Genome-Wide Association Study of Nigerien and Senegalese Sorghum Genotypes for their Response to Downy Mildew

Sat, 21 Dec 2024 01:38:04 +0000

Sorghum, a multipurpose and drought-tolerant crop, will play an integral role in future food security, especially in the drier tropics. In Niger and Senegal, sorghum supplies the daily caloric needs of millions of inhabitants. One of the major constraints to sorghum production is downy mildew incited by Peronosclerospora sorghi. In this communication, we report the results of a genome-wide association study (GWAS) of a subset of the 120 accessions from Niger and Senegal for downy mildew response under natural infection. The GWAS revealed several loci that have already been reported for their role in plant disease resistance response. Significant SNPs identified on chromosomes 1 and 5 traced back to genomic regions neighboring loci coding for transcription factors involved in biotic stress response. On chromosome 4, the SNP identified was less than 5 kb apart from a gene coding for an E3 ubiquitin ligase enzyme that regulates gene expression levels in relation to plant disease resistance. A membrane-bound protein involved in programmed cell death on chromosome 6 and a transposase on chromosome 8 were identified. Furthermore, a SNP locus that has not been reported previously for biotic stress response was also identified on chromosome 10. This SNP was 4.94 kb downstream of Sobic.010G172100, which encodes a protein similar to the basic helix-loop-helix (bHLH) transcription factor. bHLHs are known for their role in abiotic stress responses. Further work to validate and confirm the activities of the identified SNPs in resistance response will be conducted.

Agronomic Traits and Fungal Diversity between Commercial and Non-commercial Sorghum Fields

Fri, 06 Jun 2025 03:26:58 +0000

Sorghum is a vital crop, especially in drier tropical regions, where it supplies the daily caloric needs for people. However, the productivity and profitablity of crop are hampered by several biotic stresses, including grain mold. Grain mold disease complex is associated with several fungal genera, including those that are mycotoxigenic. The aim of this research was to compare grain mold severity, 100-seed weight, germination rate, and mycoflora of seeds collected from non-commercial and commercial sorghum fields in Burleson County, Texas, Grain mold severity was based on a scale of 1-5, germination rate was based on the percentage of 100-seeds per replicate, and identification of the fungal species under microscope was based on the conidia, conidiophores, colony morphology, and color. Overall, seeds collected from commercial fields exhibited lower grain mold severity and higher seed weight, while seeds from non-commercial fields had higher percent germination rates. The mycoflora analysis of seeds obtained from both non-commercial and commercial fields revealed the occurrence of many microorganisms, as: Alternaria alternata, Bipolaris spp., Curvularia lunata, Aspergillus niger, Colletotrichum sublineola, and other unidentified fungal species and bacterial strains. All identified microorganisms except for A. niger were detected in samples from non-commercial and commercial fields; A. niger (1%) was only recovered from non-commercial fields., In conclusion, lower grain mold infection and higher seed weight were observed in commercial fields when compared to non-commercial or research plots, while percent seed germination rate was higher in non-commercial fields.

Journal of Plant Studies, Issue: Vol.14, No.1

Genome-Wide Association Study of Nigerien and Senegalese Sorghum Genotypes for their Response to Downy Mildew

Agronomic Traits and Fungal Diversity between Commercial and Non-commercial Sorghum Fields