Key Lab of Integrated Crop Pest Management of Shandong, China-Australia Joint Institute of Agricultural and Environmental Health, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China.
Guangdong Laboratory of Lingnan Modern Agriculture, Shenzhen, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.
Genomics. 2023 Mar;115(2):110571. doi: 10.1016/j.ygeno.2023.110571. Epub 2023 Feb 4.
The beet armyworm Spodoptera exigua is a polyphagous caterpillar that causes serious damage to many species of crops and vegetables. To gain insight into how this polyphagous insect differs from less harmful oligophagous species, we generated a chromosome-level assembly and compared it to closely related species with the same or different feeding habits.
Based on Illumina and Pacific Biosciences data and Hi-C technology, 425.6 Mb of genome sequences were anchored and oriented into 31 linkage groups, with an N50 length of 14.8 Mb. A total of 24,649 gene models were predicted, of which 97.4% were identified in the genome assembly. Chemosensory genes are vital for locating food: of the four main families, odorant-binding proteins, chemosensory proteins and olfactory receptors showed little difference, whereas gustatory receptors are greatly expanded in S. exigua. Examination of other polyphagous insects confirmed this difference from oligophagous congeners and further identified the bitter receptor subfamily as being particularly affected.
Our high-quality genome sequence for beet armyworm identified a key expansion of the bitter gustatory receptor subfamily in this and other pests that differs crucially from more benign relatives and offers insight into the biology and possible future means of control for these economically important insects.
甜菜夜蛾 Spodoptera exigua 是一种多食性毛毛虫，会对许多种作物和蔬菜造成严重损害。为了深入了解这种多食性昆虫与危害性较小的寡食性物种有何不同，我们生成了一个染色体水平的基因组组装，并将其与具有相同或不同食性的密切相关的物种进行了比较。
基于 Illumina 和 Pacific Biosciences 数据以及 Hi-C 技术，将 425.6 Mb 的基因组序列锚定并定向到 31 个连锁群中，N50 长度为 14.8 Mb。总共预测了 24649 个基因模型，其中 97.4%在基因组组装中得到了鉴定。化学感觉基因对于定位食物至关重要：在四个主要家族中，气味结合蛋白、化学感觉蛋白和嗅觉受体差异不大，而味觉受体在 S. exigua 中则大大扩张。对其他多食性昆虫的研究证实了这种与寡食性近缘种的差异，并进一步确定了苦味受体亚家族受到了特别影响。
我们对甜菜夜蛾的高质量基因组序列，确定了这种昆虫以及其他害虫中苦味味觉受体亚家族的关键扩张，这与更良性的亲缘种有很大的不同，并深入了解了这些对经济重要的昆虫的生物学和可能的未来控制手段。
