In pursuit of more resistance
Researchers are trying to incorporate genetic resistance
into cultivars, but this is not always possible, as the fungus
of Asian rust changes at a faster speed than the discovery of
new technologies for its control. “The increase in the sup-
ply of cultivars with resistance to soybean rust should not
be significant, because only a few genetic enhancement
programs are focused on this problem, though it would be
a good idea if they were, because it would be a good aid in
reducing the selection pressure of resistance to fungicides”,
she comments. “Old technologies, like multi-site fungi-
cides, are returning to boost the efficiency of specific site-
fungicides in delaying the speed of resistance selection”.
In the long run, some studies conducted by different
groups, involve the higher resistance of plants with the in-
corporation of genes involved in the nonhost resistance,
through conventional and transgenic crossing. Another
proposal spots the use of technologies utilizing RNA inter-
ference (RNAi), which is based on the technology of patho-
gen gene silencing. But these technologies are still a long
way from the fields”, she anticipates. According to the Em-
brapa Soybean phytopathologist, when scientific solutions
are not possible, research tries to advise on the best man-
agement, cultural and chemical manners for the farmers to
avoid productivity reductions.
Thereare120pesticidesregistered
intheMapaforkeepingthe
diseaseundercontrol
