Embrapa, Bayer to Map Mechanism of Soybean Disease Resistance to Fungicides

Soybean rust; credit: Mauricio Meyer

The Brazilian Agricultural Research Corporation (Embrapa) and Bayer have established a partnership to study the mechanisms that cause soybean pathogenic fungi to lose sensitivity to the products currently used in the fields.

Estimated to last five years, the research project aims to identify the fungi Corynespora cassiicola (which causes target spot) and Phakopsora pachyrhizi (responsible for Asian soybean rust) resistance to the fungicides available in the market. “We want to understand how and where resistance occurs in such fungi, and thus adopt anti-resistance preventive actions”, Embrapa Soybean researcher Maurício Meyer explains.

One of the main goals of the partnership is to participate in the effort of sequencing the genome of the Asian soybean rust fungus, which is being led by an international consortium that comprises Embrapa, Bayer, and other research institutions from Germany, France and the United States. Based on the data generated by the P. pachyrhizi genome sequencing, the project is going to unfold in two research fronts.

On one hand, the research wants to understand the fungus’ gene mutation mechanisms that provoke loss of sensitivity and resistance to the main groups of fungicides used to control the disease. In the other study section, the idea is to identify regions of the fungus’ genome associated with its plant virulence, and the results could help the development of Asian soybean rust-resistant varieties.

“We will have five years to better understand the mechanisms of resistance to fungicides through the genetic mapping of the fungi. With the genome in hand, we will be able to understand how loss of sensitivity occurs, anticipate anti-resistance management strategies, and develop more efficient solutions for control”, explains the Bayer’s Advanced Fungicide Development manager, Rogério Bortolan.

The genetic sequencing of P. pachyrhizi is a major challenge to be tacked by the project, considering the size and the complexity of its genome. At least one previous attempt to sequence and assemble the fungal genome has failed. “However, in order to advance in the development of new tools for Asian rust control, the sequencing is fundamental,” Meyer stresses.

The study will be based on a standard sample of the fungus that has possibly suffered few mutations as it was not exposed to many successive fungicide applications. Then there will be a resequencing of isolates (parts of the fungus’ genome) collected in Brazil and in other countries throughout the last decade that have different profiles of virulence and sensitivity to fungicides, due to their constant contact with such products.

“By obtaining the fungus’ reference genome followed by the resequencing of different isolates, we hope to decipher its biology and to understand the complex interaction with host plants, and also broaden our understanding of its adaptability, evolution and genetic diversity,” explains the researcher from Embrapa Soybean Francismar Marcelino. The results obtained will be published and will benefit the entire soybean production chain.

The project also intends to study the changes that occurred to the C. cassiicola and P. pachyrhizi fungi due to their exposure to different groups of fungicides. For that purpose, the fungi’s sensitivity will be compared by opposing populations that suffered no or low amounts of genetic mutations to those that suffered selection pressure from larger exposure to the fungicides applied to the crop in the course of the last 10 years. “Then we will have parameters to identify and monitor the development of resistance to fungicides, and to verify whether new mutations are taking place,” Meyer says.

The last stage of the study includes the mapping of Brazilian soybean producing areas at potential risk of developing resistance to fungicides. “If the study identifies that the frequency of fungal genetic mutations increased a lot in a given region, that is an indicator that the pressure for that group of fungicides is higher in the region at stake. It will be a warning sign to anticipate the adoption of anti-resistance measures and prevent the loss in product efficiency,” he says. The need to change the chemical control strategy in light of the reality of each region is a way to preserve fungicides, since there are low prospects of launching new products in the market in the upcoming years.

According to the head of Agronomic Development at Bayer, Bernard Jacqmin, the study paves the way towards solving a great challenge of the industry: ensuring the sustainability of existing tools for soybean disease control. “Such cooperation with Embrapa will be essential to further the study of fungal genetics and the understanding of how resistance develops after repeated fungicide applications. The resort to an institution like Embrapa provides Bayer with backing to present the recommendations derived from the research to the sector and to farmers, especially at the time of implementing them in the fields”, he concludes.

Understanding soybean rust

Asian soybean rust, the most severe disease for the crop, was identified in Brazil in the 2001/2002 harvest. The disease causes early defoliation, and compromises the formation and development of the pods and of the final grain weight. Hence it can damage up to 100% of the yield if it is not adequately managed. The average rust cost (expenses with fungicides for control + production losses) is $2 billion per harvest in Brazil.

The disease control has focused mainly on chemical control. Despite the contribution from three groups of fungicides in the market, the Antirust Consortium has observed a reduction in the efficiency of these products since the 2007/2008 harvest, due to the increased frequency of mutations that reduce the efficiency of control. The fungi’s resistance to fungicides is a natural process. Nevertheless, the shelf life of the chemical products can be extended with their rational use, anti-resistance strategies and the adoption of best practices.

Topics: , ,

Agrichemicals

Agrichemicals

BASF Agricultural Solutions Quarterly Sales Jump 10%

BASF’s Agricultural Solutions business posted a 10% in quarterly sales on higher volumes. In the Agricultural Solutions segment, sales in

Agrichemicals

Overview of the Indian Crop Protection Market

Agriculture is the backbone of Indian economy with 52% of the population engaged in agriculture and related activities. But the

Flag of China
Agrichemicals

Top 10 Glyphosate Exporters in China for 2016

Fuhua Tongda was the biggest exporter of glyphosate in China in 2016.

Agrichemicals

Syngenta’s Minecto Pro Insecticide Approved by EPA

Minecto Pro insecticide approved for use in specialty and vegetable crops to control lepidopteran pests as well as sucking/rasping/chewing pests.

Adjuvants

Before a New Weed-Control Era Begins, One Last Obstacle

Adjuvant companies anxious for tank-mixing approvals with D-traited technologies as application season closes in.

Agrichemicals

Mitsui Acquires 10% Stake in Belchim Crop Protection

The companies cited lengthy development cycles, increased regulatory demands and costs and market changes for intensifying their cooperation.

Adjuvants

Oxiteno Expands Business in the U.S., to Construct Plant

Oxiteno appointed Timothy Earl Madden as COO of Oxiteno USA.

Africa/Middle East

Syngenta Sales Boosted by Strength in Europe, Africa and Middle East

The company expects its pending merger with ChemChina to close in the second quarter of 2017.

Agrichemicals

Arysta, DuPont to Develop New Insecticides Based on Rynaxypyr

The long-term agreement between the two companies allows Arysta LifeScience to combine Rynaxypyr insect control in premixes with acetamiprid.

Agrichemicals

Just ‘Okay’ Isn’t Good Enough with Dicamba Cropping Systems

Thus far, crop protection product experts have a very simple message for custom applicators who plan to use the new dicamba herbicides in their operations for 2017 – follow the label, or else!

nufarm logo
Agrichemicals

Nufarm Launches New Seed Treatment Solutions

The new products include three new Spirato seed treatments, Sativa IMF Sembolite MAX, and Salient 372 FS.

Agrichemicals

FMC Ag Solutions Profit Rises in Fourth Quarter

Profit boosted by strong pricing in Latin America despite the strengthening of the U.S. dollar.

Agrichemicals

Stockton’s ‘Hybrid’ Conventional/Bio Fungicide Registered in Israel

REGEV, its first ever hybrid fungicide, obtained registration from the Ministry of Agriculture in Israel for the control of fungal plant diseases.

Agrichemicals

Arysta LifeScience Receives EPA Approval on Two In-Furrow Products

TEPERA brand fungicides will help corn, soybean plants get an early, healthy start.

Agrichemicals

Slower to Pull the Trigger on Fungicides, U.S. Growers Asking More Questions

"Growers will try to do some scouting and decision-making on whether they really need that product or not based on probability of return.” -Damon Smith, University of Wisconsin

Agrichemicals

India’s Registration Committee Adopts New Rules for Import and Manufacturing

The Registration Committee considered the governments “Make in India” agenda while deliberating issues and suggesting various changes to the rules

Agrichemicals

Opinion: Trump’s Trans-Pacific Partnership Decision a Head Scratcher

Editor’s Note: Matthew J. Grassi is Field Editor with CropLife® magazine a sister publication to AgriBusiness Global. Matthew can be reached

Agrichemicals

BASF Enters Indian Crop Protection Market for Rice

Range of new solutions to boost rice yields in India by managing diseases, weeds and pests.

Africa/Middle East

An Invitation to Be Rewarded for Environmental Excellence

Dear Crop Protection Professional, As an AgriBusiness Global™ reader, you’re no doubt aware we organize the Environmental Respect Awards each

Latest News

Agrichemicals

BASF Agricultural Solutions Quarterly Sales Jump 10%

BASF’s Agricultural Solutions business posted a 10% in quarterly sales on higher volumes. In the Agricultural Solutions segment, sales in

Agrichemicals

Overview of the Indian Crop Protection Market

Agriculture is the backbone of Indian economy with 52% of the population engaged in agriculture and related activities. But the

Agrichemicals

Top 10 Glyphosate Exporters in China for 2016

Fuhua Tongda was the biggest exporter of glyphosate in China in 2016.

Agrichemicals

Syngenta’s Minecto Pro Insecticide Approved by EPA

Minecto Pro insecticide approved for use in specialty and vegetable crops to control lepidopteran pests as well as sucking/rasping/chewing pests.

Industry News

Novozymes Advanced Enzymes Increase Ethanol Yields, Plant Profits

Novozymes announces the launch of the Spirizyme T Portfolio, an advanced suite of glucoamylase enzymes with trehalase and other yield enhancing