Expression of the wheat disease resistance gene Lr34 in transgenic barley leads to accumulation of abscisic acid at the leaf tip

Durable disease resistance genes such as the wheat gene Lr34 are valuable sources of for agricultural breeding programs. encodes an ATP-binding cassette transporter protein involved in transport phytohormone abscisic acid. from is functionally transferable to barley, maize, rice and sorghum. A pleiotropic effect induces development a senescence-like phenotype, referred leaf tip necrosis. We used Lr34-expressing transgenic barley plants elucidate role acid Leaf tips showed accumulation No increase expression was detected tip. Instead, ectopic, Lr34-induced necrosis after removing suggests increased flux towards tip, where it accumulates mediates This redistribution also observed adult with high level growing field coincided well complete against Puccinia hordei Blumeria graminis f. sp. hordei. In line lower level, quantitative still observed, but without significant or apparent Thus, our results imply that fine-tuning essential balance versus deploy