# Plants, Fungi and Invasive Species for UPSC: Prosopis, Nativity, Legumes, Lichens and the 2024-25 Plant Questions Source: https://tracknation.in/story/plants-fungi-and-invasive-species-for-upsc-prosopis-nativity-legumes-lichens-and-the-2024-25-plant-questions (TrackNation β€” free UPSC notes with PYQs) > Plants in the news for UPSC Prelims: invasive alien species (Prosopis, Lantana, Parthenium, water hyacinth) and KMGBF Target 6, which crops and trees are native to India, nitrogen-fixing legumes and the pea family, lichens, mosses, mycorrhizae and mushrooms, plant chemistry and uses, with the real PYQs from 2018 to 2025. ## How UPSC Tests Plants, Fungi and Invasive Species 🎯 **Exam priority: Tier-2, but the plant questions are about the same dozen ideas, so the return per hour is high.** *Recent papers asked: why Prosopis juliflora* is in the news (2018); the Himalayan nettle (2019); which of fern, lichen, moss and mushroom can survive on a surface without soil (2021); the natural mosquito repellent (2021); palm oil, moringa and tamarind statements (2021); nitrogen-fixing plants (2022); mushrooms with medicinal, psychoactive, insecticidal and bioluminescent properties (2023); which of cashew, papaya and red sanders are native to India (2024); and which of groundnut, horse gram and soybean belong to the pea family (2024); and in 2025 a five-pair description of plants (cassava, ginger, Malabar spinach, mint, papaya). Five ideas cover almost all of it: **invasive aliens**, **nativity** (where a crop or tree came from), **legumes and nitrogen**, **lichens, mosses and fungi**, and **plant chemistry and uses**. This article takes them in that order. ## Invasive Alien Species: Examples, Tracking and the 2030 Target ## Invasive alien species: the highest-yield idea An **alien species** is one introduced, deliberately or by accident, to a region where it does not naturally occur; it becomes **invasive** when it spreads and causes the decline or extinction of native species. NCERT's lists give you the examples you need. | **Invasive species** | **Where and what it does** | **Typical lesson** | | *Prosopis juliflora* (vilayati babul) | A South and Central American tree introduced to India for fuelwood and to restore degraded land; it spreads, crowds out native plants and reduces biodiversity (2018 PYQ) | A species introduced to help can become an invader | | *Parthenium* (carrot grass), *Lantana*, water hyacinth (*Eichhornia*) | NCERT names these as invasive weeds damaging India's native species | Weeds spread fast because they lack their natural enemies | | African catfish (*Clarias gariepinus*) | Illegally introduced for aquaculture; threatens indigenous catfishes in rivers | Aquaculture imports are a major route | | Nile perch in Lake Victoria | Led to the extinction of more than 200 cichlid fish species | The global textbook case | | Prickly pear in Australia (early 1920s) | Overran millions of hectares of rangeland until a cactus-feeding moth was brought in | Biological control works by restoring a predator | Who tracks them? The **Invasive Species Specialist Group**, which develops the Global Invasive Species Database, is part of the IUCN's Species Survival Commission (2023 PYQ). The global framework has a quantified goal: **Target 6 of the Kunming-Montreal Global Biodiversity Framework** asks countries to reduce the introduction and establishment of invasive alien species by **at least 50 per cent by 2030** *(official CBD text)*. Invasives are also one of the four causes of species loss (article 4). ## Where Did It Come From? Nativity and Growth Forms ## Nativity: where did it come from? UPSC's 2024 question asked how many of cashew, papaya and red sanders are native to India. The answer was **only red sanders**. Make a one-line origin note for every plant in the news: | **Plant** | **Native to** | **India link** | | Red sanders (*Pterocarpus santalinus*) | India (Eastern Ghats) | Native and highly valued timber; a protected species and a favourite of the wildlife-trade questions | | Cashew | Northeastern Brazil | Portuguese took it to India in the late sixteenth century; abundant along the coast | | Papaya | Tropical America (south Mexico and Central America) | India is now the world's largest producer | | Oil palm | West Africa (not Southeast Asia, as the 2021 statement claimed) | A raw material for lipstick and perfume, and for biodiesel | | Tamarind | Tropical Africa (not endemic to South Asia) | Collected in India as minor forest produce | | *Prosopis juliflora* | South and Central America | Invasive in dry regions | ### The 2025 'descriptions' question The five plant-description pairs in 2025 were: cassava, a woody shrub (correct); ginger, a herb with pseudostem (correct); Malabar spinach, a herbaceous climber (correct); mint, an annual shrub (wrong: a perennial herb); and papaya, a woody shrub (wrong: a large soft-stemmed herb). Three of five are right. The lesson: **know the growth form of every crop** (shrub, herb, climber, tree). ## Legumes, Lichens, Mosses and Fungi ## Legumes, nitrogen and the pea family Legumes (family Fabaceae, the pea or bean family) carry nitrogen-fixing *Rhizobium* bacteria in root nodules, so they enrich the soil. Use this to settle two PYQs: in 2022 the nitrogen-fixing plants among six were alfalfa, chickpea and clover (not amaranth, purslane or spinach), and in 2024 groundnut, horse gram and soybean all belong to the pea family. Moringa is *not* a legume (2021). Rotation with pulses and green manures is why legumes also feature in the agro-ecology article. ## Lichens, mosses and fungi - **Lichens** are a mutualism of a fungus with a photosynthesising alga or cyanobacterium. With mosses, they survive on bare rock and bark with no soil, which is why they are pioneers of primary succession; ferns (which need moist soil) and mushrooms (which need decaying organic matter) are not. - **Mycorrhizae** are partnerships between fungi and the roots of higher plants: the fungus helps the plant absorb nutrients and the plant provides carbohydrates. - **Mushrooms** (2023): some have medicinal properties (oyster mushrooms), some are psychoactive (psilocybin), some are insecticidal and some are bioluminescent, so all four statements were true. - **Extremophile microbes** (2023): some grow above the boiling point of water at deep-sea vents, some below freezing in brine, and some at a pH below 3. ## Plant Chemistry, Uses, Botanical Discoveries and How UPSC Could Ask Next ## Plant chemistry and uses - **Chemical defences become commercial products.** NCERT notes that nicotine, caffeine, quinine, strychnine and opium are plant chemicals that evolved as defences against grazers; *Calotropis* (madar) carries cardiac glycosides, which is why cattle avoid it. *Cuscuta* (dodder) is a parasitic plant that has lost its chlorophyll and leaves. - **Himalayan nettle** (*Girardinia diversifolia*) yields a textile fibre and supports livelihoods in remote hill villages (2019). - **Lemongrass** is the source of citronella, the natural mosquito repellent (2021). - **Minor forest produce**: bamboo, tamarind, tendu leaves and honey are minor forest produce under the Forest Rights Act; the community has rights to collect, use and sell them (see the forests article). ### Current news: botanical discoveries (2025) The Botanical Survey of India published **'Plant Discoveries 2024'**; a national institute reported two orchid species new to science (*Phalaenopsis quadridentata* and *Gastrodia indica*); and the Zoological Survey of India reported 117 new animal species discovered in the year. Discoveries of this kind are the usual 'in news' hook for questions on taxonomy and bio-resources. ## How UPSC Could Ask This Next - **'Why is plant X in the news?'** (invasive tree, rare orchid, fibre plant, new variety). - **Origin and nativity:** 'how many of the following are native to India'. - **Biological facts in statement form:** nitrogen fixation, parasitic plants, symbioses, growth forms. - **Invasives and policy:** KMGBF Target 6, the IUCN Invasive Species Specialist Group, biological control. ## Further Reading - NCERT Biology (Class 12) and Geography textbooks, the India State of Forest Report, the MoEFCC Annual Report, the Economic Survey and the official lists cited in this note β€” the primary sources behind every figure above. ## Test Yourself: Practice Questions and PYQs Twelve practice questions on invasive species, plant origins, legumes, lichens and fungi, followed by the real UPSC Prelims questions on plants in the news. ## Practice Questions **Q1.** Consider the following statements about invasive alien species: 1. They are species introduced to a region where they do not naturally occur and that spread and harm native species. 2. Parthenium, Lantana and water hyacinth are named by NCERT as invasive weeds in India. 3. Prosopis juliflora was introduced to India for fuelwood and land restoration and is now invasive. Which of the statements given above are correct? - (a) 1 and 3 only - (b) 1 and 2 only - (c) 1, 2 and 3 - (d) 2 and 3 only **Answer: (c)** β€” All three are correct. **Q2.** Target 6 of the Kunming-Montreal Global Biodiversity Framework seeks to - (a) protect 50 per cent of land by 2030 - (b) halve plastic use by 2030 - (c) eliminate all alien species by 2030 - (d) reduce the introduction and establishment of invasive alien species by at least 50 per cent by 2030 **Answer: (d)** β€” The target is a 50 per cent cut in the rates of introduction and establishment of invasive species by 2030. Target 3 is the 30 per cent protection goal. **Q3.** Which one of the following is the Global Invasive Species Database associated with? - (a) The CITES Secretariat - (b) The Ramsar Convention - (c) The World Wide Fund for Nature - (d) The Invasive Species Specialist Group of the IUCN **Answer: (d)** β€” The Invasive Species Specialist Group is part of the IUCN's Species Survival Commission. **Q4.** The 2018 UPSC question asked why Prosopis juliflora is mentioned in the news. The correct reason is that it - (a) tends to reduce the biodiversity of the area in which it grows - (b) is used in the synthesis of pesticides - (c) yields an extract widely used in cosmetics - (d) is the main source of a rare timber **Answer: (a)** β€” Prosopis juliflora is an invasive South American tree that crowds out native plants. **Q5.** Consider the following plants: 1. Cashew 2. Papaya 3. Red sanders How many of the above trees are native to India? - (a) Only two - (b) Only one - (c) None - (d) All three **Answer: (b)** β€” Only red sanders (Eastern Ghats) is native; cashew is from Brazil and papaya from tropical America. **Q6.** Which of the following are nitrogen-fixing plants? 1. Alfalfa 2. Amaranth 3. Chickpea 4. Clover 5. Spinach - (a) 1, 2, 3, 4 and 5 - (b) 2, 4 and 5 only - (c) 1, 2 and 5 only - (d) 1, 3 and 4 only **Answer: (d)** β€” Alfalfa, chickpea and clover are legumes with nitrogen-fixing root nodules; amaranth and spinach are not. **Q7.** Consider the following plants: 1. Groundnut 2. Horse gram 3. Soybean How many of the above belong to the pea family? - (a) None - (b) All three - (c) Only two - (d) Only one **Answer: (b)** β€” All three are legumes of the family Fabaceae. **Q8.** Which of the following is/are most likely to be found surviving on a surface without soil? 1. Fern 2. Lichen 3. Moss 4. Mushroom - (a) 2 and 3 - (b) 1, 3 and 4 - (c) 2 only - (d) 1 and 4 **Answer: (a)** β€” Lichens and mosses colonise bare rock or bark; ferns need moist soil and mushrooms need decaying organic matter. **Q9.** Consider the following statements about the oil palm and tamarind: 1. The oil palm is native to West Africa. 2. Tamarind is endemic to South Asia. 3. In India, tamarind is collected mostly as minor forest produce. Which of the statements given above are correct? - (a) 1 and 2 only - (b) 1, 2 and 3 - (c) 1 and 3 only - (d) 2 and 3 only **Answer: (c)** β€” Tamarind is native to tropical Africa, so 2 is wrong. **Q10.** Which of the following is a parasitic plant that has lost its chlorophyll and leaves? - (a) Lantana - (b) Cuscuta - (c) Calotropis - (d) Opuntia **Answer: (b)** β€” Cuscuta (dodder) draws nutrition from its host plant. Calotropis and Lantana are free-living plants and Opuntia is a cactus. **Q11.** Statement-I: Lichens are pioneers in the primary succession on bare rock. Statement-II: A lichen is a mutualistic association between a fungus and a photosynthetic alga or cyanobacterium. Which one of the following is correct in respect of the above statements? - (a) Both statements are correct but Statement-II does not explain Statement-I - (b) Both statements are correct and Statement-II explains Statement-I - (c) Statement-I is incorrect but Statement-II is correct - (d) Statement-I is correct but Statement-II is incorrect **Answer: (b)** β€” The alga or cyanobacterium photosynthesises and the fungus holds on and absorbs water and minerals, so the partnership can live on bare rock where soil is absent. **Q12.** Which one of the following is the source of the natural mosquito repellent citronella? - (a) Nut grass - (b) Congress grass - (c) Elephant grass - (d) Lemongrass **Answer: (d)** β€” Citronella oil is obtained from lemongrass; Congress grass is an invasive weed and nut grass a sedge. ### UPSC Previous Year Questions (PYQs) *Real UPSC Prelims questions, checked against the official paper and answer key.* **Q1.** (2018) Why is a plant called Prosopis Juliflora often mentioned in the news? - (a) It tends to reduce the biodiversity in the area in which it grows. - (b) None of these - (c) Its extract is widely used in cosmetics. - (d) Its extract is used in the synthesis of pesticides. **Answer: (a)** β€” Prosopis juliflora (vilayati babul) is an invasive South American tree that crowds out native plants and reduces biodiversity where it spreads, which is why it keeps appearing in the news. **Q2.** (2019) Recently, there was a growing awareness in our country about the importance of Himalayan nettle (Girardinia diversifolia) because it is found to be a sustainable source of - (a) pulp for paper industry - (b) biodiesel - (c) anti-malarial drug - (d) textile fibre **Answer: (d)** β€” Himalayan nettle (Girardinia diversifolia) yields a fibre that is woven into cloth, a livelihood for hill communities. **Q3.** (2021) In the nature, which of the following is/are most likely to be found surviving on a surface without soil? 1. Fern 2. Lichen 3. Moss 4. Mushroom Select the correct answer using the code given below. - (a) 2 and 3 - (b) 1, 3 and 4 - (c) 2 only - (d) 1 and 4 only **Answer: (a)** β€” Lichens and mosses can live on bare rock or bark without soil. Ferns need moist soil with organic matter and mushrooms need a decaying organic substrate, so only 2 and 3. **Q4.** (2021) Which one of the following is used in preparing a natural mosquito repellent? - (a) Nut grass - (b) Lemongrass - (c) Elephant grass - (d) Congress grass **Answer: (b)** β€” Lemongrass is the source of citronella oil, the natural mosquito repellent. Congress grass is an invasive weed, elephant grass is a fodder and nut grass is a sedge. **Q5.** (2021) With reference to 'palm oil', consider the following statements: 1. The palm oil tree is native to Southeast Asia. 2. The palm oil is a raw material for some industries producing lipstick and perfumes. 3. The palm oil can be used to produce biodiesel. Which of the statements given above are correct? - (a) 2 and 3 only - (b) 1 and 3 only - (c) 1 and 2 only - (d) 1, 2 and 3 **Answer: (a)** β€” The oil palm is native to West Africa, not Southeast Asia, so 1 is wrong. Palm oil is used in cosmetics and perfumes and can be turned into biodiesel, so 2 and 3 are right. **Q6.** (2021) Consider the following statements: 1. Moringa (drumstick tree) is a leguminous evergreen tree. 2. Tamarind tree is endemic to South Asia. 3. In India, most of the tamarind is collected as minor forest produce. 4. India exports tamarind and seeds of moringa. 5. Seeds of moringa and tamarind can be used in the production of biofuels. Which of the statements given above are correct? - (a) 1, 2, 3 and 5 - (b) 1, 3 and 4 - (c) 1, 2, 4 and 5 - (d) 3, 4 and 5 **Answer: (d)** β€” Moringa is not a legume (it belongs to Moringaceae) and tamarind is native to tropical Africa, so 1 and 2 are wrong. Tamarind is gathered as minor forest produce, India exports tamarind and moringa seed, and both seeds can yield biofuel. **Q7.** (2022) Which of the following are nitrogen-fixing plants? 1. Alfalfa 2. Amarnath 3. Chickpea 4. Clover 5. Purslane (Kulfa) 6. Spinach Select the correct answer using the code given below: - (a) 1, 2, 4, 5 and 6 - (b) 1, 3, 5 and 6 only - (c) 2, 4, 5 and 6 only - (d) 1, 3 and 4 only **Answer: (d)** β€” Nitrogen-fixing plants are legumes: alfalfa, chickpea and clover. Amaranth, purslane (kulfa) and spinach are not legumes. **Q8.** (2023) Consider the following statements: 1. Some mushrooms have medicinal properties. 2. Some mushrooms have psychoactive properties. 3. Some mushrooms have insecticidal properties. 4. Some mushrooms have bioluminescent properties. How many of the above statements are correct? - (a) All four - (b) Only three - (c) Only one - (d) Only two **Answer: (a)** β€” Mushrooms include medicinal species (such as oyster mushrooms), psychoactive ones (psilocybin), insecticidal ones and bioluminescent ones, so all four statements hold. **Q9.** (2024) Consider the following : 1. Cashew 2. Papaya 3. Red sanders How many of the above trees are actually native to India ? - (a) None - (b) All three - (c) Only two - (d) Only one **Answer: (d)** β€” Only red sanders (Pterocarpus santalinus) is native to India, found in the Eastern Ghats. Cashew came from Brazil and papaya from Central America. **Q10.** (2024) Consider the following plants : 1. Groundnut 2. Horse-gram 3. Soybean How many of the above belong to the pea family ? - (a) Only one - (b) All three - (c) None - (d) Only two **Answer: (b)** β€” Groundnut, horse gram and soybean are all legumes of the pea family (Fabaceae). **Q11.** (2025) Consider the following pairs : Plant : Description I. Cassava : Woody shrub II. Ginger : Herb with pseudostem III. Malabar spinach : Herbaceous climber IV. Mint : Annual shrub V. Papaya : Woody shrub How many of the above pairs are correctly matched? - (a) Only two - (b) Only four - (c) All the five - (d) Only three **Answer: (d)** β€” Cassava is a woody shrub, ginger a herb with a pseudostem and Malabar spinach a herbaceous climber. Mint is a perennial herb and papaya is a large soft-stemmed herb, so those two pairs are wrong and three are correct. ### Mains Practice Questions Use these to frame full-length answers. You don't have to answer one exactly β€” they show the angles UPSC tests, so let them guide which points you cover. - What are invasive alien species? Discuss their impact on India's biodiversity with examples and suggest management strategies. - Biological control of invasive species is promising but carries risks. Discuss with examples. - Explain the role of legumes and nitrogen-fixing microbes in sustainable agriculture. - Why are lichens and mosses called pioneer species? Explain their role in ecological succession. - How does India's biodiversity legislation deal with the access to and sharing of benefits from plant genetic resources? ### UPSC Mains β€” Previous Years’ Questions on this topic (last 10 years) No direct GS Mains question has been asked specifically on this topic in the last decade β€” it is primarily a **Prelims** area. Use the practice prompts above to stay exam-ready.