The Effect of Cold Periods on the Biological Cycle of Marchalina hellenica

SIMPLE SUMMARY: The most important honeydew-producing insect in Greece is Marchalina hellenica (Coccoidea: Marchalinidae), which is a parasite on pine trees. The current work is part of an ongoing research project aiming to provide knowledge on honeydew-producing insects and the impact of critical factors (climate, beekeeping manipulations, honeydew-producing insect phenology) on honeydew honey production. Empirical evidence indicates that among the weather factors, the most important one, at least for spring honeydew secretions, appears to be temperature and, more specifically, the existence of cold winter days. Presently, we investigate the effect of cold periods in February on the life cycle of Marchalina hellenica. Our primary goal is to help beekeepers plan the timely exploitation of honeydew secretions of pine trees. Such a potential will be beneficial for beekeepers, the rural economy, and forest protection. It should be noted that current results highlight the impact of climate change in the field of entomology, and they indicate that the life cycle of Marchalina hellenica is expected to be drastically shorter. ABSTRACT: Climate change is considered a major factor affecting honeybees’ behavior and productivity with major consequences in both honey and agricultural production. Many research studies have expressed serious concerns about the mass losses of bee colonies and the role of bees as pollinators, while others have underlined important issues for the impact of the increase in temperature on honeybee abundance and honey yields. In the present work, we draw our attention to Marchalina hellenica, which is the most important honeydew-producing insect in Greece. A statistically significant forecasting model for the effect of cold periods in February on the life cycle of the insect is constructed, with the aid of the Cumulative Logit Model and the theory of runs. The forecasting model may help beekeepers plan the timely exploitation of honeydew secretions of pine trees, which will be beneficial for beekeepers, the rural economy, and forest protection. The new suggested model also indicates that, in view of the climate change scenarios seen in the literature, the life cycle of M. hellenica is expected to be drastically shorter.