Improved Green Spineless (IGS)
A thornless green-fruited singhara line from the ICAR-RCER Research Centre for Makhana, Darbhanga; the 2025 review reports up to 12.0 t/ha for a Green Spineless genotype.
Quick facts
- Type
- Research-centre line (thornless germplasm)
- Season
- Kharif
- Maturity period
- Transplanted in June–July, harvested in November–December (north Bihar ponds)
- Expected yield
- Up to 12.0 t/ha reported for a Green Spineless genotype (research study, range 4.2–12.0 t/ha)
- Suitable soil
- Pond/diked-field silt (standing water)
- Disease resistance
- Not separately documented
- Release
- ICAR-RCER Research Centre for Makhana, Darbhanga (Bihar); release status not found
Actual yield depends on sowing time, soil, irrigation, weather, seed quality and crop management.
About this variety
Improved Green Spineless (IGS) is the name used here for the thornless green-fruited singhara line from the ICAR-RCER Research Centre for Makhana, Darbhanga. The 2025 review by the Centre's B. R. Jana (Agricultural Reviews 46(2)) says the maximum of 12.0 t/ha can be reached with a Green Spineless genotype, against 7.0 t/ha for Bihar Large Red (Spine), the commercial variety of Mithila, and 2.5 to 3.5 t/ha for a well-kept local type. Yields in that study ran from 4.2 to 12.0 t/ha. A 2018 Indian Farming article by Singh, Thakur and Prakash from the same Centre describes 'newly identified thornless germplasm'. No source we could read uses the words 'Improved' or 'IGS' or gives the line's release status. A thornless fruit should be easier and safer to pick and peel.
Should you pick this variety?
Choose the thornless green line if you can get planting material from the Research Centre for Makhana, Darbhanga, and want the highest published yield. The 2025 review reports up to 12.0 t/ha for a Green Spineless genotype, against 7.0 t/ha for Bihar Large Red (Spine) and 2.5 to 3.5 t/ha for a well-kept local type. Those are research figures, with a study range of 4.2 to 12.0 t/ha, so plan on the low end until you have your own results. Choose the local green-spined type if you cannot get this stock.
Sowing & cultivation
Advantages & considerations
Why farmers may choose it
- Up to 12.0 t/ha reported for a Green Spineless genotype, against 7.0 t/ha for the commercial Bihar Large Red (Spine).
- No thorns, so picking and peeling should be easier and safer than with the spined local types.
Things to consider
- Release status and planting-material supply are not published. Ask the Research Centre for Makhana, Darbhanga.
- 12.0 t/ha is the maximum in a research study (range 4.2 to 12.0 t/ha), not a farm average, and the part of the review we could read does not say whether the weight is fresh fruit.
Suitable regions
States this variety is recommended for — check locally, since a state can have more than one recommended zone.
- Bihar
What is known about the thornless line
Two documents describe it, both from the ICAR-RCER Research Centre for Makhana, Darbhanga. A 2018 Indian Farming article by I. S. Singh, A. K. Thakur and Dhiraj Prakash, 'Scientific cultivation of water chestnut crop a boon for poor fishermen', speaks of 'newly identified thornless germplasm' and reports almost two-fold higher income than the fishermen's earlier activities, and the highest benefit to cost ratio, 1.79, from a foxnut and water chestnut combination. We could read only its abstract. The 2025 Agricultural Reviews article by B. R. Jana says up to 12.0 t/ha can be had with a Green Spineless genotype.
What is not in either: a release notice, the line's formal name, how many seasons it was tested, the planting date and depth used, or how to buy stock. An ICAR-funded project on evaluating water chestnut genotypes ran from 2015 to 2020 at ICAR-RCER, Patna (Dr Rajvir Sharma, ISTI portal), and a 2024 Indian Journal of Horticulture paper evaluated 23 lines in 2020–21, but we could not open either report. If you are serious about the line, ask the Centre for those reports, since they should hold the trial detail that these two pieces leave out.
Can you keep your own planting material?
This is an open-pollinated variety, so seed from a healthy crop of your own can be sown again. Keep seed only from disease-free plants, dry it properly, store it cool and dry, and bring in fresh certified seed every three to four years so the variety does not drift.
How it compares with other varieties
Every Water Chestnut (Singhara) variety with a page on this site, side by side. The row for this page is highlighted.
| Variety | Best for | Yield | States |
|---|---|---|---|
| Improved Green Spineless (IGS)this page | Pond farmers who want a thornless singhara and can get planting material from the Research Centre for Makhana, Darbhanga | Up to 12.0 t/ha reported for a Green Spineless genotype (research study, range 4.2–12.0 t/ha) | Bihar |
| Improved Red Spineless (IRS) | Farmers who heard of a red thornless singhara and want to know what is actually published before they plan around it | No published figure found for a red spineless line | Bihar |
| Local Green-spined biotype | Farmers who want a second nut colour beside the red type in the same ponds and have buyers who ask for green singhara | 25–35 q/ha for a well-kept local type; pond-dependent | Bihar, Uttar Pradesh, West Bengal, Jammu and Kashmir |
| Local Red-spined biotype | Pond farmers in Bihar, eastern Uttar Pradesh and West Bengal who want the usual red-spined singhara and can save their own planting stock | 25–35 q/ha for a well-kept local type; pond-dependent | Bihar, Uttar Pradesh, West Bengal |
Tools for this crop
The numbers you need next: how much seed to buy, whether the lot germinates, what the fertilizer bill looks like and what Water Chestnut (Singhara) is selling for.
- Seed Rate CalculatorHow much seed your Water Chestnut (Singhara) plot needs, corrected for the germination of the lot you bought.
- Seed Variety FinderFilter every Water Chestnut (Singhara) variety on this site by state, season, duration and soil.
- Fertilizer CalculatorTurn the NPK recommendation for Water Chestnut (Singhara) into bags of urea, DAP and MOP for your field size.
- Crop Profit CalculatorPut your seed, labour and input costs against the yield you expect from this variety.
- Mandi Price CheckerToday's Water Chestnut (Singhara) rate in your nearest mandi, before you fix a price with a trader.
Subsidy and government support
Schemes that help with the cost of Water Chestnut (Singhara) seed or planting material. Rules and the application route are on each scheme page.
Frequently asked questions
Is Improved Green Spineless an officially released variety?
We could not confirm that. The sources we could read are the 2025 Agricultural Reviews article by B. R. Jana of the Research Centre for Makhana, Darbhanga, which names a 'Green Spineless genotype', and a 2018 Indian Farming article that mentions 'newly identified thornless germplasm'. Neither uses the words 'Improved' or 'IGS', and neither gives a release notice. Ask the Centre whether the line has been notified and who may multiply it.
What yield can I plan on from the thornless green line?
The 2025 review says the maximum of 12.0 t/ha can be reached with a Green Spineless genotype, and that the study's yields ranged from 4.2 to 12.0 t/ha. It puts Bihar Large Red (Spine) at 7.0 t/ha and a well-kept local type at 2.5 to 3.5 t/ha. The part we could read does not say the ponds, years or whether the weight is fresh fruit. A sensible plan is to budget at the low part of the range first and compare with a local plot in the same pond.
Where can I get planting material?
Not from an open nursery trade, as far as we found. The line comes from the ICAR-RCER Research Centre for Makhana, Darbhanga, so write to the Centre or ask your KVK to. We found no public stock list, price or quantity limit. Ask in the same letter for the release note and for trial results from ponds like yours, and keep a record of where your stock came from.
Will my saved nuts stay thornless and high-yielding?
We found no published test of this, so we cannot promise it. Singhara planting stock in ponds is normally farmer-saved, and local biotypes are known to vary from pond to pond. If you save your own, keep stock only from plants that have the thornless fruit and the best crop, and ask the Centre in Darbhanga how often to renew from its stock.
Sourced from: Jana, Recent Production and Marketing Scenarios of Water Chestnut (Trapa spp.) in India: A Review — Agricultural Reviews 46(2), 2025 (ICAR-RCER Research Centre for Makhana, Darbhanga), Singh, Thakur and Prakash, Scientific cultivation of water chestnut crop a boon for poor fishermen — Indian Farming 68(3), 2018 (abstract only), Evaluation of different genotypes of water chestnut — ICAR-RCER Patna project 2015 to 2020 (ISTI portal), Indian Journal of Horticulture, evaluation of 23 water chestnut lines, 2020–21 (seen as a search extract; the file did not open). editorial policy.