Guidelines for Conducting Plant Breeders' Rights Comparative Tests and Trials

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1. Introduction

The purpose of Plant Breeders' Rights (PBR) comparative tests and trials is to determine if the candidate variety is distinct, uniform and stable (DUS). Whereas many countries have a state-run testing system for PBR, Canada has a breeder-run testing system, in which the trials are conducted by the breeder/applicant, agent or someone contracted by the applicant. The Plant Breeders' Rights Office (PBRO) conducts a review of the applicant's data as well as an independent trial examination to verify results. Another important component of the Canadian system is the opportunity for public/peer review of detailed plant descriptions of each variety before rights are granted.

The following is a detailed explanation of the required submissions and the methods to be used for conducting comparative tests and trials which will result in the successful completion of the examination process for applying for Plant Breeders' Rights.

  • a relevant Test Guideline (TG) that has been filled out with appropriate data,
  • a description of the comparative tests and trials, and
  • photographs which clearly demonstrate the characteristics which distinguish the candidate from the reference variety(ies).

These three submissions must be submitted to the PBR within six months of the date on which a PBR examiner conducts the trial examination.

2. Site Examination Request

To initiate the examination process, the applicant must submit a Request for Site Examination form for each candidate variety. The request is due in the PBRO by the beginning of May for examinations required between June 1st and September 30th. For species requiring one growing cycle of comparative tests and trials, the site examination request should be submitted to the PBRO prior to that cycle. For species requiring two growing cycles of comparative tests and trials, the site examination request should be submitted to the PBRO prior to the second growing cycle of trials. Generally, asexually reproduced species require one growing cycle of trials while seed reproduced and woody species require two growing cycles of trials. If the applicant is unsure of the number of years of trials required, he/she may refer to the specific protocols section of the relevant TG for the species in question, or call the PBRO.

In the case of varieties multiplied by seed, for which two years of trials are required, if rights have been granted for these varieties in another member country of the International Union for the Protection of New Varieties of Plants (UPOV), the applicant/agent may arrange to purchase the DUS report from that country through the PBRO. In doing so, the testing requirement in Canada would be reduced from two to one year of trials.

In the case of varieties multiplied by vegetative propagation, for which one year of trials are required, if rights have been granted for these varieties in another member country of UPOV, the applicant/agent may arrange to purchase the DUS report from that country through the PBRO. In doing so, testing in Canada would not be required. For further information see the document Purchasing foreign test results in lieu of conducting tests and trials in Canada.

If trials are conducted in Canada, an examiner from the PBRO must visit the trial site to verify the comparative tests and trials and to see whether or not the candidate variety meets the requirements for distinctness and uniformity. It is the applicant's responsibility to arrange for the examiner's visit at a time when the characteristics being used to distinguish the candidate variety from the reference variety(ies) can be seen. For example, if flower colour is being used as the distinguishing characteristic, then the PBR examiner should visit the trial site when the plants are in full flower. Where several distinguishing characteristics appear at different stages during the growing cycle, the applicant should ensure that the examination will take place when the most important distinguishing characteristic(s) can be viewed.

Please ensure that, as much as possible, the information requested on the PBR Site Examination Request form has been completed. This information enables the PBR examiners to schedule the time of the site examination and speak with the contact person(s) for the trial to coordinate the time of the visit. The PBR Site Examination Request form also provides an outline of what the PBR examiner should expect in terms of the number of candidate and reference varieties involved and the justification for the choice of reference varieties. The reference variety(ies) listed on the request for site examination should be those that will be used at the trial site.

Please note that the candidate variety will not be considered for examination until the following items have been received in the PBRO:

  • the PBR application for filing purposes form (which must be accepted for filing),
  • the examination fee of $750 per candidate variety, and
  • the Site Examination Request form, completed for each candidate variety.

3. Selection of reference Varieties

At the time of application, the applicant/agent must inform the PBRO which reference varieties have been selected. The description of the candidate variety and a comparison of the candidate variety to the reference variety(ies) must be included in the distinctness statement (Section 10C) of the filing requirements on the PBR application for filing purposes form). The selected reference variety(ies) should be varieties of common knowledge. According to the PBR Regulations, section 5, the criteria for determining that a plant variety is a matter of common knowledge are that:

  • the variety is already being cultivated or exploited for commercial purposes, or
  • the variety is described in a publication that is accessible to the public.

The reference varieties should also be of the same species as the candidate variety, must be the most similar morphologically to the candidate variety and grown in Canada at the time of filing the application. If there are other similar foreign variety(ies), these should also be used for comparison. If, for any reason, the choice of reference varieties changes before or at the time the site examination is requested, the applicant/agent must submit to the PBRO, an explanation of the reason(s) for changing the reference varieties. If, at the time the examiner arrives on site to do the examination, the reference varieties are not those listed on the PBR Site Examination Request form, the trials may not be examined.

In selecting reference varieties:

  • Ensure that when they are compared to the candidate, the reference varieties have the same state of expression for as many of the grouping characteristics as possible. Please refer to the specific protocols section of the relevant TG for a list of the applicable grouping characteristics.
  • Where the candidate is the first variety of a species and there are no other known varieties of the same species to compare to the candidate variety, then the wild type or original species of the same genus, regardless of its morphological similarity to the candidate variety, must be used as one of the reference varieties.
  • Where the candidate variety requires registration under the Seeds Act, at least one of the reference varieties must also be a registered variety.
  • Where varieties are being selected for a characteristic such as flower colour, foliage colour, growth habit, plant size, etc., reference varieties should resemble the candidate variety in most, if not all, of the characteristics for which they have been selected by the breeder. For example, if a variety is selected by the breeder as a candidate variety because it produces pink flowers, then, if possible, at least one of the reference varieties should also have pink flowers, not white, yellow, red, etc. Please note that this applies to all other variety characteristics as well.
  • Where varieties are being selected for a combination of characteristics such as growth habit and maturity, for example, reference varieties should resemble the candidate variety in most, if not all, of the characteristics for which they have been selected by the breeder. In such circumstances, it may be necessary to have more than one reference variety; one which is most similar to the candidate variety with regards to maturity and one which is most similar to the candidate variety with regards to growth habit.
  • Where the candidate variety is a genetically modified organism (GMO), then the applicant/agent must ensure that at least one of the reference varieties chosen is the most similar and also contains the same construct, where applicable.
  • Where the candidate variety is the progeny from crosses made by a breeder to develop a product line (e.g. plants developed to have the same plant form and growth habit but variations in the colour of the flowers), those varieties from the product line which are most similar to the candidate variety must be used as reference varieties. Even so, similar varieties outside the product line as well as those from other breeding programs, should be considered as reference varieties.
  • Where other candidate varieties are morphologically similar, they must be grown in comparison to each other as well as to other varieties which are not candidate varieties but are commercially available or of common knowledge at the time the application is filed.

4. Setup of trials

Variety descriptions and observations should be taken from tests and trials that have been set-up or planned specifically for, but not limited to, the purposes of PBR. The tests and trials are to be carried out under conditions ensuring normal growth of the plants being observed. Generally, they should not be comprised of potted plants which have been chosen from production or fields of plants that are in production.

Both the candidate and reference varieties from the comparative tests and trials must be subjected to the same conditions. Only when the candidate and reference varieties are subjected to identical conditions is it possible to reliably compare the two without regard for difference in cultivation. As a result, the differences or distinguishing characteristics observed between the candidate and reference varieties during the examination are the effect of genetic differences between varieties.

In conducting the comparative tests and trials:

  • Both the candidate and reference varieties are to be grown in the same location. This would require that they be grown in the same area of the greenhouse or the same field. In the case of species for which two growing cycles of trials are required, the trials should also, as much as possible, be conducted in the same area of the greenhouse or same field for both growing cycles. Should an objection be filed or rights of a variety be challenged, a grow-out test may be required at this same location.
  • A back-up location in case of extreme weather or other problems resulting in crop failure might be considered for species grown in field trials. For this to be effective, data should be collected at both the primary and back-up locations for all years of the tests.
  • Both the candidate and reference varieties are to be grown in the same size of pots with the same spacing between pots containing the same number of plants or in the same size of field plot planted using the same seeding density.
  • Roguing/removal of plants and/or plant parts which do not conform to the intended description of the variety is not permitted.
  • The minimum numbers of plants for the candidate and reference varieties must be the same. Also, there must be a sufficient number of each to accommodate the requirements indicated in the specific protocols section of the relevant TG. If you are unsure how many plants are required for the PBR site examination, contact the PBR Office.
  • The size of plots or number of plants should be such that plants or plant parts may be removed for measurement and counting, without prejudice to the observations that must be made to the end of the growing cycle. Also, separate plots for observation and measuring can only be used if they have been subjected to the same growing conditions.

5. Test Guideline (TG)

Each TG lists relevant characteristics for specific crop types. The TG is used to describe the candidate and reference varieties and as such, provides documentary evidence of the distinctness of the candidate variety. The TG's are based on technical guidelines accepted by UPOV and used in most other member countries. Breeders and other experts of the species are consulted in the development of each TG. TG's are available from the PBRO. All observations and measurements must be based on the comparative tests and trials performed in Canada. Reference varieties are to be described concurrently using the same characteristics used to describe the candidate variety.

All the required variety characteristics in the TG must be completed for both the candidate and reference varieties. These are highlighted within the body of the TG by an asterisk located beside the characteristic number. If the required characteristics are not completed, the TG will be unacceptable and more information will be requested. If the data for these required variety characteristics can not be provided, an additional year of trials may be required. Completing all of the variety characteristics, whether they are required or not, is beneficial to the applicant/breeder as these characteristics serve to more completely describe the varieties.

If additional information on the distinctness of the candidate variety is available for other variety characteristics which are not found in the TG, this information should be included in the section of the TG for additional characteristics. Also, the submission of molecular test results as supplemental data is acceptable.

When measurements or counts of plants or plant parts are required, the mean (average), the range, the standard deviation and the number of plants or plant parts being measured or counted must be calculated. If any of this information is not provided, the TG will be unacceptable and more information will be requested. If the applicant is unable to provide this data, an additional year of tests and trials may be required. Please note that submission of the raw data collected during the comparative trials to the PBRO office is not necessary, however, it must be retained in case it is requested by an examiner or in the event of an objection.

For varieties that require more than one growing cycle of trials, a TG of the first growing cycle results should be submitted prior to the site examination taking place during the second growing cycle. When the trials for the second growing cycle are completed, the results should be submitted to the PBRO along with a final summary of the two growing cycles of trials combined. Please indicate which growing cycle(s) is/are represented by the trial data in each submitted TG.

6. Description of trials

Information describing the site location(s), the test parameters for the trial (e.g. plot size, planting density of plots, number of replications, number of plants, plant spacing, number of pots per variety, size of pots, number of plants per pot, application of plant growth regulator, etc.) must be submitted with the TG. Please refer to the specific protocols section of the relevant TG to review the test parameters.

7. Comparative photographs

Submission of comparative photographs is a requirement of the examination process. If the applicant/agent submits comparative photographs which do not meet the criteria as described below, they will be given the opportunity to resubmit suitable photographs. If they are unable to do so, publication in the Plant Varieties Journal may be delayed until acceptable photographs are submitted.

The comparative photographs must:

  • Be submitted to the PBRO with the completed TG, to support the tests and trials.
  • Clearly demonstrate that the candidate variety is distinct from the reference variety(ies). For example, if the candidate variety is distinct from the reference variety in plant height, plant width, growth habit, etc., then a photograph of the whole plant may be necessary. However, if the distinguishing characteristics are more specific or related to smaller plant parts, such as flower colour, leaf size, etc., then it would be more appropriate to remove these parts from the plant and take a close-up photograph. For the latter examples, use of a macro lens is recommended. Also the subject of the photographs should occupy as much of the frame of the photograph as possible.
  • Include both the candidate and reference variety(ies) in the same frame of the photograph. If there is more than one reference variety, then all of them should be included in the same frame of the photograph along with the candidate variety. If this is not possible, a common reference measure (e.g. ruler) should be included in each photograph. In situations where the candidate variety differs from one reference variety for one characteristic and also differs from another reference variety for another characteristic, a photograph of each comparison should be submitted.
  • Be based on plant material from the comparative tests and trials conducted in Canada. These could be in the form of actual plants or plant material, a drawing or herbarium specimen of the variety. A photograph of results from biomolecular techniques may be accepted when differences in morphological characteristics are not easily visible.
  • Have the candidate and reference variety(ies) clearly labeled. The candidate variety should be labeled with the proposed denomination. The reference variety(ies) should be labeled with the name by which they were protected (if such is the case) or by the name by which they are known (commercial name).
  • Where suitable, be taken indoors against a grey-neutral background. Photographs taken outdoors should be taken on an overcast day or in light shade, not in full sun.
  • Be submitted in print format and also in jpeg format, if available. The jpeg files can either be submitted on a disc or as an attachment to an E-mail addressed to the PBRO. As much as possible, submit each jpeg file in a 4 x 6 inches (10.15 x 15.24 cm) format.

8. Publication in the Plant Varieties Journal

The PBRO publishes the Plant Varieties Journal. This is a quarterly publication which contains information on applications for PBR. The journal is available on the PBR web-site and provides an opportunity for all interested persons to review the information concerning a variety and to object to the particulars of the published applications if they feel that DUS or other requirements of the PBR Act have not been met.

Following the site examination and submissions of the completed TG, the description of the comparative tests and trials and the comparative photographs, a PBR examiner drafts a description of the candidate variety including a summary of its distinguishing characteristics for publication in the Plant Varieties Journal. This draft of the variety description is sent to the applicant/agent for review prior to publication.

Following the publication of the description there is a six month objection period. If, at the end of this six month period, there are no valid objections to a published variety, the variety becomes eligible for a grant of rights.

If further information is required, please contact the PBRO.

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