两系杂交水稻种子生产体系技术规范第 5 部分 : 种子纯度鉴定和不育系育性监测技术规范

Transcription

1 Translated English of Chinese Standard: GB/T Translated by: Wayne Zheng et al. ICS GB B 21 NATIONAL STANDARD OF THE PEOPLE S REPUBLIC OF CHINA GB/T Technical rules for seed production system of two-line hybrid rice - Part 5: Technical rules for identification of variety purity & male sterility of MS line 两系杂交水稻种子生产体系技术规范第 5 部分 : 种子纯度鉴定和不育系育性监测技术规范 Issued on: December 31, 2012 Implemented on: July 1, 2013 Issued by: General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration Committee of the People's Republic of China. Page 1 of 10

2 Table of Contents Foreword Scope Normative references Fertility monitoring of sterile line Identification of seed purity planting Page 2 of 10

3 Foreword GB/T Technical rules for seed producing system of two-line hybrid rice consists of five parts, as follows: Part 1: Terminology; Part 2: Technical rules for foundation seed production of photo/thermo-sensitive genic male sterile line; Part 3: Technical rules for seed multiplication of photo/thermo-sensitive genic male sterile line; Part 4: Technical rules for F1 seed production; Part 5: Technical rules for identification of variety purity & male sterility of MS line. This is Part 5 of GB/T This Part is drafted according to the rules specified in GB/T This Part was proposed by Ministry of Agriculture of the People s Republic of China. This Part shall be under the jurisdiction of National Technical Committee (SAC/TC 37) on Crop Seed of Standardization Administration of China. The responsible drafting organizations: Hunan Hybrid Rice Research Center, Hunan Longping Seed Industry Co., Ltd, Hunan Agricultural University, Hunan Seed Administration, Anhui Academy of Agriculture, Jiangsu Academy of Agriculture, and Guangdong Academy of Agriculture. The chief drafting staffs of this standard: Zhou Chengshuo, Liu Aimin, Li Wenxiang, Xiao Cenglin, Wang Shouhai, Lyu Chuangen, Wang Feng, Liao Cuimeng, Liu Jianbing, and Ouyang Aihui. Page 3 of 10

4 Technical rules for seed production system of two-line hybrid rice Part 5: Technical rules for identification of variety purity & male sterility of MS line 1 Scope This Part of GB/T specifies the methods and procedures for monitoring the critical temperature for inducing male sterility of the photo/thermo-sensitive genic male sterile line of rice of the high temperature inducing male sterility line, and identifying the purity of male sterile seeds and hybrid seeds planting. This Part is applicable to monitoring of the determined or identified critical temperature for inducing male sterility of photo/thermo-sensitive genic male sterile line of the high temperature inducing male sterility line, and identification of the purity of male sterile seeds and hybrid seeds planting. 2 Normative references The articles contained in the following documents have become part of this standard when they are quoted herein. For the dated documents so quoted, all the modifications (Including all corrections) or revisions made thereafter shall be applicable to this Standard. GB GB/T Seed of food crops - Part 1: Cereals Rules for agricultural seed testing-sampling 3 Fertility monitoring of sterile line 3.1 Monitoring of phytotron Monitoring materials and requirements Monitoring materials The photo/thermo-sensitive genic male sterile line of rice that passes the examination or technical identification by the provincial or above-level Crop Variety Approval Committee, and being used in production Material requirements Identification materials require 300g-500g of seeds; germination rate 80%; and purity 99.5%. And provide the breed standard when the sterile line passed the approval or identification Sampling requirements It shall execute the provisions of GB/T Page 4 of 10

5 sterile line for identification). See Table 1 for temperature of each period. Table 1 Temperature and light setting in phytotron with daily average temperature of 23.5 C or 23.0 C Temperature Daily average Daily average Time temperature temperature Sunshine 23.5 C 23.0 C 06: 01-10: C 23.0 C Light intensity lx 10: 01-18: C 26.0 C 20:00-6:00 is deemed as dark period (14.0h) 18: 01-22: C 23.0 C 19:30-6:00 is deemed as dark period (13.5h) 22: 01-06: C 20.0 C 18:30-6:00 is deemed as dark period (12.5h) Temperature and light setting during transitional period 2d before and after the processing, if the natural daily average temperature is 30 C or 25 C, then the processing materials shall be transited for 2d under the conditions day-time temperature of 28 C, night-time temperature of 24 C, and light intensity of lx, and then move them into the phytotron or place them in a natural conditions Fertility observation Observed object When the process in phytotron is completed, tag and mark the rice spikes of which the distance between flag-leaf and top-second leaf is 0 cm - 2 cm Observation method When the marked spikes grow into the initial heading stage, every morning take the glumous flowers that will be flowering on that day (anthers length stretching to two-thirds of glumous flower) to conduct pollen observation under microscope. Randomly pick 5-6 glumous flowers from each ear; their anther is made into 1 observing piece. Use I2-KI solution to dye the pollens and press into piece. Under the optical microscope, amplify 100 times to inspect. Choose 3 representative views for each piece. Pollen particles of each view shall be more than 50. Observe and count the numbers of different type of pollens of 3 views (non-pollen abortion type, typical abortion type, spherical abortion type, stained abortion type, and normal). Calculate the percentage of different type of pollens in each piece. If stained pollen is found in an observation piece, then it is deemed as male sterility alteration Times of observations Observation under microscope shall be conducted once a day, until the marked spikes end the flowering Pollen classification Page 6 of 10

6 3.2.4 Fertility examination Pollen observation under microscope From the beginning of flowering to the latest normal heading, observation under microscope shall be conducted once every 2d-3d. If there are staining pollens found during this period, the pollen observation under microscope shall be conducted every day, from that day until two days after the day without staining pollens Examination of self-seeding rate Randomly select 10 single-plants from the seeding period when staining pollens are found in observation under microscope. Completely isolate them to cultivate. 20d-25d after full heading, examine the self-seed rate Investigation for sterile line group uniformity Select two completely sterile seeding periods for each sterile line. Investigate the growth period, plant height, plant leaf and ear grain type, color, and other characters Comprehensive evaluation Agronomic characters According to the monitored materials field s fertile property, plant morphological characteristic, ear grain shape, outcross characteristics, resistance, and other performances, evaluate the stability and conformity of monitored materials group, in combination with breed introduction Critical temperature for inducing male sterility Correspondingly analyze the daily average temperature BETWEEN the date occurred in fertility alteration AND fertility sensitive period of each natural ecological point. Judge the sterility critical temperature of monitored materials. 4 Identification of seed purity planting 4.1 Identification materials They are sterile line seeds and hybrid seeds. 4.2 Identification procedures Take samples According to the related provisions of GB/T Field selection Page 8 of 10

7 Field management Select the field of medium soil-fertility as the planting identification field. And use lower fertilizer level management. Pay attention to the pest control, snail control, and rat control in growth period Identification Identification period Identification shall be conducted in the period of obvious characteristics. The heading and flowering period and maturation period shall be identified Identity for breed authenticity According to the character description of control samples and identification breeds, identity the breed authenticity of samples Determination for hybrid strains type Hybrid strains type of sterile line breeds include isomorphic fertile strains, special strains, precocious strains, late maturing strains, and other hybrid strains. Hybrid strains type of hybrid seeds include sterile line strains, isomorphic fertile strains, different-variety strains, male-parent stains, and other hybrid strains. 4.3 Result calculation and judgment Result calculation The seed purity is expressed by the percentage of standard breed plants TO the identification total plants. Keep one decimal place Quality determination The quality of breed purity shall be executed according to the relevant provisions of GB END Page 10 of 10