Phenological responses and a comparative phylogenetic insight of Anarsia lineatella and Grapholita molesta between distinct geographical regions within the Mediterranean basin

Abstract

A unique logistic model for predicting population dynamics of Anarsia lineatella and Grapholita molesta was evaluated on populations sampled from Italy and Greece. Intraspecific mtDNA divergence was additionally estimated in an effort to examine whether regional differences in moth phenologies are associated with genetic divergence. A. lineatella populations displayed closer similarities on phenological responses between the two observation regions. As a result, population fluctuations in both regions could be accurately predicted based on the constructed model. However, that was not the case for G. molesta as its populations exhibited a more regional behaviour, and thus, the model was less accurate. It is notable that degree‐day accumulations above the lower temperature thresholds were recorded in Italy on month earlier than in Greece (1st March in Calabria in contrast to 1st April in Veria). That kind of observed deviations in moth phenologies could be potentially attributed to regional environmental conditions or even genetic differentiation. Despite the low number of individuals analysed, this first attempt to study the levels of intraspecific divergence between Italian and Greek moth populations revealed that both species exhibit evidence of regional‐based separation. Our study provides the first comprehensive phenological comparison between populations of A. lineatella and G. molesta from Italy and Greece. At the same time, the population genetic structure data reveal differentiation between these two regions for both species, something that should be further investigated as it could provide a possible explanation for the observed phenological differences. Moreover, DNA barcoding confirmed that G. molesta pheromone blends attracted at least two morphologically close‐related tortricid moth species. This fact probably explains the phenological variations observed for this species as well as the difficulties in defining the number of non‐overlapping flights.

Different Population Phenologies of Grapholita molesta (Busck) in Two Hosts and Two Nearby Regions in the NE of Spain

“…On the other hand, in the province of Girona, the delay in the start of the first generation added to the increase in the duration of the following generations, suggest an adaptation to local conditions [ 25 ]. This adaptation could also be a result of an increase in the lower development threshold temperature in populations of Girona, as it was reported in other areas of the world [ 22 ].…”

“…In mid-late autumn, when temperatures drop and the days shorten, the fifth instar larvae enter diapause until more favourable conditions occur at the end of winter [ 2 ]. Population dynamics and the annual number of generations of a target species are usually measured in field conditions by recording adult flights with pheromone-baited traps [ 18 , 20 , 23 , 24 , 25 ]. In the Girona and Lleida provinces, captures in traps and field observations indicate that G. molesta has at least four generations per year, but no studies have been conducted to confirm this.…”

Hylotelephium spectabile, a New Host for Carnation Tortrix Moth (Cacoecimorpha pronubana) and Molecular Characterization in Greece

“…Greek sequences were apparently assigned to the clade that contains all European C. pronubana sequences, remaining distinctly separated from those of Spain ( Figure 2 ). Interestingly, divergence between Spanish and Greek (and the other European) sequences is found to be much higher (>3.5%) than commonly expected for intraspecific divergence within tortricid species (e.g., Anarsia lineatella / Grapholita molesta [ 22 ]). Nevertheless, as deep intraspecific barcode divergences have already been detected in a few more tortricid species as well [ 23 ], this finding should be further investigated to conclude whether this pattern is an artifact of non-continuous distribution or by-product of mitochondrial evolution [ 24 ].…”

Stage‐specific probabilistic phenology model of Cydia pomonella (Lepidoptera: Tortricidae) using laboratory maximum likelihood parameter estimates

“…However, there are always concerns regarding the applicability of available prediction models under new conditions and different scenarios (Blomefield & Giliomee, 2011;Kuhrt, Samietz, & Dorn, 2006). For example, there are cases in which a model developed for a particular region turned out to be inaccurate when applied under new circumstances (Damos, Bonsignore, Gardi, & Avtzis, 2014).…”