生物
接种
镰刀菌
普通大麦
野生型
突变体
真菌毒素
大麦
植物抗病性
人口
苗木
葡萄糖基转移酶
植物
禾本科
园艺
遗传学
基因
人口学
社会学
作者
Gerit Bethke,Huang, Y. -J.,Goetz Hensel,Shane Heinen,Chaochih Liu,Skylar R Wyant,Xin Li,Maureen B. Quin,Susan P. McCormick,Peter L. Morrell,Yanhong Dong,Jochen Kumlehn,Silvio Salvi,Franz Berthiller,Gary J. Muehlbauer
标识
DOI:10.1093/plphys/kiad467
摘要
Fusarium head blight (FHB) of barley (Hordeum vulgare) causes yield losses and accumulation of trichothecene mycotoxins (e.g., deoxynivalenol (DON)) in grains. Glucosylation of DON to the nontoxic DON-3-O-glucoside (D3G) is catalyzed by UDP-glucosyltransferases (UGTs), such as barley UGT13248. We explored the natural diversity of UGT13248 in 496 barley accessions and showed that all carried potential functional alleles of UGT13248, as no genotypes showed strongly increased seedling sensitivity to DON. From a TILLING population, we identified two mutant alleles (T368I and H369Y) that, based on protein modeling, likely affect the UDP-glucose binding of UGT13248. In DON feeding experiments, DON-to-D3G conversion was strongly reduced in spikes of these mutants compared to controls, and plants overexpressing UGT13248 showed increased resistance to DON and increased DON-to-D3G conversion. Moreover, field-grown plants carrying the T368I or H369Y mutations inoculated with F. graminearum showed increased FHB disease severity and reduced D3G production. Barley is generally considered to have type II resistance that limits the spread of F. graminearum from the infected spikelet to adjacent spikelets. Point inoculation experiments with F. graminearum showed increased infection spread in T368I and H369Y across the spike compared to wild type, while overexpression plants showed decreased spread of FHB symptoms. Confocal microscopy revealed that F. graminearum spread to distant rachis nodes in T368I and H369Y mutants but was arrested at the rachis node of the inoculated spikelet in wild-type plants. Taken together, our data reveal that UGT13248 confers type II resistance to FHB in barley via conjugation of DON to D3G.
科研通智能强力驱动
Strongly Powered by AbleSci AI