Introduction to Brinjal (Solanum melongena)
- Common names: Brinjal, Eggplant, Aubergine
- Family: Solanaceae; Chromosome number: 2n=24
- Origin: Indo-Burma region; major cultivation in Asia
- Day-neutral, annual herbaceous plant
- Rich in vitamins, minerals, and phytonutrients
Botanical Features
- Plant: Erect, well-branched, large lobed leaves
- Inflorescence: Solitary or clusters (cymose)
- Flowers: Actinomorphic, hermaphrodite, hypogynous
- Fruit: Berry; variable shape, size, and color
- Heterostyly: Four flower types based on style length
Taxonomy and Species Diversity
- Main species: Solanum melongena
- Related species: S. incanum, S. integrifolium, S. nigrum, S. torvum, S. xanthocarpum
- Botanical varieties: esculentum (round), serpentinum (long), depressum (dwarf)
- Wild relatives offer resistance to diseases and pests
Origin, Distribution, and Production
- Origin: Bengal plains (India), Indo-Burma region
- Major producers: China (1st), India (2nd)
- Leading Indian states: West Bengal, Odisha, Gujarat, Bihar, Madhya Pradesh
- Area (India, 2018-19): 0.72 million ha; Production: 12.68 million tonnes
Nutritional and Medicinal Value
- Rich in Vitamin B, C, iodine, copper, iron, fiber
- Contains solasodine (glycoalkaloid) responsible for bitterness
- PUFA (linoleic, linolenic acids) aid cholesterol reduction
- Varietal differences in nutrient content (e.g., purple: copper, green: iron)
Soil and Climate Requirements
- Soil: Well-drained, fertile sandy-loam preferred; pH 5.5–6.6
- Grows on light sand to heavy clay soils
- Climate: Warm, frost-sensitive; optimal temperature 21–27°C
- Poor growth and fruiting at low temperatures
Varieties and Hybrids
- Wide variation in fruit shape, color, and size
- Popular varieties: Pusa Purple Long, Pusa Purple Round, Arka Sheel, Manjari Gota, MDU 1, CO 2
- Hybrids: Arka Navneet, Pant Brinjal Hybrid 1, Co BH 1
- Resistant/tolerant types: Bacterial wilt, shoot and fruit borer, little leaf
Seed Sowing and Nursery Management
- Sowing time varies by region; main seasons: June–July, November
- Seed rate: Varieties 400 g/ha; Hybrids 150–200 g/ha
- Spacing: 45x45 cm (dwarf) to 90x90 cm (vigorous types)
- Seed treatment: Trichoderma viride, Azospirillum
- Nursery: Raised beds, shade net, cocopeat, neem cake, biofertilizers
Grafting in Brinjal
- Rootstock: Solanum torvum commonly used
- Advantages: Nematode and root rot resistance, higher yield, extended cropping
- Ratooning possible after pruning
Cropping Systems and Intercropping
- Brinjal fits well in crop rotations and intercropping
- Leafy vegetables (spinach, amaranth) and root crops (carrot, radish) can be grown with brinjal
Nutrient Management
- Basal dose (varieties): FYM 25 t/ha, NPK 50:50:30 kg/ha
- Basal dose (hybrids): FYM 25 t/ha, NPK 100:150:100 kg/ha
- Top dressing: 50–100 kg N/ha at 30 days after planting
- Micronutrients (Cu, Zn, Mn) enhance flowering and fruiting
Irrigation and Water Management
- Regular irrigation essential, especially during flowering and fruit set
- Weekly intervals after establishment
- Drip irrigation saves water and controls weeds
- Keep soil moist during frost risk
Interculture, Weed Control, and Mulching
- 3–4 hoeings and weedings for good growth
- Earthing up essential on ridges
- Orbanche sp. (root parasite) is a major weed
- Pre-plant herbicides: Fluchloralin
- Mulching (black LDPE, Sarkanda grass) conserves moisture and suppresses weeds
Role of Plant Growth Regulators (PGRs)
- 2,4-D (2 ppm) at flowering increases fruit set and yield
- NAA, PCPA, 4-CPA promote fruit set and development
- Root-dipping in GA3 + ascorbic acid advances flowering
- Mixtalol spray enhances yield in some cultivars
Physiological Disorders
- Calyx withering: Occurs mid-February to mid-April; linked to high Ca and nitrate
- Poor fruit set: Due to prevalence of short/pseudo-short styled flowers
- Control: 2 ppm 2,4-D or 60 ppm NAA at flowering
Harvesting and Yield
- Harvest at immature, tender stage with glossy appearance
- First picking: 120–130 days after sowing
- Harvest interval: 8–10 days
- Yield: 20–40 t/ha (open-pollinated), 40–80 t/ha (hybrids)
Pest and Disease Management
- Shoot and fruit borer: Major pest; control with insecticides (Carbaryl, Monocrotophos)
- Epilachna beetle, mealy bug, leaf hopper (vector for little leaf)
- Diseases: Early blight, bacterial wilt, little leaf, mosaic virus
- Integrated management: Resistant varieties, rouging, vector control
Advanced Technologies: Bt Brinjal and Brimato
- Bt brinjal: Transgenic, contains cry1Ac gene for borer resistance
- Developed using Agrobacterium-mediated transformation
- Banned in India since 2010
- Brimato: Grafting brinjal and tomato for dual harvest (IIVR, Varanasi)
Recent Research: Spacing, Fertigation, and Ratooning
- Wider spacing (1 m x 1 m) and 100% RDF optimize yield and fruit size
- Lower fertigation (75% RDF) reduces borer incidence
- Ratooning: Cutting at 10–15 cm promotes rejuvenation and extended yield
Summary and Integrated Management
- Select suitable varieties/hybrids for local conditions
- Adopt recommended agronomic and nutrient practices
- Use grafting and resistant varieties for pest/disease management
- Implement integrated weed, water, and pest management
- Utilize advances in biotechnology and crop management for higher productivity