Improving wheat varieties in Kazakhstan

Plant breeder Zagipa Sapakhova spent two months this summer studying tan spot and Septoria leaf blotch with SDSU small grains pathologist Shaukat Ali.

"I learned techniques that I will take home and apply," Sapakhova said. The Institute of Plant Biology and Biotechnology works with agricultural breeding stations to develop improved crop varieties in Kazakhstan, a nation in Asia sandwiched between Russia and China.

Ali met Sapakhova through his work with the CIMMYT International Maize and Wheat Improvement Center in El Batán, Mexico, which seeks to provide training opportunities for agricultural researchers from developing countries.

Farmers in Kazakhstan produce 17 to 20 million metric tonnes of wheat per year and the country exports up to 10 million tonnes to Europe, the Middle East and neighboring countries, according to Sapakhova. However, producers lose anywhere from 10 percent to as much as 50 percent of their wheat crop due to tan spot and Septoria leaf blotch.

Using fungal isolates that Ali provided, Sapakhova became familiar with methods of identifying biomarkers for the tan spot toxin genes using polymerase chain reaction analysis and gel electrolysis. She will then use these techniques to characterize tan spot-causing races that affect wheat in Kazakhstan.

Producers can use fungicide to fight these diseases, but breeders can save the growers money if they find out whether new varieties are susceptible or resistant before they are commercialized, Ali explained.

Sapakhova brought 223 varieties of wheat seeds to evaluate. She inoculated the seedlings with spores to determine their resistance or susceptibility to the tan spot and Septoria leaf blotch.

She also tested the Kazakhstan wheat genotypes using two host-selective toxins produced by tan spot.

Toxins trigger symptoms in the seedlings faster and are easier to handle than spores, according to Ali. The plants begin to show signs of susceptibility within two to four days.

"Race 1 produces Ptr ToxA and Race 5 produces Prt ToxB," Sapakhova explained. As she examined the leaves, she pointed out, "If the leaves become yellow, that's chlorosis and it's because of race 5."