A ProMED-mail post
ProMED-mail is a program of the
Date: 7 Dec 2010
Soybean samples from northern Mato Grosso have been sent to Embrapa [Brazilian Agricultural Research Corporation] to check for the presence of a disease called Crazy Soybean II. The disease was first discovered in Brazilian soybean fields several years ago, and since then it has been found sporadically in central Brazil.
The organism that causes the disease is yet unknown, and the origin of the disease is also a mystery. During the 2010/11 growing season, the distribution of the disease and the severity varied by region, but it was mostly found in isolated fields in central and northern Mato Grosso. On a localized basis, the disease can cause economic losses, but on a statewide basis, it appears to be another disease that farmers must watch and try to manage.
In June of 2010, researchers formed a working group to monitor the distribution of the disease and to try and ascertain the causal organism. Since all the soybean fields in Brazil receive fungicide applications to control soybean rust, this new disease is probably not a fungus. Speculation is that a virus may be the cause of the abnormality.
--
Communicated by:
ProMED-mail
[The condition of Crazy Soybean II (CSII) was reported in 2009 in all the major soybean producing states of Brazil: Goias, Parana, Para, Maranhao, and most occurrences in Mato Grosso. Yield losses of up to 40 percent were reported.
Symptoms have been described to include abnormal leaf development, unusually high flower and pod abortion, and pods that are heavier but with fewer seeds than normal. Infected soybean plants remain green when normal plants start to dry off, and seed pods never mature.
Since a causal organism has not yet been identified, it is unclear how the samples referred to above could have been "tested." Instead, they may have been subjected to visual inspection, and symptoms were considered to resemble CSII.
Maps
Brazil:
Brazilian states and regions:
Soybean producing states:
Pictures of soybean plantations in Brazil:
Links
Information on Crazy Soybean II:
and
Background on soybean farming in Brazil:
List of major soybean pathogens:
Embrapa:
- Mod.DHA]
[see also:
Nematodes, white mould, rust, soybean - Brazil: (BA, MT) 20100408.1128 Frogeye & leaf rust, soybean - Argentina, Brazil 20100207.0420
2009
----
Leaf rust, soybean - Brazil: new strains 20090501.1644
2006
----
Soybean rust, Asian strain - Brazil 20060611.1628
2004
----
Soybean rust, Asian strain - Brazil 20041222.3374 Soybean rust, Asian strain - Brazil (multistate) 20041209.3266 Soybean rust, Asian strain - Brazil (PR) 20041129.3186
2003
----
Phakopsora pachyrhizi, soybean - Brazil 20031119.2873 Soybean rust - Brazil 20030426.1022 Soybean rust - Brazil (Mato Grosso & Bahia) 20030415.0917 Soybean rust - Brazil (Sao Paulo State) 20030124.0214]
Topics
Species
