Identification of QTL associated with resistance to Phytophthora fruit rot in cucumber ( L.).

Phytophthora fruit rot (PFR) caused by the soilborne oomycete pathogen, , can cause severe yield loss in cucumber. With no resistant variety available, genetic resources are needed to develop resistant varieties. The goal of this work was to identify quantitative trait loci (QTL) associated with resistance to PFR using multiple genomic approaches and populations.

Mutations in DNA polymerase δ subunit 1 co-segregate with CMD2-type resistance to Cassava Mosaic Geminiviruses.

Cassava mosaic disease (CMD) suppresses cassava yields across the tropics. The dominant CMD2 locus confers resistance to cassava mosaic geminiviruses. It has been reported that CMD2-type landraces lose resistance after regeneration through de novo morphogenesis.

Large structural variations in the haplotype-resolved African cassava genome.

Cassava (Manihot esculenta Crantz, 2n = 36) is a global food security crop. It has a highly heterozygous genome, high genetic load, and genotype-dependent asynchronous flowering. It is typically propagated by stem cuttings and any genetic variation between haplotypes, including large structural variations, is preserved by such clonal propagation.

Quantitative High-Throughput, Real-Time Bioassay for Plant Pathogen Growth .

Effective assessment of pathogen growth can facilitate screening for disease resistance, mapping of resistance loci, testing efficacy of control measures, or elucidation of fundamental host-pathogen interactions. Current methods are often limited by subjective assessments, inability to detect pathogen growth prior to appearance of symptoms, destructive sampling, or limited capacity for replication and quantitative analysis. In this work we sought to develop a real-time, , high-throughput assay that would allow for quantification of pathogen growth.

Current status and impending progress for cassava structural genomics.

We demystify recent advances in genome assemblies for the heterozygous staple crop cassava (Manihot esculenta), and highlight key cassava genomic resources. Cassava, Manihot esculenta Crantz, is a crop of societal and agricultural importance in tropical regions around the world. Genomics provides a platform for accelerated improvement of cassava's nutritional and agronomic traits, as well as for illuminating aspects of cassava's history including its path towards domestication.

Developmentally regulated activation of defense allows for rapid inhibition of infection in age-related resistance to Phytophthora capsici in cucumber fruit.

Background: Age-related resistance (ARR) is a developmentally regulated phenomenon conferring resistance to pathogens or pests. Although ARR has been observed in several host-pathogen systems, the underlying mechanisms are largely uncharacterized. In cucumber, rapidly growing fruit are highly susceptible to Phytophthora capsici but become resistant as they complete exponential growth.

QTLseqr: An R Package for Bulk Segregant Analysis with Next-Generation Sequencing.

Next-Generation Sequencing Bulk Segregant Analysis (NGS-BSA) is efficient in detecting quantitative trait loci (QTL). Despite the popularity of NGS-BSA and the R statistical platform, no R packages are currently available for NGS-BSA. We present QTLseqr, an R package for NGS-BSA that identifies QTL using two statistical approaches: QTL-seq and G'.

Transcriptomic and metabolomic analyses of cucumber fruit peels reveal a developmental increase in terpenoid glycosides associated with age-related resistance to .

The oomycete, , infects cucumber ( L.) fruit. An age-related resistance (ARR) to this pathogen was previously observed in fruit of cultivar 'Vlaspik' and shown to be associated with the peel.

Function of Cyclophilin1 as a long-distance signal molecule in the phloem of tomato plants.

Tomato (Solanum lycopersicum) diageotropica (dgt) mutants, containing a single mutation in the Cyclophilin1 (SlCyp1) gene, are auxin-insensitive, exhibiting a pleiotropic phenotype including lack of geotropism, abnormal xylem structure, lack of lateral roots (LRs), and elevated shoot-to-root ratio. SlCyp1 is a putative peptidyl-prolyl isomerase that can traffic from shoot to root, where it induces changes in auxin response, LR formation, and xylem development, suggesting it has a role as a long-distance signaling molecule. Here, we explored the mechanism underlying SlCyp1 function in the phloem.

Exocarp Properties and Transcriptomic Analysis of Cucumber (Cucumis sativus) Fruit Expressing Age-Related Resistance to Phytophthora capsici.

Very young cucumber (Cucumis sativus) fruit are highly susceptible to infection by the oomycete pathogen, Phytophthora capsici. As the fruit complete exponential growth, at approximately 10-12 days post pollination (dpp), they transition to resistance. The development of age-related resistance (ARR) is increasingly recognized as an important defense against pathogens, however, underlying mechanisms are largely unknown.