Unveiling the draft genome of the seed gall nematode, Anguina tritici: Insights and analysis

Abstract

Anguina tritici, a plant parasitic nematode (PPN) from clade IV of the phylum Nematoda, causes earcockle and tundu diseases in wheat. It stands out from other PPNs due to its ability to parasitize wheat plant seeds and its long-term survival capability under anhydrobiosis conditions within the seeds. Therefore, the genome of A. tritici provides an opportunity to understand the genomic basis for its adaptation to parasitize the aerial parts of the plant. The Illumina MiSeq sequencing strategy yielded a total of 11,065,381,294 bases, with a read count of 40,210,848. The genome, with a size of 164 MB and 39,965 protein-coding genes, was sequenced at 60-fold coverage. Key statistics include a GC content of 39.1 %, Q20 % of 92.73, and Q30 % of 84.08. KEGG analysis identified the involvement of genes in 375 different pathways, highlighting significant pathways related to parasitism, anhydrobiosis, and stress responses. Comparative genomic analysis yielded insightful results regarding the orthologous relationships among the six analyzed species, including A. tritici, Aphelenchoides besseyi, Bursaphelenchus xylophilus, Ditylenchus destructor, Globodera pallida, and Meloidogyne incognita. Sixty-one overlaps were identified, indicating shared orthologous clusters among these species. A single-copy orthologue-based phylogenetic tree showed A. tritici and D. destructor in a monophyletic group. Expert functional annotations revealed the occurrence of several gene homologues involved in developmental processes, neuropeptide signaling, aging, anhydrobiosis, parasitism, RNA interference (RNAi), chemosensory mechanisms, and sex determination processes in A. tritici. These findings offer a comprehensive genetic framework for understanding the parasitism and survival strategies of A. tritici, with significant implications for developing novel control methods and advancing research in plant pathology and Nematology.