Here is the official UPSC Botany Optional syllabus for Paper I and Paper II, arranged paper by paper and unit by unit. Under each unit we give the official text first, then break it into numbered topics, so you can track your preparation and match every previous year question to its topic.
Source. UPSC Civil Services Examination 2026 notification (Examination Notice No. 05/2026-CSE, dated 04.02.2026, pp. 48–50), upsc.gov.in. The Botany syllabus has been unchanged in recent years.
Scheme. Two papers of 250 marks each (total 500), 3 hours each. Each paper has two sections (A and B) of four questions each; Questions 1 and 5 are compulsory, and three more are attempted with at least one from each section. The syllabus itself is not divided into sections. Paper I has five units (Microbiology and Plant Pathology; Cryptogams; Phanerogams; Plant Resource Development; Morphogenesis); Paper II has five (Cell Biology; Genetics, Molecular Biology and Evolution; Plant Breeding, Biotechnology and Biostatistics; Physiology and Biochemistry; Ecology and Plant Geography).
Syllabus at a glance
| Paper | Unit | Topics |
|---|---|---|
| Paper I | 1. Microbiology and Plant Pathology | 5 |
| Paper I | 2. Cryptogams | 5 |
| Paper I | 3. Phanerogams | 8 |
| Paper I | 4. Plant Resource Development | 3 |
| Paper I | 5. Morphogenesis | 3 |
| Paper II | 1. Cell Biology | 7 |
| Paper II | 2. Genetics, Molecular Biology and Evolution | 9 |
| Paper II | 3. Plant Breeding, Biotechnology and Biostatistics | 5 |
| Paper II | 4. Physiology and Biochemistry | 10 |
| Paper II | 5. Ecology and Plant Geography | 8 |
Paper I
1. Microbiology and Plant Pathology
Official syllabus text
Structure and reproduction/multiplication of viruses, viroids, bacteria, fungi and mycoplasma; Applications of microbiology in agriculture, industry, medicine and in control of soil and water pollution; Prion and Prion hypothesis.
Important crop diseases caused by viruses, bacteria, mycoplasma, fungi and nematodes; Modes of infection and dissemination; Molecular basis of infection and disease resistance/defence; Physiology of parasitism and control measures. Fungal toxins. Modelling and disease forecasting; Plant quarantine.
1.1 Viruses, viroids and prions
- Structure and multiplication of viruses and viroids
- Prion and prion hypothesis
1.2 Bacteria, mycoplasma and fungi
- Structure and reproduction of bacteria, fungi and mycoplasma
1.3 Applied microbiology
- Microbiology in agriculture, industry and medicine
- Control of soil and water pollution
1.4 Crop diseases
- Diseases caused by viruses, bacteria, mycoplasma, fungi and nematodes
- Modes of infection and dissemination
1.5 Host–pathogen interaction and disease control
- Molecular basis of infection and disease resistance
- Physiology of parasitism
- Control measures
- Fungal toxins
- Disease forecasting
- Plant quarantine
2. Cryptogams
Official syllabus text
Algae, fungi, lichens, bryophytes, pteridophytes—structure and reproduction from evolutionary viewpoint; Distribution of Cryptogams in India and their ecological and economic importance.
2.1 Algae
2.2 Fungi and lichens
- Fungi
- Lichens
2.3 Bryophytes
2.4 Pteridophytes
2.5 Cryptogams in India
- Distribution
- Ecological and economic importance
3. Phanerogams
Official syllabus text
Gymnosperms: Concept of Progymnosperms. Classification and distribution of gymnosperms. Salient features of Cycadales, Ginkgoales, Coniferales and Gnetales, their structure and reproduction. General account of Cycadofilicales, Bennettitales and Cordaitales; Geological time scale; Type of fossils and their study techniques.
Angiosperms: Systematics, anatomy, embryology, palynology and phylogeny.
Taxonomic hierarchy; International Code of Botanical Nomenclature; Numerical taxonomy and chemotaxonomy; Evidence from anatomy, embryology and palynology.
Origin and evolution of angiosperms; Comparative account of various systems of classification of angiosperms; Study of angiospermic families—Magnoliaceae, Ranunculaceae, Brassicaceae, Rosaceae, Fabaceae, Euphorbiaceae, Malvaceae, Dipterocarpaceae, Apiaceae, Asclepiadaceae, Verbenaceae, Solanaceae, Rubiaceae, Cucurbitaceae, Asteraceae, Poaceae, Arecaceae, Liliaceae, Musaceae and Orchidaceae.
Stomata and their types; Glandular and non-glandular trichomes; Unusual secondary growth; Anatomy of C3 and C4 plants; Xylem and phloem differentiation; Wood anatomy.
Development of male and female gametophytes, pollination, fertilization; Endosperm—its development and function. Patterns of embryo development; Polyembryony, apomixis; Applications of palynology; Experimental embryology including pollen storage and test-tube fertilization.
3.1 Gymnosperms
- Progymnosperms
- Classification and distribution
- Cycadales, Ginkgoales, Coniferales and Gnetales
3.2 Fossil plants and palaeobotany
- Cycadofilicales, Bennettitales and Cordaitales
- Geological time scale
- Types of fossils and study techniques
3.3 Taxonomy and nomenclature
- Taxonomic hierarchy
- ICBN
- Numerical taxonomy and chemotaxonomy
- Evidence from anatomy, embryology and palynology
3.4 Origin of angiosperms and systems of classification
- Origin and evolution of angiosperms
- Systems of classification
3.5 Angiosperm families
- Magnoliaceae, Ranunculaceae, Brassicaceae, Rosaceae, Fabaceae, Euphorbiaceae, Malvaceae, Dipterocarpaceae, Apiaceae, Asclepiadaceae
- Verbenaceae, Solanaceae, Rubiaceae, Cucurbitaceae, Asteraceae, Poaceae, Arecaceae, Liliaceae, Musaceae, Orchidaceae
3.6 Plant anatomy
- Stomata
- Trichomes
- Unusual secondary growth
- Anatomy of C3 and C4 plants
- Xylem and phloem differentiation
- Wood anatomy
3.7 Embryology
- Male and female gametophytes
- Pollination and fertilization
- Endosperm
- Embryo development
- Polyembryony and apomixis
3.8 Palynology and experimental embryology
- Applications of palynology
- Pollen storage
- Test-tube fertilization
4. Plant Resource Development
Official syllabus text
Domestication and introduction of plants; Origin of cultivated plants, Vavilov’s centres of origin.
Plants as sources for food, fodder, fibres, spices, beverages, edible oils, drugs, narcotics, insecticides, timber, gums, resins and dyes; latex, cellulose, starch and its products; Perfumery; Importance of Ethnobotany in Indian context; Energy plantations; Botanical Gardens and Herbaria.
4.1 Domestication and origin of cultivated plants
- Domestication and introduction
- Vavilov’s centres of origin
4.2 Economic botany
- Food, fodder, fibres, spices, beverages, edible oils
- Drugs, narcotics, insecticides
- Timber, gums, resins, dyes, latex
- Cellulose, starch
- Perfumery
4.3 Ethnobotany, energy plantations, gardens and herbaria
- Ethnobotany in Indian context
- Energy plantations
- Botanical gardens and herbaria
5. Morphogenesis
Official syllabus text
Totipotency, polarity, symmetry and differentiation; Cell, tissue, organ and protoplast culture.
Somatic hybrids and Cybrids; Micropropagation; Somaclonal variation and its applications; Pollen haploids, embryo rescue methods and their applications.
5.1 Totipotency and differentiation
- Totipotency, polarity, symmetry and differentiation
5.2 Plant tissue culture
- Cell, tissue, organ and protoplast culture
- Micropropagation
- Somaclonal variation
5.3 Somatic hybrids, haploids and embryo rescue
- Somatic hybrids and cybrids
- Pollen haploids
- Embryo rescue
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1. Cell Biology
Official syllabus text
Techniques of cell biology. Prokaryotic and eukaryotic cells—structural and ultrastructural details; Structure and function of extracellular matrix (cell wall) and membranes—cell adhesion, membrane transport and vesicular transport; Structure and function of cell organelles (chloroplasts, mitochondria, ER, dictyosomes, ribosomes, endosomes, lysosomes, peroxisomes); Cytoskeleton and microtubules; Nucleus, nucleolus, nuclear pore complex; Chromatin and nucleosome; Cell signalling and cell receptors; Signal transduction; Mitosis and meiosis; molecular basis of cell cycle. Numerical and structural variations in chromosomes and their significance; Chromatin organization and packaging of genome; Polytene chromosomes; B-chromosomes—structure, behaviour and significance.
1.1 Cell biology techniques and cell structure
- Techniques of cell biology
- Prokaryotic and eukaryotic cells
1.2 Cell wall and membranes
- Extracellular matrix
- Cell adhesion
- Membrane and vesicular transport
1.3 Cell organelles and cytoskeleton
- Chloroplasts, mitochondria, ER, dictyosomes, ribosomes, endosomes, lysosomes, peroxisomes
- Cytoskeleton and microtubules
1.4 Nucleus and chromatin
- Nucleus, nucleolus, nuclear pore complex
- Chromatin and nucleosome
- Packaging of genome
1.5 Cell signalling
- Cell receptors
- Signal transduction
1.6 Cell division and cell cycle
- Mitosis and meiosis
- Molecular basis of cell cycle
1.7 Chromosome variation and special chromosomes
- Numerical and structural variations
- Polytene chromosomes
- B-chromosomes
2. Genetics, Molecular Biology and Evolution
Official syllabus text
Development of genetics, and gene versus allele concepts (Pseudoalleles); Quantitative genetics and multiple factors; Incomplete dominance, polygenic inheritance, multiple alleles; Linkage and crossing over of gene mapping including molecular maps (idea of mapping, function); Sex chromosomes and sex-linked inheritance; sex determination and molecular basis of sex differentiation; Mutations (biochemical and molecular basis); Cytoplasmic inheritance and cytoplasmic genes (including genetics of male sterility).
Structure and synthesis of nucleic acids and proteins; Genetic code and regulation of gene expression; Gene silencing; Multigene families; Organic evolution—evidences, mechanism and theories.
Role of RNA in origin and evolution.
2.1 Mendelian genetics and gene interactions
- Development of genetics
- Gene and allele concepts, pseudoalleles
- Incomplete dominance
- Multiple alleles
2.2 Quantitative genetics
- Multiple factors
- Polygenic inheritance
2.3 Linkage and gene mapping
- Linkage and crossing over
- Gene mapping
- Molecular maps
2.4 Sex determination and sex-linked inheritance
- Sex chromosomes
- Sex-linked inheritance
- Sex determination and differentiation
2.5 Mutations
2.6 Cytoplasmic inheritance
- Cytoplasmic genes
- Genetics of male sterility
2.7 Nucleic acids and protein synthesis
- Structure and synthesis of nucleic acids and proteins
- Genetic code
2.8 Gene regulation
- Regulation of gene expression
- Gene silencing
- Multigene families
2.9 Evolution
- Organic evolution: evidences, mechanism and theories
- Role of RNA in origin and evolution
3. Plant Breeding, Biotechnology and Biostatistics
Official syllabus text
Methods of plant breeding—introduction, selection and hybridization (pedigree, backcross, mass selection, bulk method); Mutation, polyploidy, male sterility and heterosis breeding. Use of apomixis in plant breeding; DNA sequencing; Genetic engineering—methods of transfer of genes; Transgenic crops and biosafety aspects; Development and use of molecular markers in plant breeding; Tools and techniques—probe, southern blotting, DNA fingerprinting, PCR and FISH. Standard deviation and coefficient of variation (CV). Tests of significance (Z-test, t-test and chi-square tests). Probability and distributions (normal, binomial and Poisson). Correlation and regression.
3.1 Methods of plant breeding
- Introduction, selection and hybridization
- Pedigree, backcross, mass selection, bulk method
3.2 Mutation, polyploidy and heterosis breeding
- Mutation breeding
- Polyploidy
- Male sterility
- Heterosis
- Apomixis in breeding
3.3 Genetic engineering and transgenic crops
- DNA sequencing
- Methods of gene transfer
- Transgenic crops
- Biosafety
3.4 Molecular markers and techniques
- Molecular markers in breeding
- Probe, Southern blotting, DNA fingerprinting, PCR, FISH
3.5 Biostatistics
- Standard deviation and CV
- Z-test, t-test and chi-square
- Probability and distributions
- Correlation and regression
4. Physiology and Biochemistry
Official syllabus text
Water relations, mineral nutrition and ion transport, mineral deficiencies. Photosynthesis—photochemical reactions, photophosphorylation and carbon fixation pathways; C3, C4 and CAM pathways; Mechanism of phloem transport, Respiration (anaerobic and aerobic, including fermentation)—electron transport chain and oxidative phosphorylation; Photorespiration; Chemiosmotic theory and ATP synthesis; Lipid metabolism; Nitrogen fixation and nitrogen metabolism. Enzymes, coenzymes; Energy transfer and energy conservation. Importance of secondary metabolites. Pigments as photoreceptors (plastidial pigments and phytochrome). Plant movements; Photoperiodism and flowering, vernalization, senescence; Growth substances—their chemical nature, role and applications in agri-horticulture; growth indices, growth movements. Stress physiology (heat, water, salinity, metal); Fruit and seed physiology. Dormancy, storage and germination of seed. Fruit ripening—its molecular basis and manipulation.
4.1 Water relations and mineral nutrition
- Water relations
- Mineral nutrition and ion transport
- Mineral deficiencies
4.2 Photosynthesis
- Photochemical reactions
- Photophosphorylation
- C3, C4 and CAM pathways
- Photorespiration
4.3 Phloem transport
4.4 Respiration and bioenergetics
- Anaerobic and aerobic respiration, fermentation
- ETC and oxidative phosphorylation
- Chemiosmotic theory and ATP synthesis
- Energy transfer
4.5 Lipid and nitrogen metabolism
- Lipid metabolism
- Nitrogen fixation and nitrogen metabolism
4.6 Enzymes and secondary metabolites
- Enzymes and coenzymes
- Secondary metabolites
4.7 Photoreceptors, photoperiodism and plant movements
- Plastidial pigments and phytochrome
- Photoperiodism and flowering
- Vernalization
- Plant movements
4.8 Growth substances and senescence
- Plant growth regulators
- Growth indices
- Senescence
4.9 Stress physiology
- Heat, water, salinity and metal stress
4.10 Seed and fruit physiology
- Dormancy, storage and germination of seed
- Fruit ripening
5. Ecology and Plant Geography
Official syllabus text
Concept of ecosystem; Ecological factors. Concepts and dynamics of community; Plant succession. Concepts of biosphere; Ecosystems; Conservation; Pollution and its control (including phytoremediation); Plant indicators; Environment (Protection) Act.
Forest types of India—Ecological and economic importance of forests, afforestation, deforestation and social forestry; Endangered plants, endemism, IUCN categories, Red Data Books; Biodiversity and its conservation; Protected Area Network; Convention of Biological Diversity, Farmers’ Rights; and Intellectual Property Rights; Concept of Sustainable Development; Biogeochemical cycles. Global warming and climatic change; Invasive species; Environmental Impact Assessment; Phytogeographical regions of India.
5.1 Ecosystem and community ecology
- Concept of ecosystem
- Ecological factors
- Community dynamics
- Plant succession
- Biosphere
5.2 Biogeochemical cycles
5.3 Pollution and environmental management
- Pollution and its control
- Phytoremediation
- Plant indicators
- Environment (Protection) Act
- EIA
5.4 Forests of India
- Forest types
- Importance of forests
- Afforestation, deforestation, social forestry
5.5 Biodiversity and conservation
- Endangered plants, endemism, IUCN categories, Red Data Books
- Biodiversity conservation
- Protected Area Network
5.6 CBD, farmers’ rights and IPR
- Convention on Biological Diversity
- Farmers’ rights
- Intellectual Property Rights
5.7 Global change and sustainable development
- Global warming and climate change
- Invasive species
- Sustainable development
5.8 Phytogeographical regions of India
Total: 63 numbered topics across 10 units.
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