LACE BUG: A NEW EMERGING NOTORIOUS PEST OF COTTON
Faisal Hafeez, Asifa Hameed, Imran Nadeem, Dilbar Hussain, Muhammad Jawad Saleem, Qurban Ali, Naeem Arshad Maan and Arshed Makhdoom Sabir
Ayub Agricultural Research Institute, Faisalabad
Cotton lace bug (Corythucha gossypii Fabricius; Hemiptera: Tingidae) has recently gained attention as an emerging pest of cotton and reported from Multan, causing considerable concern for cotton growers. Cotton found as primary host, and exhibits a wide host range, infesting several malvaceous crops such as okra, brinjal, sesame, and sunflower. Both nymphs and adults feed on the undersides of leaves, where they pierce plant tissues and suck sap, leading to chlorosis, yellow stippling, and necrosis. Heavy infestations result in premature leaf senescence and defoliation, substantially reducing photosynthetic capacity, lint yield, and fiber quality. The population dynamics are strongly influenced by environmental factors such as hot and dry conditions favoring rapid multiplication, while rainfall and high humidity suppress populations by dislodging immatures. The pest’s rapid reproductive potential, overlapping generations, and expanding distribution highlight its increasing economic significance and the urgent need for comprehensive studies on its biology, ecology, and management to safeguard sustainable cotton production.
It undergoes incomplete metamorphosis, progressing through three distinct stages: egg, nymph, and adult. Females deposit 20–50 eggs either singly or in small clusters along the midrib or veins on the undersides of leaves. The eggs are initially whitish but gradually turn brown, with an incubation period of 4–6 days depending on ambient temperature. Upon hatching, the nymphs pass through five instars over a duration of 10–15 days. These nymphs are wingless, spiny, and typically gregarious, feeding in clusters that produce characteristic silvery patches on the leaf surface. Adults are delicate insects distinguished by their lace-like, reticulated wings, with a life span ranging from 15 to 25 days. The presence of multiple overlapping generations within a single season enables rapid population buildup under favorable hot and dry conditions, thereby intensifying their pest status. Unlike other major sucking pests of cotton such as whiteflies (Bemisia tabaci), which reproduce prolifically and are important virus vectors, or jassids (Amrasca biguttula biguttula), which inject phytotoxic saliva leading to “hopper burn,” the lace bug causes direct cellular damage by continuous sap extraction from the undersides of leaves. This distinct feeding strategy, coupled with its rapid life cycle, highlights the lace bug as an increasingly important pest requiring targeted ecological and management studies.
The feeding behavior of the cotton lace bug is characterized by continuous sap-sucking activity, predominantly from the lower leaf surface. Using piercing-sucking mouthparts, both nymphs and adults extract cell sap and inject toxic saliva, resulting in localized tissue collapse, chlorotic stippling, and progressive leaf necrosis. Nymphs typically feed in aggregates, a behavior that not only intensifies localized damage but also enhances their survival by reducing risks from desiccation and predation. Adults, though weak fliers, are capable of short-distance dispersal between host plants, and their spread across fields is often aided by wind currents.
Recommendations
Effective management of the cotton lace bug requires a holistic and integrated approach.
• Cultural practices such as timely sowing, maintaining recommended plant spacing, avoiding excessive nitrogen fertilization, and removal of heavily infested leaves should be prioritized as the first line of defense. Farmers should adopt regular monitoring and scouting programs to detect early infestations, particularly during periods of hot and dry weather when populations tend to peak.
• Biological control should be encouraged through the conservation of natural enemies including ladybird beetles, lacewings, spiders, and parasitoids, along with the use of entomopathogenic fungi such as Beauveria bassiana and Verticillium lecanii. The deployment of eco-friendly botanical formulations, such as neem-based products, can further suppress populations without disrupting natural enemy complexes.
• When pest incidence exceeds the economic threshold (1-2 bugs/ leaf), need-based chemical interventions may be employed using selective systemic or contact insecticides applied to target the undersides of leaves. However, indiscriminate use of broad-spectrum insecticides should be avoided to minimize resistance development and safeguard beneficial organisms. The adoption of resistant or tolerant cotton varieties, where available, can provide additional protection against infestations.
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