Kepngop Lanvin R K, Wosula Everlyne N, Amour Massoud, Ghomsi Pierre G T, Wakam Louise N, Kansci Germain, Legg James P
Laboratory for Phytobiochemistry and Medicinal Plants Studies, Antimicrobial & Biocontrol Agents Unit (AmBcAU), Department of Biochemistry, Faculty of Science, University of Yaoundé 1, Yaoundé P.O. Box 337, Cameroon.
International Institute of Tropical Agriculture, Dar es Salaam P.O. Box 34441, Tanzania.
Insects. 2024 Aug 30;15(9):657. doi: 10.3390/insects15090657.
(Gennadius) is as a major pest of vegetable crops in Cameroon. These sap-sucking insects are the main vector of many viruses infecting plants, and several cryptic species have developed resistance against insecticides. Nevertheless, there is very little information about whitefly species on vegetable crops and the endosymbionts that infect them in Cameroon. Here, we investigated the genetic diversity of whiteflies and their frequency of infection by endosymbionts in Cameroon. Ninety-two whitefly samples were collected and characterized using mitochondrial cytochrome oxidase I (mtCOI) markers and Kompetitive Allele Specific PCR (KASP). The analysis of mtCOI sequences of whiteflies indicated the presence of six cryptic species (mitotypes) of , and two distinct clades of and . mitotypes identified included: MED on tomato, pepper, okra, and melon; and SSA1-SG1, SSA1-SG2, SSA1-SG5, SSA3, and SSA4 on cassava. The MED mitotype predominated in all regions on the solanaceous crops, suggesting that MED is probably the main phytovirus vector in Cameroonian vegetable cropping systems. The more diverse cassava-colonizing were split into three haplogroups (SNP-based grouping) including SSA-WA, SSA4, and SSA-ECA using KASP genotyping. This is the first time that SSA-ECA has been reported in Cameroon. This haplogroup is predominant in regions currently affected by the severe cassava mosaic virus disease (CMD) and cassava brown streak virus disease (CBSD) pandemics. Three endosymbionts including , and were present in female whiteflies tested in this study with varying frequency. , which has been shown to influence the adaptability of whiteflies, was more frequent in the MED mitotype (75%). and were absent in all whitefly samples. These findings add to the knowledge on the diversity of whiteflies and their associated endosymbionts, which, when combined, influence virus epidemics and responses to whitefly control measures, especially insecticides.
(烟粉虱)是喀麦隆蔬菜作物的主要害虫。这些吸食汁液的昆虫是许多感染植物的病毒的主要传播媒介,并且有几种隐性物种已对杀虫剂产生抗性。然而,关于喀麦隆蔬菜作物上的粉虱物种及其体内感染的内共生菌的信息非常少。在此,我们调查了喀麦隆粉虱的遗传多样性及其被内共生菌感染的频率。收集了92个粉虱样本,并使用线粒体细胞色素氧化酶I(mtCOI)标记和竞争性等位基因特异性PCR(KASP)进行特征分析。粉虱mtCOI序列分析表明存在6种烟粉虱隐性物种(线粒体类型),以及两个不同的烟粉虱和温室粉虱进化枝。鉴定出的线粒体类型包括:番茄、辣椒、秋葵和甜瓜上的MED;木薯上的SSA1-SG1、SSA1-SG2、SSA1-SG5、SSA3和SSA4。MED线粒体类型在茄科作物的所有区域中占主导地位,这表明MED可能是喀麦隆蔬菜种植系统中主要的植物病毒传播媒介。利用KASP基因分型,在木薯上定殖的更为多样的烟粉虱被分为三个单倍群(基于单核苷酸多态性的分组),包括SSA-WA、SSA4和SSA-ECA。这是SSA-ECA首次在喀麦隆被报道。这个单倍群在目前受严重木薯花叶病毒病(CMD)和木薯褐色条纹病毒病(CBSD)大流行影响的地区占主导地位。在本研究中测试的雌性粉虱中存在三种内共生菌,包括、和,频率各不相同。已被证明会影响粉虱适应性的,在MED线粒体类型中更为常见(75%)。和在所有粉虱样本中均未检测到。这些发现增加了关于粉虱及其相关内共生菌多样性的知识,它们共同影响病毒流行以及对粉虱控制措施(尤其是杀虫剂)的反应。