Seed Certification
Seed :: Vegetables :: Brinjal

QUALITY SEED PRODUCTION IN BRINJAL

Selection of land for quality seed production
         
The selection of land is the first and foremost task for a seed producer. The seed production plot must be selected carefully. A fertile and healthy seed plot with certainly produce quality seed. The field selected for seed production must not have been sown with brinjal in the previous season. This is done to avoid volunteer plants that cause admixture. Fields continuously cultivated with brinjal may harbour root rot or wilt pathogen. Hence, such fields must be avoided wherever possible. Following crop rotation will help to reduce endemic pathogen.
         
Soil with neutral pH must be selected. Loam or clay loam soils are best suited. Higher organic matter will lead to production of vigorous seed.

What are volunteers?
       
Volunteers are plants that grow in the field from the seeds found in the soil. These seeds should have been fallen from previous season crop. As they germinate without sowing or they volunteer to grow by themselves, hence the name volunteer plants.

Isolating the seed crop to avoid genetic contamination
         
Brinjal is a cross-pollinated crop. The certified seed production field must be 100 metres away from other brinjal variety or vegetable field. It will enable us to maintain the genetic purity and also physical mixture at the time of harvest.

Selecting the right season for raising seed crop
        
Quality of seed also depends on the season in which it is grown. Eventhough brinjal is almost grown all through the year, it is more important to select suitable season for seed crop. In brinjal, after the seed extraction, seeds should be dried under dry cool weather. Considering the above factors, for brinjal seed production, June-September is the best season.

Producing quality seedlings for transplanting
          
Selecting ripe and vigorous seed is the first step of production of robust seedling which will ultimately lead to producing quality seed. Planting robust seedling will impart disease and pest resistance and help in proper uptake of precious fertilizer applied to the main field. Proper care at nursery stage will also help in early establishment and reduce the death rate in field, hence utmost care for producing robust seedlings is important.

Seed selection
      
Selection of seeds is the first step in production of quality seed. This involves selection of seeds with the right genetic make-up of the variety to be produced. Seeds must be from an approved source. This is possible if the seed is got from the breeding firm / university research station or from the breeder himself. Verify if the seed brought has breeder seed tag (for producing foundation seed); foundation seed tag (for production of certified seed). Further, the seeds must be free from pest and diseases; Rotten, dull coloured, black spotted seeds must be removed. Seeds of uniform size and shape alone must be used for sowing.

Nursery preparation and sowing
       
The area to be used as nursery must be under partial shade, preferably near water source. The soil must be healthy and fertile. A nursery area of 3 cents is necessary to raise seedlings for transplanting in one acre. The selected area is tilled two-three times followed by addition of 1 cart load of well decomposed compost. Raised beds of 1 m width and 3 m length are made. Small depressions are created using a stick (known as rills) at 10 cm intervals. Into these rills, about 150g seeds that are treated with 300 g Carbendazim are placed and covered using sand or dry soil.
Irrigate the nursery bed till it is completely submerged followed by irrigation once in two days.

Check this out
       
The maximum width of nursery must be 3ft so that it facilitates weeding, plant protection and removal of dead plants.

Adding fertilizer to nursery
       
Fertilizer application is essential to provide robust growth to the emerging seedlings. Application of 6 kg DAP to the 3 cent nursery as basal is done which leads to prevention of root damage during pulling and earlier establishment of seedling upon transplanting in the main field. If DAP is not available, 6kg Urea and 12kg Super phosphate can be applied.

Age of seedling for transplanting
        
The right age of seedling is essential for better growth and development upon transplanting, if not planted in the right age then yield is reduced and seedlings are also susceptible for drought. Hence transplanting seedlings that are 30-35 days old is essential.

Preparation of main field and transplantation
          
Land selected for raising seed crop should be ploughed thoroughly for two (or) three times. At the last plough, 20 tonnes of FYM per acre has to be incorporated into the soil. The ridges are to be formed at distance of 75 cm.
         
After forming the ridges and furrows, the recommended doses of 44 kg urea, 180 kg super phosphate and 48 kg potash per acre has to be applied on the 1/3rd height of ridges as a basal dose. Application of basal doses of fertilizers will be more important for the early vigourous growth of the seedlings.

Transplanting
         
The healthy seedlings pulled out from well maintained nursery have to be used for transplanting. After the irrigation i.e complete soaking of ridges, single seedling should be transplanted at a distance of 60cm between plants.

Controlling weed
        
Maintaining the main field free from weeds from the beginning is more important and essential. For that we have to apply pendimethalin(Stomp-30) herbicide @ 400 ml/acre using knapsack sprayer or applied after mixing in the pure sand. After 35-40 days of transplanting one manual weeding has to be taken for further maintenance of the main field.

Earthing up
          
During the time of second weeding (45 days), the plants have grown to a height of 1.5-2.0 feet and are heavy. This leads to lodging, fruits formed on plants lying on ground tend to get infected by soil borne pathogens. Hence, after second weeding the plants are given an earthing up.

Top dressing
         
Seed crop is entirely different from vegetable crop and it needs more number of split applications of fertilizers. For brinjal, top dressing with urea 44 kg per acre before flowering is important. This will facilitate more number of flowering and fruit set as well as seed maturity.

Plant protection
         
Maintaining plant healthy is more important and hence prophylactic plant protection measure should be taken.

Fruit borer : To control fruit borer we have to follow any one of the following viz., spraying Quinalphos 25EC 250 ml/ac or carboryl wettable powder @ 2ml / liter of water or based on the ETL, Trichogramma, egg parasite may be released @ 20,000 /ac. at flowering stage.

Root knot nematode: Application of carbofuran granules @ 10 g/m2 at the time of planting.

Leaf curl virus: The virus is transmitted by white flies. To control the white flies spray methyl demeton or monocrotophos or dimethoate @ 200 ml/ac.

Maintaining seed quality by roguing
        
In the main field sometime we are noticing abnormal difference in growth habits in some of the plants and this shows the admixture of some other varieties. This may very much affect the genetic purity of that particular brinjal seed crop and ultimately the crop will not be fit for a seed crop. Hence, in the brinjal seed crop field removal of off type plants, weeds and virus infested plants is to be done scrupulously before it comes to flowering to avoid the genetic contaminations

Stages of rouging

Characters to be observed

Pre-flowering stage (or) vegetative stage and pigmentation

Plant height, number of branches, leaf and stem colour

Fruiting stage

Fruit shape, colour and size

After harvest

Fruit shape, colour and size

Harvesting
          
In brinjal harvesting has to be done in 8 to 10 pickings. The first and last one or two harvests may be taken for vegetable purpose and the fruits from remaining pickings may be used for seed extraction. The seeds from the above pickings are normally posses high vigour and germination. Well ripened fruits alone are to be harvested and medium to large size fruits may be used for seed extraction.

Optimum stage of harvest

Processing to improve seed quality
        
After the harvest, the fruits not confirming to the varietal character, small fruits and pest and disease infested fruits must be removed and only graded fruits are to be used for seed extraction.

Removal of other variety and insect damaged fruits

Seed extraction methods 
         
The seed viability depends on the method by which the seeds are extracted and hence, it is more important to choose proper method of seed extraction.
The selected fruits are to be cut into pieces and put in the cement tank with water for 10-12 hours for fermentation. The fruits can be allowed for over ripening for one or two days. This facilitates for easy pulping of fruits. Then fruits are to be made into pulp by manually. Add excess quantity of water and after ½ hour, remove the floating pulp fraction and collect the seeds settled at the bottom. For large scale seed extraction we can use the brinjal seed extractor released by Tamil Nadu Agricultural University. The seeds extracted by this machine may again be treated with concentrated HCl @ 2-3 ml/kg seed with equal volume of water for 3-5 minutes with constant stirring and then seed should be washed with water for three to four times.

Fruits selected to extract seeds

         
It is easy to dry the seeds extracted by acid method and also remove the fungus growth over the seed coat, thus seeds possess golden yellow colour and high vigour.

Brinjal seed extractor

Drying seeds to reduce moisture
         
Immediately after seed extraction, it has to be properly dried, since seeds are extracted from 100% moist condition. The extracted seeds should be spread on gunny bags in a thin layer and dried under shade for 8 to 10 hours for one or two days. Seeds can be dried under direct sunlight between 8 to 12 noon and 3 to 5 pm. Avoid drying in between 12 to 3 pm, since the rays emits from sun and the heat may affect the seed viability. While drying care must be taken to avoid clogging.

The extracted seed should not be dried directly under sun. Since seed posses high moisture it may affect the germination potential. Similar, while drying frequent stirring is more important otherwise it leads to clogging. This may results in improper drying, fungus growth and poor vigour

Seed cleaning and processing
         
After proper drying, the seed processing is essential. This will be helpful for maintaining high vigour and viability by way of removing immature and small seeds. In the processing we have to remove broken, immature, diseased seeds, other crop, weed seeds, mud and other inert matters. For processing brinjal seeds, BSS 12 x 12 wire mesh sieve should be used.

Storage of unprocessed seeds results in poor viability. In processing, the sieves must be cleaned while changing to other variety otherwise it leads to physical admixture resulting in genetic contamination. Hence, utmost care must be taken during processing of seeds to maintain quality.

Good quality Brinjal seeds

Protecting seeds during storage
        
Importance must be given for proper storage of seeds until next season as that of the importance given for production.

Moisture content
         
Seed quality mainly depends on the seed moisture. If seed moisture content is high normally it loses its viability at faster rate. For short term storage seed moisture content should be reduced to 7-8% and can be stored in cloth bag. For long term storage seed moisture content should be reduced to 6% and stored in moisture vapor proof containers.

Seed treatment
        
Seeds must be treated with fungicides before storage. The seeds may be treated with Captan or Thiram @ 4g/kg of seeds. The seeds can also be treated with halogen mixture @ 5g/kg of seed and it is an ecofriendly seed treatment.

Storage containers
          
Seeds could absorb moisture from atmosphere. Hence storing seeds in the coastal region (or) river sides we should use moisture vapour proof containers i.e. 700 gauge polyethylene bags. For seed storage every time new containers must be used.

Seed certification
            
Seed certification will give guarantee for genetic purity and other qualities. It is a legally sanctioned system for quality seed production. The supply of improved varietal seed to the farmers with high genetic purity, physical purity and germinability are being the main objectives of the seed certification.
        
Seed certification acts at different stages from sowing to issue the tags and sealing the bags. They start their function by verifying the seed source before the seeds are sown, then verifying the isolation distance followed for that seed crop, taking field inspections at different stages viz., bagging operations. In addition to these operations, it is their duty  to send samples to seed testing laboratory and after receiving the results, they will be issuing the certification tags.
         
The seeds so produced will be issued certification tag only after meeting out the prescribed field and seed standards.
         
Hence, by registering the seed production fields under seed certification we could able to produce genetically as well as physically pure seeds.   The private seed producers can also subject their seed production fields under seed certification for quality seed distribution.
 For more details contact the seed certification officers nearby area.

Minimum certification standards

Field standard

 

Off types (maximum)

0.20%

Plants affected by seed borne diseases (maximum)

0.50%

Seed standards

 

Pure seed (minimum)

98.0%

Inert matter (maximum)

2.0%

Other crop seeds (maximum)

None

Weed seeds (maximum)

None

Germination (minimum)

70%

Moisture previous container (maximum)

8.0%

For vapors proof containers (maximum)

6.0%

 

 
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