Commodity Online
NEW DELHI: Nobel Prize laureate Dr Norman Borlaug has declared it a global threat. First detected in Uganda 1999, the fungus Ug99 after damaging wheat crops in that region spread to Kenya, Ethiopia. It even crossed the Red Sea as evidenced from reports of its occurrence in Iran.
Not only it spread quickly, but it also generated newer variants able to break the resistance of the varieties grown in the region. This quick spread and ability to generate variant forms in the African continent and beyond is a concern of global wheat community.
When destructive pathogens attack, the consequences are often terrible for farmers. It may be recalled that a stem rust disease caused by a fungus called Puccinia graminis tritici had destroyed 40 percent of America's wheat crop earlier.In India, though the occurrence of this rust had been a regular feature before the introduction of semi- dwarf wheat developed through a network of coordinated research programme by the Indian Council of Agricultural Research minimized the loss caused by this fungus through genes which prevent the fungus from causing any harm to the crop.
Ug99
However, India’s wheat has so far been immune to this destructive pathogen, according to Indian Council of Agricultural Research (ICAR).
The researchers of wheat in India have a position of preparedness in protecting the crop as wheat is accorded top priority in our R&D programmes as it directly impacts the country’s food security. Thus, despite having not faced with any epidemic since last four decades, the strategy of conducting regular countrywide survey and surveillance continued to be in place to monitor the occurrence of all wheat diseases in different regions of the country.
Trap-nurseries are also raised to monitor the chance of any stray infection of the disease. So far any presence the Ug99 or its variants has not been noticed from any part of our country. Not willing to take any chances with the potential threat, the Council has taken necessary steps in wheat research programme to safeguard the wheat crop against destructive pathogen like Ug99.
In view of the fact that the Ug99 does not exist in India, the testing of resistance (a plant defense mechanism) against it can only be undertaken in Kenya where the disease is prevalent.
Hence the ICAR, in collaboration with International Wheat and Maize Research Centre (CIMMYT), Mexico has stated a testing program of wheat at Njoro in Kenya since 2005. The tests have shown that there are many Indian wheat varieties with resistance to Ug99 and its variants. The presence of diverse resistance in some of these varieties is very encouraging as it would help wheat to fight against Ug99 and other future threats of this magnitude.
Accordingly, the resistant wheat materials are being multiplied and provided to wheat breeders for further research and the seed of already released varieties with resistance to Ug99 or its variants are being multiplied. For example, during the years 2007-08 more than 4,000q of breeder seed of 11 wheat varieties having Ug99 resistance namely, GW 273, GW 322, HI 1500, HD 2781, MP 4010, HUW 510, MACS 2846(durum), HI 8498 (durum), UP 2338, DL 153-2 and HW 1085 was produced. In the recently concluded national wheat workshop at Hisar in August 2008, another new variety Raj 4120 resistant to Ug99 has also been identified for release.
Presently, the priority of ICAR is on extensive surveys in the target areas to detect the first infection of Ug99 or its variants, if and when it comes, before it acquires alarming proportions.
The experience suggests that it takes a few seasons for the race to build up and appear on a large scale to cause economic losses. Thus, even in remotest event of Ug99 reaching India, the years required for it to take epidemic proportions would be utilized to multiply the already identified resistant varieties, breed new varieties and then aggressively distributing these to the cultivators to avoid any loss in the farmer's field.
As an immediate relief measure, chemical control technology is also available to ensure that this race does not spread and cause damage. As a precautionary measure, a special team has been constituted to survey and monitor the summer wheat crop in the higher hills of Himachal Pradesh, Jammu & Kashmir, Southern hills in Tamil Nadu to detect and track down Ug99 or its variants.
A new version of the popular variety PBW 343 which is reported to possess inbuilt resistance to Ug99 is also being acquired from International Centre for Agricultural Research in Dryland Areas (ICARDA), Syria for its seed multiplication and utilization in the country.
In addition, India is proactively participating in the Borlaug Global Rust Initiative (BGRI) Programme as its core member to be in a state of preparedness against any serious consequences because of this disease. The programmes at the International level are aimed at sensitizing the nations in the migration path of Ug99 to grow resistant varieties that would help decrease the inoculum build up and its subsequent migration to other countries. The tracking programme for the Ug99 and its variants is already on to monitor its migration into newer areas.
Thus a multi-pronged strategy is already in place to render the rust ineffective even in the most unlikely event of Ug99 striking Indian territory. “We are confident and f eel that such a vibrant technical programme will stand by Indian farming community and will be able to avoid any crisis likely to be caused by this disease,” ICAR said in a report.
The Indian wheat programme is fully geared to take on the challenge of overcoming the challenge posed by Ug99. Since cooperative and collaborative network across geo-political limits are part of a global strategy against the rust, in November, 2008, India will host an International Conference Wheat Stem Rust Ug99 – A Threat to Food Security for stressing the importance and also forging a Regional/Global strategy to address this threat.
