Back to Search
Start Over
Expression of the wheat disease resistance gene Lr34 in transgenic barley leads to accumulation of abscisic acid at the leaf tip
- Source :
- Plant physiology and biochemistry : PPB. 166
- Publication Year :
- 2021
-
Abstract
- Durable disease resistance genes such as the wheat gene Lr34 are valuable sources of resistance for agricultural breeding programs. Lr34 encodes an ATP-binding cassette transporter protein involved in the transport of the phytohormone abscisic acid. Lr34 from wheat is functionally transferable to barley, maize, rice and sorghum. A pleiotropic effect of Lr34 induces the development of a senescence-like phenotype, referred to as leaf tip necrosis. We used Lr34-expressing wheat and transgenic barley plants to elucidate the role of abscisic acid in the development of leaf tip necrosis. Leaf tips in Lr34-expressing wheat and barley showed an accumulation of abscisic acid. No increase of Lr34 expression was detected in the leaf tip. Instead, the development of ectopic, Lr34-induced leaf tip necrosis after removing the leaf tip suggests an increased flux of abscisic acid towards the tip, where it accumulates and mediates the development of leaf tip necrosis. This redistribution of abscisic acid was also observed in adult transgenic barley plants with a high Lr34 expression level growing in the field and coincided with leaf tip necrosis as well as complete field resistance against Puccinia hordei and Blumeria graminis f. sp. hordei. In a barley transgenic line with a lower Lr34 expression level, a quantitative resistance against Puccinia hordei was still observed, but without a significant redistribution of abscisic acid or apparent leaf tip necrosis. Thus, our results imply that fine-tuning the Lr34 expression level is essential to balance disease resistance versus leaf tip necrosis to deploy transgenic Lr34 in breeding programs.
- Subjects :
- 0106 biological sciences
0301 basic medicine
Necrosis
Physiology
Transgene
Blumeria graminis
Plant Science
580 Plants (Botany)
Plant disease resistance
01 natural sciences
03 medical and health sciences
chemistry.chemical_compound
10126 Department of Plant and Microbial Biology
1311 Genetics
Ascomycota
1110 Plant Science
Genetics
medicine
10211 Zurich-Basel Plant Science Center
Gene
Abscisic acid
Triticum
Disease Resistance
Plant Diseases
2. Zero hunger
biology
Basidiomycota
fungi
food and beverages
Hordeum
1314 Physiology
biology.organism_classification
Phenotype
Cell biology
Plant Leaves
Plant Breeding
030104 developmental biology
chemistry
medicine.symptom
Puccinia hordei
010606 plant biology & botany
Abscisic Acid
Subjects
Details
- ISSN :
- 18732690
- Volume :
- 166
- Database :
- OpenAIRE
- Journal :
- Plant physiology and biochemistry : PPB
- Accession number :
- edsair.doi.dedup.....cb984d6c46976d68fcbc07c4c3b9a35f