Association of technologies for stink bug and Asian rust control

Embrapa's breeding program is structured into three programs: conventional (non-transgenic), RR and IPRO. But it is important to carry out the phytotechnical positioning of cultivars according to genotypes within production systems, specific to each region. In this way, it is possible to obtain efficient results by exploiting the maximum productive potential of the materials.

As explained by researcher Rodrigo Arroyo Garcia, from Embrapa Agropecuária Oeste (Dourados, MS), at Showtec 2020, positioning has to do with several factors, such as plant population, sowing times, fertilization, management of pests, diseases and weeds. . At the Embrapa stand, Garcia gave a lecture on the positioning of BRS soybean cultivars with Block (stink bug tolerant) and Shield (Asian rust tolerant) technologies, focusing on the planting period in Mato Grosso do Sul.

The transgenic soybean cultivar BRS 543 RR has Block technology, which makes the oilseed tolerant to stink bugs. “It’s super early material. It is not for opening plantings. Ideally, it should be planted at the beginning of October for high productivity.”

Also with Block technology, conventional soybean BRS 391 has resistance to mosaic, root-knot nematode and tolerance to stink bug and has determined growth. ”The last plantations are the ones that have the most problems with stink bug attacks. And this material was developed to close plantings. That is why the most suitable planting is from the end of October until November 15th to have productive potential”, says Garcia.

BRS 511, also conventional, “does well in early planting and has genetic resistance to soybean rust – due to Shield technology. Its productive potential is greatest between September 20th and early October. It has a broad spectrum of recommendations.

Defensive Zero

Embrapa research, carried out by Harley Nonato de Oliveira, researcher and Deputy Head of R&D at Embrapa Agropecuária Oeste, and partners, demonstrated that the association between the Block technology (against stink bugs) of the BRS 543 RR soybean cultivar and the biological control carried out by the parasitoid telenomus podisi (insect registered, in 2019, as a natural agricultural pesticide) brings great benefits to soybean cultivation.

Three experimental areas were installed in Mato Grosso do Sul to analyze this association. In one of them, the telenomus podisi (which, in addition to parasitizing the bed bug, has as one of its characteristics being less sensitive to temperature variations) where the BRS 543 RR material was present. The results of the research prove that it is possible to control it without the application of insecticide. This year, the work will also be repeated with conventional material.

Even with the combination of these technologies, the researcher reinforced that other factors of integrated pest management (IPM) must be taken into consideration. “Crop monitoring is one of the most significant factors of MIP. Whoever is doing it is winning. Chemical control is the last to be adopted.”

Asian soybean rust in the crosshairs

“Asian soybean rust is a cosmopolitan disease, which has spread rapidly throughout the world, except in some microclimates,” said Alexandre Dinnys Roese, an analyst with the research group at Embrapa Agropecuária Oeste, who gave a lecture on genetic resistance to soybean rust. soybeans at the Embrapa stand.

The disease's unicycle is very rapid - six to seven days. It causes openings in the leaves, which loses water, nutrients and photosynthetic area, resulting in yellowing of the leaves, which end up falling. Although it is not transmitted by seed, it is spread by wind and survives in living leaves.

“Control must be focused on the environment, on the pathogen. Cultural resistance to disease is an ancient desire. But we are getting close with the Shield technology, which is tolerant to the disease”, said Roese.

With the Shield shield, which is being incorporated into conventional technologies, RR and IPRO, Asian rust does not reproduce, which provides the flexibility of days to carry out pesticide applications. Shield technology causes the plant to abort dead cells, which results in few or no rust spores. The leaf does not yellow and there is little defoliation. The oilseed does not lose as much water and the fungus does not reproduce. Technology interrupts the disease cycle and is easier to manage.