Wheat Resistance Gene Lr34 Confers Partial Blast Resistance in Rice

The Lr34 gene confers durable and partial resistance against rust fungi and powdery mildew in wheat (Triticum aestivum). An Lr34-like broad disease resistance and durability has not been described in other cereals. Researchers led by Simon G. Krattinger and Justine Sucher of the University of Zurich in Switzerland inserted the Lr34 allele into the rice cultivar Nipponbare.

Transgenic rice plants expressing Lr34 showed increased resistance against multiple isolates of the Magnaporthe oryzae, the causal agent of rice blast. Host cell invasion of rice blast was delayed in the transgenic rice plants, resulting in smaller necrotic lesions on leaves. However, development of leaf tip necrosis during early seedling growth had a negative impact on axillary shoots and spikelets in some transgenic lines.

Lr34 in rice was also effective against other pathogens different from obligate biotrophic rusts and mildew fungi. The gene could therefore be used as a source in rice breeding to improve broad-spectrum disease resistance.

For more information on the study, read the article in Plant Biotechnology Journal.