GB/T 15796-2026Technical specification for the monitoring and forecasting of wheat head blight (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part

1.Structure and Drafting Rules of Standardization Documents". Drafting. This document replaces GB/T 15796-2011 "Technical Specification for Monitoring and Forecasting of Wheat Fusarium Head Blight". Compared with GB/T 15796-2011, except for the structure... Aside from adjustments and editorial changes, the main technical changes are as follows:

a) Added classification or calculation methods for survey items (see Chapter 4);

b) The relevant content and reporting forms for the bacterial source baseline survey have been revised (see Chapter 5 and Table A.1, Chapter 4 and Table A.1 of the.2011 edition). Table A.2);

c) The content related to aerial ascospore capture has been deleted (see

4.3 in the.2011 edition);

d) The relevant content of the disease survey has been modified, merging "Systematic Disease Survey" and "General Disease Survey" into "Dynamic Disease Survey" and streamlining it. Related content (see Chapter 6, Chapters 5 and 6 of the.2011 edition);

e) The grading index for the severity of wheat scab occurrence has been changed, and the upper limits for levels 1, 2, and 3 have been lowered (see Chapter 7,.2011 edition). Chapter 3);

f) Added content related to using smart devices for disease prediction (see 8.4);

g) Added relevant content regarding the reporting of wheat scab monitoring information (see 9.3);

h) The wheat scab model report and damage estimation model have been removed (see Appendix D of the.2011 edition). Please note that some content in this document may involve patents. The issuing organization of this document assumes no responsibility for identifying patents. This document was proposed and is under the jurisdiction of the Ministry of Agriculture and Rural Affairs of the People's Republic of China. This document was drafted by: National Agricultural Technology Extension Service Center, Jiangsu Provincial Plant Protection and Quarantine Station, and Henan Provincial Plant Protection and Quarantine Station. Station, Hubei Provincial Plant Protection Station, Shaanxi Provincial Plant Protection Station. The main drafters of this document are. Zeng Juan, Bian Yue, Jiang Yuying, Liu Jie, Zhang Haibo, Peng Hong, Yang Junjie, and Xie Feizhou. The release history of this document and the document it replaces is as follows:

---First published in.1995 as GB/T 15796-1995, and revised for the first time in.2011;

---This is the second revision. Technical Specifications for Monitoring and Forecasting of Wheat Fusarium Head Blight

1 Scope

GB/T 15796-2026 is the Chinese national standard covering forecasting fusarium head blight - a disease that infects wheat during flowering if it rains, and that leaves mycotoxins in the grain, so the forecast has to be made from the weather in a window of a few days. The forecast decides whether a province sprays millions of hectares. It replaces GB/T 15796-2011 and has been in force since 1 October 2026. It was issued on 31 March 2026 and takes effect on 1 October 2026, replacing GB/T 15796-2011. The document is under the responsibility of the Ministry of Agriculture and Rural Affairs. This page is published from the official record of the 2026 edition; the clause text of a standard this recent is not yet in circulation, and the figures, limits and tables it contains are those of the document itself, delivered in full with the English translation.

This document specifies the requirements for the investigation, forecasting, data recording, summarization, and reporting of wheat scab, and describes the corresponding verification methods. This document is applicable to the investigation and prediction of wheat scab disease.

4 Classification or calculation methods for survey items

4.1 Carrier rate of diseased and disabled individuals The bacterial carriage rate of diseased plant debris is expressed as the percentage of diseased plant debris clusters (strains) producing ascocarps to the total number of clusters (strains) surveyed, and is calculated according to formula (1). Calculate the weighted average bacterial carriage rate of ascocarp in diseased and damaged tissues.

4.2 Ascocarp maturity Indoor microscopic examination of diseased perithecia was used to grade the specimens based on the maturity of most spores within the microscope's field of view, resulting in four grades.

0.Periothecia are formed, but no asci or ascospores are present;

1.Ascocarp stage, when crushed, only club-shaped and chrysanthemum-shaped clusters of asci are visible, and no ascospores are seen;

2.Ascospore stage, with clear septa of ascospores, or distinctly identifiable ascospores within the asci;

3.Ascospore release stage. The ascocarps are large and fragile, containing a large number of ascospores. The surface of the ascocarps is often gray or pink. Colored powder.

4.3 Ascocarp Maturity Index Calculate according to formula (2).

5 Investigation of the initial bacterial count

5.1 Survey period The survey should be conducted once each during the wheat jointing and booting stages, and the survey time should be roughly the same for each year in the same region.

5.2 Survey Fields In rice-wheat rotation areas, three areas with remaining rice stubble were selected, and three plots were surveyed at each location; in dryland farming areas, areas with remaining corn and wheat straw were selected. Three areas with diseased or damaged ears of wheat were selected, and three plots were surveyed at each location. The selected plots should be representative, and the area of this type of field in the local wheat fields should be estimated. Product ratio.

6 Disease progression survey

6.1 Survey period Surveys were conducted every 7 days from the beginning of the heading stage until the waxy ripening stage. The waxy ripening stage survey was a fixed-location survey.

6.2 Survey Fields Based on the type of previous crop (rice or dryland), wheat variety, and growth period, select no fewer than 10 plots of various types. Main types A control field should be set up in the field, and no fungicide should be sprayed during the growing season.

6.3 Survey Methodology Five random sampling points were taken from each field, with 100-200 ears of grain surveyed at each point. The number of diseased ears was counted, and the diseased ear rate and diseased field rate were calculated. The survey was conducted strictly at the time of field determination. For severe cases, calculate the disease index and estimate the granulation rate based on the severity. Record the data according to Table A.2.

7.Occurrence severity grading index The severity of wheat scab is classified into five levels. mild (Level 1), moderately mild (Level 2), moderately severe (Level 3), and severely severe (Level 4). (Level 4) and (Level 5) outbreaks are determined primarily by the average diseased ear rate from local surveys and by referencing the percentage of diseased area. See details... Table 1.

8 Forecasting and Prediction

8.1 Long-term forecast One month before wheat heading, based on the current year's disease and plant debris infection rate, wheat variety resistance, growth period, and growth vigor are compared with the forecasts from March to May. Rainfall and temperature, as well as irrigation conditions in wheat-growing areas such as North China and Northwest China, were considered. A comprehensive analysis, conducted through expert consultation, determined the extent of Fusarium head blight occurrence that year. And the prediction of the area to be affected.

8.2 Medium-term forecast Before wheat heading, the severity and extent of Fusarium head blight occurrence are assessed based on wheat variety resistance, the timing of heading and flowering, and the degree of coincidence with consecutive rainy days. For the prediction of wheat accumulation, irrigation methods, timing, and frequency should also be considered in wheat-growing areas such as North China and Northwest China. The prediction results should be reported according to Table A.4.

8.3 Short-term forecast During the wheat heading stage, 3 to 10 days before the Fusarium head blight control campaign (or 5 to 7 days before large-scale wheat heading), based on the perithecia maturity index, The progress of wheat heading and flowering, the temperature during the heading and flowering period, and the duration of continuous rainy days (or irrigation duration) were predicted using locally applicable mathematical statistics. The model can predict the extent and area of Fusarium head blight.

8.4 Intelligent Equipment Prediction Using intelligent forecasting equipment for epidemic diseases, disease epidemic parameters are collected to generate continuously updated data on the incidence, disease incidence rate, and control measures for Fusarium head blight. Timely forecasting.