
Cultivation of Wheat (Triticum aestivum)
- Botanical Name: Triticum aestivum
- Family: Graminae / Poaceae
- Chromosome Number: 2n = 42
- Origin: Southwest Asia (Turkey)
- Inflorescence: Ear or spike
- Seed: Caryopsis
- Test Weight: 40 grams (Phalaris minor test weight: 2 grams)
- Fruit Type: Caryopsis
- Photosynthetic Pathway: C3
- Day Length Requirement: Long-day plant
- Protein Content: 8-11%
- Shelling Percentage: 60%
General Information
- Wheat is the king of cereals, ranking first in both area and production worldwide.
- It contains gluten, a spongy protein essential for baking.
- The Perling Index in wheat determines the grain’s hardness.
- Clonal roots develop at the crown root initiation (CRI) stage, below the soil surface after the first leaves appear.
- Wheat is commonly intercropped with mustard.
- The gene responsible for dwarfness in wheat, Norin-10, was discovered by Dr. Borlaug in 1960 in Mexico and was instrumental in the Green Revolution in India.
- The flowering portion of wheat is called the spike or ear.
- Non-traditional areas for wheat cultivation in India include West Bengal (Northeast India).
Classification of Wheat
Common Bread Wheat (Triticum aestivum):
- Hexaploid (2n = 42), the most widely grown type, accounting for 87% of wheat area in India.
- Good for chapati and bakery products.
- Introduced to India by Dr. Borlaug as Mexican dwarf wheat, leading to the Green Revolution.
Durum/Macaroni Wheat (Triticum durum):
- Tetraploid (2n = 28), used for suji and semya.
- Occupies 12% of India’s wheat area, mainly in Central and Southern India under rainfed conditions.
- Notable varieties: Jairaj, Malavika.
Emmer Wheat (Triticum diccocum):
- Tetraploid (2n = 28), occupies 1% of wheat area, primarily in Gujarat, Maharashtra, Andhra Pradesh, Karnataka, and Tamil Nadu.
- Used for Uppumav (South Indian dish).
Diploid Species:
- Triticum monococcum (2n = 14)
- Triticum aegiloploid (2n = 14)
Area and Production (India)
- Area: Uttar Pradesh > Madhya Pradesh > Punjab
- Production: Uttar Pradesh > Punjab > Haryana
- Productivity: Highest in Punjab (45 q/ha), mainly due to irrigation and higher fertilizer application.
Critical Stages for Irrigation
- Crown Root Initiation (CRI): Occurs 21 days after sowing, the most critical stage for irrigation.
- Tillering Stage: Up to 40-45 days after sowing.
- Jointing Stage: Up to 60-65 days after sowing.
- Flowering (Booting) Stage: Up to 80-85 days after sowing.
- Milking Stage: Up to 100-105 days after sowing.
- Dough Stage: Up to 115-120 days after sowing.
If only one irrigation is available, apply it at CRI stage. For two irrigations, apply them at CRI and flowering stages.
Climate Requirement
- Germination Temperature: 20-25°C
- Vegetative Growth: Cool and moist weather.
- Grain Formation: Warm and dry weather.
Varieties of Wheat
- Dwarf Varieties:
- Single Gene Dwarf: Lerma Rojo 64-A, Sujata, Girija, Sonalika (developed from HD 1553 and RR 21).
- Double Gene Dwarf: Kalyan Sona, Sonaro-64, Chhoti Lerma, HD-2009 (Arjun), HD-2329, Janak.
- Triple Gene Dwarf: Heera, Moti, Lal Badshah (developed in 1970).
- Mutant Varieties: Sharbati Sonora (from Sonoro 64), Pusa Lerma (from Lerma Rojo 64-A).
- Other popular varieties: Sujata, Shailaja, Malavia-12, PBW-502.
Seed Rate
- Normal Sowing: 100 kg/ha
- Late or Broadcasting: 125 kg/ha
- Dibbling: 25-30 kg/ha
Spacing
- Irrigated Wheat: 22.5 x 10 cm spacing
- Sowing Time: Best time for sowing is the 1st fortnight of November, while rainfed wheat is sown in the 2nd fortnight of October.
Fertilizer Requirement
- Nitrogen: 120 kg/ha
- Phosphorus: 60 kg/ha
- Potash: 40 kg/ha
Under rainfed conditions, a thiourea spray (0.5%) can enhance yield by 10-15%.
Weed Management
- Monocot Weeds:
-
- Phalaris minor (mimicry weed): Control with Isoproturon (0.75 kg/ha) at 30-35 days after sowing.
- Avena fatua (wild oat): Control with Tribunil (banned in India) or Sulfosulfuron (20 g/ha) or Metasulphuron (4 g/ha).
- Dicot Weeds:
-
- Chenopodium album, Anagallis arvensis, Melilotus spp.
- Control with 2,4-D Eater Salt (500 ml/ha) as a post-emergence herbicide at 30-35 DAS.
- Objectionable Weed: Convolvulus arvensis.
- Rice in wheat: Example of a relative weed.
Storage
- Safe Moisture Content: 10-12%
- Harvesting Moisture Content: 20-30%
Intercropping
- Wheat + Mustard Intercropping: Recommended ratio 9:1.
- Biofertilizer: Azotobacter is used for wheat
