Grafted Female Selection

Guaranteed female / hermaphrodite bearing plants; uniform, predictable yields and quality; faster onset of bearing (4–5 years vs 8–10 for seedlings); canopy control through grafting height

Key facts

Figures are indicative, compiled from public agricultural sources (ICAR institutes, State Agricultural Universities, the Spices Board and the National Innovation Foundation) and vary with soil, season and management. Confirm with your local package of practices.

Grafted Female Selection in detail

Vegetatively grafted plants from elite female or hermaphrodite trees, with sex confirmed at planting and bearing typically beginning in 4–5 years, requiring only minimal male pollinator support.

Origin & story

Grafted female selections come out of the Kerala and Tamil Nadu nutmeg-growing regions and are propagated through institutional and commercial nurseries. Two institutional varieties are widely distributed as grafts: IISR Viswasree (released 2001) and IISR Keralashree (released 2013), both developed by ICAR-IISR. Keralashree was the first nutmeg variety developed through farmer-participatory breeding, originating as a selection from seedlings raised from an elite mother tree at Burliar, Nilgiris, Tamil Nadu. These selections address the long-standing problem of seedling nutmeg segregating roughly 1:1 male to female, with the sex of a tree not apparent until several years of growth.

How it grows

Grafted plants are produced mainly by epicotyl grafting, and also by approach grafting, patch budding, or air layering, typically onto Myristica fragrans rootstock (M. beddomei and M. malabarica are also used). Scion material is taken from confirmed female or hermaphrodite bearing trees. Grafts begin commercial harvest around years 4–5, against 8–10 years for seedlings. Spacing is generally about 8–10 m between plants. Canopy can be kept low and manageable through grafting height and periodic pruning. Only about one male graft is needed per 10 female plants, which improves land use compared with seedling plantings.

Quality & character

Female and hermaphrodite plants only. IISR Viswasree: nut oil 7.14%, mace oil 7.13%, myristicin in nut 12.48%, nut recovery 70%, mace recovery 35%; bushy, compact plant type; low incidence of fruit rot caused by Diplodia spp. By the 8th year it yields about 480 kg mace and 3,122 kg dry nut per hectare. IISR Keralashree: oil rich in sabinene with low myristicin and elemicin; mace entire, thick and dark red; about 480 kg mace and 3,122 kg nuts per hectare by year 8, rising to about 1,512 kg mace and 7,560 kg nuts per hectare by year 10.

Why it matters to buyers

Grafted plants reduce establishment risk by giving you confirmed female or hermaphrodite trees, so you avoid the loss of clearing male plants years into growth. Earlier and more predictable bearing (about 4–5 years versus 8–10) shortens the payback period, and uniform stock means more consistent quality and yield. Needing fewer male plants improves land use. Adoption across Kerala and Tamil Nadu means nursery availability is reasonably good, and plants sourced from IISR and KAU come with institutional backing.

Other nutmeg varieties

• IISR Viswasree
• IISR Keralashree
• Punnathanam Jathy
• Local Kerala Homestead Seedlings
• Seedling (Myristica fragrans)
• Hermaphrodite / Bisexual Forms
• Thrissur Type (Regional Landrace)
• Ernakulam Type (Regional Landrace)
• Idukki High-Range Type
• Myristica fragrans (Species)