Unprecedented research reveals impact of diseases on soybean

Fundacao MS, a research and technology dissemination company, presented the results of its unprecedented study of the impact of major diseases on soybean productivity. According to Dr. Ana Ruschel, the diseases researched were target spot (Corynespora cassiicola), Asian soybean rust (Phakopsora pachyrhizi), and frogeye leaf spot (Cercospora kikuchii).

Among the impacts of these diseases on soybean cultivation, the greatest was the decrease in productivity. Losses of 15 bags per hectare, 6.6 bags/ha, and 10.4 bags/ha were recorded, respectively, for each disease. For the research, various trials with different fungicides were conducted under adverse climatic conditions.

In another scenario, different spray volumes (a mixture of water, adjuvant, and fungicide) were also evaluated to assess their effectiveness in disease control. In areas where 50 litres of fungicide were applied per hectare, the yield of soybeans was 69 bags per hectare.

The effects were similar between treatments of 80 and 100 litres per hectare, with losses reduced by 7.2 and 6.4 litres per hectare, respectively, compared with 50 litres per hectare. Losses were also mitigated in areas where 120 and 150 litres per hectare were applied, reducing them by 10.3 and 10.9 litres per hectare respectively.

"We know producers who apply as little as 30 liters per hectare. In an area of 10,000 square meters, distributing 30 liters of product is a very low volume,"revealed Dr. Ana Ruschel. What stands out in this work, according to her, is that simply varying the spray volume of the same product can have an impact of up to 10 bags per hectare." By just improving operationally, the producer can spend the same amount in terms of product and avoid a loss of 10 bags," added the Fundação MS researcher.

According to the researcher, reports of farmers seeking solutions to soybean disease from Fundacao MS were different this past season compared to the traditional one." Producers never used to send photos of Cercospora. I started receiving them this year, reporting that they were having difficulty managing the disease. From this, we see new indicators; this disease is starting to attract more attention," highlights Ana.

She warned that Cercospora causes purple seed stains, characterized by a purplish soybean seed. A serious problem that reduces the quality of the grain and its protein content.

″Protecting High-Yield Potential Soybeans″ was the name of the panel where researcher Ana Ruschel presented her lecture. Also participating in this panel were Dr. Jaqueline Huzar Novakowiski, who addressed the challenges in managing soil pathogens in soybean cultivation, and agronomist Thaís de Carvalho, from Sapé Agro, who moderated the debate.

(Editing by Leonardo Gottems, reporter for AgroPages)