PESTS OF TOBACCO


North Carolina Cooperative Extension
Extracted from INSECT and related PESTS of FIELD CROPS (AG-271)
Dated 5/82
Placed on the Web 11/96 by the Center for Integrated Pest Management, NCSU

With approximately 154,656 hectares (382,000 acres) devoted to tobacco in 1980, North Carolina produces well over 40 percent of all tobacco in the nation. The Coastal Plain and northern Piedmont counties lead other states in the production of flue-cured tobacco, while burley, an air-cured tobacco, is an important crop on small farms in the Mountain counties. Although many insect pests attack tobacco from the time it is seeded until it is marketed, their importance varies from area to area from year to year. The following key has been subdivided based on the growing schedule for flue-cured tobacco.

Key to Tobacco Pests

A. Soil insects which attack plant bed tobacco by uprooting plants, boring into stems or stalks, or feeding on roots (Fig. A to B).

  1. Green June beetle larva - This large white, six-legged grub has a blackish-brown head and is about 5 cm long when fully developed (Fig. A). It crawls on its back on the soil surface or burrows in the soil and uproots seedlings

  2. Southern mole cricket - About 32 mm long, the adult is brown with short front wings (the long membranous hind wings are usually tucked under the front wings) and shovel-like front legs for digging (Fig. B). The nymph is similar but smaller and wingless; both life stages uproot seedlings by tunneling and feeding on the roots.

B. Insects which attack plant bed and field tobacco.

  1. Insects which bore into stems or stalks or feed on roots.

    1. Tobacco flea beetle larva - This white, 12-segmented larva, 4.3 to 4.8 mm long when fully developed, has a brownish head, three pairs of legs near the head, and a proleg on the last abdominal segment. It may kill newly set plants by feeding on roots or tunneling in the stalk.

  2. Insects damaging leaves by sucking sap.

    1. Green peach aphid - This aphid is a soft-bodied, pear-shaped, winged or wingless insect about 2.0 mm long with a pair of long cornicles (tailpipe-like appendages) at the end of the abdomen. The adult has a pale yellow, green, or yellowish-green abdomen with a dark, dorsal blotch; the nymph resembles the adult but is light green and never winged. Both life stages damage plants by sucking sap from leaves, causing curled, stunted, distorted leaves, contaminated with honeydew and sooty mold fungi.

  3. Chewing insects damaging leaves or stems.

    1. Beetles - These insects have hard, shell-like forewings (wing covers or elytra) which meet in a straight line down the middle of the back (Fig. A to C). They may or may not be able to fly.

      1. Tobacco flea beetle - This very small (about 1.5 mm long), oval, black, jumping beetle (Fig. A) chews small round holes in leaves giving them a "shothole" appearance.

      2. Vegetable weevil - About 6.4 mm long, this brown, snout beetle (Fig. B) has a light, V-shaped mark on its wing covers. It attacks seedlings and newly set plants feeding on both leaves and buds, leaving irregular holes.

      3. Whitefringed beetles - Several species of these black, 11 mm-long beetles leave sawtooth cuts on the outer edges of tobacco leaves. Covered with grayish scales, each of these snout beetles has two longitudinal stripes down its back and a marginal band of long, white hairs (Fig. C). These beetles cannot fly.

    2. Cutworms - Cutworm caterpillars have three pairs of legs near their heads and five pairs of prolegs (Fig. A). Several species of these thick-bodied, grayish to dark brown larvae, up to 50 mm in length, hide curled up in the soil by day and feed at night on seedlings or newly set plants in the field. They sever the stems of young plants, cut off leaves, or chew large holes in the leaves.

    3. Vegetable weevil larva - Soft-bodied, legless, and pale green, this larva is about 10 mm long when mature (Fig. B). Like its adult form, this larva feeds on both leaves and buds, leaving irregular holes.

C. Insects which primarily attack field tobacco.

  1. Insects that feed on roots, bore into stems, or sever stems.

    1. Cutworms - See section B.3.b. of this key for description.

    2. Whitefringed beetle larvae - These yellowish-white, legless, 12-segmented grubs, up to 13 mm in length, have small, round, pale heads (Fig. A). They feed on roots, stunting or killing tobacco plants.

    3. Wireworms - These hard, elongated, yellowish-brown larvae (up to 19 mm long when fully developed) tunnel in the stalks of newly set plants, stunting or killing the plants. The tobacco wireworm's last segment terminates in a V-shaped notch, while the southern potato wireworm has an almost closed, oval notch (Fig. B).

  2. Insects damaging foliage by sucking sap.

    1. Suckfly - The adult is a green-black, slender plant bug, about 3.3 mm long, with long slender legs and antennae; the fully developed nymph is green with reddish eyes and two pairs of wing pads. Both life stages suck plant sap from late-season tobacco, reducing the coloration, weight, and thickness of cured leaves. Excrement is present on the underside of leaves.


    2. Green peach aphid - See section B.2.a. of this key.

  3. Insects damaging leaves by chewing holes.

    1. Caterpillars - These soft-bodied moth larvae have three pairs of legs near their heads and three to five pairs of prolegs (Fig. A to C).

      1. Budworms - Up to 44 mm in length when mature, these moderately hairy caterpillars vary in color from greenish-yellow or reddish-brown to near black with pale, longitudinal stripes and scattered black spots; young larvae are cream colored or yellowish-green with few markings. They have five pairs of prolegs (Fig. A). Damage from feeding in the bud area becomes apparent as the leaf expands.

      2. Cabbage looper - This light green larva, about 40 mm long when fully developed, tapers in width from the rear to the head. It has three pairs of thoracic legs near the head and three pairs of prolegs toward the rear (Fig. B). As it crawls, the looper arches the middle of its body. It chews ragged holes in leaves, leaving only the larger leaf veins.

      3. Hornworms - These large, green caterpillars (Fig. C) have either seven diagonal stripes on each side and a curved, red, posterior horn (tobacco hornworm) or eight V-shaped markings on each side and a straight, black horn (tomato hornworm). They are 75 to 85 mm in length when fully developed.

      4. Potato tuberworm - This greenish-to-pink caterpillar, 13 to 19 mm in length when fully developed, has five pairs of prolegs (Fig. A). It tunnels between leaf surfaces causing papery, grayish blotches which become brownish and brittle.

      5. Variegated cutworm - This smooth-bodied, dark brown, mottled larva has a distinct, pale yellow dot down the back of at least the first four abdominal segments and has five pairs of prolegs (Fig. A). It is about 50 mm long when fully developed, and unlike the black cutworm, it may climb tobacco plants and feed on leaves.

    2. Japanese beetle - This shiny, metallic-green beetle, about 1.3 cm long, has copper-brown wing covers and six tufts of white hairs on each side of the abdomen. It chews numerous ragged holes in leaves and usually feeds gregariously.