Experts warn: Be on alert for a resurgence of wheat stripe rust in 2021.

Release Date:

2021-01-04

Recently, a reporter learned from the Shaanxi Plant Protection Station that, as of December 14, wheat stripe rust had broken out across 30 counties and county-level districts in six cities—Baoji, Xianyang, Xi’an, Weinan, Hanzhong, and Ankang—covering an area of 710,500 mu. This marks the year with the highest number of affected counties and the largest total infected area in the past decade (since 2010).

According to analysis, compared with the same period in 2019—when 522,900 mu were affected across 22 counties and county-level districts in five cities—the current year sees an additional 187,600 mu in one city and eight counties and county-level districts. Moreover, this represents a rise of 630,500 mu across 23 counties and county-level districts, up from the 2010–2019 average of 180,000 mu in seven counties and county-level districts. This year, the number of counties reporting wheat stripe rust, the affected area, and the severity of the disease are all greater than last year and higher than the long-term average for this time of year, indicating that the pathogen inoculum has reached levels sufficient to trigger a major outbreak. Local authorities should continue to strengthen monitoring, promptly track disease dynamics, tailor measures to local conditions, provide site-specific guidance, and curb the spread of stripe rust.

Why has stripe rust been so severe this year? Professor Wang Baotong of the College of Plant Protection at Northwest A&F University outlined five key reasons for the early‑season infection in autumn seedlings. First, the initial pathogen inoculum was substantial. In Gansu Province, a major reservoir for wheat stripe rust, the 2019 autumn seedling inoculum was abundant, creating conditions that allowed sufficient pathogen dispersal into eastern wheat-growing regions and providing a large overwintering source for stripe rust in Shaanxi’s Guanzhong Plain winter wheat. Second, cultivar resistance is weak, particularly among the dominant varieties, which are susceptible during the seedling stage. With the continuous emergence of new virulent races of the stripe rust pathogen, most of Shaanxi’s principal wheat varieties have lost their resistance; only a few exhibit some level of resistance at the adult plant stage, thereby facilitating widespread infection in autumn seedlings. Third, meteorological conditions were favorable: rainfall across the province was above average around the time of autumn sowing, soil moisture remained adequate, field humidity stayed high during autumn and winter, and morning and evening leaf dew formation was normal—conditions conducive to the onset and spread of stripe rust on autumn seedlings. Fourth, autumn seedlings were excessively dense and vigorous. During the autumn sowing period, northern counties such as Baoji and Xianyang in the Guanzhong Plain planted wheat 7–10 days earlier than usual, with higher seeding rates. Consequently, many fields exhibited overly dense stands; combined with high field humidity and relatively warm temperatures, these factors promoted repeated infections, rapid multiplication, and extensive dissemination of the pathogen. Fifth, seed‑treatment practices were inadequate: emphasis was placed on insecticides while fungicide application was neglected. Although Shaanxi vigorously promoted chemical seed treatments during this year’s autumn sowing, in practice most areas applied insecticides only to control underground pests, overlooking the use of fungicides—another significant factor contributing to the severity of autumn seedling infections in the province.

In response to the severe and widespread incidence of wheat diseases during this year’s autumn seedling stage, it is recommended that the Shaanxi Provincial Plant Protection Department closely monitor disease dynamics in winter fields through a combination of fixed-point observations and nationwide surveys, ensuring timely tracking of disease progression. Particular attention should be paid to the impact of winter temperatures on field disease development. In early spring 2021, conduct early monitoring of designated observation plots to promptly assess the overwintering inoculum levels, thereby providing first-hand data for the prevention and control of wheat stripe rust in the spring.

Source: Agricultural Science and Technology News

Tags:

2021 Global Pesticide Industry Development Trend Forecast: Outsourcing of Intermediates and Active Pharmaceutical Ingredients Is a Key Driver of Global Industrial Relocation.

The Ministry of Ecology and Environment provides an interpretation of the newly formulated “Emission Standard for Air Pollutants from the Pesticide Manufacturing Industry.”

More information

The National Agricultural Technology Center has issued guidelines on “one spray, three protections” for wheat to address the heightened risk of recurrent outbreaks of Fusarium head blight, stripe rust, and aphids.

2026-04-10

The petrochemical and chemical industries comprise more than 27,000 large-scale production enterprises—efforts to upgrade and retrofit aging facilities are being further intensified.

2026-04-06

In 2026, corn borer, cotton bollworm, and ear rot—among other corn pests and diseases—are expected to occur at a relatively severe level. The National Agricultural Technology Center has issued a control plan!

2026-04-02

Address: