SEED PRODUCTION

SEED PRODUCTION

  • Rhubarb grown for seed production is planted in a field for 2 years in which the stalks and petioles are not harvested.
  • After 2 years of growth, the roots are ready to be dug for seed production.
  • It should be exposed to the low temperature to break the dormancy.
  • The crown and roots used for seed production must be dug before the soil freezes, taken for storage, and held where dehydration and water loss are at a minimum until it used for planting.
  • When ready for planting, the crowns are packed together on 4-5 ft wide beds with soil and water added to initiate growth, and then placed in the dark.
Land Requirements
Before planting this polygonaceous crop, consider the following important factors:
  • No polygoneous crop (Sorrel) or related weed (dock plants) has been present in or near the field for at least 2 years, preferably 4 years.
  • Polygoneus crop like Buckwheat and polygoneous crops waste should not have been dumped on these fields.
  • Soil should be well drained.
  • Rhubarb prefers deep, fertile loamy soils and does best in slightly to moderately acid soils.
Methods of Seed Production
  • There are two major methods used to produce seeds in Rhubarb:
    • Seed to seed method
    • Root/crown to seed method
  • Out of these two methods, root or crown to seed method is commercially used for quality seed .production.
Rouging
  • Timely and regular interval rouging for off type, diseased plants affected by crown rot and viral diseases
  • Weed like dock plant etc. is removed at regular interval.
  • Rest of the cultural practices is same as described for table crop.
Harvesting and Yield
  • The best time to harvest a seed crop is at stage when the highest yield of best quality seeds will be obtained which is standardized by experience.
  • Seed crops are harvested when plant start drying in the field and seed are usually dried on the plant before harvesting.
  • Plants are manually harvested by cutting at ground level or whole plant pulls up and threshed to remove the seeds.
  • Seed crop starts giving seed harvests from three years age onwards.
  • Seed yield varies between 2.5-4.0 q/ha.
Seed Packaging
  • Well dried seeds are packed in the plastic bags, tin cans, cloth bags etc.
Seed Storage
  • Seed can be stored at 0– 2oC and a relative humidity of 95-100 per cent for 1-2 years.
  • Good air circulation is also essential.
SEED CERTIFICATION STANDARDS
A. Field Inspection
a) Mother roots/ crowns production stage:
  • Minimum two inspections are required to produce quality seeds.
  • The first inspection is done 20-30 days after the sowing in order to determine proper isolation, volunteer plants, out crosses, off types and other relevant factors.
  • The second inspection is done after the mother roots have been lifted to verify the true characteristics of roots.
b) Seed production stage:
  • A minimum of one inspection is done during flowering to check isolation, off types and other relevant factors.
B. Field standards
a. General requirement
Isolation:
Seed fields should be isolated from the contaminants as shown below:
     
Contaminants Minimum Distance (meters)
Mother Root production stage
Seed production stage
Foundation Seed Certified Seed
 Foundation Seed Certified Seed
Fields of the other varieties of the same species 5
 5
 1600
 1000
Fields with same variety not confirming to varietals purity requirement 5
 5
 1600
 1000

b. Specific Requirements
Factor
Maximum permitted (per cent)
Foundation Seed Certified Seed
Off type 0.10
 0.20
Plant affected by seed borne diseases
0.10
 0.50

B. Seed Standards
Factors
 Foundation Certified
Pure seed (minimum) % 98
 98
Inert matter (maximum) % 2
 2
Other crop seeds (maximum) Number/ kg 5
 10
Weed seeds (maximum) Number/ kg 10
 20
Germination (minimum) % 60
 60
Moisture (maximum) % 7-9
 7-9
For vapour proof containers (maximum)% 5
 5


Last modified: Monday, 11 June 2012, 12:40 AM