Combination of linkage and association mapping with genomic prediction to infer QTL regions associated with gray leaf spot and northern corn leaf blight resistance in tropical maize.

Among the diseases threatening maize production in Africa are gray leaf spot (GLS) caused by and northern corn leaf blight (NCLB) caused by . The two pathogens, which have high genetic diversity, reduce the photosynthesizing ability of susceptible genotypes and, hence, reduce the grain yield. To identify population-based quantitative trait loci (QTLs) for GLS and NCLB resistance, a biparental population of 230 lines derived from the tropical maize parents CML511 and CML546 and an association mapping panel of 239 tropical and sub-tropical inbred lines were phenotyped across multi-environments in western Kenya.

Population genomic analyses suggest recent dispersal events of the pathogen Cercospora zeina into East and Southern African maize cropping systems.

A serious factor hampering global maize production is gray leaf spot disease. Cercospora zeina is one of the causative pathogens, but population genomics analysis of C. zeina is lacking.

Deep Learning Diagnostics of Gray Leaf Spot in Maize under Mixed Disease Field Conditions.

Maize yields worldwide are limited by foliar diseases that could be fungal, oomycete, bacterial, or viral in origin. Correct disease identification is critical for farmers to apply the correct control measures, such as fungicide sprays. Deep learning has the potential for automated disease classification from images of leaf symptoms.

Time-Course RNAseq Reveals Effectors and Pathogenicity Determinants.

(sexual stage ) is the hemibiotrophic causal agent of northern leaf blight of maize and sorghum. This study aimed to identify the genes involved in host colonization during the biotrophic and necrotrophic phases of infection. It also aimed to identify race-specific differences in gene expression.

Assembly of Transcriptomes From a B73 Maize Line Introgressed With a QTL for Resistance to Gray Leaf Spot Disease Reveals a Candidate Allele of a Lectin Receptor-Like Kinase.

Gray leaf spot (GLS) disease in maize, caused by the fungus , is a threat to maize production globally. Understanding the molecular basis for quantitative resistance to GLS is therefore important for food security. We developed a assembly pipeline to identify candidate maize resistance genes.

Application of Chloroplast Phylogenomics to Resolve Species Relationships Within the Plant Genus Amaranthus.

Amaranthus species are an emerging and promising nutritious traditional vegetable food source. Morphological plasticity and poorly resolved dendrograms have led to the need for well resolved species phylogenies. We hypothesized that whole chloroplast phylogenomics would result in more reliable differentiation between closely related amaranth species.

IMA Genome-F 8: Draft genome of , , and .

The genomes of , , and are presented in this genome announcement. Three of these genomes are from plant pathogens and otherwise economically important fungal species. and are not known to cause significant disease but are closely related to species of economic importance.

RNA-Seq analysis of resistant and susceptible sub-tropical maize lines reveals a role for kauralexins in resistance to grey leaf spot disease, caused by Cercospora zeina.

Background: Cercospora zeina is a foliar pathogen responsible for maize grey leaf spot in southern Africa that negatively impacts maize production. Plants use a variety of chemical and structural mechanisms to defend themselves against invading pathogens such as C. zeina, including the production of secondary metabolites with antimicrobial properties.

Complementation of CTB7 in the Maize Pathogen Cercospora zeina Overcomes the Lack of In Vitro Cercosporin Production.

Gray leaf spot (GLS), caused by the sibling species Cercospora zeina or Cercospora zeae-maydis, is cited as one of the most important diseases threatening global maize production. C. zeina fails to produce cercosporin in vitro and, in most cases, causes large coalescing lesions during maize infection, a symptom generally absent from cercosporin-deficient mutants in other Cercospora spp.

Evidence for salicylic acid signalling and histological changes in the defence response of Eucalyptus grandis to Chrysoporthe austroafricana.

Eucalyptus species are cultivated for forestry and are of economic importance. The fungal stem canker pathogen Chrysoporthe austroafricana causes disease of varying severity on E. grandis.

Localization and Transcriptional Responses of in Identify Putative Pathogenicity Factors.

is a fungal pathogen that causes the development of stem cankers on susceptible trees. Clones of that are partially resistant and highly susceptible have been identified based on the extent of lesion formation on the stem upon inoculation with These interactions have been used as a model pathosystem to enhance our understanding of interactions between pathogenic fungi and woody hosts, which may be different to herbaceous hosts. In previous research, transcriptomics of host responses in these two clones to suggested roles for salicylic acid and gibberellic acid phytohormone signaling in defense.

Systems genetics reveals a transcriptional network associated with susceptibility in the maize-grey leaf spot pathosystem.

We used a systems genetics approach to elucidate the molecular mechanisms of the responses of maize to grey leaf spot (GLS) disease caused by Cercospora zeina, a threat to maize production globally. Expression analysis of earleaf samples in a subtropical maize recombinant inbred line population (CML444 × SC Malawi) subjected in the field to C. zeina infection allowed detection of 20 206 expression quantitative trait loci (eQTLs).

Cercospora zeina from Maize in South Africa Exhibits High Genetic Diversity and Lack of Regional Population Differentiation.

South Africa is one of the leading maize-producing countries in sub-Saharan Africa. Since the 1980s, Cercospora zeina, a causal agent of gray leaf spot of maize, has become endemic in South Africa, and is responsible for substantial yield reductions. To assess genetic diversity and population structure of C.

Dual RNA-Sequencing of Eucalyptus nitens during Phytophthora cinnamomi Challenge Reveals Pathogen and Host Factors Influencing Compatibility.

Damage caused by Phytophthora cinnamomi Rands remains an important concern on forest tree species. The pathogen causes root and collar rot, stem cankers, and dieback of various economically important Eucalyptus spp. In South Africa, susceptible cold tolerant Eucalyptus plantations have been affected by various Phytophthora spp.

Genome-wide mapping of histone H3 lysine 4 trimethylation in Eucalyptus grandis developing xylem.

Background: Histone modifications play an integral role in plant development, but have been poorly studied in woody plants. Investigating chromatin organization in wood-forming tissue and its role in regulating gene expression allows us to understand the mechanisms underlying cellular differentiation during xylogenesis (wood formation) and identify novel functional regions in plant genomes. However, woody tissue poses unique challenges for using high-throughput chromatin immunoprecipitation (ChIP) techniques for studying genome-wide histone modifications in vivo.

Investigating the molecular underpinnings underlying morphology and changes in carbon partitioning during tension wood formation in Eucalyptus.

Tension wood has distinct physical and chemical properties, including altered fibre properties, cell wall composition and ultrastructure. It serves as a good system for investigating the genetic regulation of secondary cell wall biosynthesis and wood formation. The reference genome sequence for Eucalyptus grandis allows investigation of the global transcriptional reprogramming that accompanies tension wood formation in this global wood fibre crop.

Mapping QTL conferring resistance in maize to gray leaf spot disease caused by Cercospora zeina.

Background: Gray leaf spot (GLS) is a globally important foliar disease of maize. Cercospora zeina, one of the two fungal species that cause the disease, is prevalent in southern Africa, China, Brazil and the eastern corn belt of the USA. Identification of QTL for GLS resistance in subtropical germplasm is important to support breeding programmes in developing countries where C.

The identification and differential expression of Eucalyptus grandis pathogenesis-related genes in response to salicylic acid and methyl jasmonate.

Two important role players in plant defence response are the phytohormones salicylic acid (SA) and jasmonic acid (JA); both of which have been well described in model species such as Arabidopsis thaliana. Several pathogenesis related (PR) genes have previously been used as indicators of the onset of SA and JA signaling in Arabidopsis. This information is lacking in tree genera such as Eucalyptus.

Gene-for-gene tolerance to bacterial wilt in Arabidopsis.

Bacterial wilt caused by Ralstonia solanacearum is a disease of widespread economic importance that affects numerous plant species, including Arabidopsis thaliana. We describe a pathosystem between A. thaliana and biovar 3 phylotype I strain BCCF402 of R.