(i) What are Lichens? Write their economic importance. (ii) Explain how insects are useful to human beings.
In short
Lichens are composite organisms formed by a fungus and an alga or cyanobacterium, valued for dyes, perfumes, medicines, soil formation and as air-pollution bioindicators. Insects benefit humans by pollinating crops, controlling pests through predators like ladybird beetles, yielding honey, silk and lac, and recycling nutrients.
Model answer
Ghissu Editorial · Verified 4 Oct 2026 · 256 words
Symbiotic Nature
Lichens, a fungus-alga mutualism, colonize harsh habitats, aiding soil formation and nutrient cycling in Eastern Ghats of Andhra Pradesh, which supports forest health and agricultural productivity.
Economic and Environmental Role
Harvested for dyes, perfumes, and traditional medicines, lichens provide income to local communities. They also serve as sensitive bioindicators in Andhra Pradesh's industrial corridors, helping monitor air pollution and guide sustainable development policies.
Pollination and Pest Control
Bees, butterflies, and parasitic wasps boost crop yields and control pests in Rayalaseema and Coastal Andhra, reducing chemical pesticide use and enhancing food security.
Economic Products and Soil Health
Sericulture in Anantapur district supports rural employment and export revenue; detritivorous insects enhance soil fertility and moisture retention in drought-prone Rayalaseema, sustaining agrarian livelihoods.
Threats and Awareness
Pollution and habitat loss threaten lichens and beneficial insects; extension services from institutions like Acharya N.G. Ranga Agricultural University are essential to raise farmer awareness and adoption of biological methods.
Conservation and Research
Community-based conservation programs in forest fringes and focused R&D on lichen biofertilizers and insect pest management tailored to Andhra Pradesh's agro-climatic conditions can sustain these vital resources.
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