 "Wheat rusts may affect 30% of global output")
Wheat rusts, a type of fungal disease particularly develops in wet seasons, could affect 30 per cent of global wheat output and nearly 40 per cent of the total land area dedicated to wheat planting, a note from the Food and Agricultural Organization of the UN (FAO) said.
Crops across North Africa, West Asia and South Asia could see a sharp impact on yield this year, the FAO note said. The favourable growing conditions for wheat are also good for the rust diseases that affect the crop. So, when there is good precipitation for wheat, chances are high for wheat rusts to best thrive and proliferate.
“The ideal approach to prevent the rusts is to grow the right cultivars which are resistant to rust diseases. This minimises the disease risks. In case of sudden epidemics, fungicide sprays can help mitigate the effects of the disease, but only if they are caught at an early stage,” said Fazil Dusunceli, agriculture officer in FAO’s plant production and protection division and a specialist in wheat rusts.
Dusunceli underlines that monitoring and surveillance should be stepped up for rusts especially in countries like Ethiopia and Kenya, where the growing season is under way and rains have been favourable. If wheat rusts strike on susceptible varieties at an early stage, almost the entire crop can be lost, he said.
Although in warmer lowlands the crop has fully matured or has been harvested, in highland areas, including Central and West Asia, there is still a risk of outbreaks. But there is still time to reduce the losses from yellow rust especially since the crops at higher altitudes and lower temperatures are still maturing.
According to a joint alert issued by the International Maize and Wheat Improvement Center and the International Center for Agricultural Research in the Dry Areas--both FAO partners--conducive climatic conditions “for rusts, especially yellow rust, are resulting in potentially serious outbreaks in the Central and West Asia and North Africa region. Cool and wet conditions have persisted in many countries from Morocco to Bhutan”.
Yellow (stripe) rust has been damaging susceptible varieties in some parts of Afghanistan, Azerbaijan, India, Iran, Iraq, Morocco, Pakistan, Turkey and Uzbekistan. A widespread epidemic similar to the one in 2010 has, nevertheless, not occurred, thanks partly to the progressive introduction of resistant cultivars, chemical control and warming weather conditions. However, in some locations, disease severities increased to high levels requiring fungicide applications.
Wheat rusts, like other pathogens, over time can evolve into new strains that are more virulent and damaging to wheat crops. Ug99 is one such strain of stem rust, which emerged in Uganda in 1998-99. It has since spread beyond East Africa as far as Iran and the worry is that most of the wheat varieties across nearly the same swath of East Africa, West and South Asia are susceptible to this virulent strain. Similarly the Yr 27 virulent strain of yellow rust caused significant losses across the same region from North Africa into West and South Asia during the serious epidemics in 2009 and 2010.
Wheat rusts must be closely monitored as part of a global collective effort. To achieve sustained and improved productivity in wheat, increased investments are needed to support regional and international collaboration efforts to support integrated disease management in the regions often at risk of wheat rust epidemics, specifically in East and North Africa, the Near East and Central and South Asia.
Crops across North Africa, West Asia and South Asia could see a sharp impact on yield this year, the FAO note said. The favourable growing conditions for wheat are also good for the rust diseases that affect the crop. So, when there is good precipitation for wheat, chances are high for wheat rusts to best thrive and proliferate.
“The ideal approach to prevent the rusts is to grow the right cultivars which are resistant to rust diseases. This minimises the disease risks. In case of sudden epidemics, fungicide sprays can help mitigate the effects of the disease, but only if they are caught at an early stage,” said Fazil Dusunceli, agriculture officer in FAO’s plant production and protection division and a specialist in wheat rusts.
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Wheat rusts manifest themselves as yellow, blackish or brown-coloured blisters that form on wheat leaves and stems, full of millions of spores. These spores, similar in appearance to rust, infect the plant tissues, hindering photosynthesis and decreasing the crop’s ability to produce grain.
Dusunceli underlines that monitoring and surveillance should be stepped up for rusts especially in countries like Ethiopia and Kenya, where the growing season is under way and rains have been favourable. If wheat rusts strike on susceptible varieties at an early stage, almost the entire crop can be lost, he said.
Although in warmer lowlands the crop has fully matured or has been harvested, in highland areas, including Central and West Asia, there is still a risk of outbreaks. But there is still time to reduce the losses from yellow rust especially since the crops at higher altitudes and lower temperatures are still maturing.
According to a joint alert issued by the International Maize and Wheat Improvement Center and the International Center for Agricultural Research in the Dry Areas--both FAO partners--conducive climatic conditions “for rusts, especially yellow rust, are resulting in potentially serious outbreaks in the Central and West Asia and North Africa region. Cool and wet conditions have persisted in many countries from Morocco to Bhutan”.
Yellow (stripe) rust has been damaging susceptible varieties in some parts of Afghanistan, Azerbaijan, India, Iran, Iraq, Morocco, Pakistan, Turkey and Uzbekistan. A widespread epidemic similar to the one in 2010 has, nevertheless, not occurred, thanks partly to the progressive introduction of resistant cultivars, chemical control and warming weather conditions. However, in some locations, disease severities increased to high levels requiring fungicide applications.
Wheat rusts, like other pathogens, over time can evolve into new strains that are more virulent and damaging to wheat crops. Ug99 is one such strain of stem rust, which emerged in Uganda in 1998-99. It has since spread beyond East Africa as far as Iran and the worry is that most of the wheat varieties across nearly the same swath of East Africa, West and South Asia are susceptible to this virulent strain. Similarly the Yr 27 virulent strain of yellow rust caused significant losses across the same region from North Africa into West and South Asia during the serious epidemics in 2009 and 2010.
Wheat rusts must be closely monitored as part of a global collective effort. To achieve sustained and improved productivity in wheat, increased investments are needed to support regional and international collaboration efforts to support integrated disease management in the regions often at risk of wheat rust epidemics, specifically in East and North Africa, the Near East and Central and South Asia.