Phenotypic plasticity in host‐plant specialisation in Aphis fabae

Abstract

Abstract. 1. The study of phenotypic plasticity in host utilisation is crucial for predicting evolutionary patterns of insect – plant interactions. The presence of sufficient variation in plasticity may facilitate host race formation and sympatric speciation. 2. Aphis fabae genotypes showed high levels of phenotypic plasticity in the intrinsic rate of natural increase (rm), relative growth rate (RGR), birth weight (BW), adult weight (AW), fecundity (F), and development time (1/d). 3. Thirteen A. fabae genotypes reared both on broad bean and nasturtium exhibited statistically significant genotypic variability in phenotypic plasticity. 4. Some genotypes displayed fitness improvement on novel host plants. 5. Differences in genotypic correlation among fitness components between the two hosts and increased variance on nasturtium indicated different genomic expression on nasturtium. 6. The results indicated that phenotypic plasticity in a novel environment may be a major determinant of the evolutionary trajectory of a parasitic species and might support the idea that speciation starts with phenotypic plasticity.

Effects of extreme, fluctuating temperature events on life history traits of the grain aphid,Sitobion avenae

“…In addition, aphids are known to exhibit a degree of phenotypic plasticitythat is, a capacity to alter their physiology (Powell & Bale, 2004, morphology and behaviour (Ma & Ma, 2012) in response to environmental changes (West-Eberhard, 1989;Gorur et al, 2005)which could have been selected for by the intraand inter-annual climate variability natural populations experience. In addition, aphids are known to exhibit a degree of phenotypic plasticitythat is, a capacity to alter their physiology (Powell & Bale, 2004, morphology and behaviour (Ma & Ma, 2012) in response to environmental changes (West-Eberhard, 1989;Gorur et al, 2005)which could have been selected for by the intraand inter-annual climate variability natural populations experience.…”

A new record of Aphis punicae Passerini, 1863 (Hemiptera: Aphididae) from Korea

“…(Blackman and Eastop, 2013;Passerini, 1863;Sugimoto, 2011), we identified this species, Aphis sp., as A. punicae. However, the genus Aphis generally exhibits a high level of phenotypic plasticity (Agarwala, 2007;Gorur et al, 2005;Rosenheim et al, 1994), which leads to misidentifications of Aphis spp. in trouble with a few morphological differences (Kim et al, 2010).…”

Identification of Generalist and Specialist Phenotypes of the Peach-Potato Aphid <i>Myzus persicae</i> (Insecta : Hemiptera : Aphididae) in Agroecosystem of Northeast India

“…Worldwide, host-adapted races, also called biotypes, phenotypic plasticity, and cryptic species have been reported in aphids, like Aphis gossypii Glover, Aphis fabae Scopoli, Myzus persicae (Sulzer) and Sitobion miscanthi (Takahashi) based on their reaction norms [5][6][7][8][9] and/or genetic differences 10 . In addition, intraspecific generalist and specialist morphs or genotypes adapted to a wide range of unrelated and specialized food plants respectively, have also been reported from different geographical regions 5,[8][9][10][11] .…”

“…It was tested in multiple clonal lineages of M. persicae reared on three host plants by examining their ecological (growth) and biological (developmental and reproductive) performances, the determinants of Darwinian's fitness of phytophagous insects in selection of their host plants [21][22][23] . Aphids from three crop hosts were also subjected to reciprocal host transfer experiments to record the effect of a new host environment on their performances 6,7,22,24 . Three plant species were raised in open nursery till early vegetative stage (2-3 leaf stage) and then ten plants of each species were planted individually in clay pots (20 cm diameter) and were held in water trays on benches illuminated with photo-synthetically active radiation lamps in a greenhouse (temperature: 24  1C, RH: 65%, photoperiod: 16 : 8L : D).…”

“…In contrast, specialist genotypes performed at fixed level only on optimal host. It is argued that higher reproductive rates coupled with greater abundance of secondary host plants in warmer conditions permit asexual aphids to accumulate mutations over short time and these affect growth and reproduction 28 and is the major cause of clonal diversity within sympatric populations 6,23 . This view is vindicated by Ramsey et al 28 who identified 2423 novel genes specific to M. persicae from a large collection of aphids from different geographical regions and found high polymorphism in nucleotide sequence tags.…”