Variability of morphological characteristics of middle-European bees of the ‘Northern M’ line

Abstract

The aim of the study was to evaluate the variability of morphological characteristics of native middle-European bees (Apis m. mellifera) of the ‘Northern M’ line. The research covered characteristics of breed (the length of proboscis, the cubital index), body size (the width of tergite 4 and the sum of widths of tergites 3 and 4) and wing size (length and width). The study compared bees harvested from a leading apiary and from collaborating apiaries participating in a program for the protection of genetic resources of bees of this line. The material for the study was harvested in 10 consecutive years. The samples were collected by the “cluster drawing” method (the multi-stage method of clustering described by Zee et al. in 2013). Each sample consisted of 25 to 30 bees. The frames were loaded in an instrument for the morphological measurement of bees (Apimeter). Seven measurements were taken on prepared body parts of each bee. The length and width of the wing and the length of the cubital vein were measured on the right front wing (hereinafter referred to as the “wing”). In addition, the width of abdominal tergites 3 and 4 and the length of proboscis were measured in each instance. In total, 4 291 bees were harvested and 30 037 measurements were taken. The conclusion is that the program for the protection of genetic resources of bees of the ‘Northern M’ line can be implemented in Poland based on the leading apiary and on the collaborating apiaries, and bees of this line display characteristics of middle-European bees. Moreover, the study demonstrated a consistency of values of the studied characteristics of the ‘Northern M’ line with the applicable references of morphological characteristics for Apis m. mellifera. In addition, based on a review of results of the author’s research and based on collected literature originating from the 1960s, the study proves that a dwarfing trend has emerged among middle-European bees.