Past Questions — 2025

The Netherlands is globally recognized as the hub of the floriculture industry. It is the world leader in both the production and, more significantly, the trading of cut flowers. The country hosts the Royal FloraHolland, the largest flower auction in the world, which facilitates the global distribution of cut flowers. While other countries like Colombia, Ecuador, and Kenya are major producers, the Netherlands dominates the logistics, trading, and high-tech greenhouse production of cut flowers. - USA: A major consumer and producer of some varieties, but not the global trading leader. - Israel: A leader in agricultural technology and seed development, but not the largest in cut flower volume/trade. - India: A growing producer of cut flowers, but operates on a much smaller global trade scale compared to the Netherlands.

Arka Khyati is a high-yielding variety of Onion (Allium cepa) developed by the Indian Agricultural Research Institute (IARI). It is specifically bred for its improved yield, quality, and resistance to common pests and diseases. Breakdown of options: - a. Onion: Correct. Arka Khyati is a recognized variety of onion. - b. Chilli: Incorrect. Common 'Arka' varieties of chilli include Arka Kyati (though sometimes confused, the specific nomenclature for the onion variety is well-documented) or others like Arka Meghana. - c. Tomato: Incorrect. Popular 'Arka' tomato varieties include Arka Rakshak and Arka Samrat. - d. Okra: Incorrect. Okra varieties typically follow different naming conventions or specific regional breeding programs.

Gladiolus is a genus of perennial flowering plants that propagate vegetatively through modified underground stems known as corms. A corm is a swollen, vertical, fleshy stem base that stores nutrients to support the plant's growth and flowering in the next season. Why other options are incorrect: - b. Bulb: A bulb (e.g., Onion, Tulip) consists of a short stem surrounded by fleshy scale leaves. While similar to corms, gladioli specifically produce corms. - c. Rhizome: A rhizome (e.g., Ginger, Turmeric) is a horizontal underground stem. - d. Tuber: A tuber (e.g., Potato) is a thickened part of a stem or root used for food storage, typically lacking the organized structure of a corm.

Arka Archana is a developed variety of Hibiscus (Hibiscus rosa-sinensis). It was developed by the Indian Institute of Horticultural Research (IIHR), Bengaluru. This variety is specifically bred for its ornamental value, characterized by its vibrant flower color and suitability for landscaping and home gardens. Comparing the options: - a. Hibiscus: Correct. Arka Archana is a recognized cultivar of Hibiscus. - b. Aster: Incorrect. Aster varieties typically have different naming conventions (e.g., cultivars like 'Autumn Pride'). - c. Lily: Incorrect. Lily varieties are generally categorized by species (e.g., Oriental, Asiatic) or specific hybrid names. - d. Tulip: Incorrect. Tulip varieties are usually named based on their color or origin (e.g., 'Queen of Night').

The French bean (Phaseolus vulgaris) is a widely studied legume in cytogenetics. Its somatic chromosome number is 2n = 22. This means the diploid number is 22, and the haploid number (n) is 11. Analysis of options: - Option a (18): Incorrect. This is not the chromosome number for Phaseolus vulgaris. - Option b (45): Incorrect. This is an odd number and not characteristic of the diploid state of this species. - Option c (10): Incorrect. This does not match the known cytogenetic data for French beans. - Option d (22): Correct. The established diploid chromosome number for the French bean is 22.

Step-by-step analysis of the botanical names provided in the options: 1. **Acorus calamus**: This is the botanical name for **Sweet flag**. It is a perennial herbaceous plant known for its aromatic rhizomes used in traditional medicine and perfumery. 2. **Dill**: The botanical name for Dill is *Anethum graveolens*. 3. **Aniseed**: The botanical name for Aniseed is *Pimpinella anisum*. 4. **Fenugreek**: The botanical name for Fenugreek is *Trigonella foenum-graecum*. Comparing the given botanical name 'Acorus calamus' with the options, it matches perfectly with 'Sweet flag'.

Arka Nikita is a high-yielding, determinate variety of Tomato developed by the Indian Institute of Horticultural Research (IIHR), Bengaluru. It is characterized by its resistance to leaf curl virus and high productivity. Analysis of other options: - Brinjal: Common 'Arka' varieties include Arka Keshav and Arka Navneet. - Onion: Common varieties include Agrifound or various regional hybrids, but Arka Nikita is not one of them. - Okra: Common varieties include Arka Anamika.

Heterostyly is a genetic polymorphism in which a plant species produces two or more different types of flowers (morphs) that differ in the relative lengths of their styles (pistils) and stamens. This mechanism is an evolutionary adaptation to promote cross-pollination and prevent self-fertilization. 1. **Primula (Primrose):** This is the classic textbook example of heterostyly (specifically distyly). Primula species typically have two types of flowers: 'pin' flowers (long style, short stamens) and 'thrum' flowers (short style, long stamens). This ensures that pollen from a thrum flower is more likely to land on the stigma of a pin flower, and vice versa. 2. **Petunia:** While some species show variations, they are not the primary representative of heterostyly in botanical studies compared to Primula. 3. **Gerbera:** These are composite flowers (Asteraceae) and do not exhibit the specific morphological heterostyly seen in Primula. 4. **Ageratum:** Also a member of the Asteraceae family, it does not exhibit heterostyly.

Fertigation is the process of applying fertilizers through an irrigation system. The suitability of a fertilizer for fertigation depends primarily on its water solubility and its tendency to react with other ions to form precipitates that can clog emitters and drippers. 1. **Nitrogen fertilizers (Option a):** Most nitrogen sources used in fertigation (like Urea or Ammonium Nitrate) are highly water-soluble and move easily through irrigation systems, making them very suitable. 2. **Potassium fertilizers (Option c):** Potassium salts (like Potassium Nitrate or Potassium Sulfate) are generally soluble and compatible with most irrigation systems. 3. **Phosphorus fertilizers (Option b):** Phosphorus is the most problematic nutrient in fertigation. Many phosphorus sources (especially phosphates) have low solubility in certain pH ranges and a high tendency to react with Calcium (Ca) and Magnesium (Mg) present in the water to form insoluble precipitates (like Calcium Phosphate). These precipitates cause scaling and clogging of the drip emitters, making phosphorus fertilizers the least suitable among the three options unless specific acid-treated or highly soluble forms are used.

When evaluating greenhouse glazing materials for 'long term use,' the primary criteria are durability, lifespan, and resistance to degradation. 1. **Glass (Option c):** Glass is the most durable glazing material. It does not degrade under UV radiation, is chemically inert, and can last for decades if not physically broken. It maintains its light transmission properties over time, making it the gold standard for permanent, long-term structures. 2. **Polycarbonate (Option d):** While very strong and durable compared to films, polycarbonate eventually yellows and becomes brittle due to UV exposure (even with UV-stabilized coatings), typically lasting 10-15 years. 3. **Acrylic (Option b):** Similar to polycarbonate, acrylic is a rigid plastic that is susceptible to scratching and gradual degradation from UV rays and temperature fluctuations over time. 4. **Polyvinyl chloride (PVC) film (Option a):** Plastic films are considered temporary or semi-permanent. They are prone to tearing, degradation by UV light, and typically need replacement every 3-5 years. Therefore, in terms of absolute longevity and permanence, glass is the most suitable material.

Pusa Nanha is a renowned dwarf variety of papaya developed by the Indian Agricultural Research Institute (IARI). Due to its dwarf nature (reaching a height of only about 1-1.5 meters), it is specifically designed for high-density planting and pot culture. For commercial field cultivation under high-density planting systems, the recommended spacing is 1.5m × 1.5m. This spacing optimizes the plant population per unit area while ensuring sufficient sunlight penetration and air circulation to prevent fungal diseases and ensure optimal fruit development. Spacings like 2.0m x 2.0m are typically reserved for tall, commercial hybrid varieties, while spacings below 1.5m (like 1.25m) may lead to excessive competition for nutrients and light in a field setting.

In honey bees (Apis species), the sex determination system is known as haplodiploidy. 1. **Drones (Males):** These are developed from unfertilized eggs through a process called parthenogenesis. Because the egg is unfertilized, drones are haploid, meaning they possess only one set of chromosomes (n). 2. **Workers (Females):** These are developed from fertilized eggs (diploid, 2n). Their development into workers rather than queens is determined by their diet (they are fed royal jelly for a short time and then switched to bee bread). 3. **Queens (Females):** These are also developed from fertilized eggs (diploid, 2n). They become queens because they are fed exclusively on royal jelly throughout their larval stage. Therefore, only the drones are developed from unfertilized eggs.

Clove (Syzygium aromaticum) is a spice derived from the flower buds of the clove tree. The commercial part harvested is the immature, unopened flower bud. These buds are picked just before they open and are then dried, which gives them their characteristic nail-like appearance and strong aromatic properties due to the high concentration of eugenol. Analysis of other options: - a. Fruit: While the tree produces berries, the fruit is not the commercial spice used globally. - b. Seed: The seeds are not the part harvested for commercial spice production. - d. Leaves: Although clove leaves are used to extract clove leaf oil, the primary 'commercial part' referred to as the spice 'clove' is the flower bud.

Step-by-step reasoning: 1. The question asks for the causal organism of 'leaf rust' in coffee, which is one of the most economically damaging diseases of coffee worldwide. 2. Hemileia vastatrix (often spelled vestatrix in some texts) is a basidiomycete fungus that causes Coffee Leaf Rust (CLR). It manifests as yellow-orange powdery pustules on the underside of the leaves, leading to premature defoliation and reduced yield. 3. Evaluating other options: - Exobasidium vexans: This fungus causes 'Blister blight' in tea, not rust in coffee. - Fomes noxius: This is generally associated with wood decay or root rot in various tree species, not coffee leaf rust. - Ganoderma lucidum: This is a polypore fungus known as the 'Reishi mushroom' or 'Lingzhi'; it causes white root rot in various woody plants and is not the cause of leaf rust. 4. Therefore, Hemileia vestatrix is the correct pathogen.

Fairy rings are distinct circular patterns of mushrooms or lush green grass often seen in lawns. They are caused by certain species of fungi (most commonly Basidiomycetes, such as Marasmius oreades) that grow outward from a central point in a radial fashion. As the fungal mycelium expands, it decomposes organic matter and releases nitrogen, which often stimulates the growth of the grass, creating a ring of darker green grass. In some cases, the fungus may kill the grass, creating a ring of dead turf. Why other options are incorrect: - Bacteria: While bacteria can cause lawn diseases (like brown patch), they do not grow in the organized, radial mycelial patterns required to form fairy rings. - Insects: Insects may cause patches of damage or 'brown patches' due to feeding, but they do not create the characteristic expanding circular growth pattern associated with fairy rings. - Nematodes: These are microscopic roundworms that typically cause stunted growth or root galling, not large-scale circular surface patterns.

Arka Abhed is a prominent hybrid variety of Brinjal (Eggplant) developed by the Indian Institute of Horticultural Research (IIHR), Bengaluru. It is specifically bred for resistance against the Bacterial Wilt (Ralstonia solanacearum), which is one of the most devastating soil-borne diseases affecting brinjal crops. The prefix 'Arka' is commonly used for varieties developed by IIHR. Analysis of other options: - Tomato: While IIHR has developed many 'Arka' tomato varieties (e.g., Arka Rakshak), Arka Abhed is not one of them. - French bean: These are typically developed as cultivars or hybrids by different breeding programs, not under the Arka Abhed designation. - Cow pea: This is a legume, and its breeding nomenclature differs from the 'Arka' series used for solanaceous vegetables at IIHR.

In potato cultivation, varieties are categorized by their maturity period (early, medium, and late). 1. **Kufri Jyoti** is a widely recognized 'early maturing' variety. It is characterized by a shorter growth cycle, allowing farmers to harvest the crop sooner than medium or late varieties. 2. **Kufri Karan** and **Kufri Chandramukhi** are generally categorized as medium-maturing varieties, often bred for specific resistances (like late blight) or higher yields over a longer period. 3. **Kufri Frysona** is a medium-to-late maturing variety specifically developed for the processing industry (chips and fries) due to its high dry matter content and specific gravity. Therefore, among the given options, Kufri Jyoti is the correct choice for early maturity.

Parthenocarpy is the development of fruit without the fertilization of ovules, resulting in seedless fruits. In the case of the commercial Banana (Musa spp.), the fruit develops without pollination or fertilization, making it a classic example of natural parthenocarpy. Analysis of other options: - Guava: Typically produces seeds through normal fertilization, although some specific cultivars may be seedless, it is not a characteristic feature of the species. - Litchi: Produces a single large seed; it is not parthenocarpic. - Citrus: While some citrus fruits can exhibit stenospermocarpy (where seeds abort), the general characteristic of the genus is not parthenocarpy in the same fundamental way as the commercial banana.

Little leaf of mango is a classic physiological disorder caused by the deficiency of Zinc (Zn). Zinc is an essential micronutrient required for the synthesis of tryptophan, which is a precursor to the plant growth hormone Auxin (specifically Indole-3-acetic acid or IAA). When Zinc is deficient, auxin levels drop, leading to stunted shoot growth and the characteristic development of abnormally small, narrow leaves (little leaves) and shortened internodes, giving the plant a rosette or bunchy appearance. Why other options are incorrect: - Iron (Fe) deficiency typically manifests as interveinal chlorosis (yellowing of young leaves while veins remain green). - Calcium (Ca) deficiency usually results in the death of growing tips (meristems) or blossom end rot in fruits. - Molybdenum (Mo) toxicity is rare in mangoes; Mo deficiency usually affects nitrogen fixation or causes 'whiptail' in other crops like cauliflower.

In fruit physiology, fruits are categorized into two types based on their ripening patterns: climacteric and non-climacteric. 1. **Climacteric Fruits**: These fruits exhibit a burst of ethylene production and a sharp increase in respiration rate during ripening. They can be harvested while unripe and will continue to ripen off the plant. Examples include Mango (Option b), Banana (Option c), and Fig (Option d). 2. **Non-Climacteric Fruits**: These fruits do not show a significant increase in ethylene production or respiration during ripening. They must ripen on the parent plant to reach full quality and do not ripen further once harvested. Citrus fruits, such as the Orange (Option a), are classic examples of non-climacteric fruits. Therefore, among the given options, the Orange is the only non-climacteric fruit.

Bunchy top of banana is a devastating disease caused by the Banana Bunchy Top Virus (BBTV), which belongs to the genus Babuvirus. The disease is characterized by the stunted growth of leaves, which become narrow and stand erect, creating a 'bunched' appearance at the top of the plant. It is primarily transmitted by the banana aphid (Pentalonia nigronervosa). Why other options are incorrect: - a. Fungus: While fungi cause diseases like Fusarium wilt (Panama disease) in bananas, they do not cause Bunchy top. - b. Bacteria: Bacterial diseases in bananas include Bacterial Wilt (Ralstonia solanacearum), but not Bunchy top. - d. Physiological factor: Physiological disorders are caused by nutrient deficiencies or environmental stress, whereas Bunchy top is an infectious disease caused by a biological pathogen.

Tomato Leaf Curl Virus (ToLCV) is caused by a begomovirus (genus Begomovirus, family Geminiviridae). These viruses are specifically transmitted by the whitefly species Bemisia tabaci in a persistent, circulative manner. Reasoning for other options: - a. Thrips: These are primary vectors for Tospoviruses (e.g., Tomato Spotted Wilt Virus), not leaf curl viruses. - c. Aphids: These transmit a wide variety of viruses (e.g., Potato Virus Y), but they are not the vectors for ToLCV. - d. Fruit fly: These are pests that cause direct damage to the fruit through larval feeding and are not known to be vectors for plant viruses like ToLCV.

Garlic varieties are generally classified based on their vernalization requirements and day-length sensitivity for bulb formation. 1. **Agrifound Parvati**: This is a well-known 'Long Day' variety of garlic developed for specific climatic conditions where longer photoperiods are required to trigger the differentiation of the bulb. 2. **Yamuna Safed**: This is typically categorized as a 'Short Day' or 'Intermediate Day' variety, commonly grown in the plains of North India. 3. **G 282**: This is a high-yielding variety but is generally not classified as a primary long-day type in standard agricultural textbooks compared to the Agrifound series. 4. **Agrifound White**: While part of the Agrifound series, 'Parvati' is specifically highlighted in agricultural literature as the representative long-day type among the options provided. Therefore, Agrifound Parvati is the correct answer as it requires longer days to initiate bulb development.

In landscaping, gardening styles are broadly categorized into Formal and Informal. 1. **Formal Style**: Characterized by geometric shapes, symmetry, straight lines, and a sense of human control over nature. - **Mughal Gardens (a)**: Highly formal, featuring the 'Charbagh' (four-fold garden) layout with strict symmetry and water channels. - **Italian Gardens (b)**: Formal, emphasizing terraces, symmetry, and architectural elements like statues and fountains. - **French Gardens (c)**: The epitome of formality (e.g., Versailles), utilizing precise geometry, long vistas, and manicured hedges (topiary). 2. **Informal Style**: Characterized by asymmetrical layouts, curved lines, and an attempt to mimic the natural landscape. - **Japanese Gardens (d)**: These are fundamentally informal. They are designed to evoke nature in a miniaturized, symbolic form, using asymmetrical arrangements of rocks, water, and plants to create a serene, naturalistic environment.

Buttoning is a physiological disorder specifically associated with onion (Allium cepa) cultivation. It occurs when the onion bulb fails to swell and remains small, resembling a button. This disorder is typically caused by environmental stressors such as low temperatures during the bulb formation stage, nitrogen deficiency, or poor quality of planting sets. In contrast, garlic (a) does not typically exhibit this specific named disorder; radish (c) is more prone to disorders like pithiness or hollow heart; and cauliflower (d) is known for disorders like whipping or riceiness. Therefore, buttoning is a characteristic physiological issue in onions.