Cumin: Insect and Nematode Pests Management

Aphid

During the summer months, the aphid continues to produce wingless off spring by a process called parthenogenesis; the production of off spring without the involvement of sex. From time to time, winged off spring are produced and these fly away to colonise new plants. In the Autumn the winged individuals include males.

The males fly off to a woody shrub or tree and are joined by winged females. Here the females produce wingless off spring which are mated by the males and then lay hard-shelled eggs on the tree branches. In this form the aphids survive the winter. In Spring the eggs hatch to wingless females which produce winged off spring by parthenogenesis. The winged off spring fly to the plants on which they will feed and establish new colonies.

• Direct damage: Aphids damage plants by puncturing them and sucking their juices. They damage the young and soft parts of plants, such as new leaves and shoots. Signs of damage are leaves not opening properly and being smaller in size. Severe infestation can cause shoots to wilt and dry out.
• Indirect damage: Aphids have wings and can move from plant to plant spreading viral diseases, picked up from infected plants. Aphids secrete a sugary liquid that stimulates black sooty mold growth. It can cover the surface of leaves which affects the way they absorb sunlight.

• Parasitoids: Lysiphlebus sp, Diaeretiella sp, Aphelinus sp, Aphidius colemani
• Predators: Ladybird beetle, lacewing, spiders, hover fly etc.

Thrips

• Egg: Eggs are white to yellow, kidney-bean shaped, microscopic in size. Develop within leaf tissue with one end near the leaf surface. Egg stage is 5-10 days.
• Larva: Instars I and II are active, feeding stages. White to pale yellow in colour, elongate and slender body, Nymphs resemble adult, but without wings. Antennae are short and eyes are dark in color. Crawl quickly when disturbed. Larval stage is 10-14 days.
• Pre-pupa and pupa: Instars III and IV are inactive, non-feeding stages called pre-pupa and pupa, respectively. Pale yellow to brown in colour; body more stout than younger instars. Antennae are bent to head; wing buds are visible. Found in the soil. Pre-pupal and pupal stages last 5-10 days.
• Adult: About 1.5 mm long; elongate, yellow and brown body with two pairs of fringed (hairy) wings. Mouthparts are beak-like and antennae are 7-segmented. Parthenogenic (asexually reproducing) females; males are extremely rare. Females insert eggs individually into leaves. Adult life span is about 1 month and females lay eggs for about 3 weeks.

• Direct damage: Thrips damage the undersides of leaves by sucking their juices. They damage young and soft parts of plants such as new leaves and shoots.
• As a result, leaves curl downwards and change to a blackish- silver color. Severe infestation causes young leaves to wilt and dry out.
• Indirect damage: Thrips can carry and spread viral diseases.

• Parasitiod: Ceranisus menes
• Predators: Predatory thrips, minute pirate bug, ladybird beetle, lacewing, mirid bug, hover fly etc.

Cutworm

• Egg: Each female moth come out at dusk and lay creamy white, dome-shaped eggs (200-350) in clusters of about 30 each, either on the under surface of the leaves of host plants or in the soil.
• Larva: Newly emerged young larva is yellow in colour, 1.5 mm long with a shiny, black head and a black shield on the prothorax. The full-grown larva is about 42-45 mm long and is dark or dark brown with a plump and greasy body. Larvae live in the soil and are yellow or blackish- green in color. They have striped markings running down the sides of their bodies. The larval stage varies from 30-34 days
• Pupa: Pupae are brown to dark brown, about 1.5 to 2.0 cm in length and are usually found in or on piles of leaf mould. Pupation takes place underground in an earthen chamber. Pupal period is completed in 10 to 30 days
• Adult: Adult measures about 25 mm from the head to the tip of the abdomen and looks dark with some grayish patches on the back and dark streaks on the forewings. Adults live for 7-10 days. Total life cycle takes up to 36 days (from egg to adult). The moths usually emerge at night. This pest generally completes three generations in a year.

• Both adult and caterpillars become active at night.
• During the day time caterpillars hide in crack and crevices in the soil.
• They attack young plants by severing their stems, pulling all parts of the plant into the ground and devouring them.
• Plants with severed stems have difficulty growing again.
• This pest can cause serious damage; particularly when crops are at 25 - 35 days after planting.

• Persistent dry weather with lesser or no rainfall, reduced humidity & 16° C-23° C temperatures favor the development of cutworm.

• Parasitoids: Trichogramma spp., Tetrastichus sp, Telenomus sp, Bracon sp, Campoletis sp Chelonus sp, Ichneumon sp, Carcelia sp etc.
• Predators: Lacewing, ladybird beetle, spider, red ant, dragonfly, robber fly, reduviid bug, praying mantis, King crow etc.

Cigarette beetle

• Egg: An egg is pearly white, and is not easily seen with the naked eye. When fully grown, beetle larvae is C-shaped (grub-like) and about 3/16-inch long. Female lays about 30 eggs in a period of 3 weeks. Eggs hatch in 6 to 10 days.
• Larva: Larvae are creamy white and covered with long, yellowish-brown hairs. They have a brown head and legs. The larval stage lasts from 5 to 10 weeks.
• Pre-pupa and pupa: The pre-pupal and pupal periods last 2 to 3 weeks and are passed in a cell.
• Adult: Adults are yellowish- to reddish-brown, oval-shaped, and about 1/10-inch long. The head is bent downward sharply, nearly at right angles to the body, giving a humpbacked appearance when viewed from the side. The wing covers (elytra) are smooth, and the antennal segments are uniform and saw-like (serrate). Adults are strong flyers and active in subdued light at temperatures above 65° F. Adult beetles may live from 23 to 28 days. In temperate climates, beetles begin swarming in May and again in August. Overwintering may be passed in the larval stage, with some adults not too resistant to cold hibernating in crevices. There may be 5 to 6 overlapping generations per year in warm localities with only one generation in the more temperate regions. In warehouses, the life cycle may be completed in 52 days.

Drugstore beetle

• Egg: Females lay up to 75 eggs in the food or substrate.
• Larva: The larval period ranges from 4 to 20 weeks. Larvae tunnel through the substrate and when fully grown build a cocoon and pupate.
• Pupa: Pupal period is 12 to 18 days.
• Adult: The beetles are cylindrical, 2.25 to 3.5 mm long, and are uniform brown to reddish brown in colour. Have longitudinal rows of fi ne hairs on the elytra (wing covers). The antennae of the cigarette beetle are serrated (like the teeth on a saw) while the antennae of the drugstore beetle are not and end in a 3-segmented club. The elytra (wing covers) of the drugstore beetle have rows of pits giving them striated (lined) appearance. Adult females live approximately 13 to 65 days. The entire life cycle is generally less than two months but can be as long as 7 months.

• The duration of the life cycle is highly dependent on the temperature and food source. Development occurs between 60 to 93° F (15 to 34° C) but is optimal at about 85° F (30° C) and 60 to 90% relative humidity.

Tobacco caterpillar

It is found throughout the tropical and sub-tropical parts of the world, wide spread in India. Besides tobacco, it feeds on cotton, castor, groundnut, tomato, cabbage, cumin and various other cruciferous crops.

• Egg: Female lays about 300 eggs in clusters. The eggs are covered over by brown hairs and they hatch in about 3-5 days.
• Larva: Caterpillar measures 35-40 mm in length, when full grown. It is velvety, black with yellowish – green dorsal stripes and lateral white bands with incomplete ring – like dark band on anterior and posterior end of the body. It passes through 6 instars. Larval stage lasts 15-30 days
• Pupa: Pupation takes place inside the soil. Pupal stage lasts 7-15 days.
• Adult: Moth is medium sized and stout bodied with forewings pale grey to dark brown in colour having wavy white crisscross markings. Hind wings are whitish with brown patches along the margin of wing. Pest breeds throughout the year. Moths are active at night. Adults live for 7-10 days. Total life cycle takes 32-60 days. There are eight generations in a year.

• In early stages, the caterpillars are gregarious and scrape the chlorophyll content of leaf lamina giving it a papery white appearance. Later they become voracious feeders making irregular holes on the leaves.
• Irregular holes on leaves initially and later skeletonization leaving only veins and petioles
• Heavy defoliation.

• Maximum S. litura built up at temperature ranges from 26.0° C to 35.1° C, relative humidity ranges from 89 and 62%, zero rainfall, total sunshine hours (64.6 hrs/week),
• S. litura population showes a positive correlation with relative humidity, sunshine hours, whereas negatively correlated with wind velocity

• Parasitoids: Trichogramma sp, Tetrastichus sp, Telenomus sp, Bracon sp, Campoletis sp, Chelonus sp, Ichneumon sp, Carcelia sp etc.
• Predators: Lacewing, ladybird beetle, spider, red ant, dragonfly, robber fly, reduviid bug, praying mantis, King crow etc.

Root-knot nematode

• Most species of plant parasitic nematodes have a relatively simple life cycle consisting of the egg, four larval stages and the adult male and female.
• Development of the first stage larvae occurs within the egg where the first molt occurs. Second stage larvae hatch from eggs to find and infect plant roots or in some cases foliar tissues.
• Under suitable environmental conditions, the eggs hatch and new larvae emerge to complete the life cycle within 4 weeks at 30 ° C and 8 weeks at 20 ° C.

• Nematode development is generally most rapid within an optimal soil temperature range of 21 - 26° C.

IPM for Cumin

To know the IPM practices for Cumin, click here.

Source: NIPHM and Directorate of Plant Protection, Quarantine & Storage