Explanation

• Barnyard grass (Echinochloa spp.) is a common weed in rice fields.
• It competes with rice plants for nutrients, water, and sunlight.
• Reduces yield and affects crop quality.
• Common in flooded and irrigated rice paddies.
• Effective weed management is crucial for rice cultivation.

Last verified on 12-02-2026

Explanation

• C4 plants (e.g., maize, sugarcane) perform C4 photosynthesis to minimize photorespiration.
• The first enzyme to fix CO₂ is PEP carboxylase, forming a 4-carbon compound.
• This is different from C3 plants, where Rubisco fixes CO₂ first.
• PEP carboxylase has high affinity for CO₂ and does not react with O₂.
• Important for efficient photosynthesis in hot and dry climates.

Last verified on 12-02-2026

Explanation

• Sorghum is a cereal crop grown for food, fodder, and biofuel.
• Its flowers are arranged in a panicle inflorescence, a branched cluster of flowers.
• Panicles help in efficient pollination and seed formation.
• Commonly grown in arid and semi-arid regions.
• Important for human consumption and livestock feed.

Last verified on 12-02-2026

Explanation

• Botanical Name: Gossypium hirsutum
• Common Name: American / Upland cotton
• Global Share: ~90% of world cotton production
• Fiber Type: Medium to long staple
• Main Use: Textile and yarn industry

Additional information:

• Gossypium arboreum — Desi cotton
• Gossypium barbadense — Egyptian cotton

Last verified on 05-02-2026

Explanation

• Soil salinity occurs when excess salts accumulate in soil, reducing fertility.
• Gypsum (Calcium sulfate, CaSO₄·2H₂O) is used to treat saline soils.
• It replaces sodium ions with calcium, improving soil structure.
• Helps crops grow better in affected areas.
• Commonly used in agriculture for soil reclamation.

Last verified on 12-02-2026

Explanation

• Tikka disease is a fungal disease affecting groundnut (peanut) crops.
• Caused by Cercospora arachidicola.
• Leads to leaf spots, defoliation, and reduced yield.
• Major concern in tropical and subtropical regions.
• Early detection and resistant varieties help control it.

Last verified on 12-02-2026

Explanation

• Insects are part of the class Insecta in the animal kingdom.
• They have 3 body parts: head, thorax, and abdomen.
• Most insects have 6 legs and 4 wings.
• They are the largest group of animals on Earth.
• Examples: Butterfly, Bee, Grasshopper, Dragonfly.

Last verified on 12-02-2026

Explanation

• Rhizobium bacteria live in root nodules of leguminous plants (e.g., peas, beans).
  • They convert atmospheric nitrogen (N₂) into ammonia (NH₃), a usable form for plants.
  • This process is called nitrogen fixation.
  • It enriches soil fertility naturally.
  • Essential for plant growth and agriculture.

Last verified on 12-01-2026

Explanation

• Phenotype means the visible appearance or expressed traits of an organism.
• It includes features like height, eye color, and shape.
• It is the result of genotype + environment.
• What we can observe directly is phenotype.
• Used widely in genetics studies.

Last verified on 12-02-2026

Explanation

• Protein foods come from both animal and plant sources.
  • Animal sources include seafood, meat, poultry, and eggs.
  • Plant sources include beans, peas, lentils, nuts, seeds, and soy products.
  • These foods help in body growth and tissue repair.
  • Protein is an essential nutrient.

Last verified on 12-02-2026