DUS TESTING AND NATIONAL TEST GUIDELINES Dr. A. Sarma National Seed Project (Crops) Assam Agricultural University Jorhat- 785 013

PPV & FR Act 2001 provides protection of new varieties including extant and farmers’ varieties. Novelty, Distinctiveness, Uniformity and Stability are the essential requirements for grant of protection to the varieties.

 “Distinct” means that the variety must be clearly distinguishable by one or more important morphological, physiological or other characteristics from any other variety whose existence is a matter of common knowledge at the time of application.

   “Uniform” means that the variety must be sufficiently uniform or homogenous having regard to the particular features of its sexual reproduction or vegetative propagation.

“ Stable” means that the variety must remain true to its description after repeated reproduction or propagation.

CRITERIA FOR REGISTRATION NEW PLANT VARIETIES - NOVELTY, DISTINCTIVENESS, UNIFORMITY AND STABILITY EXTANT VARIETIES - DISTINCTIVENESS, UNIFORMITY AND STABILITY AS PRESCRIBED

What is DUS Testing? DUS stands for Distinctiveness, Uniformity and Stability. DUS Testing is examination of plant varieties for Distinctiveness, Uniformity and Stability for the purpose of registration of plant varieties under PPV & FR Act 2001

DUS Test Guidelines To set out the principles which are used in examination of DUS, General Guidelines and Specific Guidelines for individual crop species or group of species are required. These represent an agreed and harmonized approach for the examination of new varieties.

Test guidelines have details on following points: Subject Material required Conduct of tests Methods and observations Grouping of varieties Characteristics and symbols Table of characteristics Explanation on the table of characteristics Literature

Subject of the guidelines These test guidelines apply to all varieties of …….. Example: one species (most of the crops) Example: more species (rape seed/mustard etc.) Therefore it is mentioned that: These test guidelines apply to all varieties of wheat (Triticum aestivum) b. These test guidelines apply to all varieties, hybrids and parental lines of rice (Oryza sativa) c. These test guidelines apply to all varieties of rape seed/mustard (Brassica compestris, B. napus, B. juncea)

Material required The Plant Variety Protection (PVP) Authority decides when, where and in what quantity and quality the seed material required for testing the variety is to be delivered. Applicants submitting material from a country other than India must make sure that all customs formalities are complied with. The minimum quantity of seed to be supplied by the applicant, should be: The material is to be supplied in form of …(seed/sets/plants) Quantity of planting material: …………….g Quality standards: The seed should meet the minimum requirements for germination capacity, moisture content and physical purity prescribed for certified seed in India. Especially for storage, which requires a higher standard, the applicant should state, the actual germination capacity which should be as high as possible. contd./

Health status: The plant material supplied should be visibly healthy, not lacking in vigour, nor affected by any important pest or disease Seed treatment: The seed material must not have undergone any treatment unless the competent authorities allow or request such treatment. If it has been treated, full details of the treatment must be given.

Conduct of tests Duration: The minimum duration of tests should normally be two independent similar growing seasons Tests location: The tests should normally be conducted at two locations. If any important characteristic of the variety can not be seen at these places, the variety may be tested at an additional place. Conditions for conducting the examination: The field tests should be carried out under conditions ensuring normal growth. Plant population: Each test should include about …..plants which should be divided among ……replications

Test plot design: The design of the tests should be such that plants or parts of plants may be removed for measurement and counting without prejudice to the observations which must be made up to the end of the growing period Gives details on—i) number of rows ii) row length iii) distance between rows iv) distance between plants v) replications Additional tests: Additional tests, for examining relevant characteristics, may be established  

Grouping of varieties The selection of varieties of common knowledge to be grown in trial with the candidate varieties and the way in which these varieties are divided in groups to facilitate the assessment of distinctness is added by the use of grouping characteristics.

Selection of characteristics: The basic requirement a characteristics should fulfill before it is used for DUS testing are: Results from a given genotype or combination of genotypes. Is sufficiently consistent and repeatable in a particular environment Exhibit sufficient variation between varieties to be able to establish distinctiveness. Is capable of precise definition and recognition. Allows uniformity requirements to be fulfilled. Allows stability requirements to be fulfilled.

Characteristics and symbols 1. To assess distinctness, uniformity and stability, the characteristics and their states as given in the Table of characteristics should be used.  2.   Notes (1 to 9), for the purposes of electronic data processing, are given opposite the states of each characteristic. Explanations are provided about the used in the test guidelines as (*), (+) etc. (*) The characteristics that should be used every growing period for the examinations of all varieties and should always be included in the description of the variety, except when the state of expression of a preceeding characteristic or regional environmental conditions render this impossible.

(+) See Explanations on the Table of characteristics in Chapter VIII The optimum stage of plant growth for assessment of each characteristic is indicated in the sixth column of Table of characteristics.  

Categories of characteristics Grouping characteristics: those in which the documented states of expression, even when produced at different locations , can be used, either individually or in combination with other such characteristics: (a) To select varieties of common knowledge that can be excluded from the growing trial used for examination of distinctness (b) To organize the growing trial so that the similar varieties are grouped together Standard characteristics: those which are approved by authority for development of a variety description Asterisked characteristics (denoted by *): which should always be examined for DUS and included in variety description Additional characteristics: Newly identified characteristics Supportive evidence characteristics: not sufficient on their own to establish distinctiveness but which may provide supporting evidence for other differences

Example of varieties: When appropriate, example varieties are provided to clarify the state of expression of each characteristic Stage of observation: Explains the stage of plant growth when a particular characteristic has to be recorded, like, Submitted seed, seedling, flowering, maturity, harvested seed etc.

Special characteristics Characteristics expressed in response to external factors: disease resistance, chemical resistance Chemical constituents: Chemical constituents Combined characteristics: Characteristics that are expressed separately, but may subsequently be combined

State of expression & corresponding notes: States of expression are given for each characteristic to define the characteristic and to harmonize descriptions. Each state of expression is allocated a corresponding numerical note for ease of recording of data and for the production and exchange of description.

Type of assessment: MG : Measurement by a single observation of a group of plants or parts of plants MS : Measurement of a number of individual plants or parts of plants VG : Visual assessment by a single observation of a group of plants or parts of plants VS : Visual assessment by observation of individual plants or parts of plants

Testing of distinctiveness For measured characteristics as well as visually assessed characteristics statistical methods can be applied.

Grouping characteristics of rice Basal leaf: Sheath colour Time of heading Stem: Length Decorticated grain: Length Decorticated grain: Shape Decorticated grain: Colour Endosperm: Content of amylose Decorticated grain: Aroma

Code Growth stages of rice 10 Emergence of first leaf through coleoptile/second leaf visible 40 Booting 50 1st spikelet of inflorescence just visible 55 ½ of inflorescence emerged 60 Beginning of anthesis 65 Anthesis half way 70 Milk development stage 80 Dough development 90 Ripening 92 Caryopsis hard

S.No. Characteristics State Note Example variety/line Stage of observation Type of assessment 1 2 3 4 5 6 7 1. (+) Coleoptile: Colour Colourless Green Purple Krishna Hamsa, Prasad 10 VS 2. (*) Basalleaf: Sheath colour Light purple Purple lines Uniform purple Rasi,Heera Annada, Bhogali Mahamaya IR 24, Aruna 40 3. Leaf: Intensity of green colour Light Medium Dark Rasi, Vandana Heera, Sugandha VG

Tests for Uniformity A variety is required to be sufficiently uniform, depending on its breeding system, to allow accurate description and assessment of distinctness and to ensure stability. For self-pollinated species up to 1% off-types are normally tolerated in all except cereals. For cereals all the seeds from 100 individual ears are sown in separate rows. Variant ear rows are tolerated up to a maximum of 3 in 100 Contd…

For cross-pollinated crops a variety is sufficiently uniform if the standard deviation for each character examined for distinctness is not repeatedly greater than the pooled standard deviation of the same characters in comparable control varieties, in the same season and test, at a probability of 0.01. For visually assessed characteristics the uniformity of the candidate variety is checked against known comparable varieties.  

Testing of Stability It is not generally possible during a period of 2-3 years to perform test on stability which lead to thee same certainly as the testing of distinctness and homogeneity. Generally, when a submitted sample has been shown to the homogenous during the test, the material can also be considered stable.

  DUS test for hybrids   A company or Breeder seeking protection rights for a hybrid has to submit seed of parental lines and also that of the hybrid for DUS testing. It is essential to test parents of all hybrids, unless one of the parent is a registered variety. Principle for establishment of distinctness of F1 hybrid is that either the F1 should be distinct. or one of the parents should be distinct from parents of non distinct hybrids.

DUS Test Centres Factors to be considered: Where the species can best display its characters; examination at one site may reveal characters which are less obvious at another site; Where there is least risk of damage; the plots can be at risk from pests, diseases and the weather;   Where there is link with the region and the characters will be expressed most clearly Where there is breeders’ access; breeders like to see how their varieties are performing in the test and to discuss any problems with the testing authority staff.

THANK YOU