Grafted Brinjal Cultivation

🔬 Grafting Technology — How It Works

TNAU has officially released this technology and trained Tamil Nadu farmers in grafting brinjal onto Solanum torvum (Sundakkai / Turkey Berry) rootstock. The grafted root system is deep, vigorous, resistant to bacterial wilt and nematodes, and allows the crop to be kept for 12–18 months with ratooning — giving 3× the yield of conventional planting.

🌿 Rootstock — Solanum torvum (Sundakkai)

📍 Found in: Roadsides, graveyards, hedges across TN

⏱ Sow rootstock: 55–60 days before grafting (slow germinator)

🦠 Wilt resistance: Near-complete (Ralstonia solanacearum)

🪱 Nematode resistance: Yes — deep roots escape nematode zone

💧 Drought tolerance: Deep root system, needs less water

🌱 Germination tip: Soak seeds in GA₃ 1500ppm × 24 hrs to improve germination rate

🍆 Scion — High Yielding Variety or Hybrid

📍 Sow scion: 25–30 days before grafting (30 days old at grafting)

✅ Compatible scions (TNAU): CO 2, Dhruva, PLR-2, COBH 1

✅ Private hybrids: Mahy-11, Galine F1, COBH 1 (96%+ success rate)

📏 Grafting stage: Stem diameter 3–4 mm, 2–3 true leaves

⚠️ Key: Scion and rootstock stem diameter must match at grafting point

📅 Stagger sowing: Sow rootstock first, then scion 25–30 days later

🪴 Step-by-Step Grafting Process (Cleft Method)

🌱

Prepare Rootstock

55–60 day old S. torvum at 3–4mm stem. Behead at 5–7 cm from ground. Make a 1–1.5 cm vertical slit down center of cut stem.

Day 0

✂️

Prepare Scion

30 day old brinjal seedling. Cut stem 5–7 cm from tip. Make a V-wedge cut (2 cm) at base of scion. Keep 2–3 leaves on top.

Day 0

🔗

Join & Clip

Insert V-wedge scion into rootstock slit. Align cambium layers on at least one side. Secure with grafting clip or polythene strip. Work quickly — cambium dries fast.

Day 0

🌫️

Mist Chamber

Place grafted plants in mist chamber 3–15 days. Maintain 85–95% humidity, 25–30°C, dark for first 3–4 days. Mist frequently. Union forms in 10–11 days with S. torvum.

Day 0–15

🌤️

Shade Net Hardening

Transfer to 50% shade net for 15 days. Gradually increase light exposure. Scion leaves will recover fully. Check union is firm before transplanting.

Day 15–30

🌿

Field Planting

45 days after grafting, plant in field. Spacing: 1.0 × 1.0 m (wider than traditional to use full vigour). Ensure graft union is above soil level at all times.

Day 45

💡 Success Rate: 83–97% graft success with S. torvum rootstock (TNAU research, Coimbatore). Use sharp sterile blades for every cut.

🛒 Buy Ready-Grafted: Available from private nurseries in Coimbatore, Krishnagiri, Vellore. Cost: ₹8–18/plant depending on scion variety and nursery.

🍆 Recommended Scion Varieties for Tamil Nadu

These varieties are proven compatible with Solanum torvum rootstock in TNAU field trials. Any high-yielding variety or F1 hybrid can be used as scion.

🍆

CO 2

TNAU · Open Pollinated

TNAU Coimbatore variety. Grafting compatibility confirmed by TNAU Cleft Grafting studies. Round purple fruits, good shelf life. Grafted yield 3× ungrafted.

🌿 Grafted Yield: 22–28 t/acre · Duration with ratoon: 12–14 months

🍆

Dhruva

TNAU · Open Pollinated

TNAU research-proven scion. 88.75% field survival rate when grafted on S. torvum (TNAU Coimbatore study). Long purple fruit, good market acceptance.

🌿 Grafted Yield: 22–26 t/acre · Duration with ratoon: 12–14 months

🍆

COBH 1

TNAU · F1 Hybrid

TNAU's first F1 hybrid. Vigorous plant, long dark purple fruits. Excellent for grafting — the vigorous rootstock enhances hybrid advantage. Drip irrigation + mulch recommended.

🌿 Grafted Yield: 26–32 t/acre · Duration with ratoon: 14–16 months

🍆

Mahy-11 (Private F1)

Private Hybrid

Research-proven highest yield combination. Grafted yield 61.11 t/ha (25 t/acre) in trials. 94.44% graft success rate on S. torvum. Long dark fruits, high fruit weight.

🌿 Grafted Yield: 25–30 t/acre · Duration with ratoon: 14–16 months

🍆

Galine F1 (Private)

Private Hybrid

96.67% graft success on S. torvum — highest success rate in research trials. Early bearing, consistent fruit size. Popular among nurseries in Coimbatore district.

🌿 Grafted Yield: 24–30 t/acre · Duration with ratoon: 14–16 months

🍆

PLR 2

TNAU · Open Pollinated

TNAU Coimbatore release. Confirmed compatible with S. torvum rootstock in bacterial wilt resistance trials. Long purple fruit, popular in Tiruppur and western TN districts.

🌿 Grafted Yield: 20–24 t/acre · Duration with ratoon: 12–14 months

📅 Seasonal Growing Calendar

Grafted brinjal can be grown in all 3 seasons. Plan rootstock sowing 55–60 days before target transplanting date.

Kharif

Season 1 – Kharif

Rootstock sow: April–May
Scion sow: May–June
Transplant: June–July
Harvest: Oct–Nov onwards
Higher SFB pressure. Pheromone traps essential.

★ Best

Season 2 – Rabi (Best)

Rootstock sow: July–Aug
Scion sow: Aug–Sep
Transplant: Sep–Oct
Harvest: Jan–Mar onwards
Best quality & price. Lower pest pressure.

Summer

Season 3 – Summer

Rootstock sow: Nov–Dec
Scion sow: Dec–Jan
Transplant: Jan–Feb
Harvest: Apr–Jun onwards
Good market prices. Drip irrigation critical.

🌍 Soil & Climate Requirements

🌍 Soil Requirements

Soil TypeSandy Loam / Red Loam / Clay Loam

pH Range5.5 – 6.8 (ideal)

DrainageWell-drained — essential

Organic Matter> 0.75% (add FYM 25 t/ha)

Best DistrictsVellore, Krishnagiri, Coimbatore, Dindigul, Tirunelveli

💡 Grafting advantage: S. torvum rootstock tolerates wider soil variability including wilt-sick plots where traditional brinjal fails completely.

🌡️ Climate Requirements

Optimal Day Temp25–32°C

Night Temp18–25°C

Grafting Humidity85–95% (mist chamber)

Rainfall500–750 mm/season

Sunlight6–8 hrs/day

💡 Note: Grafted plants are more drought-tolerant than traditional due to deep root system — but consistent drip irrigation during fruiting is still critical for maximum yield.

🌱 Field Cultivation Process (After Grafting)

🚜

Land Preparation

Deep plough 3–4 times. Apply FYM 25 t/ha (10 t/acre). Apply neem cake 100 kg/acre. Form ridges at 1.0 m spacing. Lay black LDPE mulch 25 micron before planting.

🌿

Transplanting

Plant 45-day-old grafted seedlings at 1.0 × 1.0 m spacing. ~4000 plants/acre. Keep graft union 3–5 cm above soil. Dip roots in Azospirillum + Phosphobacteria slurry. Transplant in evening.

🔧

Early Crop Management

Remove any rootstock suckers immediately — S. torvum sprouts vigorously below graft union. Stake at 40 cm height. Earthing up at 30 DAT. Train 2–3 main stems only.

🍆

Harvest (Main Crop)

Harvest begins 60–90 DAT. Pick every 5–7 days at glossy firm stage. Main crop continues 5–6 months. Total yield ~70 t/ha (28 t/acre). Use scissors — never pull.

✂️

Ratoon (Cut-Back)

After main crop, cut all branches back to 20 cm from base. Apply ratoon NPK (100:150:200 kg/ha). Irrigate well. New shoots emerge in 10–15 days. First ratoon gives ~45 t/ha (18 t/acre).

♻️ Ratoon Crop System — Maximum Value from One Planting

The S. torvum rootstock makes the grafted plant perennial in nature. Cut-back (ratooning) regenerates the crop and gives 2 additional harvest cycles from the same plant, dramatically improving cost-benefit ratio.

Main Crop

70 t/ha · 28 t/acre

Transplanting → 5–6 months
NPK: 125:175:125 kg/ha basal
+ 125 kg N/ha top dress at 30 DAT
Harvest every 5–7 days

First Ratoon (Cut-back)

45 t/ha · 18 t/acre

After main crop harvest
Cut branches to 20 cm from base
NPK: 100:150:200 kg/ha
New shoots emerge in 10–15 days

Second Ratoon

40 t/ha · 16 t/acre

Second cut-back after 1st ratoon
Same NPK: 100:150:200 kg/ha
Total: ~155 t/ha / 62 t/acre
over 12–18 months from one planting

⚠️ Critical: Remove all S. torvum suckers (shoots from below graft union) immediately — they are vigorous and will dominate if left. Check at every field visit.

🌿 Fertilizer Schedule (per Acre) — Grafted Brinjal

⚗️ Main Crop — Basal (At Transplanting)

FYM10 t/acre (25 t/ha)

Urea (N)50 kg N/acre

SSP (P)71 kg P₂O₅/acre

MOP (K)50 kg K₂O/acre

Neem Cake100 kg/acre

Azospirillum0.8 kg/acre

⚗️ Main Crop — Top Dress (30 DAT)

Urea (N)50 kg N/acre

Boron foliar0.2% spray

ZnSO₄ foliar0.5% spray

MgSO₄ foliar1.0% spray

Calcium Nitrate5 g/L at flowering

⚗️ Ratoon Crop — Per Cut-Back

Urea (N)40 kg N/acre

SSP (P)61 kg P₂O₅/acre

MOP (K)80 kg K₂O/acre

Seaweed2 ml/L foliar

Multi-K 13:0:453 g/L foliar

📌 TNAU Official Dose (Grafted Brinjal): Main crop NPK = 125:175:125 kg/ha (50:71:50 kg/acre). Ratoon NPK = 100:150:200 kg/ha (40:61:80 kg/acre). Higher K in ratoon promotes shoot regeneration and fruiting.

🌿 Organic Alternatives — Shop-Ready Products

🌱 Organic Basal (At Transplanting)

Vermicompost 2–3 tKamdhenu / Varsha bags

Neem Cake 100 kgAgrifit / Godrej Neem Cake

Iffco PROM 100 kgIffco outlets · ₹12/kg

Azospirillum 0.8 kgTNAU packet / Bio-Cure-N

Pseudomonas 0.8 kgTNAU / Multiplex Bio-Cure-P

🌿 Organic Top Dress (30 DAT)

Panchagavya 3%Gou Amrit / TNSF

Seaweed 2–3 ml/LIffco Sagarika / Biozyme

Humic Acid 2 kgMultiplex Humax

Vermiwash 10%Biofit Vermiwash

VAM Mycorrhiza 5 kgEndo Root / Myco-riz

🍆 Organic Ratoon Crop Support

Fish Amino 3 ml/LCoromandel Amino Power

SOP 10 kgIffco MKP/SOP

Seaweed 2 ml/LSea-K / Iffco Sagarika

KMB 0.8 kgMultiplex K-Max / TNAU KMB

Calcium Boron 2 ml/LMultiplex Cal-Max

🦠 Key Pests & Diseases in Tamil Nadu

✅ Grafting eliminates bacterial wilt risk almost completely. Remaining threats are above-ground — Shoot & Fruit Borer is the #1 priority for grafted brinjal.

Shoot & Fruit Borer

Leucinodes orbonalis · #1 Threat

VERY HIGH

🏪 Chemical Options

Coragen (Chlorantraniliprole) 0.3 ml/L

Emamectin Benzoate 0.4 g/L

Bt (Bacillus thuringiensis) 2 g/L

Rynaxypyr 0.3 ml/L · systemic

🌿 Organic Options

🪤 Pheromone traps 8/acre from 30 DAT · NSKE 5% spray · Neem oil 3% · Remove infested shoots weekly

Aphids & Whitefly

Aphis gossypii · Little Leaf Vector

HIGH RISK

🏪 Chemical Options

Imidacloprid 0.3 ml/L · Bayer

Thiamethoxam 0.5 g/L · Syngenta

Acetamiprid 0.5 ml/L

Dimethoate 1 ml/L

🌿 Organic Options

🟡 Yellow Sticky Traps 10/acre · Neem oil 2% spray · Verticillium lecanii biocontrol

Little Leaf Disease

Phytoplasma · Leafhopper-spread

HIGH RISK

🏪 Control Vector

Imidacloprid 0.3 ml/L systemic

Thiamethoxam 0.5 g/L drench

No cure — prevention only

🌿 Prevention

⚠️ Remove & burn infected plants. Yellow sticky traps. Border crop of maize. Resistant variety scion.

Bacterial Wilt

Ralstonia solanacearum — CONTROLLED BY GRAFTING

LOW (Grafted)

✅ Grafting is the most effective solution for bacterial wilt — far superior to chemical drenches. All S. torvum and S. melongena (Surya, SM series) rootstocks showed high resistance in TNAU and Springer research trials. Maintain Pseudomonas fluorescens drench at transplanting as extra insurance.

💧 Irrigation Management

Crop Stage	Frequency	Notes
Post-transplant (Week 1)	Daily × 7 days	Ensure graft establishment. Don't wet graft union directly.
Vegetative Growth	Every 3–4 days	Grafted roots go deeper — less frequent irrigation needed vs traditional
Flowering	Every 2–3 days	Critical — moisture stress causes flower drop
Fruiting (Main Crop)	Every 3–4 days	Consistent moisture prevents cracking and improves fruit size
After Ratoon Cut-Back	Daily × 5 days	Irrigation immediately after cutting encourages fast shoot regeneration
Ratoon Fruiting	Every 3–4 days	Same as main crop fruiting phase

💧 Drip Irrigation: Mandatory for grafted brinjal at 1.0 × 1.0 m spacing. Use 2 drip laterals per bed at 4–6 L/plant/day during fruiting. Black LDPE mulch + drip saves 40–50% water vs flood irrigation and prevents splash-spread of soil-borne pathogens.

💰 Economics of Cultivation (1 Acre) — Grafted Brinjal

📋 Cost of Cultivation

Land Preparation & Tillage₹4,000

Grafted Seedlings (~4000 @ ₹10–18)₹40,000–72,000

Manures & Fertilizers (Main + 2 Ratoons)₹14,000

Pesticides & Plant Protection₹5,000

Drip Irrigation (amortised)₹8,000

Mulch Film (Black LDPE)₹5,000

Labour (Transplant + Harvest × 12 months)₹18,000

Staking & Miscellaneous₹4,000

Total Cost (with nursery-bought grafts)₹98,000–1,30,000

📈 Income & Returns (12–18 months)

Main Crop Yield~28 t/acre (70 t/ha)

First Ratoon~18 t/acre (45 t/ha)

Second Ratoon~16 t/acre (40 t/ha)

Total Yield~62 t/acre

Average Farm Price₹8–18/kg

Gross Income₹4.96L – ₹11.16L

Net Profit (avg price ₹10)₹3.7L – ₹5.2L/acre

💡 Own nursery advantage: Farmers who graft their own seedlings (cost ~₹3–4/plant) reduce input cost by ₹25,000–50,000/acre, significantly improving margins. TNAU provides training.

🌍 Yield Comparison: Grafted vs Traditional vs World Best

Traditional Brinjal in TN (Non-Grafted)

6–10 t/acre

🏆 Grafted Brinjal TN (Main Crop Only)

25–28 t/acre

🌟 Grafted TN (Main + 2 Ratoons, 12–18 mo)

60–65 t/acre

Research Best (Mahy-11 on S. torvum)

25 t/acre (61 t/ha in trial)

🇳🇱 Netherlands (Greenhouse)

35–45 t/acre*

*Netherlands greenhouse figures not directly comparable. Source: TNAU field trials, Springer research 2021–2024.

💡 Expert Tips for Tamil Nadu Grafted Brinjal Farmers

🌱

Stagger rootstock sowing by 25–30 days before scion. S. torvum is slow to germinate — treat seeds with GA₃ at 1500 ppm for 24 hours to dramatically improve germination rate before nursery sowing.

⚠️

Remove S. torvum suckers ruthlessly — any shoot sprouting below the graft union is wild rootstock growth. If left unchecked, the vigorous S. torvum will dominate the scion. Check at every field visit.

🪤

Install pheromone traps for Shoot & Fruit Borer (8 traps/acre) from 30 DAT. Grafting removes wilt risk but SFB is still your #1 yield loss factor — don't skip this step.

💧

Black LDPE mulch is non-negotiable for grafted brinjal at 1.0 × 1.0 m spacing. It controls weeds (the wide spacing creates weed pressure), retains soil moisture, and reflects silver light to deter aphids if silver-coated side used.

✂️

Ratoon timing matters: Cut back immediately after the main crop flush ends — don't wait. Apply water and fertilizer within 24 hours of cutting. The faster you irrigate post-cut, the faster new shoots emerge and the higher ratoon yield.

🎓

Learn grafting from TNAU — the university has trained 300+ TN farmers and the technology is officially released. Contact TNAU Coimbatore KVK or your District Horticulture Officer. Own-farm grafting cuts seedling cost by ₹6–14/plant.

Get Help in Tamil Nadu: TNAU KVK Coimbatore · District Horticulture Officer · Uzhavan App · TNAU Helpline: 1800-425-1552

📍 Ground Reality in Tamil Nadu — Why Grafting Is Taking Over

😟 Problems with Traditional Brinjal in TN

🦠 Bacterial Wilt (Ralstonia solanacearum) — First confirmed in TN by Selastin Antony et al. 2015; now endemic in most districts. Entire crop can wilt within 5–7 days of symptom onset. No chemical cure.

🪱 Root-Knot Nematode (வேர்ப்புழு) — Severe in sandy loam soils of Theni (Andipatti), Dindigul, Krishnagiri. Farmers in Andipatti region reported mass infestation in 2023. Damages roots → poor nutrient uptake → low yield even without wilt.

📉 Short crop life — Traditional brinjal only lasts 4–5 months. Market price is volatile; if price crashes during that window, entire season income is lost.

💸 Repeat planting costs — Must re-invest in seedlings, land prep, and labour every 4–5 months.

✅ How Grafting Solves All of These

🦠 Wilt — Solved: S. torvum rootstock has near-complete resistance to Ralstonia solanacearum. TNAU trials confirmed 0% wilt incidence in grafted plants on S. torvum even in sick plots.

🪱 Nematode — Solved: S. torvum's deep, vigorous root system physically escapes the nematode zone + carries biochemical resistance. Confirmed by multiple trials including TNAU Coimbatore.

📅 Long crop life: 12–18 months from one planting with ratoon system. Spreads price risk over 3 harvest cycles. One bad-price window doesn't ruin the investment.

💰 Economy: Higher seedling cost (₹10–18 vs ₹2–3 for traditional), but 3× yield and 3× crop duration makes ROI far superior.

📈 Brinjal Market Price Reality in Tamil Nadu

₹20

Avg farm price/kg
(DOAC 2005–2023)

₹4–8

Price crash floor
(oversupply periods)

₹45–80

Peak price/kg
(Dec 2021 record ₹80)

₹30,000/t

White Long export price
(Dharmapuri belt 2023)

💡 Ratoon strategy is key for price risk management: With 3 harvest cycles over 12–18 months, grafted brinjal farmers capture at least one high-price window. A traditional farmer with a single 4-month cycle may miss the peak entirely. Dharmapuri farmers growing White Long variety for export are currently fetching ₹30,000/tonne — grafted plants with longer duration maximise this opportunity.

🗺️ Key Brinjal Growing Districts in Tamil Nadu

Vellore & Krishnagiri
Major commercial belt. Grafted seedling nurseries active. Export to other states.

Dharmapuri (Balakode)
White Long variety exported. 4 t/week/acre reported. Strong nematode pressure → grafting critical.

Theni (Andipatti)
Root nematode (வேர்ப்புழு) major issue confirmed 2023. Grafted S. torvum directly addresses this.

Dindigul (Oddanchatram)
One of TN's largest vegetable markets. Mix of traditional and grafted cultivation.

Coimbatore & Salem
TNAU research hub. Trained 300+ farmers. Grafting nurseries well-established.

Trichy & Namakkal
Growing adoption of grafted brinjal. TNAU extension reaching these areas.

Grafted BrinjalCultivation

🌍 Soil Requirements

🌡️ Climate Requirements

🏪 Chemical Options

🌿 Organic Options

🏪 Chemical Options

🌿 Organic Options

🏪 Control Vector

🌿 Prevention

📋 Cost of Cultivation

📈 Income & Returns (12–18 months)

Grafted Brinjal
Cultivation