Asexual reproduction of a few genotypes favored the invasion of the cereal aphidRhopalosiphum padiin Chile

Abstract

Background Aphids (Hemiptera: Aphididae) are insects with one of the highest potentials for invasion. Several aphid species are present globally due to introduction events; they represent important pests of agroecosystems. The bird cherry-oat aphid Rhopalosiphum padi (Linnaeus) is a major pest of cereals and pasture grasses worldwide. Here, we report the genetic features of populations of R. padi that colonize different cereal crops in central Chile. Methods Rhopalosiphum padi individuals were collected in central Chile and genotyped at six microsatellite loci. The most frequent multilocus genotype (MLG) was then studied further to assess its reproductive performance across cereal hosts under laboratory conditions. Results Populations of R. padi in Chile are characterized by a low clonal diversity (G/N = 62/377 = 0.16) and the overrepresentation of a few widely distributed MLGs. One of the MLGs constituted roughly half of the sample and was observed in all sampled populations at high frequencies. Furthermore, this putative aphid “superclone” exhibited variations in its reproductive performance on cereals most commonly cultivated in Chile. The sampled populations also exhibited weak signs of genetic differentiation among hosts and localities. Our findings suggest that (1) obligate parthenogenesis is the primary reproductive mode of R. padi in Chile in the sampled range and (2) its introduction involved the arrival of a few genotypes that multiplied asexually.

Rapid turnover of a pea aphid superclone mediated by thermal endurance in central Chile

“…Aphid populations inhabiting central Chile represent an ideal system to study the response and persistence of an asexual population facing environmental change after local aphid populations are generally characterized by the predominance of a single or few superclones, regardless of the aphid species [23,[33][34][35][36]. On the one hand, despite the natural geographical barriers of the country [37], several aphid invasion processes have been reported in this range, which has increased in frequency given the growth in trade practices [38].…”

“…However, while superclones are common and their arrival, establishment, and expansion are well-documented (e.g. [23,33]), the factors that promote their persistence or exclusion in a given territory are poorly understood (but see Peccoud et al [23]).…”

CUAD biotechnology offers 0.5 USD per hectare for aphid control: innovative platform for low-cost plant protection

“…Their management is challenging because the mobility of aphids is extremely high [29]. Also, these pests reproduce predominantly asexually [30], one female leaves 10-90 offspring in 7-10 days and therefore, theoretically, could produce billions of offspring in one growing season in the absence of mortality factors [31]. Chemical insecticides have been used to control aphids, and these pests quickly develop resistance to various classes of chemical insecticides, including neonicotinoids, carbamates, organophosphates, organochlorines, and pyrethroids [32].…”

Estimating the Global Geographical Distribution Patterns of the Invasive Crop Pest Diuraphis noxia Kurdjumov under Current and Future Climatic Scenarios

“…Globally, ICPs cause economic losses of up to USD 70 billion annually, resulting in yield losses of more than 40% [ 6 ]. Invasive aphids are important ICPs having various hosts, mainly damaging wheat, sorghum, sugarcane, and other crops; additionally, they are one of the most invasive phytophagous insects, which are widely distributed across all temperature environments worldwide [ 7 , 8 , 9 , 10 , 11 ]. For example, almost every aphid population on the Hawaii Islands is an invasive species that causes devastating attacks on the Hawaiian ecosystem [ 12 ].…”