We analyzed the pathogenesis-related generation of H2O2 using the microscopic detection of 3,3-diaminobenzidine polymerization in near-isogenic barley (Hordeum vulgare L.) lines carrying different powdery mildew (Blumeria graminis f.sp. hordei) resistance genes, and in a line expressing chemically activated resistance after treatment with 2,6-dichloroisonicotinic acid (DCINA). Hypersensitive cell death in Mla12 and Mlg genotypes or after chemical activation by DCINA was associated with H2O2 accumulation throughout attacked cells. Formation of cell wall appositions (papillae) mediated in Mlg and mlo5 genotypes and in DCINA-activated plants was paralleled by H2O2 accumulation in effective papillae and in cytosolic vesicles of up to 2 μm in diameter near the papillae. H2O2 was not detected in ineffective papillae of cells that had been successfully penetrated by the fungus. These findings support the hypothesis that H2O2 may play a substantial role in plant defense against the powdery mildew fungus. We did not detect any accumulation of salicylic acid in primary leaves after inoculation of the different barley genotypes, indicating that these defense responses neither relied on nor provoked salicylic acid accumulation in barley.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC32009PMC
http://dx.doi.org/10.1104/pp.119.4.1251DOI Listing

Publication Analysis

Top Keywords

powdery mildew
12
salicylic acid
12
hypersensitive cell
8
cell death
8
mildew fungus
8
acid accumulation
8
h2o2 accumulation
8
accumulation
5
h2o2
5
death papilla
4

Similar Publications

Nanoization of Technical Pesticides: Facile and Smart Pesticide Nanocapsules Directly Encapsulated through "On Site" Metal-Polyphenol Coordination Assembly for Improved Efficacy and Biosafety.

J Agric Food Chem

January 2025

State Key Laboratory of Coordination Chemistry, Key Laboratory of Mesoscopic Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.

Facile pesticide nanocapsules were successfully prepared by directly encapsulating the antisolvent precipitation of pesticides through instantaneous "on site" coordination assembly of tannic acid and Fe, avoiding tedious preparation, time consumption, and large amounts of organic solvents. The pesticide nanocapsules showed excellent resistance to ultraviolet photolysis and rainwater washing owing to the nanocapsule walls. The smart pesticide nanocapsules exhibited the controlled release of pesticides under multidimensional stimuli, such as acidic/alkaline pH, glutathione, HO, phytic acid, laccase, tannase, and sunlight, which were related to the physiological and natural environments of crops, pests, and pathogens.

View Article and Find Full Text PDF

The protracted and immoderate utilization of chemical fertilizers has been detrimental to the composition of fungi in the soil and quality of crops. To ameliorate the adverse effects, a 6-year positioning experiment was undertaken to investigate the impact of substituting 0 % (CF), 25 % (M25), 50 % (M50), 75 % (M75), and 100 % (M100) of 225 kg ha chemical fertilizer nitrogen with manure nitrogen on both soil fungi and maize quality. This study showed that the expansion of Aspergillus heterocaryoticus, Xerochrysium dermatitidis, and Aspergillus penicillioides contributed to heightened levels of amylose and soluble sugars.

View Article and Find Full Text PDF

The Exocyst Subunits EqSec5 and EqSec6 Promote Powdery Mildew Fungus Growth and Pathogenicity.

J Fungi (Basel)

January 2025

Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Tropical Agriculture and Forestry, Haikou 570228, China.

The exocyst complex in eukaryotic cells modulates secretory vesicle transportation to promote exocytosis. The exocyst is also required for the hyphal growth and pathogenic development of several filamentous phytopathogens. Obligate biotrophic powdery mildew fungi cause considerable damage to many cash crops; however, the exocyst's roles in this group of fungi is not well studied.

View Article and Find Full Text PDF

Rosa laevigata is an excellent rose germplasm, highly resistant to aphid, and immune to both rose black spot and powdery mildew disease. It is also a well-known edible plant with a long history of medicinal use in China, having the effects of improving kidney function, inhibiting arteriosclerosis, and reducing inflammation. In this study, we assembled a high-quality chromosome-scale genome for R.

View Article and Find Full Text PDF

The wheat NLR pair RXL/Pm5e confers resistance to powdery mildew.

Plant Biotechnol J

January 2025

Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.

Powdery mildew poses a significant threat to global wheat production and most cloned and deployed resistance genes for wheat breeding encode nucleotide-binding and leucine-rich repeat (NLR) immune receptors. Although two genetically linked NLRs function together as an NLR pair have been reported in other species, this phenomenon has been relatively less studied in wheat. Here, we demonstrate that two tightly linked NLR genes, RXL and Pm5e, arranged in a head-to-head orientation, function together as an NLR pair to mediate powdery mildew resistance in wheat.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!