COTTON  (Gossypium spp.)HYBRIDS

 

I. Application and Amplification of General Seed Certification Standards

 

A. The General Seed Certification Standards are basic and together with the following specific standards 

     constitute the standards for certification seed of cotton hybrids.

 

B. The General standards are amplified as follows to apply specifically to the hybrids of cotton:

 

1. Eligibility requirements for certification if male sterile lines are used for producing hybrid seed:

 

(a) An inbred line to be eligible for certification shall be from a source such that its identity may 

     be assured and approved by the Certification Agency.

 

(b) Hybrid seed to be eligible for certification shall be the progeny of two approved  inbred lines,     

     one of which shall be male sterile.

 

2. Classes and sources of seed

 

 (a) An inbred line shall be a relatively true breeding strain resulting from self -pollination with selection.

 

(b)  The  Foundation class seed shall consist of an approved male sterile line to be used as a female parent

       and an approved inbred line to be used as a male parent for the purpose of  producing hybrid seed.

 

(c)  A male sterile line shall be a strain (A) carrying  cytoplasmic-genetic male sterility, which sheds no viable

      pollen and is maintained by the normal sister strain (B) which is used as pollinator.

 

(d)  The Certified class seed shall be the hybrid seed to be planted for any use except seed production .

 

 

II. Land requirements

      

       Land to be used for seed production of hybrid cotton shall be free of volunteer plants.   

 

III. Field Inspection

 

A. Foundation Seed Production 

 

A minimum of three inspections shall be made, the first and second during flowering and the third at maturity and prior to harvesting.

 

B. Certified Seed Production 

 

    A minimum of four inspections shall be made as follows: 

       

    1. the first inspection shall be made before flowering to verify  isolation, volunteer plants, outcrosses 

       and other relevant factors.

 

    2. the second and third inspections shall be made during flowering to verify isolation, offtypes and 

        other relevant factors.  Incase malesterile line is used for producing hybrid seed, the number fo pollen

        shedding plants in female parent shall also be verified;

 

    3. the fourth inspection shall be made during picking of cotton in female parent in order to determine that 

        selfed bolls are eliminated and only cotton from crossed bolls is picked.  This inspection is not required for the 

        fields if a male sterile line is used. 

    

IV. Field Standards

 

A. General requirements

 

1. Isolation

 

        Seed fields shall be isolated from the contaminants shown in the column 1 of the Table below by the distances specified in columns 2 and 3 of the said Table:


        Contaminants                                                                                   Minimum distance (meters)


                                                                                                                Foundation        Certified


            1                                                                                                         2                     3


Fields of other varieties including commercial 

hybrid of the same variety                                                                               50                   30

 

Fields of the same hybrid (code designation) not conforming to 

varietal purity requirements for certification                                                      50                  30  

 

Fields of other varieties of different spp. (different ploidy levels)                         5                    5   

 

Between blocks of the parental lines incase seed parent

and pollinator are planted in separate blocks                                                    -                      5


 

 

B. Specific requirements


        Factor                                                                                              Maximum permitted (%)*


                                                                                                                Foundation            Certified


        Offtypes                                                                                              0.010                  0.050**

***  Pollen shedding plants in seed parent                                                    0.050                  0.10  


    * Maximum permitted at any inspection at and after flowering.

  ** Standard shall be met separately for seed parent and pollinator.

*** It shall be applicable in case male sterile line is used for the producation of hybrid seed.

   

V. Seed standards

 

    (a) All certified seed lots which have been produced by adopting emasculation shall be subjected to grow-out 

         test and shall conform to the following minimum genetic purity requirements:


                            Class                                                                Genetic purity (%) (minimum)


                        Certified                                                                                90.0%


    *During grow-out test, the offtype plants (other than selfed plants) such as segregants, outcrosses and plants

     of other varieties should not exceed more than 1.50%out of the 10.0% plants earmarked for selfed plants.

 

(b) The minimum population size of 400 plants shall be maintained in two replicates of 200 each or four of 100

     each through out the test and each plant shall be examined individually. The reject number shall be as follow:


                  Class                                                           Genetic purity (%)                Reject number

                                                                                        (minimum)


               Certified                                                            90.0 (10 in 100)                        44


 

                

 


        Factor                                                                                              Standards for each class


                                                                                                                Foundation            Certified


Pure seed (minimum)                                                                                98.0%                    98.0%

Inert matter (maximum)                                                                             2.0%                       2.0%

Other crop seeds (maximum)                                                                    5/ kg                     10 / kg

Weed seeds (maximum)                                                                            5/ kg                     10 / kg

Germination (minimum)                                                                             65%                       65%

Moisture (maximum)                                                                                 10.0%                   10.0%

For vapour-proof containers (maximum)                                                    6.0%                      6.0%


VI. Ginning

    

        Ginning of seed cotton shall be done on the gins approved by the Certification Agency.