🍚Rice -- India's Lifeline Crop (Complete Production Guide)

In the waterlogged paddies of West Bengal and the terraced fields of Manipur, rice shapes the livelihood of millions. It occupies nearly a quarter of India’s cropped area and supplies 43% of total food grain production. Whether you are preparing for AFO, NABARD, or IBPS SO, rice is the single most examined crop.

In the previous lesson, we established the classification framework for all crops — seasonal, botanical, and special-purpose groupings. Now we apply that framework to rice, the most important individual crop in India.

This chapter covers:

1. Basics and global standing — botany, protein, area, production, and productivity rankings
2. Climate and cultivation — seasons, nursery methods, transplanting, SRI
3. Nutrient and water management — NPK doses, nitrogen management, water use efficiency
4. Varieties — historical development from TN-1 to Swarna Sub 1, basmati, and hybrid rice
5. Golden rice and biofortification — Vitamin A enrichment
6. Pests and diseases — Khaira, BLB, Tungro, and more

All sections are high-yield for IBPS AFO, NABARD, and RRB SO exams.

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Basics

• Botanical name: Oryza sativa ^{AFO 2021}
• Family: Poaceae (Gramineae)
• Origin: South-East Asia
• Chromosome: 2n = 24 (diploid)
• Rice is the most important crop of India, occupying 23.3 per cent of the gross cropped area.
• It contributes 43 per cent of total food grain production and 46 per cent of total cereal production.
• Only 10% of rice is grown outside Asia — it is predominantly an Asian crop.
• Rice contains about 70 per cent carbohydrate, 6-7 per cent protein (Oryzein), and 2.5% fat.
• Rice protein is rich in lysine (4%), an essential amino acid typically deficient in most other cereals, making rice protein nutritionally superior.
• Oryza has 24 species, of which only Oryza sativa (grown in India) and Oryza glaberrima (grown in Africa) are cultivated; the remaining 22 are wild types.
• O. sativa is believed to have evolved from O. nivara.

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Rice Growing Regions in India

India’s diverse agro-climatic zones allow rice to be cultivated across almost every region.

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Global and National Standing

World

• India exported 15.5 million metric tonnes of rice in 2020-21 (highest in the world).
• India’s major basmati export destination: Iran > Saudi Arabia > UAE.
• India’s major non-basmati export destination: Nepal > Benin > Senegal.
• Import of seeds is restricted; import for human consumption is permitted through State Trading Enterprises.

India

• Rice is the largest staple food crop of India.
• Production: West Bengal > UP > Andhra Pradesh. Total: 122.27 MT (2020-21).
• Area: Uttar Pradesh (highest).
• Highest Productivity: Punjab (55-60 q/ha). National average: 20 q/ha.
• Punjab achieves high productivity through assured irrigation, high-yielding varieties, and intensive management.

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Climate Requirements

Rice demands warm, humid conditions with abundant water throughout the growing season. Understanding these requirements explains why rice dominates eastern and southern India but plays a secondary role in the arid north-west.

• Rice is grown in three seasons in Eastern and Peninsular India because of temperature uniformity.
• Acidic soils favour availability of iron and other micronutrients.

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Seasons of Rice Cultivation

Rice is grown in three seasons in Eastern and Peninsular India because temperature remains suitable year-round:

Oryza sativa has three subspecies/varietal groups: Indica (tropical, long-grain, grown in lowland India), Japonica (temperate, short-grain, grown in Japan and Korea), and Javanica (intermediate, grown in Indonesia). Most Indian rice belongs to the Indica group.

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Morphology

Rice has distinctive floral and structural features that set it apart from other cereals and are frequently tested in exams.

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Varieties — Historical Development

Understanding the lineage of Indian rice varieties is a favourite exam topic. Here is the logical sequence:

1. TN-1 (Taichung Native-1): Developed in Taiwan after World War II — one of the earliest semi-dwarf, fertiliser-responsive varieties.
   • TN-1 = Dee-geo-woo-gen (dwarf, N-responsive) x Tsai Yung Chung (tall, drought resistant)
   • Introduced to India in 1964-65 by G. V. Chalam (2 kg from IRRI). Before TN-1, rice productivity was about 2 q/ha; after, it reached 8 q/ha — marking the start of the Green Revolution in Indian rice.

2. IR-8: Evolved by breeder Henry Beachell at IRRI, Manila. Called “Miracle Rice” globally for unprecedented yields.
   • IR-8 = Dee-geo-woo-gen (China) x Peta (Indonesia)
   • Introduced to India in 1966 and out-yielded TN-1.

3. Jaya: First rice variety developed under India’s own programme by Dr. Shastry.
   • Jaya = TN-1 (Taiwan) x T-141 (Indian). Out-yielded both TN-1 and IR-8 — called Miracle Rice of India.

4. Padma: Reverse cross of Jaya’s parents — Padma = T-141 x TN-1.
5. Jagannath: Mutant variety of T-141.
6. Sahbhagi Dhan: Drought-tolerant variety for rainfed areas.

7. Swarna-Sub 1: Submergence-tolerant — survives 14 days under water. Invaluable for flood-prone eastern India.

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Basmati Rice

• Basmati 370, Basmati 385, 1121 (Extra-long grain variety).
• Pusa Basmati-1 (Muchal): World’s first high-yielding dwarf variety under quality rice, developed by IARI through convergent breeding.

• Fragrant varieties derived from basmati stock but not true basmati: PB-2 (Sugandha-2), PB-3, RS-10.
• A basmati grain contains 0.09 ppm of aromatic chemical — 12 times more than non-basmati rice.
• The characteristic fragrance is caused by 2-acetyl-1-pyrroline (pandan-like aroma).

Non-Basmati Rice

Gobindbhog: Cultivated mostly in West Bengal; awarded G.I. tag for its white, aromatic, sticky rice with a sweet buttery flavour. Named after offerings to Govindaji, the family deity of the Setts of Kolkata.

Rice Varieties for Special Conditions

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Types of Rice Cultivation

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Methods of Rice Cultivation

1. Dry or Semi-dry Upland Cultivation

• Broadcasting the seed, or sowing behind the plough / drilling.

2. Wet or Lowland Cultivation

• The major part of India’s rice is grown under lowland conditions.
• Optimum depth of puddling: 5 cm (creates an impervious layer reducing water percolation loss).
• Transplanting in puddled fields, or broadcasting sprouted seeds in puddled fields.

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Types of Nursery in Rice

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Dapog Method

• Originated in the Philippines.
• Seedlings ready for transplanting on the 12th day — the fastest nursery method available.
• Seed rate: sprouted seeds @ 1.5-2 kg/m2 (2.5 times higher than other methods) on wooden planks, trays, or concrete floor covered with polythene.
• Seedlings from 1 m2 are sufficient for 200-250 m2 of field.
• Crop flowers days earlier when transplanted by this method.

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Transplanting

• Ideal age: Seedling with 4 leaves (not 5). Age: 20-30 days in Kharif (spacing 20 x 15 cm), 30-35 days in Rabi (spacing 15 x 15 cm).
• Thumb rule: Age of transplanting = 1/4th of total crop duration.

Spacing

• Paira and Utera cropping systems are most practised in Odisha, Bihar, and Chhattisgarh.
• The most prominent cropping pattern of rice in India is Rice-Wheat, feeding the majority of the population.

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Nutrient Management

Rice nutrient management is dominated by nitrogen because waterlogged conditions create a unique soil chemistry — ammoniacal nitrogen is stable while nitrate nitrogen is rapidly lost through denitrification. Understanding this distinction is the key to efficient fertilisation.

• Ammonium polyphosphate is superior to both DAP and SSP, especially in acid clay loams.

• N loss can be reduced by placing ammoniacal fertiliser in the reduced zone and nitrate fertiliser in the oxidised zone. In lowland rice, fertiliser is applied in the reduced zone only.

• Zinc deficiency is a major problem in intensively cultivated and saline-sodic soils. Apply ZnSO4 @ 40 kg/ha every three crop seasons (100 kg/ha initially in saline-sodic soils).

• Gypsum @ 6 t/ha for sodic soils (pH 9.5-9.7) rapidly reduces exchangeable sodium from 70% to 50% in the first season. A combination of gypsum (3 t/ha) + green manure (6 t/ha) is equally effective.

• Iron toxicity in acid Ultisols, Oxisols, and acid-sulphate soils — varietal tolerance is the only solution. Phalguna shows some tolerance.

• Rice paddies emit CH4 (methane), a potent greenhouse gas.

Nitrogen Management in Rice

• Azolla: A free-floating fern hosting the nitrogen-fixing cyanobacterium Anabaena azollae, applied for N fixation and organic matter enrichment.
• Azospirillum: Nitrogen-fixing bacterium found on the root surface of rice — a low-cost biological alternative for partial N supplementation.

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Water Management

Rice is the most water-intensive cereal — it requires continuous submergence during much of its growth. This makes water management the single largest determinant of rice production costs and environmental impact.

• Rice has the lowest water use efficiency (WUE) and is the highest water-consuming crop.
• 5 critical growth stages for irrigation: Seedling, Tillering, Panicle Initiation (most critical), Flowering, Dough/Maturity.
• The critical stages for both fertiliser and irrigation are Tillering and Panicle Initiation (PI).

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Seed Rate

• Germination: Hypogeal — cotyledons remain below the soil surface.
• Test weight (1000 grains): 25 g

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Weed Control

• Most dominant weed: Echinochloa spp. (Wild Rice) — closely resembles rice in early stages, making identification difficult.

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Harvesting and Post-Harvest

• Rice cleaned = 2/3 of paddy weight.
• Rice husk contains 15-18% silica — used in silicate and glass manufacture.

Parboiled Rice

• Retains more B-complex vitamins (especially Thiamine / B1) that are otherwise lost during milling and polishing.
• Parboiling involves partial boiling of paddy with husk to increase nutritional value, change texture, and reduce milling breakage. Three steps: Soaking, Steaming, Drying.

• Dehusked rice = Brown rice (retains the bran layer, more nutritious than polished white rice).

Oil Content in Rice Bran

Red Rice

• Iron-rich red rice is grown in the Brahmaputra valley of Assam without chemical fertilisers, known as ‘Bao-dhaan’. Valued for high iron content and antioxidant properties.
• First consignment of red rice was exported to the USA on 4 March 2021.

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Pests and Diseases

Rice faces a wide range of nutritional disorders, fungal, bacterial, and viral diseases, plus insect pests. Exam questions frequently test the cause behind named diseases — especially Khaira (zinc deficiency) and the two “killer diseases” (BLB and Tungro).

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Fluffy Paddy Soil

Under continuous flooding in a rice-rice-rice sequence, soil particles remain in constant flux and lose mechanical strength, leading to fluffiness — a serious soil health issue in intensive rice monoculture.

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Beushening / Biasi in Rice

• A traditional method prominent in Chhattisgarh, Bihar, and Odisha.
• Rice seeds are broadcast in ploughed fields after monsoon onset; the standing crop is ploughed 4-6 times later when 4-5 cm of water is standing.
• Uprooted seedlings are transplanted after biasi — called Chalai gap filling.
• Objectives: Control weeds, create semi-puddled conditions, arrest percolation loss, and adjust plant population.

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Hybrid Rice

• First developed in the late 1970s by Chinese scientist Yuan Longping (the Father of Hybrid Rice) using Cytoplasmic Male Sterility (CMS).
• In India (1994), the first five hybrid rice varieties were released: APRH 1, APRH 2 (Andhra), KRH 1 (Karnataka), MGR-1 (Tamil Nadu).
• Two years later: CNRH 1, KRH 3, DRRH-1 were released.
• PHB-71 is the only hybrid rice released by a private organisation.
• Seed rate for hybrid rice: 15 kg/ha (20 x 15 cm spacing) — lower because hybrid vigour ensures better tillering.

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Golden Rice

• Produced by combining genetic material from Daffodils, Erwinia uredovora, Agrobacterium tumefaciens, and Japonica rice by Professor Ingo Potrykus and Dr. Peter Beyer (Germany, 1999).
• Purpose: Combat Vitamin A deficiency, a major cause of childhood blindness and death from infectious diseases like measles. A biofortified crop of immense public health significance.
• Rice is naturally low in beta-carotene; golden rice contains it, giving the grain its golden colour.

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System of Rice Intensification (SRI)

SRI is based on transplanting young seedlings (8-12 days old), planting single seedlings at wider spacing, and maintaining alternate wetting and drying instead of continuous flooding. It saves five resources simultaneously:

• Leaf Colour Chart (LCC): A simple tool for nitrogen management that saves 15 kg N/ha by applying nitrogen only when the plant needs it.
• Rotary/Cono weeder is used for weeding in lowland rice.

• The first systematic work on SRI in India began at TNAU, Tamil Nadu in 1993.

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Important Rice Varieties ^{Asked in AFO/NABARD}

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Summary Table — Rice at a Glance

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Rice Cultivation: Quick Decision Guide for Field Officers

Which establishment method to recommend?

Critical growth stages — when NOT to miss irrigation:

SRI vs Conventional — evidence-based comparison (ICAR-NRRI data): SRI typically uses 25-50% less water and 80-90% less seed than conventional transplanting. Yield advantage varies from 10-30% depending on management quality. The method requires skilled labour for young seedling handling.

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Summary Cheat Sheet