Grafted brinjal seedlings
Grafted brinjal seedlings combine a commercial brinjal (Solanum melongena) scion with the wild brinjal Solanum torvum as rootstock to confer broad-spectrum resistance to soil-borne diseases that limit brinjal yields in tropical soils. The technique has been validated by ICAR-IIHR Bengaluru and is propagated commercially through specialised vegetable nurseries.
Rootstock and scion
- Rootstock: Solanum torvum (Turkey berry, wild brinjal), highly resistant to bacterial wilt (Ralstonia solanacearum), Verticillium and Fusarium wilts and root-knot nematodes (Meloidogyne incognita).
- Scion: any commercial brinjal hybrid or open-pollinated variety, including long-fruited, round and cluster types.
- Graft type: tube grafting or cleft grafting at the 2-4 leaf stage in a controlled healing chamber at 28-30 deg C and 90-95% relative humidity.
Mode of action
The torvum rootstock isolates the susceptible scion from soil-borne pathogens and from root-knot nematodes that destroy non-grafted brinjal in infested fields. Beyond disease tolerance, torvum's vigorous root system supports a larger canopy and prolongs the productive life of the plant, particularly in ratoon brinjal systems.
Performance
Independent published trials report grafted brinjal yielding approximately 9 kg per plant against around 4.8 kg per plant for non-grafted controls of the same scion, with the gain attributable to disease escape, vigour and extended duration. Grafted plants also tolerate flooding and waterlogging better than seedling-raised brinjal.
Adoption context
Grafted brinjal is most economic for high-value vegetable growers on land with a known wilt or nematode history, where non-grafted brinjal repeatedly fails. The grafted seedling carries a substantial price premium over seedling-raised plants, but is recovered through yield and extended harvest period. Indian commercial vegetable nurseries, particularly in Karnataka, Maharashtra and Tamil Nadu, produce grafted seedlings to order.
Related entries
See also: Grafted Ridge Gourd, Kadiyam Nursery Belt, Fruit Research Station Sangareddy, Kashmir Saffron Corms.
References
- Grafting in Brinjal for Sustainable Yield. Vegetos (Springer).
- Solanum torvum as a Compatible Rootstock. Longdom Open Access.