Abstract
Fusarium virguliforme causes the serious disease sudden death syndrome (SDS) in soybean. Host resistance to this pathogen is partial and is encoded by a large number of quantitative trait loci, each conditioning small effects. Breeding SDS resistance is therefore challenging and identification of single-gene encoded novel resistance mechanisms is becoming a priority to fight this devastating this fungal pathogen. In this transcriptomic study we identified a few putative soybean defense genes, expression of which is suppressed during F. virguliforme infection. The F. virguliforme infection-suppressed genes were broadly classified into four major classes. The steady state transcript levels of many of these genes were suppressed to undetectable levels immediately following F. virguliforme infection. One of these classes contains two novel genes encoding ankyrin repeat-containing proteins. Expression of one of these genes, GmARP1, during F. virguliforme infection enhances SDS resistance among the transgenic soybean plants. Our data suggest that GmARP1 is a novel defense gene and the pathogen presumably suppress its expression to establish compatible interaction.
Highlights
Soybean [Glycine max (L.) Merr.] is an economically important crop
In order to monitor the expression of genes during infection, roots tissues were harvested at different time periods: (i) S1, early time period (ETP) of pooled root samples, 3 and 5 days following water treatment; (ii) S2, late time period (LTP) of pooled root samples, 10 and 25 days following water treatment; (iii) S3, ETP of pooled root samples, 3 and 5 days following F. virguliforme infection; (iv) S4, LTP of pooled root samples, 10 and 24 days following F. virguliforme infection
We considered the genes showing at least 10-fold or more changes in transcript levels between infected and control tissues as the differentially expressed genes (DEGs). We considered only those genes as DEGs that have shown to contain at least five sequence reads or fragments per kilobase pair exon sequences in at least one of the treatments considered for comparison
Summary
For RNA-sequencing (RNA-seq) experiment, soybean seeds of cultivar ‘Williams 82’ were sown in vermiculite and grown under the dark for 10 days according to Bhattacharyya and Ward [35]. Etiolated seedlings were inoculated with either water (water treatment) or F. virguliforme conidial spores (infection) at a concentration of 107 spores ml-1. Root samples were harvested at different time-points, 3, 5, 10 and 24 days following inoculation with F. virguliforme or treatment with sterile water [10]. For three independent RT-PCR experiments, RNA samples were prepared from roots harvested 8 h, 12 h, 1 d, 3 d, and 5 d following either treatment with water or inoculation with F. virguliforme.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have