Sweet Potato Whitefly – Bemisia tabaci
Sweet potato Whitefly – Bemisiatabaci
Common Name: Sweet potato Whitefly
Latin Name: Bemisiatabaci
Female whiteflies lay pear-shaped eggs from the leaf’s bottom surface into the mesophyll or inner tissue. The eggs are linked to the leaf through a stalk-like mechanism and are white when originally laid before becoming brown before hatching. Females lay between 28 and 300 eggs, depending on the host and temperature. Egg density can reach 1,200 eggs per square inch.
The initial nymphal stage is called crawlers, and the last stage is the pupa. The crawlers wander a short distance after hatching before settling down to eat. Nymphs are creamy white to light green, with an oval form. The entire nymphal phase lasts around 2-4 weeks.
Sweet potato whiteflies are little, around 1/25 inch long, with a pale yellow body, two pairs of white wings, and a white waxy powder covering. Depending on the temperature, adults have a life expectancy of 6-55 days. Females survive just 10-15 days in the southern continental United States during the summer but can live for several months during the winter.
The sweet potato whitefly affects about 500 plant species from 63 plant families. It has been discovered on Hawaii’s crop plants: annona, avocado, broccoli, cauliflower, Chinese cabbage, cucumber, Dendrobium (flowers), and edible gourds. Cabbage, chrysanthemum, beans, bittermelon, dishrag squash, pepper, pea, and radish are some of the other crop hosts. Weeds are frequently used as alternate hosts for agricultural pests. Non-crop hosts include Asystasia, Coccinia sp., castor bean, Euphorbia, ilima, Ipomoea spp., and Malva sp.
Damages caused by Sweet potato Whitefly:
The sweet potato whitefly is a significant pest on a variety of crops. This bug may inflict three sorts of damage: direct, indirect, and viral. The piercing and sucking of sap from plant leaves cause direct injury. This feeding weakens the plant and promotes early withering, reducing the plant’s growth rate and production. It can also induce leaf chlorosis, wilting, premature leaf loss, and plant death. Infestations of sweet potato whitefly nymphs have been linked to irregular tomato ripening and squash silverleaf. Johnson et al. (1992) describe and repeat observations of the harm caused by sweet potato whitefly in Hawaii. Whitefly honeydew serves as a substrate for the formation of black sooty mould.
Life history and habits:
Whiteflies are linked to mealybugs and scale insects. Female adult whiteflies deposit eggs in a circular pattern because the female uses her feeding proboscis to pivot while laying eggs. When maintained at 16.7oC (62F) or 32.5oC (90.5), eggs require 5 to 22.5 days to emerge as crawlers on cotton. After hatching, a mobile stage known as “crawlers” seeks a suitable settling location. Once established, whitefly nymphs are thought to be quite stationary until transformation. In cotton, the overall development time from egg to adult ranges from 16.6 days at 30oC (86F) to 65.1 days at 14.9oC (59F). Adult females lay 72-81 eggs and live an average of 8 to 10.4 days.