Review of UPOV guidelines for the conduct of tests for dus of fruit trees and suggests of developing Chinese Guidelines of Fruit Trees

Abstract: By December 31, 2018, there were 326 UPOV DUS guidelines in total, among which 61 guidelines were for fruit trees. UPOV fruit tree guidelines involved more than 40 genera. In this paper,61 UPOV guidelines for the conduct of tests for DUS of fruit trees were reviewed, and the contents included the subject, release time, main contents, material requirement and test characteristics were summarized and analyzed. The first fruit tree guideline was issued in the 1970 s and it was for Hazelnut. In the 1980 s, UPOV issued two fruit tree guidelines. In the 1990 s it issued seven. But from the year of2000, the number of fruit tree guidelines issued by UPOV increased sharply. There were 29 fruit tree guidelines issued between 2000 and 2009, and the guidelines for pear, apple, grape, et al. were issued in this stage. From 2010 to now, there were already 22 fruit tree guidelines issued. The format and content of UPOV fruit tree guidelines were basically the same. They mainly included 10 parts, which were subject of the test guidelines, material required, method of examination, assessment of distinctness, uniformity and stability, grouping of varieties and organization of the growing trial, introduction to the table of characteristics, table of characteristics, explanations on the table of characteristics, literature and technical questionnaire. The materials required by UPOV fruit tree guidelines mainly were plants, shoots,stem segments, seeds, fruits. Plants were the materials which can be planted directly, including grafted plants, plants on their own roots, rooted cuttings, in vitro plants and potted plants. Shoots were used to propagate plants, including budsticks, dormant shoots, cuttings. Stems were also used to propagate plants, including stem segments, corms and rhizomes. Seeds and fruits were also used to propagate plants. Melon, watermelon, husk tomato, strawberry and prunus rootstocks propagated by seeds needed to submit seeds as the materials. Only coconut needed to submit fruits as the materials. Some guidelines only required one type of these materials, and some require more than two types of these materials, and the corresponding quantity of different types of the materials were also specified. Some guidelines also required different forms and quantities of submissions based on the origin of the cultivar, the reproductive mode of the cultivar, and so on. For example, the guidelines of apple, pear, loquat and mume had different requirements of the number of submissions on the varieties from cross or from mutation. The guidelines of strawberry and Prunus rootstocks had different requirements of the type and number of submissions on the varieties propagated vegetatively or by seeds. Characteristics were the basis of DUS test and examination of plant varieties. Characteristics in UPOV fruit tree guidelines could be divided into standard characteristics, asterisked characteristics, grouping characteristics and technical questionnaire characteristics according to its function. The standard characteristics were those accepted by UPOV in DUS examination and from which UPOV members could select traits suitable for their particular environment. The basic traits of UPOV fruit tree guidelines mainly included characteristics of plants, shoots, buds, leaves, flowers, fruits, seeds, phenological phase, resistance, storage and compatibility. But to rootstock varieties, characteristics of flowers and fruits were not important characteristics,so guidelines for pear rootstocks, prunus rootstocks and avocado rootstocks just had the characteristics of plants, shoots, buds, leaves. The asterisked characteristics were the characteristics that must be adopted in the description of varieties. They were important and necessary characteristics for DUS test.Grouping characteristics are those in which the documented states of expression, even where produced at different locations, can be used, either individually or in combination with other such characteristics to select varieties of common knowledge that can be excluded from the growing trial used for examination of distinctness, and to organize the growing trial so that similar varieties are grouped together.There were one to twelve grouping characteristics in the UPOV fruit tree guidelines, and most of the fruit tree guidelines had three to six grouping characteristics, including characteristics of fruits, phenological phase, plants, shoots, flower and seeds. Technical questionnaire characteristics were characteristics listed in the part of technical questionnaire, they could help to know the basic situation of the variety and to select similar variety through these information provided by breeder. There were two to sixteen technical questionnaire characteristics in the UPOV fruit tree guidelines, and most of the fruit tree guidelines had three to seven technical questionnaire characteristics, including characteristics of fruits,phenological phase, plants, and shoots. DUS test is very important to variety plant protection and variety registration, and test guidelines are the base of DUS test. Many Chinese DUS test guidelines were made on the base of UPOV test guidelines. Through reviewing and analyzing the contents of UPOV fruit tree guidelines, prospect of developing UPOV guidelines and Chinese guidelines of fruit trees were proposed and discussed. The purpose is to provide reference for the development of relevant technical standards in China.