Q.6
ICAR AIEEA PG Entomology 09 July 2023 (Shift 1) Paper (Q.56)
MCQ (Single Correct) +4 −1
Citrus canker is a disease caused by:
सिट्रस कैंकर (Citrus canker) किसके द्वारा होने वाला रोग है?

Etiology of citrus diseases:

  • Citrus canker is a severe bacterial disease caused by the Gram-negative bacterium Xanthomonas axonopodis pv. citri (syn. Xanthomonas citri subsp. citri).
  • It causes raised corky necrotic lesions on leaves, stems, twigs, and fruits, surrounded by a characteristic yellow chlorotic halo. The citrus leaf miner (Phyllocnistis citrella) exacerbates the disease by creating epidermal feeding galleries that serve as bacterial infection courts.
Hence, Citrus canker is caused by Bacteria.

नींबू वर्गीय फलों के रोग एवं उनके कारक:

  • सिट्रस कैंकर नींबू वर्गीय फलों का एक अत्यंत गंभीर जीवाणु जनित रोग है, जो ग्राम-नेगेटिव जीवाणु जैन्थोमोनास एक्सोनोपोडिस पीवी. सिट्राई (Xanthomonas axonopodis pv. citri) द्वारा होता है।
  • इसमें पत्तियों, टहनियों और फलों पर उभरे हुए खुरदुरे कॉर्क जैसे भूरे धब्बे बनते हैं जिनके चारों ओर पीला घेरा (Yellow halo) होता है। सिट्रस लीफ माइनर कीट इस जीवाणु के प्रवेश को सुगम बनाता है।
अतः सही उत्तर जीवाणु (Bacteria) है।
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Entomology, Beneficial Insects, Nematology & Pest Management

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Beneficial Insects II - Sericulture and Lac Culture: Silkworm Rearing, Moriculture, Lac Insect Biology and Processing Biological Control: Predators, Parasitoids (Trichogramma, Bracon), Hyperparasitoids and Conservation Pests of Cereals, Millets and Pulses: Rice, Wheat, Maize, Sorghum, Gram, Pigeonpea Orders Apterygota and Exopterygota: Odonata, Orthoptera, Dictyoptera, Isoptera, Thysanoptera, Hemiptera Beneficial Insects I - Apiculture: Honeybee Species, Social Organization, Bee Pasture, Diseases and Beekeeping Nematode Management: Cultural, Chemical (Nematicides), Biological, Entomopathogenic Nematodes (EPN Steinernema, Heterorhabditis) Insect Reproductive System, Spermatogenesis, Oogenesis, Types of Reproduction and Metamorphosis Plant Nematology II: Taxonomy, Major Nematode Orders (Tylenchida, Dorylaimida), Biology and Life Cycles Pests of Horticultural Crops: Vegetables, Fruit Trees, Plantation Crops, Spices and Flowers Orders Endopterygota: Neuroptera, Coleoptera, Diptera, Lepidoptera, Hymenoptera Integrated Pest Management (IPM): Cultural, Physical, Mechanical, Regulatory (Plant Quarantine) Controls Medical, Veterinary, Household Pests and Non-Insect Pests (Mites, Rodents, Birds) Insect Thorax Morphology: Pterothorax, Legs and Types, Wings, Venation and Coupling Mechanisms Microbial Control: Bacillus thuringiensis, NPV, GV, Entomopathogenic Fungi (Beauveria, Metarhizium) Insect Ecology: Abiotic Factors (Temperature, Humidity, Light), Biotic Factors, Thermal Thresholds and Life Tables Pests of Oilseeds, Commercial Crops and Fiber Crops: Cotton, Sugarcane, Mustard, Groundnut, Soybean Major Plant Parasitic Nematodes: Root-Knot (Meloidogyne), Cyst (Heterodera, Globodera), Reniform, Lesion, Ear-Cockle Insect Taxonomy: Principles of Zoological Nomenclature (ICZN), Hierarchy and Diagnostic Keys Host Plant Resistance (HPR): Non-preference (Antixenosis), Antibiosis, Tolerance and Mechanisms Insect External Morphology: Head, Suture, Tentorium, Eyes, Antennae and Types Insect Mouthparts: Biting-Chewing, Piercing-Sucking, Sponging, Siphoning, Chewing-Lapping Insect Integument: Cuticle Layers, Sclerotization, Chitin Chemistry and Molting Physiology Insecticide Mode of Action: AChE Inhibitors, Voltage-Gated Sodium Channels, GABA, Nicotinic Receptors, RyR Insecticide Formulations, Toxicity (LD50, LC50), Bioassay, Residues, Safety and Insecticides Act 1968 Stored Grain Pests: Primary, Secondary Beetles and Moths, Storage Structures and Fumigation Management Plant Nematology I: History, Morphology, Anatomy, Digestive, Excretory and Reproductive Systems of Nematodes History of Entomology in India, Landmarks, Pioneers and Entomological Institutions Insect Excretory and Nervous Systems: Malpighian Tubules, Cryptonephridia, Brain, Nerve Cord and Sense Organs Population Dynamics, Pest Surveillance, Forecasting, Sampling Methods and ETL/EIL Economics Semio-Chemicals: Pheromones (Sex, Aggregation, Alarm), Kairomones, Allomones, Traps and Mating Disruption Insect Abdomen Morphology, Segments, Male and Female Genitalia, Ovipositor Types and Appendages Insect Digestive System: Foregut, Midgut, Hindgut, Peritrophic Membrane, Filter Chamber and Nutrition Insect Circulatory and Respiratory Systems: Hemolymph, Dorsal Vessel, Spiracles and Tracheal System Insect Endocrine System, Neurohormones, Ecdysone, Juvenile Hormone and Diapause Physiology Chemical Control: Classification of Insecticides (OPs, OCs, Carbamates, Synthetic Pyrethroids, Neonicotinoids)
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