Contrasting performances of generalist and specialistMyzus persicae(Hemiptera: Aphididae) reveal differential prevalence of maternal effects after host transfer

Abstract

Transgenerational maternal effects on performance (rm) after host transfer were evaluated in the generalist aphid Myzus persicae s.s., and in its subspecies specialized on tobacco, M. persicae nicotianae Blackman. We tested whether the performance of these taxa, when reared separately on optimal and suboptimal hosts (as sources of different maternal background) and then transferred to optimal hosts, experienced variations along four successive generations. Additionally, to compare the tolerance of both taxa to stress following host transfers, developmental instability (fluctuating asymmetry and body abnormalities) along the four generations was assessed. Taxon, rearing host, and generation affected the performance after host transfer. In the generalist, there was a significant improvement of rm along generations when transferred from suboptimal to optimal host and a significant decrease when transferred from optimal to optimal host; in the specialist, no increase or decrease occurred in any host transfer treatment. Transfer from suboptimal to optimal hosts caused higher losses of remaining replicates along generations than transfers from optimal to optimal hosts, and the specialist showed higher losses than the generalist. The only significant effect detected in comparisons involving fluctuating asymmetry values was that of taxon on length of siphunculi. Frequency of body abnormalities was not affected by treatments. Collectively, these results show a transgenerational weakening of maternal effects in the generalist but not in the specialist aphid, and suggest that rearing the latter in a suboptimal host causes not easily reversible changes that further give rise to constraints in performance.

Aphid-plant interactions affect the suitability of Myzus spp. as prey for the two spot ladybird, Adalia bipunctata (Coleoptera: Coccinellidae)

“…Sweet pepper, Capsicum annuum L., and tobacco, Nicotiana tabacum L. (Solanaceae), are considered to be optimal host plants for Myzus persicae and M. persicae nicotianae, respectively (Olivares-Donoso et al, 2007). Although both host plants may be colonized by both aphid subspecies, M. p. nicotianae has evolved a degree of specialization on tobacco.…”

Experimental evidence for competitive exclusion of Myzus persicae nicotianae by Myzus persicae s.s. (Hemiptera: Aphididae) on sweet pepper, Capsicum annuum (Solanaceae)

“…Optimal hosts for Chilean clones of M. p. nicotianae and M. persicae s.s. are tobacco and sweet pepper, respectively (Olivares-Donoso et al, 2007). Thus, these taxa colonize sweet pepper after overwintering in hosts where their reproduction potential is not fully achieved.…”

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

“…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] . The green peach-potato aphid, Myzus persicae, is of Asian origin like its primary host, Prunus persica (L.), but has become a world-wide pest of many food crops, especially vegetables like potato, tomato, eggplants and kale crops 12 , and a vector of many plant diseases 13 .…”

“…In contrast, aphids on potato, Solanum tubersoum L., and eggplants, Solanum melongena L., were greenish yellow to light pink, and formed colonies majorly on lower surface of young and older leaves (Figure 1 b). Host plant-based specializations in phenotypic and genotypic variants of M. persicae have been determined in several parts of the world 11,16,17 but none were recorded from India or south Asia despite being a native of Asian countries and a major pest of crops of Solanaceae and Brassicaceae 18,19 . Potato, eggplants and mustard are the principal vegetable food of majority of the people of northeast India and, therefore, these crops are widely cultivated in tropical and subtropical climates of plains, valleys and hills of this region 20 .…”

“…Apterous viviparous female morph of aphids, which is the colonizer of food plants, appears to undergo constant changes in its structures and functions in order to adapt to variable conditions of host environments including presence of allelochemicals which profoundly influence the selection process of host plant 28,29 . The generalist and specialist clones of M. persicae from Chile, South America, Europe and Australia were reported 5,9,11,26 ; generalist genotypes live on optimal as well as suboptimal hosts without compromising their life history fitness, that is, R max of suboptimal hosts significantly improved when transferred to optimal hosts and decreased in reciprocal transfers. In contrast, specialist genotypes performed at fixed level only on optimal host.…”