Uncategorized By Vijay Wardhan • December 8, 2024 1. Mixed cropping helps : To increase the nitrogen content of the soil In effective control of the spread of infectious diseases To increase the yield To increase the nitrogen and phosphorus content of the soil Explanation:Mixed cropping can help control the spread of infectious diseases by reducing the density of susceptible hosts and creating a more diverse ecosystem that hinders pathogen spread. 2. There is a class of phenolic compounds produced by the host plant in response to fungal infections : Gibberellins Arbutin Phytoalexins Aflatoxins Explanation:Phytoalexins are antimicrobial and often antioxidative substances synthesized by plants in response to pathogen attack. They play a crucial role in the plant’s defense mechanisms. 3. Which of the following does not contain chlorophyll? Algae Fungi Pteridophyta Bryophyta Explanation:Fungi do not contain chlorophyll and cannot perform photosynthesis. They obtain nutrients through absorption, unlike algae, bryophytes, and pteridophytes that contain chlorophyll. 4. Which one of the following belong to cryptogams only: Bryophytes, Pteridophytes and gymnosperms Spirogyra, Yeast, Moss, Fern Mango, Wheat, Pine, Christmas tree Thallophytes, Bryophytes, Angiosperms Explanation:Cryptogams are non-seed-bearing plants and include groups like algae (Spirogyra), fungi (Yeast), bryophytes (Moss), and pteridophytes (Fern). These groups reproduce by spores and do not produce flowers or seeds. 5. Vascular tissue is found in : Bryophyta Thallophyta Lichens Pteridophyta Explanation:Pteridophytes have vascular tissues (xylem and phloem) that transport water and nutrients. This feature is absent in Thallophyta, Bryophyta, and Lichens. 6. Which of the following is a monocot? Pea Rice Mustard Potato Explanation:Rice is a monocot, characterized by having a single cotyledon in the seed. Monocots also typically have parallel leaf venation and scattered vascular bundles. 7. Ovary is absent in : Neem Cycas Mango Wheat Explanation:Cycas, a gymnosperm, does not have an ovary. In gymnosperms, seeds are not enclosed within an ovary, unlike in angiosperms where the ovary encloses the seeds. 8. Which of the following causes smut disease in cultivated plants? Cystopus Puccinia Phytophthora Albugo Explanation:Albugo is a genus of oomycetes that causes white rust and smut diseases in various cultivated plants. 9. Which one of the following is a monocot? Mango Palm Pine Fern Explanation:Palm is a monocot, characterized by having a single cotyledon in the seed. Monocots also typically have parallel leaf venation and scattered vascular bundles. 10. Body disorders due to harmful physiological changes are known as : Pathology Disease Susceptibility Infection Explanation:Diseases are disorders caused by harmful physiological changes in an organism, leading to impaired function and health. 11. A disease is abnormal state that may result due to : Mineral Environment All of these Pathogen Explanation:Diseases can be caused by various factors including environmental conditions, mineral deficiencies, or pathogens such as bacteria, viruses, and fungi. 12. Smut of maize is caused by : Ustilago maydis Ustilago avenae Ustilago nuda Ustilago hordei Explanation:Smut of maize, also known as corn smut, is caused by the fungus Ustilago maydis, which infects maize plants and forms characteristic galls. 13. In plants, the substances which accumulate around the site of infection are : Phytoalexins Pathogenesis-related proteins All of the above Saponins Explanation:Pathogenesis-related proteins, phytoalexins, and saponins are all substances that accumulate around infection sites in plants, playing a role in the plant’s defense mechanisms. 14. Bryophyta have been placed in cryptogams because: They do not produce flowers They are heterotrophic The flowers are hidden They do not have true roots Explanation:Bryophytes are classified as cryptogams because they do not produce flowers or seeds. They reproduce by spores and have simple structures compared to flowering plants. 15. The disease occurring more or less regularly from year to year in a particular locality is referred to as : Epidemic disease Endemic disease Pandemic disease Sporadic disease Explanation:An endemic disease is one that is consistently present in a particular geographic area or population. It occurs regularly and at predictable rates. 16. The smut mycelium which initiates the infection is usually : Haploid Dikaryotic Diploid Triploid Explanation:Smut fungi typically have a dikaryotic mycelium, meaning each cell contains two genetically distinct nuclei, which is crucial for initiating infection. 17. Embryo formation is not known in : Bryophytes Thallophytes Phanerogams Pteridophytes Explanation:Thallophytes do not form embryos. This group includes algae and fungi, which reproduce through spores or other means without developing an embryo. 18. Small epidermal swellings due to infection are called : Shot holes Burnts Eclema Eczema Explanation:Eclema refers to small, raised swellings on the epidermis of plants, often caused by infections or other stress factors. 19. A branch of science that deals with nature, symptoms, development and control of plant diseases is called : Mycology Pathology Phytopathology Epidemiology Explanation:Phytopathology is the study of plant diseases, including their causes, symptoms, development, and control measures. 20. Which of the following is not a fungal disease? Red rust of tea Rust disease of crucifers Rust of wheat Rust of coffee Explanation:Red rust of tea is caused by the alga Cephaleuros virescens, not by a fungus. The other diseases listed are caused by fungal pathogens. 21. Which of the following are included in Tracheophyta? Pteridophyta, Gymnosperms and Angiosperms Algae and Fungi Algae and Bryophytes Gymnosperms and Angiosperms Explanation:Tracheophyta includes plants with vascular tissues, such as pteridophytes, gymnosperms, and angiosperms. Algae and bryophytes lack vascular tissues and are not included in this group. 22. Ovules are not found enclosed in ovary in : Bryophyta Thallophyta Angiosperms Gymnosperms Explanation:In gymnosperms, ovules are exposed and not enclosed within an ovary. This is a defining characteristic that sets them apart from angiosperms, where ovules are enclosed in an ovary. 23. Propagating materials like seeds, tubers, grafts and bulbs can be kept free of pathogens by : Deep saving Giving heat, gas or chemical treatment Giving alkali treatment Giving acid treatment Explanation:Heat, gas, or chemical treatments are effective methods to sterilize propagating materials and keep them free from pathogens, ensuring healthy plant growth. 24. Red rot of sugarcane is caused by : Colletotrichum falcatum Alternaria solani Cercospora arachidicola Helminthosporium oryzae Explanation:Red rot of sugarcane is caused by the fungus Colletotrichum falcatum, leading to significant damage and yield loss in sugarcane crops. 25. Black rust of wheat is caused by: Puccinia Yeast Rhizopus Penicillium Explanation:Black rust of wheat, also known as stem rust, is caused by the fungus Puccinia graminis. It is a serious disease that affects wheat crops worldwide. 26. When a diseased plant is legally stopped from export, this is done under : Biological prevention Curative check Crop improvement Quarantine measure Explanation:Quarantine measures are legal actions taken to prevent the export of diseased plants, thereby controlling the spread of plant diseases. 27. The disease symptom necrosis refers to : Dead corky areas Rough crust-like lesions Dead tissues Burnt areas on the leaves Explanation:Necrosis is the death of plant cells or tissues, often resulting in dark, dead areas on leaves, stems, or other parts of the plant. It can be caused by various factors including pathogens and environmental stress. 28. Cryptogams include : Bryophytes Thallophytes All of these Pteridophytes Explanation:Cryptogams are non-seed-bearing plants and include Thallophytes, Bryophytes, and Pteridophytes. They reproduce by spores and do not produce flowers or seeds. 29. If a disease appear on large scale after a long interval it is : Epiphytotic Epidemic Endemic Sporadic Explanation:An epiphytotic disease is one that appears suddenly and spreads rapidly over a large area, affecting many plants at the same time. This term is analogous to an epidemic in humans. 30. Pteridophytes are also known as : Vascular cryptogams Seed plants Horse tails Club mosses Explanation:Pteridophytes are termed vascular cryptogams because they are non-seed-bearing plants with vascular tissues. They include ferns and their relatives, which are distinct from seed plants. 31. An excessive enlargement of diseased organ because of increase in the number of cells is called : Hyperplasia Hypertrophy Damping off Necrosis Explanation:Hyperplasia refers to the increase in the number of cells in an organ or tissue, causing its enlargement. This is a common response to a stimulus and can be seen in various diseases. 32. Which of the following is the most destructive enemies of mankind? Rust of wheat Apple scab Damping off disease Early blight of potato Explanation:Rust of wheat, caused by Puccinia species, is one of the most destructive plant diseases affecting wheat crops, leading to significant yield losses and threatening food security. 33. Which among the following is a shrub? Rubber plant Mustard China rose Hydrilla Explanation:China rose, or Hibiscus, is a shrub. Shrubs are plants with multiple woody stems and are generally smaller than trees but larger than herbs. 34. Liverworts are included in : Fungi Bryophyta Schizomycophyta Pteridophyta Explanation:Liverworts are a type of bryophyte. They are non-vascular plants that reproduce via spores and thrive in moist environments. 35. Severe famine of West Bengal of 1942-43 was due to destruction of rice crop by a fungus called : Helminthosporium Penicillium Puccinia Rhizopus Explanation:The Bengal famine of 1942-43 was caused by the destruction of rice crops by the fungus Helminthosporium oryzae, leading to severe food shortages and starvation. 36. Which of the following statements is not correct? The smut spores cause enormous loss by damaging the crops The smuts commonly attack the reproductive structures of the plant The life cycle of smut is considerably less complicated than that of rusts The smuts commonly attack stem, leaves and roots Explanation:Smuts primarily attack the reproductive structures of plants, such as flowers and seeds, rather than stems, leaves, and roots. 37. The pathogen that causes covered smut of Sorghum is : Sphacelotheca Colletotrichum Cercospora Helminthosporium Explanation:Sphacelotheca is the pathogen responsible for covered smut in Sorghum, a disease that affects the grains and can lead to significant crop losses. 38. Most primitive embryophytes are placed in : Bryophyta Trachaeophyta Cyanophyta Thallophyta Explanation:Bryophytes are considered the most primitive embryophytes. They are non-vascular plants that reproduce via spores and are often found in moist environments. 39. Which of the following does not help in penetration of pathogen into the host? Piricularin Pectinase Ligninase Cutinase Explanation:Piricularin is not involved in the penetration of pathogens into the host. Enzymes like pectinase, cutinase, and ligninase help break down plant cell walls to facilitate pathogen entry. 40. Embryophyta includes : Bryophyta and Pteridophyta Algae and Fungi Angiosperm only All the plants except Thallophyta Explanation:Embryophyta includes all land plants that develop an embryo, excluding Thallophyta. This group encompasses bryophytes, pteridophytes, gymnosperms, and angiosperms. 41. Aflatoxin is produced as a product in : Aspergillus Penicillium Streptomyces Pathogenic bacteria Explanation:Aflatoxins are toxic metabolites produced by certain species of Aspergillus fungi, particularly Aspergillus flavus and Aspergillus parasiticus. MULTIPLE CHOICE QUESTIONS 42. The scientist who is famous for his research on rust fungi in India is : K.C. Mehta Butler Mundker Sivadasan Explanation:K.C. Mehta is renowned for his extensive research on rust fungi in India, contributing significantly to the understanding and management of rust diseases. 43. Chief constituents of bordeaux mixture are : Calcium oxide, copper sulphate, water Calcium sulphate, copper carbonate and water None of the above Calcium carbonate, copper carbonate and water Explanation:Bordeaux mixture is a fungicide composed of calcium oxide, copper sulphate, and water, widely used to control fungal diseases in plants. 44. Spermatophyta are characterized by producing: Seeds Sperms Ciliated antherozoids Protonema Explanation:Spermatophyta, or seed plants, are characterized by their production of seeds. This group includes both gymnosperms and angiosperms, which use seeds for reproduction. 45. Late blight of potato is caused by : Fusarium moniliforme Albugo candida Alternaria solani Phytophthora infestans Explanation:Late blight of potato is caused by the oomycete Phytophthora infestans. This pathogen is notorious for causing the Irish potato famine and continues to be a significant threat to potato crops worldwide. 46. A perennial that bears flowers and fruits once in a life time is known as : Biennial Annual Monocarpellary Monocarpic Explanation:Monocarpic plants are perennials that flower and fruit only once in their lifetime. After producing seeds, they typically die. 47. When an infection is very wide in occurrence, it is called : Wide Massive Localized Systemic Explanation:A systemic infection spreads throughout the entire plant, affecting multiple tissues and organs, in contrast to localized infections that are confined to specific areas. 48. Oswald Tippo’s classification was based on : Presence or absence of vascular tissues Development of embryo None of the above Both (a) and (b) Explanation:Oswald Tippo’s classification considered both the development of the embryo and the presence or absence of vascular tissues. This dual criterion helped in categorizing plants more precisely. 49. Fruits are not found in : Dicots Angiosperms Cycas Monocots Explanation:Cycas, a gymnosperm, does not produce fruits. Fruits are a characteristic feature of angiosperms, which enclose seeds within a fruit. 50. Leaves of pea show white powdery patches due to the growth of fungal mycelium with conidia and conidiophores. These are the symptoms of : Damping off Blight Rust Mildew Explanation:Mildew refers to a fungal disease that presents as white or gray powdery patches on the surface of leaves and stems. It is caused by fungi such as Erysiphales. 51. Seeds are characteristically found in : Pteridophytes Bryophyta Spermatophytes Fungi Explanation:Spermatophytes, or seed plants, produce seeds as a means of reproduction. This group includes both gymnosperms and angiosperms, unlike bryophytes, pteridophytes, and fungi. 52. A diseased leaf shows some areas with dead tissue. This symptom is often referred to as : Necrotic spots Chlorosis Galls Blight Explanation:Necrotic spots are areas of dead tissue on leaves or other plant parts, often caused by infections, toxins, or adverse environmental conditions. 53. Banana bunchy top is caused by : deuteromycetes mycoplasma virus Xanthomonas Explanation:Banana bunchy top is caused by the Banana bunchy top virus (BBTV). This virus leads to stunted growth and “bunchy” appearance of leaves, severely affecting the productivity of banana plants. 54. Green plants are classified as : Heterotrophs Omnivores Autotrophs Herbivores Explanation:Green plants are autotrophs because they produce their own food through photosynthesis. They convert light energy into chemical energy, unlike heterotrophs that rely on other organisms for food. 55. Who is known as ‘Father of Taxonomy’? Linnaeus Huxley None of these Theophrastus Explanation:Carl Linnaeus is known as the ‘Father of Taxonomy’ for his work in developing a system for naming, ranking, and classifying organisms that is still in use today. 56. Club moss is the common name of : Lycopodium Funaria Sphagnum Selaginella Explanation:Lycopodium is commonly known as club moss. It belongs to the group of pteridophytes and is distinct from true mosses like Funaria and Sphagnum. 57. Which of the following is not a viral disease? Tobacco mosaic Red rot of sugarcane Tristeza disease of Citrus Leaf curl of papaya Explanation:Red rot of sugarcane is a fungal disease caused by Colletotrichum falcatum, not a viral disease. The other diseases listed are caused by viruses. 58. Which of the following is not a correct match? Cercospora-Tikka disease of groundnut Helminthosporium-Bengal famine Melampsora-Red rust of tea Aspergillus parasiticus-Aflatoxin Explanation:Melampsora is not associated with red rust of tea. Red rust of tea is caused by Cephaleuros virescens, a green alga. 59. A control measure prior to the appearance of a particular disease comes under : Prophylactic measure Therapentic measure Predisposition measure Curative measure Explanation:Prophylactic measures are preventive actions taken to prevent the onset of disease. These measures are implemented before any signs of the disease appear. 60. Woody climbers are known as : Lianas Twiners Creepers Climbers Explanation:Lianas are woody climbers that use other structures for support as they grow upwards. They are distinct from twiners, climbers, and creepers, which have different growth habits. 61. A plant which reproduces by spores, has vascular tissue but lacks flowers should belong to : Pteridophyta Bryophyta Gymnosperms Thallophyta Explanation:A plant that reproduces by spores, has vascular tissues, and lacks flowers is a pteridophyte. This group includes ferns and their relatives, distinct from bryophytes, thallophytes, and gymnosperms. 62. ‘Snakes of Plant Kingdom’ is : Ferns Blue-green algae Pinus Mosses Explanation:Ferns are often referred to as the ‘Snakes of the Plant Kingdom’ due to their long, creeping rhizomes and fronds that unfurl in a coiled manner resembling a snake. 63. Which are non-seed-bearing vascular plants? Pteridophytes Bryophyte Angiosperms Gymnosperms Explanation:Pteridophytes are non-seed-bearing vascular plants. They reproduce via spores and have vascular tissues, unlike bryophytes that lack vascular tissues and gymnosperms and angiosperms that produce seeds. 64. Chemicals which are applied soon after the outset of infection, suppress the development of pathogen, thus curing the plant, are called : Eradicants Therapeutants Fumicides Protectants Explanation:Therapeutants are chemicals applied after the onset of infection to suppress the development of pathogens and cure the plant. They differ from protectants, which are applied preventively. 65. Rice, pea, potato are : Herbs Trees Xerophytes Annuals Explanation:Rice, pea, and potato are classified as herbs. They are non-woody plants with soft stems and are distinct from trees, annuals, and xerophytes. 66. Atracheata term has been used by Oswald Tippo for : Pteridophyta Bryophyta Angiosperms Gymnosperms Explanation:Oswald Tippo used the term “Atracheata” to describe Bryophyta, which lack vascular tissues. This term highlights their primitive nature compared to other plant groups with vascular systems. 67. Helminthosporium oryzae was the cause of disaster : Collapse of French industry in 1870 Irish famine is 1845 Bengal famine in 1943 Displacement of planters in Ceylon in 1867 Explanation:Helminthosporium oryzae caused the Bengal famine of 1943 by devastating rice crops, leading to widespread food shortages and famine. 68. Rigid cell wall and embryo formation characterise kingdom : Monera Protista Plantae Animalia Explanation:The kingdom Plantae is characterized by organisms with rigid cell walls made of cellulose and the formation of embryos. These features distinguish them from other kingdoms like Protista, Monera, and Animalia. 69. A part of pathogen that is transmitted to the host is termed as : Infection Disease Incubation Inoculum Explanation:Inoculum refers to the part of a pathogen, such as spores or bacteria, that is transmitted to a host plant to initiate infection. 70. The plants with soft and delicate stems, about a meter tall are known as : Shrubs Herbs Climbers Trees Explanation:Herbs are plants with soft, delicate stems that are typically about a meter tall. They are distinct from shrubs, trees, and climbers, which have different growth forms. 71. All but one group are included in tracheophyta; which group is this : Pteridophyta Thallophyta Angiosperms Gymnosperms Explanation:Thallophyta are not included in Tracheophyta because they lack vascular tissues. Tracheophyta includes plants with vascular systems, such as pteridophytes, gymnosperms, and angiosperms. 72. Quarantine regulations are concerned with: Prevention of entry of diseased plants in the country Spraying of diseased plants with insecticides Promotion of dry farming in sandy soil Growing of fruit trees in every state Explanation:Quarantine regulations aim to prevent the introduction and spread of diseased plants into a country, thereby protecting local agriculture from potential outbreaks. 73. Ergot is obtained from : Cystopus Claviceps Rhizobium Ustilago Explanation:Ergot is a fungal disease caused by Claviceps species, which infects cereal grains and produces toxic alkaloids. 74. A plant bears fruit, has a column of vascular bundle and a tap root system. This plant is a : Angiosperm and dicot Gymnosperm Angiosperm and monocot Gymnosperm and dicot Explanation:The plant described is an angiosperm and a dicot. Dicots typically have a tap root system, vascular bundles in a ring, and produce fruits. 75. Gymnosperms could also be called as: Amphibians of the plant kingdom Vascular cryptogams Phanerogams without ovary Botanical curiosities Explanation:Gymnosperms are seed-producing plants (phanerogams) that do not have their ovules enclosed in an ovary. This characteristic differentiates them from angiosperms, which have enclosed ovules. 76. In which group would you place a plant that reproduces by spores, develops embryo but plant body remains undifferentiated into root, stem and leaves? Fungi Algae Gymnospermae Hepaticae Explanation:Hepaticae, or liverworts, reproduce by spores, develop an embryo, and have a plant body that is not differentiated into root, stem, and leaves. This distinguishes them from other groups like algae and fungi. 77. Which of the following is the kingdom of multicellular producers? Protista Monera Animalia Plantae Explanation:The kingdom Plantae consists of multicellular producers that perform photosynthesis. They convert light energy into chemical energy, distinguishing them from other kingdoms. 78. Citrus canker is caused by : Xanthomonas oryzae Pseudomonas rubrilineans Pseudomonas solanacearum Xanthomonas citri Explanation:Citrus canker is a bacterial disease caused by Xanthomonas citri. It produces lesions on the leaves, stems, and fruits of citrus plants, leading to reduced fruit quality and yield. 79. There are some dead and corky areas with definite margins on the stem, branches and fruits of lemon. This disease should be : Scab Canker Rust Curl Explanation:Canker is a disease characterized by sunken, dead areas on stems, branches, and fruits. It is commonly caused by bacteria or fungi and can lead to significant damage in affected plants. 80. Which group of plants is called “Amphibians of Plant World”? Gymnosperms Bryophyta Fungi Algae Explanation:Bryophytes are referred to as the “Amphibians of the Plant World” because they require water for reproduction and thrive in moist environments, similar to how amphibians live both in water and on land. 81. Roots are absent in : Gymnosperms Pteridophyta Bryophyta Dicots Explanation:Bryophytes lack true roots and instead have structures called rhizoids for anchorage. This differentiates them from other plant groups that possess true roots. 82. Pythium debaryanum is the causative agent of: Black wart disease of potato Powdery mildew Soft rot of sweet potato Damping off of seedling Explanation:Pythium debaryanum is a soil-borne pathogen that causes damping-off, a disease that affects seedlings, leading to their collapse and death. 83. According to Woese, fungi were placed in the domain : Archae Bacteria Plantae Eukarya Explanation:Woese classified fungi in the domain Eukarya, which includes organisms with complex, membrane-bound cells. Fungi are distinct from bacteria and archaea, which are prokaryotes. 84. The causal organism of early blight of potato is : Alternaria solani Albugo candida Phytophthora infestans Cercospora personata Explanation:Early blight of potato is caused by the fungus Alternaria solani, which leads to dark, concentric spots on leaves, stems, and tubers. 85. Vascular cryptogam is the term used for : Pteridophytes Algae Angiosperms Gymnosperms Explanation:Pteridophytes are called vascular cryptogams because they possess vascular tissues but do not produce seeds. This term distinguishes them from non-vascular cryptogams like algae and bryophytes. 86. Red rot of sugarcane is caused by : Helminthosporium Puccinia Colletotrichum Ustilago Explanation:Red rot of sugarcane is a fungal disease caused by Colletotrichum falcatum. It is a major disease affecting sugarcane crops, leading to significant yield losses. 87. Oswald Tippo’s classification is: Natural Artificial None of these Phylogenetic Explanation:Oswald Tippo’s classification is phylogenetic, meaning it is based on the evolutionary relationships among plant groups. This approach considers both the development of the embryo and the presence or absence of vascular tissues. 88. The inability of a plant to resist the effects of a pathogen or any other damaging factors is known as : Predisposition Susceptibility Virulence Resistance Explanation:Susceptibility is the inability of a plant to resist the effects of pathogens or other damaging factors, making it more prone to disease. 89. Which of the following organisms has characters of both animals and plants? Euglena Blue-green algae Cycas Moss Explanation:Euglena exhibits characteristics of both plants and animals. It has chloroplasts for photosynthesis like plants but can also move and consume food like animals. 90. When the seeds are borne on megasporophylls and are not enclosed in a fruit, the plant belongs to : Monocotyledons Dicotyledons Pteridophytes Gymnosperms Explanation:Gymnosperms produce seeds on megasporophylls without enclosing them in a fruit. This is a key characteristic that differentiates them from angiosperms, which enclose seeds within fruits. 91. Etiology includes the study of : Pathogen Host Disease Parasite Explanation:Etiology is the study of the causes of diseases, focusing on the pathogens responsible for causing the diseases. 92. Multicellular and jacketed sex organs are found in : Algae Mosses None of these Fungi Explanation:Mosses, which are bryophytes, have multicellular and jacketed sex organs. This feature is not found in algae or fungi, making mosses unique in this aspect. 93. The tallest living gymnosperm tree in the world belongs to : Sequoia sempervirens Eucalyptus globulus Pinus longaeva Wolffia punctata Explanation:Sequoia sempervirens, also known as the coast redwood, is the tallest living gymnosperm tree in the world. These trees can reach heights of over 300 feet. 94. In which of the following plants would you place heterotrophs like slime moulds, rusts, mushrooms, etc.? Monera Protists Animalia Fungi Explanation:Slime molds, rusts, and mushrooms are classified as fungi. They are heterotrophs that obtain nutrients through absorption, unlike protists, monera, and animals. 95. Disease resistant plant varieties can be produced by : Hormonal treatment Heat treatment Crossing with wild varieties of plants Colchicine treatment Explanation:Crossing cultivated plants with wild varieties can introduce genes that confer resistance to diseases, thereby producing disease-resistant plant varieties. 96. Downy mildew disease is caused by : Puccinia Peronospora Phytophthora Albugo Explanation:Downy mildew is caused by various species of the genus Peronospora. This disease affects a wide range of plants, leading to the appearance of downy growth on the underside of leaves and significant crop damage. 97. Which of the following plants does not belong to Embryophyta? Dryopteris Funaria Ulothrix Cycas Explanation:Ulothrix is an alga and does not belong to Embryophyta, which includes plants that develop an embryo. Funaria, Dryopteris, and Cycas are all embryophytes. 98. Which part of the plant is not affected by Albugo? Root Stem Flower Leaf Explanation:Albugo, the causative agent of white rust, primarily affects the aerial parts of the plant such as leaves, stems, and flowers, but not the roots. 99. Maximum diversity of life forms occurs in : Deserts Tropical rain forests Grasslands Temperate forests Explanation:Tropical rainforests have the highest biodiversity of any terrestrial ecosystem. They provide a wide range of habitats and resources, supporting a vast array of species. 100. Leaf spot of groundnut is caused by : Piricularia Sclerospora Cercospora Helminthosporium Explanation:Cercospora arachidicola is the pathogen responsible for leaf spot disease in groundnut. This disease is characterized by circular lesions on the leaves, which can lead to significant yield loss if not controlled. 101. Club moss and Peat moss belong to: Fungi and Pteridophytes Bryophytes only Pteridophytes and Bryophytes Algae and Pteridophytes Explanation:Club mosses are pteridophytes, while peat mosses are bryophytes. Both groups are non-seed-bearing plants but belong to different classifications within cryptogams. Loading … Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment * Name * Email * Website Save my name, email, and website in this browser for the next time I comment.
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