Drought is a major stress severely affecting plant growth and crop
productivity. A previous study showed that TaWRKY2 from wheat plays an
important role in drought stress tolerance. Chinese Academy of Sciences
researchers led by Huiming Gao further studied the TaWRKY2gene and its
promoter.



The TaWRKY2 promoter was found to be induced by drought, salt, and heat
stresses as well as abscisic acid (ABA). The team then generated
TaWRKY2-overexpressing transgenic wheat, and found that these seedlings
exhibited significantly enhanced tolerance to drought stress compared with
wild type plants. Moreover, the transgenic lines had higher contents of free
proline, soluble sugars, and chlorophyll.



During a prolonged drought stress before the heading stage, the growth of
wildtype plants was inhibited, while the TaWRKY2-overexpressing lines
progressed to the heading stage. The cumulative effects of drought stress
resulted in increased grain yield in transgenic wheat.



TaWRKY2 was found capable of enhancing drought tolerance and increasing
grain yield in wheat. The gene is a promising candidate for improving the
drought tolerance of wheat cultivars.



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