paying attention to the leaves or other parts of the plant. Count the number of active larvae at the upper and lower surfaces of the leaves and determine the percentage of defoliation (Vaamonde, 2006).

**Economic and action thresholds**: observation of 35, 45 and 100 egg masses or 0.3, 0.4 and 0.9 larvae per plant is recommended as economic threshold during *S. littoralis* first, second, and third generations, respectively (El-Sherif et al., 1991).

**Control:** applying azadirachtin and neem oil can control and disrupt growth of insects. Also, sex pheromones can use in the control programs (Martinez & Emden, 2001). Pineda et al., (2007) stated that combination of lethal and sub lethal doses of methoxyfenozide and spinosad might significantly control the population dynamics of *S*. *littolaris*.

**Control:** damsel bugs, big-eyed bugs, predatory shield bugs, as well as lynx, night stalker and jumping spiders are known to feed on mirid adults, nymphs and eggs (Yvette & Jensen, 2009). *C. dilutus* is coincidentally controlled in cotton by applications of insecticides targeted

Occasionally green peach aphid, *Myzus persicae* (Sulzer) and cowpea aphid, *Aphis craccivora* (Koch) (Hompotera: Aphididae), infest young cotton. Green vegetable bug, *Nezara viridula* (L.) (Hemiptera: Pentatomidae), pale cotton stainer, *Dysdercus sidae* (Montr.) and red cotton bug, *Dysdercus cingulatus* (F.) (Hemiptera: Pyrrhocoridae) sometimes cause economic damage and heavy crop losses in some regions. Also, brown mirid, *Creontiades pacificus* (Stål) (Hemiptera: Miridae) and cottonseed bug, *Oxycarenus luctuosus* (Montrouzier) (Hemiptera: Lygaeidae) can cause damage to the cotton but the damage of these pests is

**Identification:** The cotton leaf worm adult has a wingspan of 35 to 40 mm. Forewings are brownish with bluish overtones and straw yellow along the median vein. The ocellus is marked by 2 or 3 oblique whitish stripes. The front of the wing tip has a blackish marking, more pronounced in the male. Hind wings are whitish, with a brown front edge. Eggs are spherical and about 0.6 mm long. Neonate larva is pale green with a brownish head; when fully developed (forth instar), it is 35 to 45 mm long. The color of larvae varies from grey to reddish or yellowish, with a median dorsal line bordered on either side by two yellowishred or grayish stripes, and small yellow dots on each segment. Pupa is about 15 to 20 mm

**Life cycle and damage:** adults appear in early spring and female lays eggs in clusters and covered with brownish-yellow hairs detached from the abdomen of the female. Most of the clusters are sited on the lower parts of plants. Eggs hatch after 3-4 days and after 2 weeks, pupation takes place in the soil at a depth of 2 to 5 cm. They overwinter as a pupa in the soil. When they are small they feed from the cuticle of the leaves, but if growing they feed from any green part of the plant and also from fruits, resulting in major defoliations. They can also chew the stems, where galleries are drilled. The injuries caused for that pest facilitate

**Monitoring:** detect the presence of adults with monitoring device consisting on insecticide or pheromones traps (3-4 traps per acre). Once the first captures occurs, it is advisable to make a visual estimate by means of a direct sampling on the plants, paying attention to the leaves or other parts of the plant. Count the number of active larvae at the upper and lower

**Economic and action thresholds**: observation of 35, 45 and 100 egg masses or 0.3, 0.4 and 0.9 larvae per plant is recommended as economic threshold during *S. littoralis* first, second, and

**Control:** applying azadirachtin and neem oil can control and disrupt growth of insects. Also, sex pheromones can use in the control programs (Martinez & Emden, 2001). Pineda et al., (2007) stated that combination of lethal and sub lethal doses of methoxyfenozide and

the penetration of other pathogens such as fungi, bacteria and etc (Vaamonde, 2006).

surfaces of the leaves and determine the percentage of defoliation (Vaamonde, 2006).

spinosad might significantly control the population dynamics of *S*. *littolaris*.

at other pests such as *Heliothis* spp. (McColl et al., 2011).

minor and doesn't require control.

long, brick red color (Vaamonde, 2006).

third generations, respectively (El-Sherif et al., 1991).

Some other important sucking insect pests of cottonseeds are:

**2.9** *Spodoptera littoralis* **(Boisduval) (Lepidoptera: Noctuidae)** 
