Reactive oxygen species (ROS) are vital for plant immunity and regulation of their production is crucial for plant health. While the mechanisms that elicit ROS production have been relatively well studied, those that repress ROS generation are less well understood. Here, via screening Brachypodium distachyon RNA interference (RNAi) mutants, we identified BdWRKY19 as a negative regulator of ROS generation whose knockdown confers elevated resistance to the rust fungus Puccinia brachypodii. The three wheat paralogous genes TaWRKY19 are induced during infection by virulent P. striiformis f. sp. tritici (Pst) and have partially redundant roles in resistance. The stable overexpression of TaWRKY19 in wheat increased susceptibility to an avirulent Pst race, while mutations in all three TaWRKY19 copies conferred strong resistance to Pst by enhancing host plant ROS accumulation. We show that TaWRKY19 is a transcriptional repressor that binds to a W-box element in the promoter of TaNOX10, which encodes an NADPH oxidase and is required for ROS generation and host resistance to Pst. Collectively, our findings reveal that TaWRKY19 compromises wheat resistance to the fungal pathogen and suggest TaWRKY19 as a potential target to improve wheat resistance to the commercially important wheat stripe rust fungus.
Wheat stripe rust, caused by
Puccinia striiformis
f. sp.
tritici
(
Pst
), is one of the most serious threats to wheat production worldwide. Changes of
Pst
virulence may circumvent resistance in wheat varieties, and application of fungicides may cause environmental problems. Parasites of
Pst
can be used to develop biological agents for environmentally friendly control of this fungal disease. Here, we report a hyperparasitic fungus isolated from
Pst
and identified it as
Simplicillium obclavatum
through molecular and morphological characterizations. We demonstrated that inoculation of
Pst
-infected wheat leaves with
S
.
obclavatum
reduced the production and germination rate of
Pst
urediniospores. Therefore,
S. obclavatum
has the potential to be developed into a biological control agent for managing wheat stripe rust.
Wheat rust outbreaks have caused significantly economic losses all over the world. Puccinia striiformis f. sp. tritici (Pst) is an obligate biotrophic fungus causing stripe rust on wheat. Application of fungicides may cause environmental problems. The effects of hyperparasites on plant pathogens are the basis for biological control of plant pathogenic fungi and parasites of Pst have great value in biological agents development. Here, we report the isolation and characterization of isolate of Cladosporium cladosporioides from Pst based on morphological characterization and analysis of molecular markers. The hyperparasitic isolate was isolated from taupe-colored uredinia of Pst. Upon artificial inoculation, the hyperparasitic isolate was able to reduce the production and germination rate of Pst urediospores, and Pst uredinia changed color from yellow to taupe. Scanning electron microscopy demonstrated that the strain could efficiently colonize Pst urediospores. Therefore, the isolate has the potential to be developed into a biological control agent for managing wheat stripe rust.
This paper points at the role of the planning document defining spatial policy in creating the sustainable development of a commune. The study serves to analyse whether the planning of spatial development of communes under environmental protection in the vicinity of the city of Wrocław is performed in accord with the functioning of the natural environment and fosters the sustainable development of villages. The evaluation was performed based on a set of approved indicators for evaluating sustainable development with regard to environmental order, as well as approved indicators for the sustainable development of the spatial policy on a local level.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.