Tree seeding quality grading of major species for afforestation
GB 6000-1999 replaces GB 6000-1985
Implementation date: April 1, 2000
In order to adapt to the development of seedling production technology in China, GB 6000-1985 "seedlings of main afforestation tree species" is revised. The revised standard retains the content of the original standard which has been proved to be in line with the seedling production and afforestation seedlings in China. The relevant contents of the original standard are modified as follows:
19 tree species were added and 11 species were removed, and some quality indexes which were not in line with the current production were modified appropriately;
Increasing the length of root, the number of lateral roots greater than 5 cm or the width of roots were regarded as the indexes of seedling quality grading;
The quality grade of seedlings is no longer listed as grade III (unqualified seedlings), but a two-level system is adopted, and only grade I and II seedlings (qualified seedlings) are determined;
Other important morphological and physiological indexes affecting seedling quality were added as comprehensive control conditions;
The number of new root growth points (TNR) index was added to test the vitality of conifer seedlings after long-term storage;
The indexes of seedling yield and density were removed.
This standard replaces GB 6000-1095 from the date of implementation.
Appendix A of this standard is the appendix of the standard.
This standard is proposed by the State Forestry Administration.
This standard is under the jurisdiction of the national forest seed Standardization Technical Committee.
This standard is drafted by Beijing Forestry University, Heilongjiang Academy of Forestry Sciences, Nanjing Forestry University, Guangxi Academy of Forestry Sciences, Sichuan Forestry Department, Sanbei Bureau of State Forestry Administration and Yangpu general station of State Forestry Administration.
The drafting units of this standard include: Seedling Station of Beijing Forestry Bureau, seedling station of Liaoning forestry department, seedling station of Shandong Forestry Department, seedling station of Shanxi forestry department, seedling station of Gansu Provincial Forestry Department, seedling station of Inner Mongolia Forestry Department, seedling station of Hunan forestry department, seedling station of Fujian Forestry Department, seedling station of Forestry Department of Guangxi Zhuang Autonomous Region, forest seedling station of Yunnan Province Seedling station of Forestry Department of Zhejiang Province and Forestry Bureau of Daxinganling Forestry Company.
Main drafters of this standard: Song Tingmao, Liu Yong, Jin Tieshan, Yu yuanroll, Miao Meiqin, Wang Xiuqin, Li Changfa, Zhou Jingli.
Quality classification of main afforestation tree species Viburnum chinense
This standard specifies the definition, classification requirements, inspection methods and inspection rules of seedlings of main afforestation tree species.
This standard is applicable to bare root seedlings cultivated in open field for afforestation, but not for container seedlings and seedlings cultivated in greenhouse.
The following definitions are adopted in this standard.
2.1 stock type
According to the propagation materials and cultivation methods, the seedling groups are divided into sowing seedlings, cutting seedlings, root cutting seedlings, transplanting seedlings, grafting seedlings, etc.
2.2 stock age
The age of the seedlings. From sowing, cutting or burying roots to nursery, the actual growth age of seedlings. One year growth cycle was taken as a seedling age unit.
The age of seedlings is expressed by Arabic numerals, and the first number represents the age of seeding seedlings or vegetative propagation seedlings in situ; The second number represents the number of years of incubation after the first transplantation; The third number indicates the number of years of cultivation after the second transplantation. The numbers are separated by short horizontal lines. The sum of the numbers is the age of the seedlings, which is called several years old. For example:
- 1-0 means 1-year-old seedlings without transplanting.
- 2-0 means 2-year-old seedlings without transplanting.
- 2-2 means 4-year-old transplanted seedlings, transplanted once, and continued to cultivate for two years after transplantation.
- 2-2-2 means 6-year-old seedlings were transplanted twice and cultivated for two years after each transplantation.
- 0.2-0.8 means 1-year-old seedlings are transplanted once, two tenths of a year's growth cycle, and eight tenths of a year after transplantation.
- 0.5-0 refers to the half year-old seedlings, which have not been transplanted and completed the half year growth cycle.
- 1 (2) - 0 refers to cuttings, skid roots or grafted seedlings without transplanting for one year and two years.
- 1 (2) - 1 refers to cuttings, roots or grafted seedlings transplanted once every 2 years and 3 years.
Note: the numbers in brackets indicate the age of cuttings, rhizobacteria or grafted seedlings in situ (bed, ridge).
2.3 a lot of seeds
The same age seedlings of the same tree species in the same nursery, with the same batch of breeding materials and basically the same seedling technology, are called a batch of seedlings (referred to as seedling batch).
2.4 ground diameter caliper
The ground diameter of seedlings is the thickness of soil trace at the base of seedling trunk; Cuttings and root cuttings are germinating seedlings, which are the coarseness at the base of germination trunk; The grafted seedlings were the diameter of the normal diameter above the interface.
2.5 seedling height
The length of stem from ground diameter to base of terminal bud.
2.6 root length and width
The length and width of the root system should be retained after the seedling is raised and roots are pruned.
two point seven First degree lateral root
Lateral roots growing directly from the taproot.
2.8 total number of new roots
The number of new root growth points counted after the seedlings were planted in the suitable environment for a certain period of time, referred to as TNR.
3 classification requirements
3.1 see Appendix A (standard appendix) for seedling grade.
3.2 qualified seedlings are determined by comprehensive control conditions, root system, ground diameter and seedling height.
3.3 if the comprehensive control conditions fail to meet the requirements, the seedlings will be classified according to the three indexes of root system, ground diameter and seedling height.
3.4 the comprehensive control conditions are as follows: there are no quarantine object diseases and insect pests, the seedlings are straight, the color is normal, and the sprouting ability is weak. The top buds of coniferous trees are full and strong, fully lignified and without mechanical damage. For coniferous seedlings stored for a long time, the TNR of the seedlings should be measured 10-15 days before the nursery, and the TNR value should meet the requirements of the corresponding tree species in Appendix A.
3.5 when grading, first look at the root index, and determine the seedling grade according to the level reached by the root system. If the root system meets the requirements of class I seedling, the seedling can be grade I or grade II. If the root system only meets the requirements of class II seedling, the highest seedling is only grade II. After the root system meets the requirements, it is classified according to the ground diameter and seedling height index. If the root system fails to meet the requirements, it is unqualified.
3.6 the qualified seedlings are divided into two grades I and II, which are determined by the ground diameter and seedling height. When the seedling height and ground diameter are not in the same level, the ground diameter level shall prevail.
3.7 the grading of seedlings must be in the shade of north wind, and grade marks should be made after grading.
Appendix A (appendix of the standard) seedling quality grade table